video: hx8357: Make IM pins optional
The IM pins of the HX8357 controller are used to define the interface
used to feed pixel stream to the LCD panel.
Most of the time, these pins are directly routed to either the ground or
the VCC to set their values.
Remove the need to assign GPIOs to these pins when we are in such a case.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/backlight/hx8357.c b/drivers/video/backlight/hx8357.c
index a0482b5..47237fa 100644
--- a/drivers/video/backlight/hx8357.c
+++ b/drivers/video/backlight/hx8357.c
@@ -76,6 +76,7 @@
unsigned reset;
struct spi_device *spi;
int state;
+ bool use_im_pins;
};
static u8 hx8357_seq_power[] = {
@@ -250,9 +251,11 @@
* Set the interface selection pins to SPI mode, with three
* wires
*/
- gpio_set_value_cansleep(lcd->im_pins[0], 1);
- gpio_set_value_cansleep(lcd->im_pins[1], 0);
- gpio_set_value_cansleep(lcd->im_pins[2], 1);
+ if (lcd->use_im_pins) {
+ gpio_set_value_cansleep(lcd->im_pins[0], 1);
+ gpio_set_value_cansleep(lcd->im_pins[1], 0);
+ gpio_set_value_cansleep(lcd->im_pins[2], 1);
+ }
/* Reset the screen */
gpio_set_value(lcd->reset, 1);
@@ -424,25 +427,32 @@
return -EINVAL;
}
- for (i = 0; i < HX8357_NUM_IM_PINS; i++) {
- lcd->im_pins[i] = of_get_named_gpio(spi->dev.of_node,
- "im-gpios", i);
- if (lcd->im_pins[i] == -EPROBE_DEFER) {
- dev_info(&spi->dev, "GPIO requested is not here yet, deferring the probe\n");
- return -EPROBE_DEFER;
- }
- if (!gpio_is_valid(lcd->im_pins[i])) {
- dev_err(&spi->dev, "Missing dt property: im-gpios\n");
- return -EINVAL;
- }
+ if (of_find_property(spi->dev.of_node, "im-gpios", NULL)) {
+ lcd->use_im_pins = 1;
- ret = devm_gpio_request_one(&spi->dev, lcd->im_pins[i],
- GPIOF_OUT_INIT_LOW, "im_pins");
- if (ret) {
- dev_err(&spi->dev, "failed to request gpio %d: %d\n",
- lcd->im_pins[i], ret);
- return -EINVAL;
+ for (i = 0; i < HX8357_NUM_IM_PINS; i++) {
+ lcd->im_pins[i] = of_get_named_gpio(spi->dev.of_node,
+ "im-gpios", i);
+ if (lcd->im_pins[i] == -EPROBE_DEFER) {
+ dev_info(&spi->dev, "GPIO requested is not here yet, deferring the probe\n");
+ return -EPROBE_DEFER;
+ }
+ if (!gpio_is_valid(lcd->im_pins[i])) {
+ dev_err(&spi->dev, "Missing dt property: im-gpios\n");
+ return -EINVAL;
+ }
+
+ ret = devm_gpio_request_one(&spi->dev, lcd->im_pins[i],
+ GPIOF_OUT_INIT_LOW,
+ "im_pins");
+ if (ret) {
+ dev_err(&spi->dev, "failed to request gpio %d: %d\n",
+ lcd->im_pins[i], ret);
+ return -EINVAL;
+ }
}
+ } else {
+ lcd->use_im_pins = 0;
}
lcdev = lcd_device_register("mxsfb", &spi->dev, lcd, &hx8357_ops);