Hdmi: add workaround to avoid blank screen for acer KG221Q monitor

When detect acer KG221Q monitor, adjust npll to double pixel clock.(1920x1080@75)

Change-Id: Ibe5323678f10b319bf9d3e2057638f4cbec7bbf6

Author: gary_gen

drivers/clk/rockchip/clk-pll.c

@@ -367,8 +367,10 @@ static const struct rockchip_pll_rate_table *rockchip_get_pll_settings(
 	const struct rockchip_pll_rate_table  *rate_table = pll->rate_table;
 	int i;
 	bool iex_monitor = false;
+	bool acer_kg221q_monitor = false;
 
 	iex_monitor = detect_iex_monitor();
+	acer_kg221q_monitor = detect_acer_kg221q_monitor();
 
 	for (i = 0; i < pll->rate_count; i++) {
 		if( (rate == 85750000) && !iex_monitor)
@@ -377,6 +379,8 @@ static const struct rockchip_pll_rate_table *rockchip_get_pll_settings(
 			continue;
 		if( (rate == 78750000) && !iex_monitor)
 			continue;
+		if( (rate == 170000000) && !acer_kg221q_monitor)
+			continue;
 		if (rate == rate_table[i].rate) {
 			if (i < pll->sel) {
 				pll->scaling = rate;

drivers/clk/rockchip/clk-rk3288.c

@@ -142,6 +142,7 @@ static struct rockchip_pll_rate_table rk3288_npll_rates[] = {
 	RK3066_PLL_RATE_NB(297000000, 2, 198, 8, 16),
 	RK3066_PLL_RATE_NB(270000000, 1, 135, 12, 32),
 	RK3066_PLL_RATE_NB(260000000, 1, 130, 12, 32),
+	RK3066_PLL_RATE_NB(170000000, 1, 170, 12, 32),//1920*1080@75 acer KG221Q
 	RK3066_PLL_RATE_NB(148500000, 1, 99, 16, 32),
 	RK3066_PLL_RATE_NB(146250000, 6, 585, 16, 32),
 	RK3066_PLL_RATE_NB(108000000, 1, 54, 12, 32),

drivers/clk/rockchip/clk.h

@@ -186,6 +186,7 @@ struct clk;
 #define RK3399_PMU_GATEDIS_CON(x)	((x) * 0x4 + 0x130)
 
 extern bool detect_iex_monitor(void);
+extern bool detect_acer_kg221q_monitor(void);
 
 enum rockchip_pll_type {
 	pll_rk3036,

drivers/gpu/drm/drm_edid.c

@@ -1268,6 +1268,9 @@ static const u8 iex_edid[] = {
 	0x24, 0xb8, 0x85, 0x01
 };
 
+static const u8 acer_kg221q_edid[] = {
+	0x04, 0x72, 0x8e, 0x05
+};
 /**
  * drm_edid_header_is_valid - sanity check the header of the base EDID block
  * @raw_edid: pointer to raw base EDID block
@@ -1303,6 +1306,21 @@ bool drm_dect_iex_edid(struct edid *edid)
 }
 EXPORT_SYMBOL(drm_dect_iex_edid);
 
+bool drm_dect_acer_kg221q_edid(struct edid *edid)
+{
+	int i, score = 0;
+	u8 *raw_edid = (u8 *)edid;
+	for (i = 0; i < sizeof(acer_kg221q_edid); i++)
+		if (raw_edid[8+i] == acer_kg221q_edid[i])
+			score++;
+
+	if (score == 4)
+		return true;
+	else
+		return false;
+}
+EXPORT_SYMBOL(drm_dect_acer_kg221q_edid);
+
 static int edid_fixup __read_mostly = 6;
 module_param_named(edid_fixup, edid_fixup, int, 0400);
 MODULE_PARM_DESC(edid_fixup,

drivers/gpu/drm/drm_probe_helper.c

@@ -57,6 +57,7 @@
 
 static bool drm_kms_helper_poll = true;
 static bool drm_iex_monitor = false;
+static bool drm_acer_kg221q_monitor = false;
 module_param_named(poll, drm_kms_helper_poll, bool, 0600);
 
 static enum drm_mode_status
@@ -265,6 +266,7 @@ static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connect
 	if (!strcmp(connector->name, "HDMI-A-1")) {
 		edid_manufacturer = (struct edid *) connector->edid_blob_ptr->data;
 		drm_iex_monitor = drm_dect_iex_edid(edid_manufacturer);
+		drm_acer_kg221q_monitor = drm_dect_acer_kg221q_edid(edid_manufacturer);
 	}
 	list_for_each_entry(mode, &connector->modes, head) {
 		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
@@ -280,6 +282,12 @@ bool detect_iex_monitor(void)
 }
 EXPORT_SYMBOL(detect_iex_monitor);
 
+bool detect_acer_kg221q_monitor(void)
+{
+	return drm_acer_kg221q_monitor;
+}
+EXPORT_SYMBOL(detect_acer_kg221q_monitor);
+
 /**
  * drm_helper_probe_single_connector_modes - get complete set of display modes
  * @connector: connector to probe

include/drm/drm_crtc.h

@@ -2012,6 +2012,7 @@ extern void drm_set_preferred_mode(struct drm_connector *connector,
 
 extern int drm_edid_header_is_valid(const u8 *raw_edid);
 extern bool drm_dect_iex_edid(struct edid *edid);
+extern bool drm_dect_acer_kg221q_edid(struct edid *edid);
 extern bool drm_edid_block_valid(u8 *raw_edid, int block, bool print_bad_edid,
 				 bool *edid_corrupt);
 extern bool drm_edid_is_valid(struct edid *edid);