hwmon: (lm75) cleanup/reorg

Minor cleanup and reorg of the lm75 code.

 - Kconfig provides a larger list of lm75-compatible chips

 - A top comment now says what the driver does (!) ... as in, just
   what sort of sensor is this??

 - Section comments now delineate the various sections of the driver:
   hwmon attributes, driver binding, register access, module glue.
   One driver binding function moved out of the attribute section,
   as did the driver struct itself.

 - Minor tweaks to legacy probe logic:  correct a comment, and
   remove a pointless variable.

 - Whitespace, linelength, and comment fixes.

This patch should include no functional changes.  It's preparation
for adding new-style (driver model) I2C driver binding.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 00ff53348491be4f12b3174187aacbf8cb9291b7..86289c283dc8d0784f4e0789e1bee73ec8627b92 100644 (file)
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -394,13 +394,19 @@ config SENSORS_LM75
        tristate "National Semiconductor LM75 and compatibles"
        depends on I2C
        help
-         If you say yes here you get support for National Semiconductor LM75
-         sensor chips and clones: Dallas Semiconductor DS75 and DS1775 (in
-         9-bit precision mode), and TelCom (now Microchip) TCN75.
-
-         The DS75 and DS1775 in 10- to 12-bit precision modes will require
-         a force module parameter. The driver will not handle the extra
-         precision anyhow.
+         If you say yes here you get support for one common type of
+         temperature sensor chip, with models including:
+
+               - Dallas Semiconductor DS75 and DS1775
+               - Maxim MAX6625 and MAX6626
+               - Microchip MCP980x
+               - National Semiconductor LM75
+               - NXP's LM75A
+               - ST Microelectronics STDS75
+               - TelCom (now Microchip) TCN75
+               - Texas Instruments TMP100, TMP101, TMP75, TMP175, TMP275
+
+         Most of these chips will require a "force" module parameter.
 
          This driver can also be built as a module.  If so, the module
          will be called lm75.

diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index de698dc73020ccdf7edf88d8697fa1740c49c67b..25ed265841004c0596d34484920aa11e5fd13b5b 100644 (file)
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -30,14 +30,19 @@
 #include "lm75.h"
 
 
-/* Addresses to scan */
+/*
+ * This driver handles the LM75 and compatible digital temperature sensors.
+ * Compatibles include at least the DS75, DS1775, MCP980x, STDS75, TCN75,
+ * TMP100, TMP101, TMP75, TMP175, and TMP275.
+ */
+
+/* Addresses scanned by legacy style driver binding */
 static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
                                        0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
 
-/* Insmod parameters */
+/* Insmod parameters (only for legacy style driver binding) */
 I2C_CLIENT_INSMOD_1(lm75);
 
-/* Many LM75 constants specified below */
 
 /* The LM75 registers */
 #define LM75_REG_CONF          0x01
@@ -50,9 +55,9 @@ static const u8 LM75_REG_TEMP[3] = {
 /* Each client has this additional data */
 struct lm75_data {
        struct i2c_client       client;
-       struct device *hwmon_dev;
+       struct device           *hwmon_dev;
        struct mutex            update_lock;
-       char                    valid;          /* !=0 if following fields are valid */
+       char                    valid;          /* !=0 if registers are valid */
        unsigned long           last_updated;   /* In jiffies */
        u16                     temp[3];        /* Register values,
                                                   0 = input
@@ -60,23 +65,15 @@ struct lm75_data {
                                                   2 = hyst */
 };
 
-static int lm75_attach_adapter(struct i2c_adapter *adapter);
-static int lm75_detect(struct i2c_adapter *adapter, int address, int kind);
 static void lm75_init_client(struct i2c_client *client);
-static int lm75_detach_client(struct i2c_client *client);
 static int lm75_read_value(struct i2c_client *client, u8 reg);
 static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
 static struct lm75_data *lm75_update_device(struct device *dev);
 
 
-/* This is the driver that will be inserted */
-static struct i2c_driver lm75_driver = {
-       .driver = {
-               .name   = "lm75",
-       },
-       .attach_adapter = lm75_attach_adapter,
-       .detach_client  = lm75_detach_client,
-};
+/*-----------------------------------------------------------------------*/
+
+/* sysfs attributes for hwmon */
 
 static ssize_t show_temp(struct device *dev, struct device_attribute *da,
                         char *buf)
@@ -109,13 +106,6 @@ static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
                        show_temp, set_temp, 2);
 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 
-static int lm75_attach_adapter(struct i2c_adapter *adapter)
-{
-       if (!(adapter->class & I2C_CLASS_HWMON))
-               return 0;
-       return i2c_probe(adapter, &addr_data, lm75_detect);
-}
-
 static struct attribute *lm75_attributes[] = {
        &sensor_dev_attr_temp1_input.dev_attr.attr,
        &sensor_dev_attr_temp1_max.dev_attr.attr,
@@ -128,6 +118,12 @@ static const struct attribute_group lm75_group = {
        .attrs = lm75_attributes,
 };
 
