hwmon: PMBus device driver
authorGuenter Roeck <guenter.roeck@ericsson.com>
Thu, 27 Jan 2011 04:09:02 +0000 (20:09 -0800)
committerGuenter Roeck <guenter.roeck@ericsson.com>
Tue, 15 Mar 2011 05:36:26 +0000 (22:36 -0700)
This driver adds support for hardware monitoring features of various PMBus
devices.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/pmbus.c [new file with mode: 0644]
drivers/hwmon/pmbus.h [new file with mode: 0644]
drivers/hwmon/pmbus_core.c [new file with mode: 0644]
include/linux/i2c/pmbus.h [new file with mode: 0644]

index d4ffc6052083fa3bde8c1491a9fb1e8d2eab9592..ac116693e3576d9aa8c93f37464778e47df8685b 100644 (file)
@@ -756,6 +756,31 @@ config SENSORS_PCF8591
          These devices are hard to detect and rarely found on mainstream
          hardware.  If unsure, say N.
 
+config PMBUS
+       tristate "PMBus support"
+       depends on I2C && EXPERIMENTAL
+       default n
+       help
+         Say yes here if you want to enable PMBus support.
+
+         This driver can also be built as a module. If so, the module will
+         be called pmbus_core.
+
+if PMBUS
+
+config SENSORS_PMBUS
+       tristate "Generic PMBus devices"
+       default n
+       help
+         If you say yes here you get hardware monitoring support for generic
+         PMBus devices, including but not limited to BMR450, BMR451, BMR453,
+         BMR454, and LTC2978.
+
+         This driver can also be built as a module. If so, the module will
+         be called pmbus.
+
+endif # PMBUS
+
 config SENSORS_SHT15
        tristate "Sensiron humidity and temperature sensors. SHT15 and compat."
        depends on GENERIC_GPIO
index 46819818ef514cd065e1f796246b14d8fc4240fd..09e67955fd577255ef44d8f008c87fda9a91d00f 100644 (file)
@@ -114,6 +114,10 @@ obj-$(CONFIG_SENSORS_W83L786NG)    += w83l786ng.o
 obj-$(CONFIG_SENSORS_WM831X)   += wm831x-hwmon.o
 obj-$(CONFIG_SENSORS_WM8350)   += wm8350-hwmon.o
 
+# PMBus drivers
+obj-$(CONFIG_PMBUS)            += pmbus_core.o
+obj-$(CONFIG_SENSORS_PMBUS)    += pmbus.o
+
 ifeq ($(CONFIG_HWMON_DEBUG_CHIP),y)
 EXTRA_CFLAGS += -DDEBUG
 endif
diff --git a/drivers/hwmon/pmbus.c b/drivers/hwmon/pmbus.c
new file mode 100644 (file)
index 0000000..98e2e28
--- /dev/null
@@ -0,0 +1,203 @@
+/*
+ * Hardware monitoring driver for PMBus devices
+ *
+ * Copyright (c) 2010, 2011 Ericsson AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/i2c.h>
+#include "pmbus.h"
+
+/*
+ * Find sensor groups and status registers on each page.
+ */
+static void pmbus_find_sensor_groups(struct i2c_client *client,
+                                    struct pmbus_driver_info *info)
+{
+       int page;
+
+       /* Sensors detected on page 0 only */
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN))
+               info->func[0] |= PMBUS_HAVE_VIN;
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP))
+               info->func[0] |= PMBUS_HAVE_VCAP;
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN))
+               info->func[0] |= PMBUS_HAVE_IIN;
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN))
+               info->func[0] |= PMBUS_HAVE_PIN;
+       if (info->func[0]
+           && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
+               info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
+               info->func[0] |= PMBUS_HAVE_FAN12;
+               if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
+                       info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
+       }
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
+               info->func[0] |= PMBUS_HAVE_FAN34;
+               if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
+                       info->func[0] |= PMBUS_HAVE_STATUS_FAN34;
+       }
+       if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1)) {
+               info->func[0] |= PMBUS_HAVE_TEMP;
+               if (pmbus_check_byte_register(client, 0,
+                                             PMBUS_STATUS_TEMPERATURE))
+                       info->func[0] |= PMBUS_HAVE_STATUS_TEMP;
+       }
+
+       /* Sensors detected on all pages */
+       for (page = 0; page < info->pages; page++) {
+               if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) {
+                       info->func[page] |= PMBUS_HAVE_VOUT;
+                       if (pmbus_check_byte_register(client, page,
+                                                     PMBUS_STATUS_VOUT))
+                               info->func[page] |= PMBUS_HAVE_STATUS_VOUT;
+               }
+               if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) {
+                       info->func[page] |= PMBUS_HAVE_IOUT;
+                       if (pmbus_check_byte_register(client, 0,
+                                                     PMBUS_STATUS_IOUT))
+                               info->func[page] |= PMBUS_HAVE_STATUS_IOUT;
+               }
+               if (pmbus_check_word_register(client, page, PMBUS_READ_POUT))
+                       info->func[page] |= PMBUS_HAVE_POUT;
+       }
+}
+
+/*
+ * Identify chip parameters.
+ */
+static int pmbus_identify(struct i2c_client *client,
+                         struct pmbus_driver_info *info)
+{
+       if (!info->pages) {
+               /*
+                * Check if the PAGE command is supported. If it is,
+                * keep setting the page number until it fails or until the
+                * maximum number of pages has been reached. Assume that
+                * this is the number of pages supported by the chip.
+                */
+               if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) {
+                       int page;
+
+                       for (page = 1; page < PMBUS_PAGES; page++) {
+                               if (pmbus_set_page(client, page) < 0)
+                                       break;
+                       }
+                       pmbus_set_page(client, 0);
+                       info->pages = page;
+               } else {
+                       info->pages = 1;
+               }
+       }
+
+       /*
+        * We should check if the COEFFICIENTS register is supported.
+        * If it is, and the chip is configured for direct mode, we can read
+        * the coefficients from the chip, one set per group of sensor
+        * registers.
+        *
+        * To do this, we will need access to a chip which actually supports the
+        * COEFFICIENTS command, since the command is too complex to implement
+        * without testing it.
+        */
+
+       /* Try to find sensor groups  */
+       pmbus_find_sensor_groups(client, info);
+
+       return 0;
+}
+
+static int pmbus_probe(struct i2c_client *client,
+                      const struct i2c_device_id *id)
+{
+       struct pmbus_driver_info *info;
+       int ret;
+
+       info = kzalloc(sizeof(struct pmbus_driver_info), GFP_KERNEL);
+       if (!info)
+               return -ENOMEM;
+
+       info->pages = id->driver_data;
+       info->identify = pmbus_identify;
+
+       ret = pmbus_do_probe(client, id, info);
+       if (ret < 0)
+               goto out;
+       return 0;
+
+out:
+       kfree(info);
+       return ret;
+}
+
+static int pmbus_remove(struct i2c_client *client)
+{
+       int ret;
+       const struct pmbus_driver_info *info;
+
+       info = pmbus_get_driver_info(client);
+       ret = pmbus_do_remove(client);
+       kfree(info);
+       return ret;
+}
+
+/*
+ * Use driver_data to set the number of pages supported by the chip.
