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[v2,2/2] gpio: 74x164: Introduce the 'registers-default' property

Message ID 20201230205916.8875-2-festevam@gmail.com
State New
Headers show
Series [v2,1/2] dt-bindings: gpio: 74x164: Introduce the 'registers-default' property | expand

Commit Message

Fabio Estevam Dec. 30, 2020, 8:59 p.m. UTC
From: Sandor Yu <sandor.yu@nxp.com>

On the imx7d-sdb board, there is one output pin of the 74x164 that
controls all peripherals power supply (PERI_3V).

This pin should be at high voltage level when the 74x164 is probed,
otherwise the modules dependent on PERI_3V3 will not be powered.

Add a new optional property called 'registers-default' that allows
describing the default output value for each shift register.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Changes since v1:
- Use the more generic device_property_read_u8_array(), which
also works in ACPI.

 drivers/gpio/gpio-74x164.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series


diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c
index 05637d585152..a11637518774 100644
--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -141,6 +141,9 @@  static int gen_74x164_probe(struct spi_device *spi)
 	chip->registers = nregs;
 	chip->gpio_chip.ngpio = GEN_74X164_NUMBER_GPIOS * chip->registers;
+	device_property_read_u8_array(&spi->dev, "registers-default",
+				      chip->buffer, chip->registers);
 	chip->gpio_chip.can_sleep = true;
 	chip->gpio_chip.parent = &spi->dev;
 	chip->gpio_chip.owner = THIS_MODULE;