From ccf9901ffec4b41a3a5c22580c4a7d358d88ca9f Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 1 Aug 2013 10:40:36 +0200 Subject: [PATCH] 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 Acked-by: Jingoo Han Signed-off-by: Tomi Valkeinen --- drivers/video/backlight/hx8357.c | 52 +++++++++++++++++++------------- 1 file changed, 31 insertions(+), 21 deletions(-) diff --git a/drivers/video/backlight/hx8357.c b/drivers/video/backlight/hx8357.c index a0482b567bfe..47237fa73b0c 100644 --- a/drivers/video/backlight/hx8357.c +++ b/drivers/video/backlight/hx8357.c @@ -76,6 +76,7 @@ struct hx8357_data { unsigned reset; struct spi_device *spi; int state; + bool use_im_pins; }; static u8 hx8357_seq_power[] = { @@ -250,9 +251,11 @@ static int hx8357_lcd_init(struct lcd_device *lcdev) * 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 @@ static int hx8357_probe(struct spi_device *spi) 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; + if (of_find_property(spi->dev.of_node, "im-gpios", NULL)) { + lcd->use_im_pins = 1; + + 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); -- 2.20.1