+ */
+static const struct i2c_device_id pmbus_id[] = {
+       {"bmr450", 1},
+       {"bmr451", 1},
+       {"bmr453", 1},
+       {"bmr454", 1},
+       {"ltc2978", 8},
+       {"pmbus", 0},
+       {}
+};
+
+MODULE_DEVICE_TABLE(i2c, pmbus_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver pmbus_driver = {
+       .driver = {
+                  .name = "pmbus",
+                  },
+       .probe = pmbus_probe,
+       .remove = pmbus_remove,
+       .id_table = pmbus_id,
+};
+
+static int __init pmbus_init(void)
+{
+       return i2c_add_driver(&pmbus_driver);
+}
+
+static void __exit pmbus_exit(void)
+{
+       i2c_del_driver(&pmbus_driver);
+}
+
+MODULE_AUTHOR("Guenter Roeck");
+MODULE_DESCRIPTION("Generic PMBus driver");
+MODULE_LICENSE("GPL");
+module_init(pmbus_init);
+module_exit(pmbus_exit);
diff --git a/drivers/hwmon/pmbus.h b/drivers/hwmon/pmbus.h
new file mode 100644 (file)
index 0000000..a81f7f2
--- /dev/null
@@ -0,0 +1,313 @@
+/*
+ * pmbus.h - Common defines and structures for PMBus devices
+ *
+ * Copyright (c) 2010, 2011 Ericsson AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef PMBUS_H
+#define PMBUS_H
+
+/*
+ * Registers
+ */
+#define PMBUS_PAGE                     0x00
+#define PMBUS_OPERATION                        0x01
+#define PMBUS_ON_OFF_CONFIG            0x02
+#define PMBUS_CLEAR_FAULTS             0x03
+#define PMBUS_PHASE                    0x04
+
+#define PMBUS_CAPABILITY               0x19
+#define PMBUS_QUERY                    0x1A
+
+#define PMBUS_VOUT_MODE                        0x20
+#define PMBUS_VOUT_COMMAND             0x21
+#define PMBUS_VOUT_TRIM                        0x22
+#define PMBUS_VOUT_CAL_OFFSET          0x23
+#define PMBUS_VOUT_MAX                 0x24
+#define PMBUS_VOUT_MARGIN_HIGH         0x25
+#define PMBUS_VOUT_MARGIN_LOW          0x26
+#define PMBUS_VOUT_TRANSITION_RATE     0x27
+#define PMBUS_VOUT_DROOP               0x28
+#define PMBUS_VOUT_SCALE_LOOP          0x29
+#define PMBUS_VOUT_SCALE_MONITOR       0x2A
+
+#define PMBUS_COEFFICIENTS             0x30
+#define PMBUS_POUT_MAX                 0x31
+
+#define PMBUS_FAN_CONFIG_12            0x3A
+#define PMBUS_FAN_COMMAND_1            0x3B
+#define PMBUS_FAN_COMMAND_2            0x3C
+#define PMBUS_FAN_CONFIG_34            0x3D
+#define PMBUS_FAN_COMMAND_3            0x3E
+#define PMBUS_FAN_COMMAND_4            0x3F
+
+#define PMBUS_VOUT_OV_FAULT_LIMIT      0x40
+#define PMBUS_VOUT_OV_FAULT_RESPONSE   0x41
+#define PMBUS_VOUT_OV_WARN_LIMIT       0x42
+#define PMBUS_VOUT_UV_WARN_LIMIT       0x43
+#define PMBUS_VOUT_UV_FAULT_LIMIT      0x44
+#define PMBUS_VOUT_UV_FAULT_RESPONSE   0x45
+#define PMBUS_IOUT_OC_FAULT_LIMIT      0x46
+#define PMBUS_IOUT_OC_FAULT_RESPONSE   0x47
+#define PMBUS_IOUT_OC_LV_FAULT_LIMIT   0x48
+#define PMBUS_IOUT_OC_LV_FAULT_RESPONSE        0x49
+#define PMBUS_IOUT_OC_WARN_LIMIT       0x4A
+#define PMBUS_IOUT_UC_FAULT_LIMIT      0x4B
+#define PMBUS_IOUT_UC_FAULT_RESPONSE   0x4C
+
+#define PMBUS_OT_FAULT_LIMIT           0x4F
+#define PMBUS_OT_FAULT_RESPONSE                0x50
+#define PMBUS_OT_WARN_LIMIT            0x51
+#define PMBUS_UT_WARN_LIMIT            0x52
+#define PMBUS_UT_FAULT_LIMIT           0x53
+#define PMBUS_UT_FAULT_RESPONSE                0x54
+#define PMBUS_VIN_OV_FAULT_LIMIT       0x55
+#define PMBUS_VIN_OV_FAULT_RESPONSE    0x56
+#define PMBUS_VIN_OV_WARN_LIMIT                0x57
+#define PMBUS_VIN_UV_WARN_LIMIT                0x58
+#define PMBUS_VIN_UV_FAULT_LIMIT       0x59
+
+#define PMBUS_IIN_OC_FAULT_LIMIT       0x5B
+#define PMBUS_IIN_OC_WARN_LIMIT                0x5D
+
+#define PMBUS_POUT_OP_FAULT_LIMIT      0x68
+#define PMBUS_POUT_OP_WARN_LIMIT       0x6A
+#define PMBUS_PIN_OP_WARN_LIMIT                0x6B
+
+#define PMBUS_STATUS_BYTE              0x78
+#define PMBUS_STATUS_WORD              0x79
+#define PMBUS_STATUS_VOUT              0x7A
+#define PMBUS_STATUS_IOUT              0x7B
+#define PMBUS_STATUS_INPUT             0x7C
+#define PMBUS_STATUS_TEMPERATURE       0x7D
+#define PMBUS_STATUS_CML               0x7E
+#define PMBUS_STATUS_OTHER             0x7F
+#define PMBUS_STATUS_MFR_SPECIFIC      0x80
+#define PMBUS_STATUS_FAN_12            0x81
+#define PMBUS_STATUS_FAN_34            0x82
+
+#define PMBUS_READ_VIN                 0x88
+#define PMBUS_READ_IIN                 0x89
+#define PMBUS_READ_VCAP                        0x8A
+#define PMBUS_READ_VOUT                        0x8B
+#define PMBUS_READ_IOUT                        0x8C
+#define PMBUS_READ_TEMPERATURE_1       0x8D
+#define PMBUS_READ_TEMPERATURE_2       0x8E
+#define PMBUS_READ_TEMPERATURE_3       0x8F
+#define PMBUS_READ_FAN_SPEED_1         0x90
+#define PMBUS_READ_FAN_SPEED_2         0x91
+#define PMBUS_READ_FAN_SPEED_3         0x92
+#define PMBUS_READ_FAN_SPEED_4         0x93
+#define PMBUS_READ_DUTY_CYCLE          0x94
+#define PMBUS_READ_FREQUENCY           0x95
+#define PMBUS_READ_POUT                        0x96
+#define PMBUS_READ_PIN                 0x97
+
+#define PMBUS_REVISION                 0x98
+#define PMBUS_MFR_ID                   0x99
+#define PMBUS_MFR_MODEL                        0x9A
+#define PMBUS_MFR_REVISION             0x9B
+#define PMBUS_MFR_LOCATION             0x9C
+#define PMBUS_MFR_DATE                 0x9D
+#define PMBUS_MFR_SERIAL               0x9E
+
+/*
+ * CAPABILITY
+ */
+#define PB_CAPABILITY_SMBALERT         (1<<4)
+#define PB_CAPABILITY_ERROR_CHECK      (1<<7)
+
+/*
+ * VOUT_MODE
+ */
+#define PB_VOUT_MODE_MODE_MASK         0xe0
+#define PB_VOUT_MODE_PARAM_MASK                0x1f
+
+#define PB_VOUT_MODE_LINEAR            0x00
+#define PB_VOUT_MODE_VID               0x20
+#define PB_VOUT_MODE_DIRECT            0x40
+
+/*
+ * Fan configuration
+ */
+#define PB_FAN_2_PULSE_MASK            ((1 << 0) | (1 << 1))
+#define PB_FAN_2_RPM                   (1 << 2)
+#define PB_FAN_2_INSTALLED             (1 << 3)
+#define PB_FAN_1_PULSE_MASK            ((1 << 4) | (1 << 5))
+#define PB_FAN_1_RPM                   (1 << 6)
+#define PB_FAN_1_INSTALLED             (1 << 7)
+
+/*
+ * STATUS_BYTE, STATUS_WORD (lower)
+ */
+#define PB_STATUS_NONE_ABOVE           (1<<0)
+#define PB_STATUS_CML                  (1<<1)
+#define PB_STATUS_TEMPERATURE          (1<<2)
+#define PB_STATUS_VIN_UV               (1<<3)
+#define PB_STATUS_IOUT_OC              (1<<4)
+#define PB_STATUS_VOUT_OV              (1<<5)
+#define PB_STATUS_OFF                  (1<<6)
+#define PB_STATUS_BUSY                 (1<<7)
+
+/*
+ * STATUS_WORD (upper)
+ */
+#define PB_STATUS_UNKNOWN              (1<<8)
+#define PB_STATUS_OTHER                        (1<<9)
+#define PB_STATUS_FANS                 (1<<10)
+#define PB_STATUS_POWER_GOOD_N         (1<<11)
+#define PB_STATUS_WORD_MFR             (1<<12)
+#define PB_STATUS_INPUT                        (1<<13)
+#define PB_STATUS_IOUT_POUT            (1<<14)
+#define PB_STATUS_VOUT                 (1<<15)
+
+/*
+ * STATUS_IOUT
+ */
+#define PB_POUT_OP_WARNING             (1<<0)
+#define PB_POUT_OP_FAULT               (1<<1)
+#define PB_POWER_LIMITING              (1<<2)
+#define PB_CURRENT_SHARE_FAULT         (1<<3)
+#define PB_IOUT_UC_FAULT               (1<<4)
+#define PB_IOUT_OC_WARNING             (1<<5)
+#define PB_IOUT_OC_LV_FAULT            (1<<6)
+#define PB_IOUT_OC_FAULT               (1<<7)
+
+/*
+ * STATUS_VOUT, STATUS_INPUT
+ */
+#define PB_VOLTAGE_UV_FAULT            (1<<4)
+#define PB_VOLTAGE_UV_WARNING          (1<<5)
+#define PB_VOLTAGE_OV_WARNING          (1<<6)
+#define PB_VOLTAGE_OV_FAULT            (1<<7)
+
+/*
+ * STATUS_INPUT
+ */
+#define PB_PIN_OP_WARNING              (1<<0)
+#define PB_IIN_OC_WARNING              (1<<1)
+#define PB_IIN_OC_FAULT                        (1<<2)
+
+/*
+ * STATUS_TEMPERATURE
+ */
+#define PB_TEMP_UT_FAULT               (1<<4)
+#define PB_TEMP_UT_WARNING             (1<<5)
+#define PB_TEMP_OT_WARNING             (1<<6)
+#define PB_TEMP_OT_FAULT               (1<<7)
+
+/*
+ * STATUS_FAN
+ */
+#define PB_FAN_AIRFLOW_WARNING         (1<<0)
+#define PB_FAN_AIRFLOW_FAULT           (1<<1)
+#define PB_FAN_FAN2_SPEED_OVERRIDE     (1<<2)
+#define PB_FAN_FAN1_SPEED_OVERRIDE     (1<<3)
+#define PB_FAN_FAN2_WARNING            (1<<4)
+#define PB_FAN_FAN1_WARNING            (1<<5)
+#define PB_FAN_FAN2_FAULT              (1<<6)
+#define PB_FAN_FAN1_FAULT              (1<<7)
+
+/*
+ * CML_FAULT_STATUS
+ */
+#define PB_CML_FAULT_OTHER_MEM_LOGIC   (1<<0)
+#define PB_CML_FAULT_OTHER_COMM                (1<<1)
+#define PB_CML_FAULT_PROCESSOR         (1<<3)
+#define PB_CML_FAULT_MEMORY            (1<<4)
+#define PB_CML_FAULT_PACKET_ERROR      (1<<5)
+#define PB_CML_FAULT_INVALID_DATA      (1<<6)
+#define PB_CML_FAULT_INVALID_COMMAND   (1<<7)
+
+enum pmbus_sensor_classes {
+       PSC_VOLTAGE_IN = 0,
+       PSC_VOLTAGE_OUT,
+       PSC_CURRENT_IN,
+       PSC_CURRENT_OUT,
+       PSC_POWER,
+       PSC_TEMPERATURE,
+       PSC_FAN,
+       PSC_NUM_CLASSES         /* Number of power sensor classes */
+};
+
+#define PMBUS_PAGES    32      /* Per PMBus specification */
+
+/* Functionality bit mask */
+#define PMBUS_HAVE_VIN         (1 << 0)
+#define PMBUS_HAVE_VCAP                (1 << 1)
+#define PMBUS_HAVE_VOUT                (1 << 2)
+#define PMBUS_HAVE_IIN         (1 << 3)
+#define PMBUS_HAVE_IOUT                (1 << 4)
+#define PMBUS_HAVE_PIN         (1 << 5)
+#define PMBUS_HAVE_POUT                (1 << 6)
+#define PMBUS_HAVE_FAN12       (1 << 7)
+#define PMBUS_HAVE_FAN34       (1 << 8)
+#define PMBUS_HAVE_TEMP                (1 << 9)
+#define PMBUS_HAVE_TEMP2       (1 << 10)
+#define PMBUS_HAVE_TEMP3       (1 << 11)
+#define PMBUS_HAVE_STATUS_VOUT (1 << 12)
+#define PMBUS_HAVE_STATUS_IOUT (1 << 13)
+#define PMBUS_HAVE_STATUS_INPUT        (1 << 14)
+#define PMBUS_HAVE_STATUS_TEMP (1 << 15)
+#define PMBUS_HAVE_STATUS_FAN12        (1 << 16)
+#define PMBUS_HAVE_STATUS_FAN34        (1 << 17)
+
+struct pmbus_driver_info {
+       int pages;              /* Total number of pages */
+       bool direct[PSC_NUM_CLASSES];
+                               /* true if device uses direct data format
+                                  for the given sensor class */
+       /*
+        * Support one set of coefficients for each sensor type
+        * Used for chips providing data in direct mode.
