[Intel-gfx] [PATCH v4 4/4] drm/i915/bxt: add bxt dsi gpio element support

[Jani Nikula]

Request the GPIO by index through the consumer API. For now, use a quick
hack to store the already requested ones, simply because I have no idea
whether this actually works or not, and I have no way to test it.

Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
index b7772ff892e7..3ec8005ef84f 100644
--- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
+++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
@@ -29,6 +29,7 @@
 #include <drm/drm_edid.h>
 #include <drm/i915_drm.h>
 #include <drm/drm_panel.h>
+#include <linux/gpio.h>
 #include <linux/slab.h>
 #include <video/mipi_display.h>
 #include <asm/intel-mid.h>
@@ -295,6 +296,31 @@ static void chv_exec_gpio(struct drm_i915_private *dev_priv,
 	mutex_unlock(&dev_priv->sb_lock);
 }
 
+static void bxt_exec_gpio(struct drm_i915_private *dev_priv,
+			  u8 gpio_source, u8 gpio_index, bool value)
+{
+	/* XXX: this table is a quick ugly hack. */
+	static struct gpio_desc *bxt_gpio_table[U8_MAX + 1];
+	struct gpio_desc *gpio_desc = bxt_gpio_table[gpio_index];
+
+	if (!gpio_desc) {
+		gpio_desc = devm_gpiod_get_index(dev_priv->dev->dev,
+						 NULL, gpio_index,
+						 value ? GPIOD_OUT_LOW :
+						 GPIOD_OUT_HIGH);
+
+		if (IS_ERR_OR_NULL(gpio_desc)) {
+			DRM_ERROR("GPIO index %u request failed (%ld)\n",
+				  gpio_index, PTR_ERR(gpio_desc));
+			return;
+		}
+
+		bxt_gpio_table[gpio_index] = gpio_desc;
+	}
+
+	gpiod_set_value(gpio_desc, value);
+}
+
 static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
 {
 	struct drm_device *dev = intel_dsi->base.base.dev;
@@ -321,7 +347,7 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
 	else if (IS_CHERRYVIEW(dev_priv))
 		chv_exec_gpio(dev_priv, gpio_source, gpio_index, value);
 	else
-		DRM_DEBUG_KMS("GPIO element not supported on this platform\n");
+		bxt_exec_gpio(dev_priv, gpio_source, gpio_index, value);
 
 	return data;
 }
-- 
2.1.4