| Message ID | 1402178205-22697-37-git-send-email-steve_longerbeam@mentor.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Am Samstag, den 07.06.2014, 14:56 -0700 schrieb Steve Longerbeam: [...] > static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val, > @@ -735,6 +741,26 @@ static int pca953x_probe(struct i2c_client *client, > /* If I2C node has no interrupts property, disable GPIO interrupts */ > if (of_find_property(client->dev.of_node, "interrupts", NULL) == NULL) > irq_base = -1; > + > + /* see if we need to de-assert a reset pin */ > + ret = of_get_named_gpio_flags(client->dev.of_node, > + "reset-gpios", 0, > + &chip->reset_gpio_flags); > + if (gpio_is_valid(ret)) { > + chip->reset_gpio = ret; > + ret = devm_gpio_request_one(&client->dev, > + chip->reset_gpio, > + GPIOF_DIR_OUT, > + "pca953x_reset"); > + if (ret == 0) { > + /* bring chip out of reset */ > + dev_info(&client->dev, "releasing reset\n"); I think dev_dbg would be more appropriate. > + gpio_set_value(chip->reset_gpio, > + (chip->reset_gpio_flags == > + OF_GPIO_ACTIVE_LOW) ? 1 : 0); > + } You could use the gpiod API (include/gpio/consumer.h) here and have it do the polarity handling automatically. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index d550d8e..6e212f7 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -22,6 +22,7 @@ #include <linux/slab.h> #ifdef CONFIG_OF_GPIO #include <linux/of_platform.h> +#include <linux/of_gpio.h> #endif #define PCA953X_INPUT 0 @@ -98,6 +99,11 @@ struct pca953x_chip { struct gpio_chip gpio_chip; const char *const *names; int chip_type; + +#ifdef CONFIG_OF_GPIO + enum of_gpio_flags reset_gpio_flags; + int reset_gpio; +#endif }; static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val, @@ -735,6 +741,26 @@ static int pca953x_probe(struct i2c_client *client, /* If I2C node has no interrupts property, disable GPIO interrupts */ if (of_find_property(client->dev.of_node, "interrupts", NULL) == NULL) irq_base = -1; + + /* see if we need to de-assert a reset pin */ + ret = of_get_named_gpio_flags(client->dev.of_node, + "reset-gpios", 0, + &chip->reset_gpio_flags); + if (gpio_is_valid(ret)) { + chip->reset_gpio = ret; + ret = devm_gpio_request_one(&client->dev, + chip->reset_gpio, + GPIOF_DIR_OUT, + "pca953x_reset"); + if (ret == 0) { + /* bring chip out of reset */ + dev_info(&client->dev, "releasing reset\n"); + gpio_set_value(chip->reset_gpio, + (chip->reset_gpio_flags == + OF_GPIO_ACTIVE_LOW) ? 1 : 0); + } + } else if (ret == -EPROBE_DEFER) + return ret; #endif }
Add optional reset-gpios property. If present, de-assert the specified reset gpio pin to bring the chip out of reset. Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com> --- drivers/gpio/gpio-pca953x.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)