+        */
+       int m[PSC_NUM_CLASSES]; /* mantissa for direct data format */
+       int b[PSC_NUM_CLASSES]; /* offset */
+       int R[PSC_NUM_CLASSES]; /* exponent */
+
+       u32 func[PMBUS_PAGES];  /* Functionality, per page */
+       /*
+        * The get_status function maps manufacturing specific status values
+        * into PMBus standard status values.
+        * This function is optional and only necessary if chip specific status
+        * register values have to be mapped into standard PMBus status register
+        * values.
+        */
+       int (*get_status)(struct i2c_client *client, int page, int reg);
+       /*
+        * The identify function determines supported PMBus functionality.
+        * This function is only necessary if a chip driver supports multiple
+        * chips, and the chip functionality is not pre-determined.
+        */
+       int (*identify)(struct i2c_client *client,
+                       struct pmbus_driver_info *info);
+};
+
+/* Function declarations */
+
+int pmbus_set_page(struct i2c_client *client, u8 page);
+int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg);
+void pmbus_clear_faults(struct i2c_client *client);
+bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg);
+bool pmbus_check_word_register(struct i2c_client *client, int page, int reg);
+int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
+                  struct pmbus_driver_info *info);
+int pmbus_do_remove(struct i2c_client *client);
+const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client
+                                                     *client);
+
+#endif /* PMBUS_H */
diff --git a/drivers/hwmon/pmbus_core.c b/drivers/hwmon/pmbus_core.c
new file mode 100644 (file)
index 0000000..0edab1c
--- /dev/null
@@ -0,0 +1,1628 @@
+/*
+ * Hardware monitoring driver for PMBus devices
+ *
+ * Copyright (c) 2010, 2011 Ericsson AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/delay.h>
+#include <linux/i2c/pmbus.h>
+#include "pmbus.h"
+
+/*
+ * Constants needed to determine number of sensors, booleans, and labels.
+ */
+#define PMBUS_MAX_INPUT_SENSORS                11      /* 6*volt, 3*curr, 2*power */
+#define PMBUS_VOUT_SENSORS_PER_PAGE    5       /* input, min, max, lcrit,
+                                                  crit */
+#define PMBUS_IOUT_SENSORS_PER_PAGE    4       /* input, min, max, crit */
+#define PMBUS_POUT_SENSORS_PER_PAGE    4       /* input, cap, max, crit */
+#define PMBUS_MAX_SENSORS_PER_FAN      1       /* input */
+#define PMBUS_MAX_SENSORS_PER_TEMP     5       /* input, min, max, lcrit,
+                                                  crit */
+
+#define PMBUS_MAX_INPUT_BOOLEANS       7       /* v: min_alarm, max_alarm,
+                                                  lcrit_alarm, crit_alarm;
+                                                  c: alarm, crit_alarm;
+                                                  p: crit_alarm */
+#define PMBUS_VOUT_BOOLEANS_PER_PAGE   4       /* min_alarm, max_alarm,
+                                                  lcrit_alarm, crit_alarm */
+#define PMBUS_IOUT_BOOLEANS_PER_PAGE   3       /* alarm, lcrit_alarm,
+                                                  crit_alarm */
+#define PMBUS_POUT_BOOLEANS_PER_PAGE   2       /* alarm, crit_alarm */
+#define PMBUS_MAX_BOOLEANS_PER_FAN     2       /* alarm, fault */
+#define PMBUS_MAX_BOOLEANS_PER_TEMP    4       /* min_alarm, max_alarm,
+                                                  lcrit_alarm, crit_alarm */
+
+#define PMBUS_MAX_INPUT_LABELS         4       /* vin, vcap, iin, pin */
+
+/*
+ * status, status_vout, status_iout, status_fans, and status_temp
+ * are paged. status_input and status_fan34 are unpaged.
+ * status_fan34 is a special case to handle a second set of fans
+ * on page 0.
+ */
+#define PB_NUM_STATUS_REG      (PMBUS_PAGES * 5 + 2)
+
+/*
+ * Index into status register array, per status register group
+ */
+#define PB_STATUS_BASE         0
+#define PB_STATUS_VOUT_BASE    (PB_STATUS_BASE + PMBUS_PAGES)
+#define PB_STATUS_IOUT_BASE    (PB_STATUS_VOUT_BASE + PMBUS_PAGES)
+#define PB_STATUS_FAN_BASE     (PB_STATUS_IOUT_BASE + PMBUS_PAGES)
+#define PB_STATUS_FAN34_BASE   (PB_STATUS_FAN_BASE + PMBUS_PAGES)
+#define PB_STATUS_INPUT_BASE   (PB_STATUS_FAN34_BASE + 1)
+#define PB_STATUS_TEMP_BASE    (PB_STATUS_INPUT_BASE + 1)
+
+struct pmbus_sensor {
+       char name[I2C_NAME_SIZE];       /* sysfs sensor name */
+       struct sensor_device_attribute attribute;
+       u8 page;                /* page number */
+       u8 reg;                 /* register */
+       enum pmbus_sensor_classes class;        /* sensor class */
+       bool update;            /* runtime sensor update needed */
+       int data;               /* Sensor data.
+                                  Negative if there was a read error */
+};
+
+struct pmbus_boolean {
+       char name[I2C_NAME_SIZE];       /* sysfs boolean name */
+       struct sensor_device_attribute attribute;
+};
+
+struct pmbus_label {
+       char name[I2C_NAME_SIZE];       /* sysfs label name */
+       struct sensor_device_attribute attribute;
+       char label[I2C_NAME_SIZE];      /* label */
+};
+
+struct pmbus_data {
+       struct device *hwmon_dev;
+
+       u32 flags;              /* from platform data */
+
+       int exponent;           /* linear mode: exponent for output voltages */
+
+       const struct pmbus_driver_info *info;
+
+       int max_attributes;
+       int num_attributes;
+       struct attribute **attributes;
+       struct attribute_group group;
+
+       /*
+        * Sensors cover both sensor and limit registers.
+        */
+       int max_sensors;
+       int num_sensors;
+       struct pmbus_sensor *sensors;
+       /*
+        * Booleans are used for alarms.
+        * Values are determined from status registers.
+        */
+       int max_booleans;
+       int num_booleans;
+       struct pmbus_boolean *booleans;
+       /*
+        * Labels are used to map generic names (e.g., "in1")
+        * to PMBus specific names (e.g., "vin" or "vout1").
+        */
+       int max_labels;
+       int num_labels;
+       struct pmbus_label *labels;
+
+       struct mutex update_lock;
+       bool valid;
+       unsigned long last_updated;     /* in jiffies */
+
+       /*
+        * A single status register covers multiple attributes,
+        * so we keep them all together.
