gpio: pca953x: Add optional reset gpio control
Add optional reset-gpios pin control. If present, de-assert the
specified reset gpio pin to bring the chip out of reset.
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.
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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;