gpio: pcf857x: share 8/16 bit access functions

This patch adds 8/16 bit write/read functions,
and shared gpio input/output/set/get functions.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c
index 2d1de9e7e9bd921f9db099777ddebce6f19c7056..076e236d0da74b71734a3159bf287b4e11e04b0a 100644 (file)
--- a/drivers/gpio/gpio-pcf857x.c
+++ b/drivers/gpio/gpio-pcf857x.c
@@ -61,61 +61,28 @@ struct pcf857x {
        struct i2c_client       *client;
        struct mutex            lock;           /* protect 'out' */
        unsigned                out;            /* software latch */
+
+       int (*write)(struct i2c_client *client, unsigned data);
+       int (*read)(struct i2c_client *client);
 };
 
 /*-------------------------------------------------------------------------*/
 
 /* Talk to 8-bit I/O expander */
 
-static int pcf857x_input8(struct gpio_chip *chip, unsigned offset)
-{
-       struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
-       int             status;
-
-       mutex_lock(&gpio->lock);
-       gpio->out |= (1 << offset);
-       status = i2c_smbus_write_byte(gpio->client, gpio->out);
-       mutex_unlock(&gpio->lock);
-
-       return status;
-}
-
-static int pcf857x_get8(struct gpio_chip *chip, unsigned offset)
-{
-       struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
-       s32             value;
-
-       value = i2c_smbus_read_byte(gpio->client);
-       return (value < 0) ? 0 : (value & (1 << offset));
-}
-
-static int pcf857x_output8(struct gpio_chip *chip, unsigned offset, int value)
+static int i2c_write_le8(struct i2c_client *client, unsigned data)
 {
-       struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
-       unsigned        bit = 1 << offset;
-       int             status;
-
-       mutex_lock(&gpio->lock);
-       if (value)
-               gpio->out |= bit;
-       else
-               gpio->out &= ~bit;
-       status = i2c_smbus_write_byte(gpio->client, gpio->out);
-       mutex_unlock(&gpio->lock);
-
-       return status;
+       return i2c_smbus_write_byte(client, data);
 }
 
-static void pcf857x_set8(struct gpio_chip *chip, unsigned offset, int value)
+static int i2c_read_le8(struct i2c_client *client)
 {
-       pcf857x_output8(chip, offset, value);
+       return (int)i2c_smbus_read_byte(client);
 }
 
-/*-------------------------------------------------------------------------*/
-
 /* Talk to 16-bit I/O expander */
 
-static int i2c_write_le16(struct i2c_client *client, u16 word)
+static int i2c_write_le16(struct i2c_client *client, unsigned word)
 {
        u8 buf[2] = { word & 0xff, word >> 8, };
        int status;
@@ -135,29 +102,31 @@ static int i2c_read_le16(struct i2c_client *client)
        return (buf[1] << 8) | buf[0];
 }
 
-static int pcf857x_input16(struct gpio_chip *chip, unsigned offset)
+/*-------------------------------------------------------------------------*/
+
+static int pcf857x_input(struct gpio_chip *chip, unsigned offset)
 {
        struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
        int             status;
 
        mutex_lock(&gpio->lock);
        gpio->out |= (1 << offset);
-       status = i2c_write_le16(gpio->client, gpio->out);
+       status = gpio->write(gpio->client, gpio->out);
        mutex_unlock(&gpio->lock);
 
        return status;
 }
 
-static int pcf857x_get16(struct gpio_chip *chip, unsigned offset)
+static int pcf857x_get(struct gpio_chip *chip, unsigned offset)
 {
        struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
        int             value;
 
-       value = i2c_read_le16(gpio->client);
+       value = gpio->read(gpio->client);
        return (value < 0) ? 0 : (value & (1 << offset));
 }
 
-static int pcf857x_output16(struct gpio_chip *chip, unsigned offset, int value)
+static int pcf857x_output(struct gpio_chip *chip, unsigned offset, int value)
 {
        struct pcf857x  *gpio = container_of(chip, struct pcf857x, chip);
        unsigned        bit = 1 << offset;
@@ -168,15 +137,15 @@ static int pcf857x_output16(struct gpio_chip *chip, unsigned offset, int value)
                gpio->out |= bit;
        else
                gpio->out &= ~bit;
-       status = i2c_write_le16(gpio->client, gpio->out);
+       status = gpio->write(gpio->client, gpio->out);
        mutex_unlock(&gpio->lock);
 
        return status;
 }
 
-static void pcf857x_set16(struct gpio_chip *chip, unsigned offset, int value)
+static void pcf857x_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-       pcf857x_output16(chip, offset, value);
+       pcf857x_output(chip, offset, value);
 }
 
 /*-------------------------------------------------------------------------*/
@@ -200,10 +169,15 @@ static int pcf857x_probe(struct i2c_client *client,
 
        mutex_init(&gpio->lock);
 
-       gpio->chip.base = pdata ? pdata->gpio_base : -1;
-       gpio->chip.can_sleep = 1;
-       gpio->chip.dev = &client->dev;
-       gpio->chip.owner = THIS_MODULE;
+       gpio->chip.base                 = pdata ? pdata->gpio_base : -1;
+       gpio->chip.can_sleep            = 1;
+       gpio->chip.dev                  = &client->dev;
+       gpio->chip.owner                = THIS_MODULE;
+       gpio->chip.get                  = pcf857x_get;
+       gpio->chip.set                  = pcf857x_set;
+       gpio->chip.direction_input      = pcf857x_input;
+       gpio->chip.direction_output     = pcf857x_output;
+       gpio->chip.ngpio                = id->driver_data;
 
        /* NOTE:  the OnSemi jlc1562b is also largely compatible with
         * these parts, notably for output.  It has a low-resolution
@@ -216,12 +190,9 @@ static int pcf857x_probe(struct i2c_client *client,
         *
         * NOTE: we don't distinguish here between *4 and *4a parts.
         */
-       gpio->chip.ngpio = id->driver_data;
        if (gpio->chip.ngpio == 8) {
-               gpio->chip.direction_input = pcf857x_input8;
-               gpio->chip.get = pcf857x_get8;
-               gpio->chip.direction_output = pcf857x_output8;
-               gpio->chip.set = pcf857x_set8;
+               gpio->write     = i2c_write_le8;
+               gpio->read      = i2c_read_le8;
 
                if (!i2c_check_functionality(client->adapter,
                                I2C_FUNC_SMBUS_BYTE))
@@ -238,10 +209,8 @@ static int pcf857x_probe(struct i2c_client *client,
         * NOTE: we don't distinguish here between '75 and '75c parts.
         */
        } else if (gpio->chip.ngpio == 16) {
-               gpio->chip.direction_input = pcf857x_input16;
-               gpio->chip.get = pcf857x_get16;
-               gpio->chip.direction_output = pcf857x_output16;
-               gpio->chip.set = pcf857x_set16;
+               gpio->write     = i2c_write_le16;
+               gpio->read      = i2c_read_le16;
 
                if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
                        status = -EIO;