+        */
+       u8 status_bits;
+       u8 status[PB_NUM_STATUS_REG];
+
+       u8 currpage;
+};
+
+int pmbus_set_page(struct i2c_client *client, u8 page)
+{
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       int rv = 0;
+       int newpage;
+
+       if (page != data->currpage) {
+               rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
+               newpage = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
+               if (newpage != page)
+                       rv = -EINVAL;
+               else
+                       data->currpage = page;
+       }
+       return rv;
+}
+EXPORT_SYMBOL_GPL(pmbus_set_page);
+
+static int pmbus_write_byte(struct i2c_client *client, u8 page, u8 value)
+{
+       int rv;
+
+       rv = pmbus_set_page(client, page);
+       if (rv < 0)
+               return rv;
+
+       return i2c_smbus_write_byte(client, value);
+}
+
+static int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg,
+                                u16 word)
+{
+       int rv;
+
+       rv = pmbus_set_page(client, page);
+       if (rv < 0)
+               return rv;
+
+       return i2c_smbus_write_word_data(client, reg, word);
+}
+
+int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg)
+{
+       int rv;
+
+       rv = pmbus_set_page(client, page);
+       if (rv < 0)
+               return rv;
+
+       return i2c_smbus_read_word_data(client, reg);
+}
+EXPORT_SYMBOL_GPL(pmbus_read_word_data);
+
+static int pmbus_read_byte_data(struct i2c_client *client, u8 page, u8 reg)
+{
+       int rv;
+
+       rv = pmbus_set_page(client, page);
+       if (rv < 0)
+               return rv;
+
+       return i2c_smbus_read_byte_data(client, reg);
+}
+
+static void pmbus_clear_fault_page(struct i2c_client *client, int page)
+{
+       pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
+}
+
+void pmbus_clear_faults(struct i2c_client *client)
+{
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       int i;
+
+       for (i = 0; i < data->info->pages; i++)
+               pmbus_clear_fault_page(client, i);
+}
+EXPORT_SYMBOL_GPL(pmbus_clear_faults);
+
+static int pmbus_check_status_cml(struct i2c_client *client, int page)
+{
+       int status, status2;
+
+       status = pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
+       if (status < 0 || (status & PB_STATUS_CML)) {
+               status2 = pmbus_read_byte_data(client, page, PMBUS_STATUS_CML);
+               if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
+                       return -EINVAL;
+       }
+       return 0;
+}
+
+bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
+{
+       int rv;
+       struct pmbus_data *data = i2c_get_clientdata(client);
+
+       rv = pmbus_read_byte_data(client, page, reg);
+       if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+               rv = pmbus_check_status_cml(client, page);
+       pmbus_clear_fault_page(client, page);
+       return rv >= 0;
+}
+EXPORT_SYMBOL_GPL(pmbus_check_byte_register);
+
+bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
+{
+       int rv;
+       struct pmbus_data *data = i2c_get_clientdata(client);
+
+       rv = pmbus_read_word_data(client, page, reg);
+       if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+               rv = pmbus_check_status_cml(client, page);
+       pmbus_clear_fault_page(client, page);
+       return rv >= 0;
+}
+EXPORT_SYMBOL_GPL(pmbus_check_word_register);
+
+const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
+{
+       struct pmbus_data *data = i2c_get_clientdata(client);
+
+       return data->info;
+}
+EXPORT_SYMBOL_GPL(pmbus_get_driver_info);
+
+static int pmbus_get_status(struct i2c_client *client, int page, int reg)
+{
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       const struct pmbus_driver_info *info = data->info;
+       int status;
+
+       if (info->get_status) {
+               status = info->get_status(client, page, reg);
+               if (status != -ENODATA)
+                       return status;
+       }
+       return  pmbus_read_byte_data(client, page, reg);
+}
+
+static struct pmbus_data *pmbus_update_device(struct device *dev)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       const struct pmbus_driver_info *info = data->info;
+
+       mutex_lock(&data->update_lock);
+       if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+               int i;
+
+               for (i = 0; i < info->pages; i++)
+                       data->status[PB_STATUS_BASE + i]
+                           = pmbus_read_byte_data(client, i,
+                                                  PMBUS_STATUS_BYTE);
+               for (i = 0; i < info->pages; i++) {
+                       if (!(info->func[i] & PMBUS_HAVE_STATUS_VOUT))
+                               continue;
+                       data->status[PB_STATUS_VOUT_BASE + i]
+                         = pmbus_get_status(client, i, PMBUS_STATUS_VOUT);
+               }
+               for (i = 0; i < info->pages; i++) {
+                       if (!(info->func[i] & PMBUS_HAVE_STATUS_IOUT))
+                               continue;
+                       data->status[PB_STATUS_IOUT_BASE + i]
+                         = pmbus_get_status(client, i, PMBUS_STATUS_IOUT);
+               }
+               for (i = 0; i < info->pages; i++) {
+                       if (!(info->func[i] & PMBUS_HAVE_STATUS_TEMP))
+                               continue;
+                       data->status[PB_STATUS_TEMP_BASE + i]
+                         = pmbus_get_status(client, i,
+                                            PMBUS_STATUS_TEMPERATURE);
+               }
+               for (i = 0; i < info->pages; i++) {
+                       if (!(info->func[i] & PMBUS_HAVE_STATUS_FAN12))
+                               continue;
+                       data->status[PB_STATUS_FAN_BASE + i]
+                         = pmbus_get_status(client, i, PMBUS_STATUS_FAN_12);
+               }
+
+               if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
+                       data->status[PB_STATUS_INPUT_BASE]
+                         = pmbus_get_status(client, 0, PMBUS_STATUS_INPUT);
+
+               if (info->func[0] & PMBUS_HAVE_STATUS_FAN34)
+                       data->status[PB_STATUS_FAN34_BASE]
+                         = pmbus_get_status(client, 0, PMBUS_STATUS_FAN_34);
+
+               for (i = 0; i < data->num_sensors; i++) {
+                       struct pmbus_sensor *sensor = &data->sensors[i];
+
+                       if (!data->valid || sensor->update)
+                               sensor->data
+                                   = pmbus_read_word_data(client, sensor->page,
+                                                          sensor->reg);
+               }
+               pmbus_clear_faults(client);
+               data->last_updated = jiffies;
+               data->valid = 1;
+       }
+       mutex_unlock(&data->update_lock);
+       return data;
+}
+
+/*
+ * Convert linear sensor values to milli- or micro-units
+ * depending on sensor type.
+ */
+static int pmbus_reg2data_linear(struct pmbus_data *data,
+                                struct pmbus_sensor *sensor)
+{
+       s16 exponent, mantissa;
+       long val;
+
+       if (sensor->class == PSC_VOLTAGE_OUT) {
+               exponent = data->exponent;
+               mantissa = (s16) sensor->data;
+       } else {
+               exponent = (sensor->data >> 11) & 0x001f;
+               mantissa = sensor->data & 0x07ff;
+
+               if (exponent > 0x0f)
+                       exponent |= 0xffe0;     /* sign extend exponent */
+               if (mantissa > 0x03ff)
+                       mantissa |= 0xf800;     /* sign extend mantissa */
+       }
+
+       val = mantissa;
+
+       /* scale result to milli-units for all sensors except fans */
+       if (sensor->class != PSC_FAN)
+               val = val * 1000L;
+
+       /* scale result to micro-units for power sensors */
+       if (sensor->class == PSC_POWER)
+               val = val * 1000L;
+
+       if (exponent >= 0)
+               val <<= exponent;
+       else
+               val >>= -exponent;
+
+       return (int)val;
+}
+
+/*
+ * Convert direct sensor values to milli- or micro-units
+ * depending on sensor type.
+ */
+static int pmbus_reg2data_direct(struct pmbus_data *data,
+                                struct pmbus_sensor *sensor)
+{
+       long val = (s16) sensor->data;
+       long m, b, R;
+
+       m = data->info->m[sensor->class];
+       b = data->info->b[sensor->class];
+       R = data->info->R[sensor->class];
+
+       if (m == 0)
+               return 0;
+
+       /* X = 1/m * (Y * 10^-R - b) */
+       R = -R;
+       /* scale result to milli-units for everything but fans */
+       if (sensor->class != PSC_FAN) {
+               R += 3;
+               b *= 1000;
+       }
+
+       /* scale result to micro-units for power sensors */
+       if (sensor->class == PSC_POWER) {
+               R += 3;
+               b *= 1000;
+       }
+
+       while (R > 0) {
+               val *= 10;
+               R--;
+       }
+       while (R < 0) {
+               val = DIV_ROUND_CLOSEST(val, 10);
+               R++;
+       }
+
+       return (int)((val - b) / m);
+}
+
+static int pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
+{
+       int val;
+
+       if (data->info->direct[sensor->class])
+               val = pmbus_reg2data_direct(data, sensor);
+       else
+               val = pmbus_reg2data_linear(data, sensor);
+
+       return val;
+}
+
+#define MAX_MANTISSA   (1023 * 1000)
+#define MIN_MANTISSA   (511 * 1000)
+
+static u16 pmbus_data2reg_linear(struct pmbus_data *data,
+                                enum pmbus_sensor_classes class, long val)
+{
+       s16 exponent = 0, mantissa = 0;
+       bool negative = false;
+
+       /* simple case */
+       if (val == 0)
+               return 0;
+
+       if (val < 0) {
+               negative = true;
+               val = -val;
+       }
+
+       if (class == PSC_VOLTAGE_OUT) {
+               /*
+                * For a static exponents, we don't have a choice
+                * but to adjust the value to it.
+                */
+               if (data->exponent < 0)
+                       val <<= -data->exponent;
+               else
+                       val >>= data->exponent;
+               val = DIV_ROUND_CLOSEST(val, 1000);
+               if (val > 0x7fff)
+                       val = 0x7fff;
+               return negative ? -val : val;
+       }
+
+       /* Power is in uW. Convert to mW before converting. */
+       if (class == PSC_POWER)
+               val = DIV_ROUND_CLOSEST(val, 1000L);
+
+       /*
+        * For simplicity, convert fan data to milli-units
+        * before calculating the exponent.
