diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/pca953x.c | 71 |
1 files changed, 54 insertions, 17 deletions
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c index ef1fe24bcbaf..92583cd4bffd 100644 --- a/drivers/gpio/pca953x.c +++ b/drivers/gpio/pca953x.c @@ -1,5 +1,5 @@ /* - * pca953x.c - 16-bit I/O port with interrupt and reset + * pca953x.c - 4/8/16 bit I/O ports * * Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com> * Copyright (C) 2007 Marvell International Ltd. @@ -18,13 +18,26 @@ #include <asm/gpio.h> +#define PCA953X_INPUT 0 +#define PCA953X_OUTPUT 1 +#define PCA953X_INVERT 2 +#define PCA953X_DIRECTION 3 -#define NR_PCA953X_GPIOS 16 +/* This is temporary - in 2.6.26 i2c_driver_data should replace it. */ +struct pca953x_desc { + char name[I2C_NAME_SIZE]; + unsigned long driver_data; +}; -#define PCA953X_INPUT 0 -#define PCA953X_OUTPUT 2 -#define PCA953X_INVERT 4 -#define PCA953X_DIRECTION 6 +static const struct pca953x_desc pca953x_descs[] = { + { "pca9534", 8, }, + { "pca9535", 16, }, + { "pca9536", 4, }, + { "pca9537", 4, }, + { "pca9538", 8, }, + { "pca9539", 16, }, + /* REVISIT several pca955x parts should work here too */ +}; struct pca953x_chip { unsigned gpio_start; @@ -40,17 +53,30 @@ struct pca953x_chip { */ static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val) { - if (i2c_smbus_write_word_data(chip->client, reg, val) < 0) - return -EIO; + int ret; + + if (chip->gpio_chip.ngpio <= 8) + ret = i2c_smbus_write_byte_data(chip->client, reg, val); else - return 0; + ret = i2c_smbus_write_word_data(chip->client, reg << 1, val); + + if (ret < 0) { + dev_err(&chip->client->dev, "failed writing register\n"); + return -EIO; + } + + return 0; } static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val) { int ret; - ret = i2c_smbus_read_word_data(chip->client, reg); + if (chip->gpio_chip.ngpio <= 8) + ret = i2c_smbus_read_byte_data(chip->client, reg); + else + ret = i2c_smbus_read_word_data(chip->client, reg << 1); + if (ret < 0) { dev_err(&chip->client->dev, "failed reading register\n"); return -EIO; @@ -148,7 +174,7 @@ static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) chip->reg_output = reg_val; } -static int pca953x_init_gpio(struct pca953x_chip *chip) +static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios) { struct gpio_chip *gc; @@ -160,22 +186,30 @@ static int pca953x_init_gpio(struct pca953x_chip *chip) gc->set = pca953x_gpio_set_value; gc->base = chip->gpio_start; - gc->ngpio = NR_PCA953X_GPIOS; - gc->label = "pca953x"; - - return gpiochip_add(gc); + gc->ngpio = gpios; + gc->label = chip->client->name; } static int __devinit pca953x_probe(struct i2c_client *client) { struct pca953x_platform_data *pdata; struct pca953x_chip *chip; - int ret; + int ret, i; + const struct pca953x_desc *id = NULL; pdata = client->dev.platform_data; if (pdata == NULL) return -ENODEV; + /* this loop vanishes when we get i2c_device_id */ + for (i = 0; i < ARRAY_SIZE(pca953x_descs); i++) + if (!strcmp(pca953x_descs[i].name, client->name)) { + id = pca953x_descs + i; + break; + } + if (!id) + return -ENODEV; + chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL); if (chip == NULL) return -ENOMEM; @@ -187,6 +221,8 @@ static int __devinit pca953x_probe(struct i2c_client *client) /* initialize cached registers from their original values. * we can't share this chip with another i2c master. */ + pca953x_setup_gpio(chip, id->driver_data); + ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output); if (ret) goto out_failed; @@ -200,7 +236,8 @@ static int __devinit pca953x_probe(struct i2c_client *client) if (ret) goto out_failed; - ret = pca953x_init_gpio(chip); + + ret = gpiochip_add(&chip->gpio_chip); if (ret) goto out_failed; |