Commit b2469f42 authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
Browse files

hwmon: (w83795) Refactor bank selection 



Move the bank selection code to a separate function, to avoid
duplicating it in read and write functions. Improve error reporting
on register access error.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 093d1a47

drivers/hwmon/w83795.c

+50 −43
Original line number Diff line number Diff line
@@ -360,60 +360,67 @@ struct w83795_data { 


/*

 * Hardware access

 * We assume that nobdody can change the bank outside the driver.

 */



/* Ignore the possibility that somebody change bank outside the driver

 * Must be called with data->update_lock held, except during initialization */

static u8 w83795_read(struct i2c_client *client, u16 reg)

/* Must be called with data->update_lock held, except during initialization */

static int w83795_set_bank(struct i2c_client *client, u8 bank)

{

	struct w83795_data *data = i2c_get_clientdata(client);

	u8 res = 0xff;

	u8 new_bank = reg >> 8;



	new_bank |= data->bank & 0xfc;

	if (data->bank != new_bank) {

		if (i2c_smbus_write_byte_data

		    (client, W83795_REG_BANKSEL, new_bank) >= 0)

			data->bank = new_bank;

		else {

	int err;



	/* If the same bank is already set, nothing to do */

	if ((data->bank & 0x07) == bank)

		return 0;



	/* Change to new bank, preserve all other bits */

	bank |= data->bank & ~0x07;

	err = i2c_smbus_write_byte_data(client, W83795_REG_BANKSEL, bank);

	if (err < 0) {

		dev_err(&client->dev,

				"set bank to %d failed, fall back "

				"to bank %d, read reg 0x%x error\n",

				new_bank, data->bank, reg);

			res = 0x0;	/* read 0x0 from the chip */

			goto END;

		}

			"Failed to set bank to %d, err %d\n",

			(int)bank, err);

		return err;

	}

	res = i2c_smbus_read_byte_data(client, reg & 0xff);

END:

	return res;

	data->bank = bank;



	return 0;

}



/* Must be called with data->update_lock held, except during initialization */

static int w83795_write(struct i2c_client *client, u16 reg, u8 value)

static u8 w83795_read(struct i2c_client *client, u16 reg)

{

	struct w83795_data *data = i2c_get_clientdata(client);

	int res;

	u8 new_bank = reg >> 8;



	new_bank |= data->bank & 0xfc;

	if (data->bank != new_bank) {

		res = i2c_smbus_write_byte_data(client, W83795_REG_BANKSEL,

						new_bank);

		if (res >= 0)

			data->bank = new_bank;

		else {

	int err;



	err = w83795_set_bank(client, reg >> 8);

	if (err < 0)

		return 0x00;	/* Arbitrary */



	err = i2c_smbus_read_byte_data(client, reg & 0xff);

	if (err < 0) {

		dev_err(&client->dev,

				"set bank to %d failed, fall back "

				"to bank %d, write reg 0x%x error\n",

				new_bank, data->bank, reg);

			goto END;

			"Failed to read from register 0x%03x, err %d\n",

			(int)reg, err);

		return 0x00;	/* Arbitrary */

	}

	return err;

}



	res = i2c_smbus_write_byte_data(client, reg & 0xff, value);

END:

	return res;

/* Must be called with data->update_lock held, except during initialization */

static int w83795_write(struct i2c_client *client, u16 reg, u8 value)

{

	int err;



	err = w83795_set_bank(client, reg >> 8);

	if (err < 0)

		return err;



	err = i2c_smbus_write_byte_data(client, reg & 0xff, value);

	if (err < 0)

		dev_err(&client->dev,

			"Failed to write to register 0x%03x, err %d\n",

			(int)reg, err);

	return err;

}



static struct w83795_data *w83795_update_device(struct device *dev)