Commit c6e3cf01 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski Committed by Linus Walleij
Browse files

gpio: pca953x: refactor pca953x_read_regs() 



Avoid the unnecessary if-else in pca953x_read_regs() by spltting the
routine into smaller, specialized functions and calling the right one
via a function pointer held in struct pca953x.

Signed-off-by: default avatarBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 7acc66e3

drivers/gpio/gpio-pca953x.c

+35 −14
Original line number Diff line number Diff line
@@ -137,6 +137,7 @@ struct pca953x_chip { 
	const struct pca953x_reg_config *regs;



	int (*write_regs)(struct pca953x_chip *, int, u8 *);

	int (*read_regs)(struct pca953x_chip *, int, u8 *);

};



static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val,
@@ -222,24 +223,41 @@ static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val) 
	return 0;

}



static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)

static int pca953x_read_regs_8(struct pca953x_chip *chip, int reg, u8 *val)

{

	int ret;



	if (chip->gpio_chip.ngpio <= 8) {

	ret = i2c_smbus_read_byte_data(chip->client, reg);

	*val = ret;

	} else if (chip->gpio_chip.ngpio >= 24) {

		int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);



		ret = i2c_smbus_read_i2c_block_data(chip->client,

					(reg << bank_shift) | REG_ADDR_AI,

					NBANK(chip), val);

	} else {

	return ret;

}



static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val)

{

	int ret;



	ret = i2c_smbus_read_word_data(chip->client, reg << 1);

	val[0] = (u16)ret & 0xFF;

	val[1] = (u16)ret >> 8;



	return ret;

}



static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val)

{

	int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);



	return i2c_smbus_read_i2c_block_data(chip->client,

					     (reg << bank_shift) | REG_ADDR_AI,

					     NBANK(chip), val);

}



static int pca953x_read_regs(struct pca953x_chip *chip, int reg, u8 *val)

{

	int ret;



	ret = chip->read_regs(chip, reg, val);

	if (ret < 0) {

		dev_err(&chip->client->dev, "failed reading register\n");

		return ret;
@@ -784,13 +802,16 @@ static int pca953x_probe(struct i2c_client *client, 


	if (chip->gpio_chip.ngpio <= 8) {

		chip->write_regs = pca953x_write_regs_8;

		chip->read_regs = pca953x_read_regs_8;

	} else if (chip->gpio_chip.ngpio >= 24) {

		chip->write_regs = pca953x_write_regs_24;

		chip->read_regs = pca953x_read_regs_24;

	} else {

		if (PCA_CHIP_TYPE(chip->driver_data) == PCA953X_TYPE)

			chip->write_regs = pca953x_write_regs_16;

		else

			chip->write_regs = pca957x_write_regs_16;

		chip->read_regs = pca953x_read_regs_16;

	}



	if (chip->chip_type == PCA953X_TYPE)

CRA Git | Maintained and supported by SUSTech CRA and CCSE