Commit 01a52397 authored by David Brownell's avatar David Brownell Committed by Mark M. Hoffman
Browse files

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: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Acked-by: default avatarJean Delvare <khali@linux-fr.org>
Acked-by: default avatarLaurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: default avatarMark M. Hoffman <mhoffman@lightlink.com>
parent 321c4138

drivers/hwmon/Kconfig

+13 −7
Original line number Diff line number Diff line
@@ -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.

drivers/hwmon/lm75.c

+51 −39
Original line number Diff line number Diff line
@@ -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
@@ -52,7 +57,7 @@ struct lm75_data { 
	struct i2c_client	client;

	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;
@@ -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);
@@ -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);

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