+        */
+       if (class == PSC_FAN)
+               val = val * 1000;
+
+       /* Reduce large mantissa until it fits into 10 bit */
+       while (val >= MAX_MANTISSA && exponent < 15) {
+               exponent++;
+               val >>= 1;
+       }
+       /* Increase small mantissa to improve precision */
+       while (val < MIN_MANTISSA && exponent > -15) {
+               exponent--;
+               val <<= 1;
+       }
+
+       /* Convert mantissa from milli-units to units */
+       mantissa = DIV_ROUND_CLOSEST(val, 1000);
+
+       /* Ensure that resulting number is within range */
+       if (mantissa > 0x3ff)
+               mantissa = 0x3ff;
+
+       /* restore sign */
+       if (negative)
+               mantissa = -mantissa;
+
+       /* Convert to 5 bit exponent, 11 bit mantissa */
+       return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
+}
+
+static u16 pmbus_data2reg_direct(struct pmbus_data *data,
+                                enum pmbus_sensor_classes class, long val)
+{
+       long m, b, R;
+
+       m = data->info->m[class];
+       b = data->info->b[class];
+       R = data->info->R[class];
+
+       /* Power is in uW. Adjust R and b. */
+       if (class == PSC_POWER) {
+               R -= 3;
+               b *= 1000;
+       }
+
+       /* Calculate Y = (m * X + b) * 10^R */
+       if (class != PSC_FAN) {
+               R -= 3;         /* Adjust R and b for data in milli-units */
+               b *= 1000;
+       }
+       val = val * m + b;
+
+       while (R > 0) {
+               val *= 10;
+               R--;
+       }
+       while (R < 0) {
+               val = DIV_ROUND_CLOSEST(val, 10);
+               R++;
+       }
+
+       return val;
+}
+
+static u16 pmbus_data2reg(struct pmbus_data *data,
+                         enum pmbus_sensor_classes class, long val)
+{
+       u16 regval;
+
+       if (data->info->direct[class])
+               regval = pmbus_data2reg_direct(data, class, val);
+       else
+               regval = pmbus_data2reg_linear(data, class, val);
+
+       return regval;
+}
+
+/*
+ * Return boolean calculated from converted data.
+ * <index> defines a status register index and mask, and optionally
+ * two sensor indexes.
+ * The upper half-word references the two sensors,
+ * two sensor indices.
+ * The upper half-word references the two optional sensors,
+ * the lower half word references status register and mask.
+ * The function returns true if (status[reg] & mask) is true and,
+ * if specified, if v1 >= v2.
+ * To determine if an object exceeds upper limits, specify <v, limit>.
+ * To determine if an object exceeds lower limits, specify <limit, v>.
+ *
+ * For booleans created with pmbus_add_boolean_reg(), only the lower 16 bits of
+ * index are set. s1 and s2 (the sensor index values) are zero in this case.
+ * The function returns true if (status[reg] & mask) is true.
+ *
+ * If the boolean was created with pmbus_add_boolean_cmp(), a comparison against
+ * a specified limit has to be performed to determine the boolean result.
+ * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
+ * sensor values referenced by sensor indices s1 and s2).
+ *
+ * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
+ * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
+ *
+ * If a negative value is stored in any of the referenced registers, this value
+ * reflects an error code which will be returned.
+ */
+static int pmbus_get_boolean(struct pmbus_data *data, int index, int *val)
+{
+       u8 s1 = (index >> 24) & 0xff;
+       u8 s2 = (index >> 16) & 0xff;
+       u8 reg = (index >> 8) & 0xff;
+       u8 mask = index & 0xff;
+       int status;
+       u8 regval;
+
+       status = data->status[reg];
+       if (status < 0)
+               return status;
+
+       regval = status & mask;
+       if (!s1 && !s2)
+               *val = !!regval;
+       else {
+               int v1, v2;
+               struct pmbus_sensor *sensor1, *sensor2;
+
+               sensor1 = &data->sensors[s1];
+               if (sensor1->data < 0)
+                       return sensor1->data;
+               sensor2 = &data->sensors[s2];
+               if (sensor2->data < 0)
+                       return sensor2->data;
+
+               v1 = pmbus_reg2data(data, sensor1);
+               v2 = pmbus_reg2data(data, sensor2);
+               *val = !!(regval && v1 >= v2);
+       }
+       return 0;
+}
+
+static ssize_t pmbus_show_boolean(struct device *dev,
+                                 struct device_attribute *da, char *buf)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       struct pmbus_data *data = pmbus_update_device(dev);
+       int val;
+       int err;
+
+       err = pmbus_get_boolean(data, attr->index, &val);
+       if (err)
+               return err;
+       return snprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static ssize_t pmbus_show_sensor(struct device *dev,
+                                struct device_attribute *da, char *buf)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+       struct pmbus_data *data = pmbus_update_device(dev);
+       struct pmbus_sensor *sensor;
+
+       sensor = &data->sensors[attr->index];
+       if (sensor->data < 0)
+               return sensor->data;
+
+       return snprintf(buf, PAGE_SIZE, "%d\n", pmbus_reg2data(data, sensor));
+}
+
+static ssize_t pmbus_set_sensor(struct device *dev,
+                               struct device_attribute *devattr,
+                               const char *buf, size_t count)
+{
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+       struct i2c_client *client = to_i2c_client(dev);
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       struct pmbus_sensor *sensor = &data->sensors[attr->index];
+       ssize_t rv = count;
+       long val = 0;
+       int ret;
+       u16 regval;
+
+       if (strict_strtol(buf, 10, &val) < 0)
+               return -EINVAL;
+
+       mutex_lock(&data->update_lock);
+       regval = pmbus_data2reg(data, sensor->class, val);
+       ret = pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
+       if (ret < 0)
+               rv = ret;
+       else
+               data->sensors[attr->index].data = regval;
+       mutex_unlock(&data->update_lock);
+       return rv;
+}
+
+static ssize_t pmbus_show_label(struct device *dev,
+                               struct device_attribute *da, char *buf)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+
+       return snprintf(buf, PAGE_SIZE, "%s\n",
+                       data->labels[attr->index].label);
+}
+
+#define PMBUS_ADD_ATTR(data, _name, _idx, _mode, _type, _show, _set)   \
+do {                                                                   \
+       struct sensor_device_attribute *a                               \
+           = &data->_type##s[data->num_##_type##s].attribute;          \
+       BUG_ON(data->num_attributes >= data->max_attributes);           \
+       a->dev_attr.attr.name = _name;                                  \
+       a->dev_attr.attr.mode = _mode;                                  \
+       a->dev_attr.show = _show;                                       \
+       a->dev_attr.store = _set;                                       \
+       a->index = _idx;                                                \
+       data->attributes[data->num_attributes] = &a->dev_attr.attr;     \
+       data->num_attributes++;                                         \
+} while (0)
+
+#define PMBUS_ADD_GET_ATTR(data, _name, _type, _idx)                   \
+       PMBUS_ADD_ATTR(data, _name, _idx, S_IRUGO, _type,               \
+                      pmbus_show_##_type,  NULL)
+
+#define PMBUS_ADD_SET_ATTR(data, _name, _type, _idx)                   \
+       PMBUS_ADD_ATTR(data, _name, _idx, S_IWUSR | S_IRUGO, _type,     \
+                      pmbus_show_##_type, pmbus_set_##_type)
+
+static void pmbus_add_boolean(struct pmbus_data *data,
+                             const char *name, const char *type, int seq,
+                             int idx)
+{
+       struct pmbus_boolean *boolean;
+
+       BUG_ON(data->num_booleans >= data->max_booleans);
+
+       boolean = &data->booleans[data->num_booleans];
+
+       snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
+                name, seq, type);
+       PMBUS_ADD_GET_ATTR(data, boolean->name, boolean, idx);
+       data->num_booleans++;
+}
+
+static void pmbus_add_boolean_reg(struct pmbus_data *data,
+                                 const char *name, const char *type,
+                                 int seq, int reg, int bit)
+{
+       pmbus_add_boolean(data, name, type, seq, (reg << 8) | bit);
+}
+
+static void pmbus_add_boolean_cmp(struct pmbus_data *data,
+                                 const char *name, const char *type,
+                                 int seq, int i1, int i2, int reg, int mask)
+{
+       pmbus_add_boolean(data, name, type, seq,
+                         (i1 << 24) | (i2 << 16) | (reg << 8) | mask);
+}
+
+static void pmbus_add_sensor(struct pmbus_data *data,
+                            const char *name, const char *type, int seq,
+                            int page, int reg, enum pmbus_sensor_classes class,
+                            bool update)
+{
+       struct pmbus_sensor *sensor;
+
+       BUG_ON(data->num_sensors >= data->max_sensors);
+
+       sensor = &data->sensors[data->num_sensors];
+       snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
+                name, seq, type);
+       sensor->page = page;
+       sensor->reg = reg;
+       sensor->class = class;
+       sensor->update = update;
+       if (update)
+               PMBUS_ADD_GET_ATTR(data, sensor->name, sensor,
+                                  data->num_sensors);
+       else
+               PMBUS_ADD_SET_ATTR(data, sensor->name, sensor,
+                                  data->num_sensors);
+       data->num_sensors++;
+}
+
+static void pmbus_add_label(struct pmbus_data *data,
+                           const char *name, int seq,
+                           const char *lstring, int index)
+{
+       struct pmbus_label *label;
+
+       BUG_ON(data->num_labels >= data->max_labels);
+
+       label = &data->labels[data->num_labels];
+       snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
+       if (!index)
+               strncpy(label->label, lstring, sizeof(label->label) - 1);
+       else
+               snprintf(label->label, sizeof(label->label), "%s%d", lstring,
+                        index);
+
+       PMBUS_ADD_GET_ATTR(data, label->name, label, data->num_labels);
+       data->num_labels++;
+}
+
+static const int pmbus_temp_registers[] = {
+       PMBUS_READ_TEMPERATURE_1,
+       PMBUS_READ_TEMPERATURE_2,
+       PMBUS_READ_TEMPERATURE_3
+};
+
+static const int pmbus_fan_registers[] = {
+       PMBUS_READ_FAN_SPEED_1,
+       PMBUS_READ_FAN_SPEED_2,
+       PMBUS_READ_FAN_SPEED_3,
+       PMBUS_READ_FAN_SPEED_4
+};
+
+static const int pmbus_fan_config_registers[] = {
+       PMBUS_FAN_CONFIG_12,
+       PMBUS_FAN_CONFIG_12,
+       PMBUS_FAN_CONFIG_34,
+       PMBUS_FAN_CONFIG_34
+};
+
+static const int pmbus_fan_status_registers[] = {
+       PMBUS_STATUS_FAN_12,
+       PMBUS_STATUS_FAN_12,
+       PMBUS_STATUS_FAN_34,
+       PMBUS_STATUS_FAN_34
+};
+
+/*
+ * Determine maximum number of sensors, booleans, and labels.
