[PATCH 6/7] RFT: drm/msm/hdmi: Bring up HDMI connector OFF

[Linus Walleij <linus.walleij@linaro.org>]

There is elaborate code in the HDMI connector handling to
leave the connector in the state it was at power-on and
only touch the GPIOs when the connector .enable() and
.disable() callbacks are called.

I don't think this is what we normally want, initialize
the connector as OFF (possibly saving power?) using the
appropriate GPIO descriptor flags. It will still be
switched on/off in the enable()/disable() connector
callback as before, but we can drop some strange surplus
code.

Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpu/drm/msm/hdmi/hdmi.c           | 19 ++++++++++++-----
 drivers/gpu/drm/msm/hdmi/hdmi_connector.c | 25 ++++++-----------------
 2 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/msm/hdmi/hdmi.c b/drivers/gpu/drm/msm/hdmi/hdmi.c
index c8e8268c76e2..7d87f8821d2f 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi.c
@@ -563,13 +563,22 @@ static int msm_hdmi_bind(struct device *dev, struct device *master, void *data)
 	for (i = 0; i < HDMI_MAX_NUM_GPIO; i++) {
 		const char *name = msm_hdmi_gpio_pdata[i].name;
 		struct gpio_desc *gpiod;
+		enum gpiod_flags flags;
 
 		/*
-		 * We are fetching the GPIO lines "as is" since the connector
-		 * code is enabling and disabling the lines. Until that point
-		 * the power-on default value will be kept.
+		 * Notice the inverse set up here: we initialize the connector
+		 * to OFF state.
 		 */
-		gpiod = devm_gpiod_get_optional(dev, name, GPIOD_ASIS);
+		if (msm_hdmi_gpio_pdata[i].output) {
+			if (msm_hdmi_gpio_pdata[i].value)
+				flags = GPIOD_OUT_LOW;
+			else
+				flags = GPIOD_OUT_HIGH;
+		} else {
+			flags = GPIOD_IN;
+		}
+
+		gpiod = devm_gpiod_get_optional(dev, name, flags);
 		/* This will catch e.g. -PROBE_DEFER */
 		if (IS_ERR(gpiod))
 			return PTR_ERR(gpiod);
@@ -583,7 +592,7 @@ static int msm_hdmi_bind(struct device *dev, struct device *master, void *data)
 			 * in the upstream bindings.
 			 */
 			if (sscanf(name, "qcom,hdmi-tx-%s", name3))
-				gpiod = devm_gpiod_get_optional(dev, name3, GPIOD_ASIS);
+				gpiod = devm_gpiod_get_optional(dev, name3, flags);
 			if (IS_ERR(gpiod))
 				return PTR_ERR(gpiod);
 			if (!gpiod)
diff --git a/drivers/gpu/drm/msm/hdmi/hdmi_connector.c b/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
index c4e9f6d7960f..89c64cc85027 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi_connector.c
@@ -86,16 +86,9 @@ static int gpio_config(struct hdmi *hdmi, bool on)
 		for (i = 0; i < HDMI_MAX_NUM_GPIO; i++) {
 			struct hdmi_gpio_data gpio = config->gpios[i];
 
-			if (gpio.gpiod) {
-				if (gpio.output) {
-					gpiod_direction_output(gpio.gpiod,
-							       gpio.value);
-				} else {
-					gpiod_direction_input(gpio.gpiod);
-					gpiod_set_value_cansleep(gpio.gpiod,
-								 gpio.value);
-				}
-			}
+			/* The value indicates the value for turning things on */
+			if (gpio.gpiod)
+				gpiod_set_value_cansleep(gpio.gpiod, gpio.value);
 		}
 
 		DBG("gpio on");
@@ -103,16 +96,10 @@ static int gpio_config(struct hdmi *hdmi, bool on)
 		for (i = 0; i < HDMI_MAX_NUM_GPIO; i++) {
 			struct hdmi_gpio_data gpio = config->gpios[i];
 
-			if (!gpio.gpiod)
-				continue;
-
-			if (gpio.output) {
-				int value = gpio.value ? 0 : 1;
-
-				gpiod_set_value_cansleep(gpio.gpiod, value);
-			}
+			/* The inverse value turns stuff off */
+			if (gpio.gpiod && gpio.output)
+				gpiod_set_value_cansleep(gpio.gpiod, !gpio.value);
 		};
-
 		DBG("gpio off");
 	}
 
-- 
2.20.1