From ae79c19049b75af476adcbcfda6fc29bd93fc6f8 Mon Sep 17 00:00:00 2001 From: Andreas Schallenberg Date: Wed, 9 May 2012 09:46:17 +0200 Subject: [PATCH] Add support for TCA6424A This patch extends the PCA953x driver to support TI's TCA6424A 24 bit I2C I/O expander. The patch is based on code by Michele Bevilacqua. Changes in v2: - Compare ngpio against 24 in both places, not >16 - Larger datatype now u32 instead of uint. Bit fields not used for struct members since their address is taken. - Be precise: TCA6424A (untested for older TCA6424) Signed-off-by: Andreas Schallenberg Acked-by: Linus Walleij Signed-off-by: Grant Likely --- drivers/gpio/gpio-pca953x.c | 43 ++++++++++++++++++++++++++----------- 1 file changed, 30 insertions(+), 13 deletions(-) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index d3f3e8f54561..1c313c710be3 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -28,6 +28,8 @@ #define PCA953X_INVERT 2 #define PCA953X_DIRECTION 3 +#define REG_ADDR_AI 0x80 + #define PCA957X_IN 0 #define PCA957X_INVRT 1 #define PCA957X_BKEN 2 @@ -63,15 +65,15 @@ static const struct i2c_device_id pca953x_id[] = { { "pca6107", 8 | PCA953X_TYPE | PCA_INT, }, { "tca6408", 8 | PCA953X_TYPE | PCA_INT, }, { "tca6416", 16 | PCA953X_TYPE | PCA_INT, }, - /* NYET: { "tca6424", 24, }, */ + { "tca6424", 24 | PCA953X_TYPE | PCA_INT, }, { } }; MODULE_DEVICE_TABLE(i2c, pca953x_id); struct pca953x_chip { unsigned gpio_start; - uint16_t reg_output; - uint16_t reg_direction; + u32 reg_output; + u32 reg_direction; struct mutex i2c_lock; #ifdef CONFIG_GPIO_PCA953X_IRQ @@ -89,12 +91,20 @@ struct pca953x_chip { int chip_type; }; -static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val) +static int pca953x_write_reg(struct pca953x_chip *chip, int reg, u32 val) { int ret = 0; if (chip->gpio_chip.ngpio <= 8) ret = i2c_smbus_write_byte_data(chip->client, reg, val); + else if (chip->gpio_chip.ngpio == 24) { + ret = i2c_smbus_write_word_data(chip->client, + (reg << 2) | REG_ADDR_AI, + val & 0xffff); + ret = i2c_smbus_write_byte_data(chip->client, + (reg << 2) + 2, + (val & 0xff0000) >> 16); + } else { switch (chip->chip_type) { case PCA953X_TYPE: @@ -121,12 +131,17 @@ static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val) return 0; } -static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val) +static int pca953x_read_reg(struct pca953x_chip *chip, int reg, u32 *val) { int ret; if (chip->gpio_chip.ngpio <= 8) ret = i2c_smbus_read_byte_data(chip->client, reg); + else if (chip->gpio_chip.ngpio == 24) { + ret = i2c_smbus_read_word_data(chip->client, reg << 2); + ret |= (i2c_smbus_read_byte_data(chip->client, + (reg << 2) + 2)<<16); + } else ret = i2c_smbus_read_word_data(chip->client, reg << 1); @@ -135,14 +150,14 @@ static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val) return ret; } - *val = (uint16_t)ret; + *val = (u32)ret; return 0; } static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off) { struct pca953x_chip *chip; - uint16_t reg_val; + uint reg_val; int ret, offset = 0; chip = container_of(gc, struct pca953x_chip, gpio_chip); @@ -173,7 +188,7 @@ static int pca953x_gpio_direction_output(struct gpio_chip *gc, unsigned off, int val) { struct pca953x_chip *chip; - uint16_t reg_val; + uint reg_val; int ret, offset = 0; chip = container_of(gc, struct pca953x_chip, gpio_chip); @@ -223,7 +238,7 @@ exit: static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off) { struct pca953x_chip *chip; - uint16_t reg_val; + u32 reg_val; int ret, offset = 0; chip = container_of(gc, struct pca953x_chip, gpio_chip); @@ -253,7 +268,7 @@ static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off) static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) { struct pca953x_chip *chip; - uint16_t reg_val; + u32 reg_val; int ret, offset = 0; chip = container_of(gc, struct pca953x_chip, gpio_chip); @@ -386,7 +401,7 @@ static struct irq_chip pca953x_irq_chip = { static uint16_t pca953x_irq_pending(struct pca953x_chip *chip) { - uint16_t cur_stat; + u32 cur_stat; uint16_t old_stat; uint16_t pending; uint16_t trigger; @@ -449,6 +464,7 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, { struct i2c_client *client = chip->client; int ret, offset = 0; + u32 temporary; if (irq_base != -1 && (id->driver_data & PCA_INT)) { @@ -462,7 +478,8 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, offset = PCA957X_IN; break; } - ret = pca953x_read_reg(chip, offset, &chip->irq_stat); + ret = pca953x_read_reg(chip, offset, &temporary); + chip->irq_stat = temporary; if (ret) goto out_failed; @@ -603,7 +620,7 @@ out: static int __devinit device_pca957x_init(struct pca953x_chip *chip, int invert) { int ret; - uint16_t val = 0; + u32 val = 0; /* Let every port in proper state, that could save power */ pca953x_write_reg(chip, PCA957X_PUPD, 0x0); -- 2.20.1