drm/arm/malidp: Set the output_depth register in modeset

One needs to store the value of the OUTPUT_DEPTH that one has parsed from
device tree, so that it can be restored on system resume. This value is
set in the modeset function as this gets reset when the system suspends.
Signed-off-by: Ayan Kumar Halder <ayan.halder@arm.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>

drivers/gpu/drm/arm/malidp_drv.c

@@ -715,6 +715,7 @@ static int malidp_bind(struct device *dev)
 	for (i = 0; i < MAX_OUTPUT_CHANNELS; i++)
 		out_depth = (out_depth << 8) | (output_width[i] & 0xf);
 	malidp_hw_write(hwdev, out_depth, hwdev->hw->map.out_depth_base);
+	hwdev->output_color_depth = out_depth;
 
 	atomic_set(&malidp->config_valid, MALIDP_CONFIG_VALID_INIT);
 	init_waitqueue_head(&malidp->wq);

drivers/gpu/drm/arm/malidp_hw.c

@@ -244,6 +244,8 @@ static void malidp500_modeset(struct malidp_hw_device *hwdev, struct videomode *
 {
 	u32 val = 0;
 
+	malidp_hw_write(hwdev, hwdev->output_color_depth,
+		hwdev->hw->map.out_depth_base);
 	malidp_hw_clearbits(hwdev, MALIDP500_DC_CLEAR_MASK, MALIDP500_DC_CONTROL);
 	if (mode->flags & DISPLAY_FLAGS_HSYNC_HIGH)
 		val |= MALIDP500_HSYNCPOL;
@@ -520,6 +522,8 @@ static void malidp550_modeset(struct malidp_hw_device *hwdev, struct videomode *
 {
 	u32 val = MALIDP_DE_DEFAULT_PREFETCH_START;
 
+	malidp_hw_write(hwdev, hwdev->output_color_depth,
+		hwdev->hw->map.out_depth_base);
 	malidp_hw_write(hwdev, val, MALIDP550_DE_CONTROL);
 	/*
 	 * Mali-DP550 and Mali-DP650 encode the background color like this:

drivers/gpu/drm/arm/malidp_hw.h

@@ -230,6 +230,7 @@ struct malidp_hw_device {
 
 	u8 min_line_size;
 	u16 max_line_size;
+	u32 output_color_depth;
 
 	/* track the device PM state */
 	bool pm_suspended;