+ * To keep things simple, only make a rough high estimate.
+ */
+static void pmbus_find_max_attr(struct i2c_client *client,
+                               struct pmbus_data *data)
+{
+       const struct pmbus_driver_info *info = data->info;
+       int page, max_sensors, max_booleans, max_labels;
+
+       max_sensors = PMBUS_MAX_INPUT_SENSORS;
+       max_booleans = PMBUS_MAX_INPUT_BOOLEANS;
+       max_labels = PMBUS_MAX_INPUT_LABELS;
+
+       for (page = 0; page < info->pages; page++) {
+               if (info->func[page] & PMBUS_HAVE_VOUT) {
+                       max_sensors += PMBUS_VOUT_SENSORS_PER_PAGE;
+                       max_booleans += PMBUS_VOUT_BOOLEANS_PER_PAGE;
+                       max_labels++;
+               }
+               if (info->func[page] & PMBUS_HAVE_IOUT) {
+                       max_sensors += PMBUS_IOUT_SENSORS_PER_PAGE;
+                       max_booleans += PMBUS_IOUT_BOOLEANS_PER_PAGE;
+                       max_labels++;
+               }
+               if (info->func[page] & PMBUS_HAVE_POUT) {
+                       max_sensors += PMBUS_POUT_SENSORS_PER_PAGE;
+                       max_booleans += PMBUS_POUT_BOOLEANS_PER_PAGE;
+                       max_labels++;
+               }
+               if (info->func[page] & PMBUS_HAVE_FAN12) {
+                       if (page == 0) {
+                               max_sensors +=
+                                   ARRAY_SIZE(pmbus_fan_registers) *
+                                   PMBUS_MAX_SENSORS_PER_FAN;
+                               max_booleans +=
+                                   ARRAY_SIZE(pmbus_fan_registers) *
+                                   PMBUS_MAX_BOOLEANS_PER_FAN;
+                       } else {
+                               max_sensors += PMBUS_MAX_SENSORS_PER_FAN;
+                               max_booleans += PMBUS_MAX_BOOLEANS_PER_FAN;
+                       }
+               }
+               if (info->func[page] & PMBUS_HAVE_TEMP) {
+                       if (page == 0) {
+                               max_sensors +=
+                                   ARRAY_SIZE(pmbus_temp_registers) *
+                                   PMBUS_MAX_SENSORS_PER_TEMP;
+                               max_booleans +=
+                                   ARRAY_SIZE(pmbus_temp_registers) *
+                                   PMBUS_MAX_BOOLEANS_PER_TEMP;
+                       } else {
+                               max_sensors += PMBUS_MAX_SENSORS_PER_TEMP;
+                               max_booleans += PMBUS_MAX_BOOLEANS_PER_TEMP;
+                       }
+               }
+       }
+       data->max_sensors = max_sensors;
+       data->max_booleans = max_booleans;
+       data->max_labels = max_labels;
+       data->max_attributes = max_sensors + max_booleans + max_labels;
+}
+
+/*
+ * Search for attributes. Allocate sensors, booleans, and labels as needed.
+ */
+static void pmbus_find_attributes(struct i2c_client *client,
+                                 struct pmbus_data *data)
+{
+       const struct pmbus_driver_info *info = data->info;
+       int page, i0, i1, in_index;
+
+       /*
+        * Input voltage sensors
+        */
+       in_index = 1;
+       if (info->func[0] & PMBUS_HAVE_VIN) {
+               bool have_alarm = false;
+
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "in", in_index, "vin", 0);
+               pmbus_add_sensor(data, "in", "input", in_index,
+                                0, PMBUS_READ_VIN, PSC_VOLTAGE_IN, true);
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_VIN_UV_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "min", in_index,
+                                        0, PMBUS_VIN_UV_WARN_LIMIT,
+                                        PSC_VOLTAGE_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT) {
+                               pmbus_add_boolean_reg(data, "in", "min_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_VOLTAGE_UV_WARNING);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_VIN_UV_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "lcrit", in_index,
+                                        0, PMBUS_VIN_UV_FAULT_LIMIT,
+                                        PSC_VOLTAGE_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT) {
+                               pmbus_add_boolean_reg(data, "in", "lcrit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_VOLTAGE_UV_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_VIN_OV_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "max", in_index,
+                                        0, PMBUS_VIN_OV_WARN_LIMIT,
+                                        PSC_VOLTAGE_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT) {
+                               pmbus_add_boolean_reg(data, "in", "max_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_VOLTAGE_OV_WARNING);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_VIN_OV_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "crit", in_index,
+                                        0, PMBUS_VIN_OV_FAULT_LIMIT,
+                                        PSC_VOLTAGE_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT) {
+                               pmbus_add_boolean_reg(data, "in", "crit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_VOLTAGE_OV_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               /*
+                * Add generic alarm attribute only if there are no individual
+                * attributes.
+                */
+               if (!have_alarm)
+                       pmbus_add_boolean_reg(data, "in", "alarm",
+                                             in_index,
+                                             PB_STATUS_BASE,
+                                             PB_STATUS_VIN_UV);
+               in_index++;
+       }
+       if (info->func[0] & PMBUS_HAVE_VCAP) {
+               pmbus_add_label(data, "in", in_index, "vcap", 0);
+               pmbus_add_sensor(data, "in", "input", in_index, 0,
+                                PMBUS_READ_VCAP, PSC_VOLTAGE_IN, true);
+               in_index++;
+       }
+
+       /*
+        * Output voltage sensors
+        */
+       for (page = 0; page < info->pages; page++) {
+               bool have_alarm = false;
+
+               if (!(info->func[page] & PMBUS_HAVE_VOUT))
+                       continue;
+
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "in", in_index, "vout", page + 1);
+               pmbus_add_sensor(data, "in", "input", in_index, page,
+                                PMBUS_READ_VOUT, PSC_VOLTAGE_OUT, true);
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_VOUT_UV_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "min", in_index, page,
+                                        PMBUS_VOUT_UV_WARN_LIMIT,
+                                        PSC_VOLTAGE_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_VOUT) {
+                               pmbus_add_boolean_reg(data, "in", "min_alarm",
+                                                     in_index,
+                                                     PB_STATUS_VOUT_BASE +
+                                                     page,
+                                                     PB_VOLTAGE_UV_WARNING);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_VOUT_UV_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "lcrit", in_index, page,
+                                        PMBUS_VOUT_UV_FAULT_LIMIT,
+                                        PSC_VOLTAGE_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_VOUT) {
+                               pmbus_add_boolean_reg(data, "in", "lcrit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_VOUT_BASE +
+                                                     page,
+                                                     PB_VOLTAGE_UV_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_VOUT_OV_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "max", in_index, page,
+                                        PMBUS_VOUT_OV_WARN_LIMIT,
+                                        PSC_VOLTAGE_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_VOUT) {
+                               pmbus_add_boolean_reg(data, "in", "max_alarm",
+                                                     in_index,
+                                                     PB_STATUS_VOUT_BASE +
+                                                     page,
+                                                     PB_VOLTAGE_OV_WARNING);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_VOUT_OV_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "in", "crit", in_index, page,
+                                        PMBUS_VOUT_OV_FAULT_LIMIT,
+                                        PSC_VOLTAGE_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_VOUT) {
+                               pmbus_add_boolean_reg(data, "in", "crit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_VOUT_BASE +
+                                                     page,
+                                                     PB_VOLTAGE_OV_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               /*
+                * Add generic alarm attribute only if there are no individual
+                * attributes.
