diff options
| author | Fabio Estevam <fabio.estevam@nxp.com> | 2017-08-07 09:41:50 -0300 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2017-08-14 16:24:02 +0200 |
| commit | 7ebc194d0fd4bb0fc8c7aca4b500b5b24e733267 (patch) | |
| tree | af692d51b340c436bb39432618a21b977c29d983 | |
| parent | ee949b51e4165107fe4d9ed18c23829119078722 (diff) | |
| download | linux-7ebc194d0fd4bb0fc8c7aca4b500b5b24e733267.tar.bz2 | |
gpio: 74x164: Introduce 'enable-gpios' property
74HC595 has an /OE (output enable) pin that can be controlled by a GPIO.
Introduce an optional property called 'enable-gpios' that allows
controlling the /OE pin.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-74x164.txt | 3 | ||||
| -rw-r--r-- | drivers/gpio/gpio-74x164.c | 10 |
2 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-74x164.txt b/Documentation/devicetree/bindings/gpio/gpio-74x164.txt index ce1b2231bf5d..2a97553d8d76 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-74x164.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-74x164.txt @@ -12,6 +12,9 @@ Required properties: 1 = active low - registers-number: Number of daisy-chained shift registers +Optional properties: +- enable-gpios: GPIO connected to the OE (Output Enable) pin. + Example: gpio5: gpio5@0 { diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c index a6607faf2fdf..6b535ec858cc 100644 --- a/drivers/gpio/gpio-74x164.c +++ b/drivers/gpio/gpio-74x164.c @@ -9,6 +9,7 @@ * published by the Free Software Foundation. */ +#include <linux/gpio/consumer.h> #include <linux/init.h> #include <linux/mutex.h> #include <linux/spi/spi.h> @@ -31,6 +32,7 @@ struct gen_74x164_chip { * numbering, store the bytes in reverse order. */ u8 buffer[0]; + struct gpio_desc *gpiod_oe; }; static int __gen_74x164_write_config(struct gen_74x164_chip *chip) @@ -126,6 +128,13 @@ static int gen_74x164_probe(struct spi_device *spi) if (!chip) return -ENOMEM; + chip->gpiod_oe = devm_gpiod_get_optional(&spi->dev, "enable", + GPIOD_OUT_LOW); + if (IS_ERR(chip->gpiod_oe)) + return PTR_ERR(chip->gpiod_oe); + + gpiod_set_value_cansleep(chip->gpiod_oe, 1); + spi_set_drvdata(spi, chip); chip->gpio_chip.label = spi->modalias; @@ -164,6 +173,7 @@ static int gen_74x164_remove(struct spi_device *spi) { struct gen_74x164_chip *chip = spi_get_drvdata(spi); + gpiod_set_value_cansleep(chip->gpiod_oe, 0); gpiochip_remove(&chip->gpio_chip); mutex_destroy(&chip->lock); |