From: bgardner@wabtec.com Date: Tue, 7 Jun 2005 13:55:38 +0000 (-0500) Subject: [PATCH] I2C: add new pca9539 driver X-Git-Tag: MMI-PSA29.97-13-9~56759^2~160^2~5 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=69dd204b6b45987dbf9ce7058cd238d355865281;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git [PATCH] I2C: add new pca9539 driver This is an i2c driver for the Philips PCA9539 (16 bit I/O port). It uses the new i2c-sysfs interfaces. The patch includes documentation. It depends on the patch that renames "i2c-sysfs.h" to "hwmon-sysfs.h" Signed-off-by: Ben Gardner Signed-off-by: Greg Kroah-Hartman --- diff --git a/Documentation/i2c/chips/pca9539 b/Documentation/i2c/chips/pca9539 new file mode 100644 index 000000000000..c4fce6a13537 --- /dev/null +++ b/Documentation/i2c/chips/pca9539 @@ -0,0 +1,47 @@ +Kernel driver pca9539 +===================== + +Supported chips: + * Philips PCA9539 + Prefix: 'pca9539' + Addresses scanned: 0x74 - 0x77 + Datasheet: + http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf + +Author: Ben Gardner + + +Description +----------- + +The Philips PCA9539 is a 16 bit low power I/O device. +All 16 lines can be individually configured as an input or output. +The input sense can also be inverted. +The 16 lines are split between two bytes. + + +Sysfs entries +------------- + +Each is a byte that maps to the 8 I/O bits. +A '0' suffix is for bits 0-7, while '1' is for bits 8-15. + +input[01] - read the current value +output[01] - sets the output value +direction[01] - direction of each bit: 1=input, 0=output +invert[01] - toggle the input bit sense + +input reads the actual state of the line and is always available. +The direction defaults to input for all channels. + + +General Remarks +--------------- + +Note that each output, direction, and invert entry controls 8 lines. +You should use the read, modify, write sequence. +For example. to set output bit 0 of 1. + val=$(cat output0) + val=$(( $val | 1 )) + echo $val > output0 + diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig index 88437d046518..33de80afd6c6 100644 --- a/drivers/i2c/chips/Kconfig +++ b/drivers/i2c/chips/Kconfig @@ -440,6 +440,16 @@ config SENSORS_PCF8574 This driver can also be built as a module. If so, the module will be called pcf8574. +config SENSORS_PCA9539 + tristate "Philips PCA9539 16-bit I/O port" + depends on I2C && EXPERIMENTAL + help + If you say yes here you get support for the Philips PCA9539 + 16-bit I/O port. + + This driver can also be built as a module. If so, the module + will be called pca9539. + config SENSORS_PCF8591 tristate "Philips PCF8591" depends on I2C && EXPERIMENTAL diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile index 8eed2381da68..6bebdc104166 100644 --- a/drivers/i2c/chips/Makefile +++ b/drivers/i2c/chips/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_SENSORS_MAX1619) += max1619.o obj-$(CONFIG_SENSORS_MAX6875) += max6875.o obj-$(CONFIG_SENSORS_M41T00) += m41t00.o obj-$(CONFIG_SENSORS_PC87360) += pc87360.o +obj-$(CONFIG_SENSORS_PCA9539) += pca9539.o obj-$(CONFIG_SENSORS_PCF8574) += pcf8574.o obj-$(CONFIG_SENSORS_PCF8591) += pcf8591.o obj-$(CONFIG_SENSORS_RTC8564) += rtc8564.o diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c new file mode 100644 index 000000000000..9f3ad45daae2 --- /dev/null +++ b/drivers/i2c/chips/pca9539.c @@ -0,0 +1,192 @@ +/* + pca9539.c - 16-bit I/O port with interrupt and reset + + Copyright (C) 2005 Ben Gardner + + 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; version 2 of the License. +*/ + +#include +#include +#include +#include +#include +#include + +/* Addresses to scan */ +static unsigned short normal_i2c[] = {0x74, 0x75, 0x76, 0x77, I2C_CLIENT_END}; +static unsigned int normal_isa[] = {I2C_CLIENT_ISA_END}; + +/* Insmod parameters */ +SENSORS_INSMOD_1(pca9539); + +enum pca9539_cmd +{ + PCA9539_INPUT_0 = 0, + PCA9539_INPUT_1 = 1, + PCA9539_OUTPUT_0 = 2, + PCA9539_OUTPUT_1 = 3, + PCA9539_INVERT_0 = 4, + PCA9539_INVERT_1 = 5, + PCA9539_DIRECTION_0 = 6, + PCA9539_DIRECTION_1 = 7, +}; + +static int pca9539_attach_adapter(struct i2c_adapter *adapter); +static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind); +static int pca9539_detach_client(struct