+                */
+               if (!have_alarm)
+                       pmbus_add_boolean_reg(data, "in", "alarm",
+                                             in_index,
+                                             PB_STATUS_BASE + page,
+                                             PB_STATUS_VOUT_OV);
+               in_index++;
+       }
+
+       /*
+        * Current sensors
+        */
+
+       /*
+        * Input current sensors
+        */
+       in_index = 1;
+       if (info->func[0] & PMBUS_HAVE_IIN) {
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "curr", in_index, "iin", 0);
+               pmbus_add_sensor(data, "curr", "input", in_index,
+                                0, PMBUS_READ_IIN, PSC_CURRENT_IN, true);
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_IIN_OC_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "curr", "max", in_index,
+                                        0, PMBUS_IIN_OC_WARN_LIMIT,
+                                        PSC_CURRENT_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT) {
+                               pmbus_add_boolean_reg(data, "curr", "max_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_IIN_OC_WARNING);
+                       }
+               }
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_IIN_OC_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "curr", "crit", in_index,
+                                        0, PMBUS_IIN_OC_FAULT_LIMIT,
+                                        PSC_CURRENT_IN, false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
+                               pmbus_add_boolean_reg(data, "curr",
+                                                     "crit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_IIN_OC_FAULT);
+               }
+               in_index++;
+       }
+
+       /*
+        * Output current sensors
+        */
+       for (page = 0; page < info->pages; page++) {
+               bool have_alarm = false;
+
+               if (!(info->func[page] & PMBUS_HAVE_IOUT))
+                       continue;
+
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "curr", in_index, "iout", page + 1);
+               pmbus_add_sensor(data, "curr", "input", in_index, page,
+                                PMBUS_READ_IOUT, PSC_CURRENT_OUT, true);
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_IOUT_OC_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "curr", "max", in_index, page,
+                                        PMBUS_IOUT_OC_WARN_LIMIT,
+                                        PSC_CURRENT_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_IOUT) {
+                               pmbus_add_boolean_reg(data, "curr", "max_alarm",
+                                                     in_index,
+                                                     PB_STATUS_IOUT_BASE +
+                                                     page, PB_IOUT_OC_WARNING);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_IOUT_UC_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "curr", "lcrit", in_index, page,
+                                        PMBUS_IOUT_UC_FAULT_LIMIT,
+                                        PSC_CURRENT_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_IOUT) {
+                               pmbus_add_boolean_reg(data, "curr",
+                                                     "lcrit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_IOUT_BASE +
+                                                     page, PB_IOUT_UC_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_IOUT_OC_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "curr", "crit", in_index, page,
+                                        PMBUS_IOUT_OC_FAULT_LIMIT,
+                                        PSC_CURRENT_OUT, false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_IOUT) {
+                               pmbus_add_boolean_reg(data, "curr",
+                                                     "crit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_IOUT_BASE +
+                                                     page, PB_IOUT_OC_FAULT);
+                               have_alarm = true;
+                       }
+               }
+               /*
+                * Add generic alarm attribute only if there are no individual
+                * attributes.
+                */
+               if (!have_alarm)
+                       pmbus_add_boolean_reg(data, "curr", "alarm",
+                                             in_index,
+                                             PB_STATUS_BASE + page,
+                                             PB_STATUS_IOUT_OC);
+               in_index++;
+       }
+
+       /*
+        * Power sensors
+        */
+       /*
+        * Input Power sensors
+        */
+       in_index = 1;
+       if (info->func[0] & PMBUS_HAVE_PIN) {
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "power", in_index, "pin", 0);
+               pmbus_add_sensor(data, "power", "input", in_index,
+                                0, PMBUS_READ_PIN, PSC_POWER, true);
+               if (pmbus_check_word_register(client, 0,
+                                             PMBUS_PIN_OP_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "power", "max", in_index,
+                                        0, PMBUS_PIN_OP_WARN_LIMIT, PSC_POWER,
+                                        false);
+                       if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
+                               pmbus_add_boolean_reg(data, "power",
+                                                     "alarm",
+                                                     in_index,
+                                                     PB_STATUS_INPUT_BASE,
+                                                     PB_PIN_OP_WARNING);
+               }
+               in_index++;
+       }
+
+       /*
+        * Output Power sensors
+        */
+       for (page = 0; page < info->pages; page++) {
+               bool need_alarm = false;
+
+               if (!(info->func[page] & PMBUS_HAVE_POUT))
+                       continue;
+
+               i0 = data->num_sensors;
+               pmbus_add_label(data, "power", in_index, "pout", page + 1);
+               pmbus_add_sensor(data, "power", "input", in_index, page,
+                                PMBUS_READ_POUT, PSC_POWER, true);
+               /*
+                * Per hwmon sysfs API, power_cap is to be used to limit output
+                * power.
+                * We have two registers related to maximum output power,
+                * PMBUS_POUT_MAX and PMBUS_POUT_OP_WARN_LIMIT.
+                * PMBUS_POUT_MAX matches the powerX_cap attribute definition.
+                * There is no attribute in the API to match
+                * PMBUS_POUT_OP_WARN_LIMIT. We use powerX_max for now.
+                */
+               if (pmbus_check_word_register(client, page, PMBUS_POUT_MAX)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "power", "cap", in_index, page,
+                                        PMBUS_POUT_MAX, PSC_POWER, false);
+                       need_alarm = true;
+               }
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_POUT_OP_WARN_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "power", "max", in_index, page,
+                                        PMBUS_POUT_OP_WARN_LIMIT, PSC_POWER,
+                                        false);
+                       need_alarm = true;
+               }
+               if (need_alarm && (info->func[page] & PMBUS_HAVE_STATUS_IOUT))
+                       pmbus_add_boolean_reg(data, "power", "alarm",
+                                             in_index,
+                                             PB_STATUS_IOUT_BASE + page,
+                                             PB_POUT_OP_WARNING
+                                             | PB_POWER_LIMITING);
+
+               if (pmbus_check_word_register(client, page,
+                                             PMBUS_POUT_OP_FAULT_LIMIT)) {
+                       i1 = data->num_sensors;
+                       pmbus_add_sensor(data, "power", "crit", in_index, page,
+                                        PMBUS_POUT_OP_FAULT_LIMIT, PSC_POWER,
+                                        false);
+                       if (info->func[page] & PMBUS_HAVE_STATUS_IOUT)
+                               pmbus_add_boolean_reg(data, "power",
+                                                     "crit_alarm",
+                                                     in_index,
+                                                     PB_STATUS_IOUT_BASE
+                                                     + page,
+                                                     PB_POUT_OP_FAULT);
+               }
+               in_index++;
+       }
+
+       /*
+        * Temperature sensors
+        */
+       in_index = 1;
+       for (page = 0; page < info->pages; page++) {
+               int t, temps;
+
+               if (!(info->func[page] & PMBUS_HAVE_TEMP))
+                       continue;
+
+               temps = page ? 1 : ARRAY_SIZE(pmbus_temp_registers);
+               for (t = 0; t < temps; t++) {
+                       bool have_alarm = false;
+
+                       if (!pmbus_check_word_register
+                           (client, page, pmbus_temp_registers[t]))
+                               break;
+
+                       i0 = data->num_sensors;
+                       pmbus_add_sensor(data, "temp", "input", in_index, page,
+                                        pmbus_temp_registers[t],
+                                        PSC_TEMPERATURE, true);
+
+                       /*
+                        * PMBus provides only one status register for TEMP1-3.
+                        * Thus, we can not use the status register to determine
+                        * which of the three sensors actually caused an alarm.
+                        * Always compare current temperature against the limit
+                        * registers to determine alarm conditions for a
+                        * specific sensor.
+                        */
+                       if (pmbus_check_word_register
+                           (client, page, PMBUS_UT_WARN_LIMIT)) {
+                               i1 = data->num_sensors;
+                               pmbus_add_sensor(data, "temp", "min", in_index,
+                                                page, PMBUS_UT_WARN_LIMIT,
+                                                PSC_TEMPERATURE, false);
+                               if (info->func[page] & PMBUS_HAVE_STATUS_TEMP) {
+                                       pmbus_add_boolean_cmp(data, "temp",
+                                               "min_alarm", in_index, i1, i0,
+                                               PB_STATUS_TEMP_BASE + page,
+                                               PB_TEMP_UT_WARNING);
+                                       have_alarm = true;
+                               }
+                       }
+                       if (pmbus_check_word_register(client, page,
+                                                     PMBUS_UT_FAULT_LIMIT)) {
+                               i1 = data->num_sensors;
+                               pmbus_add_sensor(data, "temp", "lcrit",
+                                                in_index, page,
+                                                PMBUS_UT_FAULT_LIMIT,
+                                                PSC_TEMPERATURE, false);
+                               if (info->func[page] & PMBUS_HAVE_STATUS_TEMP) {
+                                       pmbus_add_boolean_cmp(data, "temp",
+                                               "lcrit_alarm", in_index, i1, i0,
+                                               PB_STATUS_TEMP_BASE + page,
+                                               PB_TEMP_UT_FAULT);
+                                       have_alarm = true;
+                               }
+                       }
+                       if (pmbus_check_word_register
+                           (client, page, PMBUS_OT_WARN_LIMIT)) {
+                               i1 = data->num_sensors;
+                               pmbus_add_sensor(data, "temp", "max", in_index,
+                                                page, PMBUS_OT_WARN_LIMIT,
+                                                PSC_TEMPERATURE, false);
+                               if (info->func[page] & PMBUS_HAVE_STATUS_TEMP) {
+                                       pmbus_add_boolean_cmp(data, "temp",
+                                               "max_alarm", in_index, i0, i1,
+                                               PB_STATUS_TEMP_BASE + page,
+                                               PB_TEMP_OT_WARNING);
+                                       have_alarm = true;
+                               }
+                       }
+                       if (pmbus_check_word_register(client, page,
+                                                     PMBUS_OT_FAULT_LIMIT)) {
+                               i1 = data->num_sensors;
+                               pmbus_add_sensor(data, "temp", "crit", in_index,
+                                                page, PMBUS_OT_FAULT_LIMIT,
+                                                PSC_TEMPERATURE, false);
+                               if (info->func[page] & PMBUS_HAVE_STATUS_TEMP) {
+                                       pmbus_add_boolean_cmp(data, "temp",
+                                               "crit_alarm", in_index, i0, i1,
+                                               PB_STATUS_TEMP_BASE + page,
+                                               PB_TEMP_OT_FAULT);
+                                       have_alarm = true;
+                               }
+                       }
+                       /*
+                        * Last resort - we were not able to create any alarm
+                        * registers. Report alarm for all sensors using the
+                        * status register temperature alarm bit.
