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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Bartosz Golaszewski 2016-09-09 11:17:36 +02:00 committed by Linus Walleij
parent 7acc66e371
commit c6e3cf01d3

View file

@ -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_8(struct pca953x_chip *chip, int reg, u8 *val)
{
int ret;
ret = i2c_smbus_read_byte_data(chip->client, reg);
*val = ret;
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;
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 {
ret = i2c_smbus_read_word_data(chip->client, reg << 1);
val[0] = (u16)ret & 0xFF;
val[1] = (u16)ret >> 8;
}
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)