Add optional reset-gpios pin control. If present, de-assert the specified reset gpio pin to bring the chip out of reset.
Signed-off-by: Steve Longerbeam <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Alexandre Courbot <[email protected]> Cc: [email protected] Cc: [email protected] -- v2: - Specify that reset signal to PCA953x chip is active low, in binding doc. - reorder includes in gpio-pca953x.c. - remove dev_err() on devm_gpiod_get_optional() error return. --- Documentation/devicetree/bindings/gpio/gpio-pca953x.txt | 4 ++++ drivers/gpio/gpio-pca953x.c | 9 +++++++++ 2 files changed, 13 insertions(+) diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt index 08dd15f..e639357 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt @@ -29,6 +29,10 @@ Required properties: onsemi,pca9654 exar,xra1202 +Optional properties: + - reset-gpios: GPIO specification for the RESET input. This is an + active low signal to the PCA953x. + Example: diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index d5d72d8..d44232a 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -14,6 +14,7 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/interrupt.h> #include <linux/i2c.h> #include <linux/platform_data/pca953x.h> @@ -754,8 +755,16 @@ static int pca953x_probe(struct i2c_client *client, invert = pdata->invert; chip->names = pdata->names; } else { + struct gpio_desc *reset_gpio; + chip->gpio_start = -1; irq_base = 0; + + /* See if we need to de-assert a reset pin */ + reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(reset_gpio)) + return PTR_ERR(reset_gpio); } chip->client = client; -- 2.7.4