+                        */
+                       if (!have_alarm)
+                               pmbus_add_boolean_reg(data, "temp", "alarm",
+                                                     in_index,
+                                                     PB_STATUS_BASE + page,
+                                                     PB_STATUS_TEMPERATURE);
+                       in_index++;
+               }
+       }
+
+       /*
+        * Fans
+        */
+       in_index = 1;
+       for (page = 0; page < info->pages; page++) {
+               int fans, f;
+
+               if (!(info->func[page] & PMBUS_HAVE_FAN12))
+                       continue;
+
+               fans = page ? 1 : ARRAY_SIZE(pmbus_fan_registers);
+               for (f = 0; f < fans; f++) {
+                       int regval;
+
+                       if (!pmbus_check_word_register(client, page,
+                                                      pmbus_fan_registers[f])
+                           || !pmbus_check_byte_register(client, page,
+                                               pmbus_fan_config_registers[f]))
+                               break;
+
+                       /*
+                        * Skip fan if not installed.
+                        * Each fan configuration register covers multiple fans,
+                        * so we have to do some magic.
+                        */
+                       regval = pmbus_read_byte_data(client, page,
+                               pmbus_fan_config_registers[f]);
+                       if (regval < 0 ||
+                           (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
+                               continue;
+
+                       i0 = data->num_sensors;
+                       pmbus_add_sensor(data, "fan", "input", in_index, page,
+                                        pmbus_fan_registers[f], PSC_FAN, true);
+
+                       /*
+                        * Each fan status register covers multiple fans,
+                        * so we have to do some magic.
+                        */
+                       if (pmbus_check_byte_register
+                           (client, page, pmbus_fan_status_registers[f])) {
+                               int base;
+
+                               if (f > 1)      /* fan 3, 4 */
+                                       base = PB_STATUS_FAN34_BASE;
+                               else
+                                       base = PB_STATUS_FAN_BASE + page;
+                               pmbus_add_boolean_reg(data, "fan", "alarm",
+                                       in_index, base,
+                                       PB_FAN_FAN1_WARNING >> (f & 1));
+                               pmbus_add_boolean_reg(data, "fan", "fault",
+                                       in_index, base,
+                                       PB_FAN_FAN1_FAULT >> (f & 1));
+                       }
+                       in_index++;
+               }
+       }
+}
+
+/*
+ * Identify chip parameters.
+ * This function is called for all chips.
+ */
+static int pmbus_identify_common(struct i2c_client *client,
+                                struct pmbus_data *data)
+{
+       int vout_mode, exponent;
+
+       vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
+       if (vout_mode >= 0) {
+               /*
+                * Not all chips support the VOUT_MODE command,
+                * so a failure to read it is not an error.
+                */
+               switch (vout_mode >> 5) {
+               case 0: /* linear mode      */
+                       if (data->info->direct[PSC_VOLTAGE_OUT])
+                               return -ENODEV;
+
+                       exponent = vout_mode & 0x1f;
+                       /* and sign-extend it */
+                       if (exponent & 0x10)
+                               exponent |= ~0x1f;
+                       data->exponent = exponent;
+                       break;
+               case 2: /* direct mode      */
+                       if (!data->info->direct[PSC_VOLTAGE_OUT])
+                               return -ENODEV;
+                       break;
+               default:
+                       return -ENODEV;
+               }
+       }
+
+       /* Determine maximum number of sensors, booleans, and labels */
+       pmbus_find_max_attr(client, data);
+       pmbus_clear_fault_page(client, 0);
+       return 0;
+}
+
+int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
+                  struct pmbus_driver_info *info)
+{
+       const struct pmbus_platform_data *pdata = client->dev.platform_data;
+       struct pmbus_data *data;
+       int ret;
+
+       if (!info) {
+               dev_err(&client->dev, "Missing chip information");
+               return -ENODEV;
+       }
+
+       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
+                                    | I2C_FUNC_SMBUS_BYTE_DATA
+                                    | I2C_FUNC_SMBUS_WORD_DATA))
+               return -ENODEV;
+
+       data = kzalloc(sizeof(*data), GFP_KERNEL);
+       if (!data) {
+               dev_err(&client->dev, "No memory to allocate driver data\n");
+               return -ENOMEM;
+       }
+
+       i2c_set_clientdata(client, data);
+       mutex_init(&data->update_lock);
+
+       /*
+        * Bail out if status register or PMBus revision register
+        * does not exist.
+        */
+       if (i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE) < 0
+           || i2c_smbus_read_byte_data(client, PMBUS_REVISION) < 0) {
+               dev_err(&client->dev,
+                       "Status or revision register not found\n");
+               ret = -ENODEV;
+               goto out_data;
+       }
+
+       if (pdata)
+               data->flags = pdata->flags;
+       data->info = info;
+
+       pmbus_clear_faults(client);
+
+       if (info->identify) {
+               ret = (*info->identify)(client, info);
+               if (ret < 0) {
+                       dev_err(&client->dev, "Chip identification failed\n");
+                       goto out_data;
+               }
+       }
+
+       if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
+               dev_err(&client->dev, "Bad number of PMBus pages: %d\n",
+                       info->pages);
+               ret = -EINVAL;
+               goto out_data;
+       }
+       /*
+        * Bail out if more than one page was configured, but we can not
+        * select the highest page. This is an indication that the wrong
+        * chip type was selected. Better bail out now than keep
+        * returning errors later on.
+        */
+       if (info->pages > 1 && pmbus_set_page(client, info->pages - 1) < 0) {
+               dev_err(&client->dev, "Failed to select page %d\n",
+                       info->pages - 1);
+               ret = -EINVAL;
+               goto out_data;
+       }
+
+       ret = pmbus_identify_common(client, data);
+       if (ret < 0) {
+               dev_err(&client->dev, "Failed to identify chip capabilities\n");
+               goto out_data;
+       }
+
+       ret = -ENOMEM;
+       data->sensors = kzalloc(sizeof(struct pmbus_sensor) * data->max_sensors,
+                               GFP_KERNEL);
+       if (!data->sensors) {
+               dev_err(&client->dev, "No memory to allocate sensor data\n");
+               goto out_data;
+       }
+
+       data->booleans = kzalloc(sizeof(struct pmbus_boolean)
+                                * data->max_booleans, GFP_KERNEL);
+       if (!data->booleans) {
+               dev_err(&client->dev, "No memory to allocate boolean data\n");
+               goto out_sensors;
+       }
+
+       data->labels = kzalloc(sizeof(struct pmbus_label) * data->max_labels,
+                              GFP_KERNEL);
+       if (!data->labels) {
+               dev_err(&client->dev, "No memory to allocate label data\n");
+               goto out_booleans;
+       }
+
+       data->attributes = kzalloc(sizeof(struct attribute *)
+                                  * data->max_attributes, GFP_KERNEL);
+       if (!data->attributes) {
+               dev_err(&client->dev, "No memory to allocate attribute data\n");
+               goto out_labels;
+       }
+
+       pmbus_find_attributes(client, data);
+
+       /*
+        * If there are no attributes, something is wrong.
+        * Bail out instead of trying to register nothing.
+        */
+       if (!data->num_attributes) {
+               dev_err(&client->dev, "No attributes found\n");
+               ret = -ENODEV;
+               goto out_attributes;
+       }
+
+       /* Register sysfs hooks */
+       data->group.attrs = data->attributes;
+       ret = sysfs_create_group(&client->dev.kobj, &data->group);
+       if (ret) {
+               dev_err(&client->dev, "Failed to create sysfs entries\n");
+               goto out_attributes;
+       }
+       data->hwmon_dev = hwmon_device_register(&client->dev);
+       if (IS_ERR(data->hwmon_dev)) {
+               ret = PTR_ERR(data->hwmon_dev);
+               dev_err(&client->dev, "Failed to register hwmon device\n");
+               goto out_hwmon_device_register;
+       }
+       return 0;
+
+out_hwmon_device_register:
+       sysfs_remove_group(&client->dev.kobj, &data->group);
+out_attributes:
+       kfree(data->attributes);
+out_labels:
+       kfree(data->labels);
+out_booleans:
+       kfree(data->booleans);
+out_sensors:
+       kfree(data->sensors);
+out_data:
+       kfree(data);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(pmbus_do_probe);
+
+int pmbus_do_remove(struct i2c_client *client)
+{
+       struct pmbus_data *data = i2c_get_clientdata(client);
+       hwmon_device_unregister(data->hwmon_dev);
+       sysfs_remove_group(&client->dev.kobj, &data->group);
+       kfree(data->attributes);
+       kfree(data->labels);
+       kfree(data->booleans);
+       kfree(data->sensors);
+       kfree(data);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(pmbus_do_remove);
+
+MODULE_AUTHOR("Guenter Roeck");
+MODULE_DESCRIPTION("PMBus core driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/i2c/pmbus.h b/include/linux/i2c/pmbus.h
new file mode 100644 (file)
index 0000000..69280db
--- /dev/null
@@ -0,0 +1,45 @@
+/*
+ * Hardware monitoring driver for PMBus devices
+ *
+ * Copyright (c) 2010, 2011 Ericsson AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _PMBUS_H_
+#define _PMBUS_H_
+
+/* flags */
+
+/*
+ * PMBUS_SKIP_STATUS_CHECK
+ *
+ * During register detection, skip checking the status register for
+ * communication or command errors.
+ *
+ * Some PMBus chips respond with valid data when trying to read an unsupported
+ * register. For such chips, checking the status register is mandatory when
+ * trying to determine if a chip register exists or not.
+ * Other PMBus chips don't support the STATUS_CML register, or report
+ * communication errors for no explicable reason. For such chips, checking
+ * the status register must be disabled.
+ */
+#define PMBUS_SKIP_STATUS_CHECK        (1 << 0)
+
+struct pmbus_platform_data {
+       u32 flags;              /* Device specific flags */
+};
+
+#endif /* _PMBUS_H_ */