+/*-----------------------------------------------------------------------*/
+
+/* "Legacy" I2C driver binding */
+
+static struct i2c_driver lm75_driver;
+
 /* This function is called by i2c_probe */
 static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
 {
@@ -135,15 +131,14 @@ static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
        struct i2c_client *new_client;
        struct lm75_data *data;
        int err = 0;
-       const char *name = "";
 
        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
                                     I2C_FUNC_SMBUS_WORD_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.
-          But it allows us to access lm75_{read,write}_value. */
+       /* OK. For now, we presume we have a valid address. We create the
+          client structure, even though there may be no sensor present.
+          But it allows us to use i2c_smbus_read_*_data() calls. */
        if (!(data = kzalloc(sizeof(struct lm75_data), GFP_KERNEL))) {
                err = -ENOMEM;
                goto exit;
@@ -174,17 +169,17 @@ static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
                 || i2c_smbus_read_word_data(new_client, 5) != hyst
                 || i2c_smbus_read_word_data(new_client, 6) != hyst
                 || i2c_smbus_read_word_data(new_client, 7) != hyst)
-                       goto exit_free;
+                       goto exit_free;
                os = i2c_smbus_read_word_data(new_client, 3);
                if (i2c_smbus_read_word_data(new_client, 4) != os
                 || i2c_smbus_read_word_data(new_client, 5) != os
                 || i2c_smbus_read_word_data(new_client, 6) != os
                 || i2c_smbus_read_word_data(new_client, 7) != os)
-                       goto exit_free;
+                       goto exit_free;
 
                /* Unused bits */
                if (conf & 0xe0)
-                       goto exit_free;
+                       goto exit_free;
 
                /* Addresses cycling */
                for (i = 8; i < 0xff; i += 8)
@@ -194,16 +189,10 @@ static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
                                goto exit_free;
        }
 
-       /* Determine the chip type - only one kind supported! */
-       if (kind <= 0)
-               kind = lm75;
-
-       if (kind == lm75) {
-               name = "lm75";
-       }
+       /* NOTE: we treat "force=..." and "force_lm75=..." the same. */
+       strlcpy(new_client->name, "lm75", I2C_NAME_SIZE);
 
        /* Fill in the remaining client fields and put it into the global list */
-       strlcpy(new_client->name, name, I2C_NAME_SIZE);
        data->valid = 0;
        mutex_init(&data->update_lock);
 
@@ -213,7 +202,7 @@ static int lm75_detect(struct i2c_adapter *adapter, int address, int kind)
 
        /* Initialize the LM75 chip */
        lm75_init_client(new_client);
-       
+
        /* Register sysfs hooks */
        if ((err = sysfs_create_group(&new_client->dev.kobj, &lm75_group)))
                goto exit_detach;
@@ -236,6 +225,13 @@ exit:
        return err;
 }
 
+static int lm75_attach_adapter(struct i2c_adapter *adapter)
+{
+       if (!(adapter->class & I2C_CLASS_HWMON))
+               return 0;
+       return i2c_probe(adapter, &addr_data, lm75_detect);
+}
+
 static int lm75_detach_client(struct i2c_client *client)
 {
        struct lm75_data *data = i2c_get_clientdata(client);
@@ -246,6 +242,18 @@ static int lm75_detach_client(struct i2c_client *client)
        return 0;
 }
 
+static struct i2c_driver lm75_driver = {
+       .driver = {
+               .name   = "lm75",
+       },
+       .attach_adapter = lm75_attach_adapter,
+       .detach_client  = lm75_detach_client,
+};
+
+/*-----------------------------------------------------------------------*/
+
+/* register access */
+
 /* All registers are word-sized, except for the configuration register.
    LM75 uses a high-byte first convention, which is exactly opposite to
    the SMBus standard. */
@@ -309,6 +317,10 @@ static struct lm75_data *lm75_update_device(struct device *dev)
        return data;
 }
 
+/*-----------------------------------------------------------------------*/
+
+/* module glue */
+
 static int __init sensors_lm75_init(void)
 {
        return i2c_add_driver(&lm75_driver);