i2c_client *client); + +/* This is the driver that will be inserted */ +static struct i2c_driver pca9539_driver = { + .owner = THIS_MODULE, + .name = "pca9539", + .flags = I2C_DF_NOTIFY, + .attach_adapter = pca9539_attach_adapter, + .detach_client = pca9539_detach_client, +}; + +struct pca9539_data { + struct i2c_client client; +}; + +/* following are the sysfs callback functions */ +static ssize_t pca9539_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct sensor_device_attribute *psa = to_sensor_dev_attr(attr); + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%d\n", i2c_smbus_read_byte_data(client, + psa->index)); +} + +static ssize_t pca9539_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct sensor_device_attribute *psa = to_sensor_dev_attr(attr); + struct i2c_client *client = to_i2c_client(dev); + unsigned long val = simple_strtoul(buf, NULL, 0); + if (val > 0xff) + return -EINVAL; + i2c_smbus_write_byte_data(client, psa->index, val); + return count; +} + +/* Define the device attributes */ + +#define PCA9539_ENTRY_RO(name, cmd_idx) \ + static SENSOR_DEVICE_ATTR(name, S_IRUGO, pca9539_show, NULL, cmd_idx) + +#define PCA9539_ENTRY_RW(name, cmd_idx) \ + static SENSOR_DEVICE_ATTR(name, S_IRUGO | S_IWUSR, pca9539_show, \ + pca9539_store, cmd_idx) + +PCA9539_ENTRY_RO(input0, PCA9539_INPUT_0); +PCA9539_ENTRY_RO(input1, PCA9539_INPUT_1); +PCA9539_ENTRY_RW(output0, PCA9539_OUTPUT_0); +PCA9539_ENTRY_RW(output1, PCA9539_OUTPUT_1); +PCA9539_ENTRY_RW(invert0, PCA9539_INVERT_0); +PCA9539_ENTRY_RW(invert1, PCA9539_INVERT_1); +PCA9539_ENTRY_RW(direction0, PCA9539_DIRECTION_0); +PCA9539_ENTRY_RW(direction1, PCA9539_DIRECTION_1); + +static struct attribute *pca9539_attributes[] = { + &sensor_dev_attr_input0.dev_attr.attr, + &sensor_dev_attr_input1.dev_attr.attr, + &sensor_dev_attr_output0.dev_attr.attr, + &sensor_dev_attr_output1.dev_attr.attr, + &sensor_dev_attr_invert0.dev_attr.attr, + &sensor_dev_attr_invert1.dev_attr.attr, + &sensor_dev_attr_direction0.dev_attr.attr, + &sensor_dev_attr_direction1.dev_attr.attr, + NULL +}; + +static struct attribute_group pca9539_defattr_group = { + .attrs = pca9539_attributes, +}; + +static int pca9539_attach_adapter(struct i2c_adapter *adapter) +{ + return i2c_detect(adapter, &addr_data, pca9539_detect); +} + +/* This function is called by i2c_detect */ +static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind) +{ + struct i2c_client *new_client; + struct pca9539_data *data; + int err = 0; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + goto exit; + + /* OK. For now, we presume we have a valid client. We now create the + client structure, even though we cannot fill it completely yet. */ + if (!(data = kmalloc(sizeof(struct pca9539_data), GFP_KERNEL))) { + err = -ENOMEM; + goto exit; + } + memset(data, 0, sizeof(struct pca9539_data)); + + new_client = &data->client; + i2c_set_clientdata(new_client, data); + new_client->addr = address; + new_client->adapter = adapter; + new_client->driver = &pca9539_driver; + new_client->flags = 0; + + /* Detection: the pca9539 only has 8 registers (0-7). + A read of 7 should succeed, but a read of 8 should fail. */ + if ((i2c_smbus_read_byte_data(new_client, 7) < 0) || + (i2c_smbus_read_byte_data(new_client, 8) >= 0)) + goto exit_kfree; + + strlcpy(new_client->name, "pca9539", I2C_NAME_SIZE); + + /* Tell the I2C layer a new client has arrived */ + if ((err = i2c_attach_client(new_client))) + goto exit_kfree; + + /* Register sysfs hooks (don't care about failure) */ + sysfs_create_group(&new_client->dev.kobj, &pca9539_defattr_group); + + return 0; + +exit_kfree: + kfree(data); +exit: + return err; +} + +static int pca9539_detach_client(struct i2c_client *client) +{ + int err; + + if ((err = i2c_detach_client(client))) { + dev_err(&client->dev, "Client deregistration failed.\n"); + return err; + } + + kfree(i2c_get_clientdata(client)); + return 0; +} + +static int __init pca9539_init(void) +{ + return i2c_add_driver(&pca9539_driver); +} + +static void __exit pca9539_exit(void) +{ + i2c_del_driver(&pca9539_driver); +} + +MODULE_AUTHOR("Ben Gardner "); +MODULE_DESCRIPTION("PCA9539 driver"); +MODULE_LICENSE("GPL"); + +module_init(pca9539_init); +module_exit(pca9539_exit); +