drm/msm/hdmi: simplify extp clock handling

With the extp being the only "power" clock left, remove the surrounding
loops and handle the extp clock directly.

Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/651710/
Link: https://lore.kernel.org/r/20250505-fd-hdmi-hpd-v5-4-48541f76318c@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Author: lumag

drivers/gpu/drm/msm/hdmi/hdmi.c

@@ -233,13 +233,11 @@ static const struct hdmi_platform_config hdmi_tx_8960_config = {
 };
 
 static const char * const pwr_reg_names_8x74[] = {"core-vdda", "core-vcc"};
-static const char * const pwr_clk_names_8x74[] = {"extp"};
 static const char * const hpd_clk_names_8x74[] = {"iface", "core", "mdp_core", "alt_iface"};
 static unsigned long hpd_clk_freq_8x74[] = {0, 19200000, 0, 0};
 
 static const struct hdmi_platform_config hdmi_tx_8974_config = {
 		HDMI_CFG(pwr_reg, 8x74),
-		HDMI_CFG(pwr_clk, 8x74),
 		HDMI_CFG(hpd_clk, 8x74),
 		.hpd_freq      = hpd_clk_freq_8x74,
 };
@@ -369,24 +367,10 @@ static int msm_hdmi_dev_probe(struct platform_device *pdev)
 		hdmi->hpd_clks[i] = clk;
 	}
 
-	hdmi->pwr_clks = devm_kcalloc(&pdev->dev,
-				      config->pwr_clk_cnt,
-				      sizeof(hdmi->pwr_clks[0]),
-				      GFP_KERNEL);
-	if (!hdmi->pwr_clks)
-		return -ENOMEM;
-
-	for (i = 0; i < config->pwr_clk_cnt; i++) {
-		struct clk *clk;
-
-		clk = msm_clk_get(pdev, config->pwr_clk_names[i]);
-		if (IS_ERR(clk))
-			return dev_err_probe(dev, PTR_ERR(clk),
-					     "failed to get pwr clk: %s\n",
-					     config->pwr_clk_names[i]);
-
-		hdmi->pwr_clks[i] = clk;
-	}
+	hdmi->extp_clk = devm_clk_get_optional(&pdev->dev, "extp");
+	if (IS_ERR(hdmi->extp_clk))
+		return dev_err_probe(dev, PTR_ERR(hdmi->extp_clk),
+				     "failed to get extp clock\n");
 
 	hdmi->hpd_gpiod = devm_gpiod_get_optional(&pdev->dev, "hpd", GPIOD_IN);
 	/* This will catch e.g. -EPROBE_DEFER */

drivers/gpu/drm/msm/hdmi/hdmi.h

@@ -50,7 +50,7 @@ struct hdmi {
 	struct regulator_bulk_data *hpd_regs;
 	struct regulator_bulk_data *pwr_regs;
 	struct clk **hpd_clks;
-	struct clk **pwr_clks;
+	struct clk *extp_clk;
 
 	struct gpio_desc *hpd_gpiod;
 
@@ -95,10 +95,6 @@ struct hdmi_platform_config {
 	const char * const *hpd_clk_names;
 	const long unsigned *hpd_freq;
 	int hpd_clk_cnt;
-
-	/* clks that need to be on for screen pwr (ie pixel clk): */
-	const char * const *pwr_clk_names;
-	int pwr_clk_cnt;
 };
 
 struct hdmi_bridge {

drivers/gpu/drm/msm/hdmi/hdmi_bridge.c

@@ -19,29 +19,23 @@ static void msm_hdmi_power_on(struct drm_bridge *bridge)
 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
 	struct hdmi *hdmi = hdmi_bridge->hdmi;
 	const struct hdmi_platform_config *config = hdmi->config;
-	int i, ret;
+	int ret;
 
 	pm_runtime_get_sync(&hdmi->pdev->dev);
 
 	ret = regulator_bulk_enable(config->pwr_reg_cnt, hdmi->pwr_regs);
 	if (ret)
 		DRM_DEV_ERROR(dev->dev, "failed to enable pwr regulator: %d\n", ret);
 
-	if (config->pwr_clk_cnt > 0) {
+	if (hdmi->extp_clk) {
 		DBG("pixclock: %lu", hdmi->pixclock);
-		ret = clk_set_rate(hdmi->pwr_clks[0], hdmi->pixclock);
-		if (ret) {
-			DRM_DEV_ERROR(dev->dev, "failed to set pixel clk: %s (%d)\n",
-					config->pwr_clk_names[0], ret);
-		}
-	}
+		ret = clk_set_rate(hdmi->extp_clk, hdmi->pixclock);
+		if (ret)
+			DRM_DEV_ERROR(dev->dev, "failed to set extp clk rate: %d\n", ret);
 
-	for (i = 0; i < config->pwr_clk_cnt; i++) {
-		ret = clk_prepare_enable(hdmi->pwr_clks[i]);
-		if (ret) {
-			DRM_DEV_ERROR(dev->dev, "failed to enable pwr clk: %s (%d)\n",
-					config->pwr_clk_names[i], ret);
-		}
+		ret = clk_prepare_enable(hdmi->extp_clk);
+		if (ret)
+			DRM_DEV_ERROR(dev->dev, "failed to enable extp clk: %d\n", ret);
 	}
 }
 
@@ -51,15 +45,15 @@ static void power_off(struct drm_bridge *bridge)
 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
 	struct hdmi *hdmi = hdmi_bridge->hdmi;
 	const struct hdmi_platform_config *config = hdmi->config;
-	int i, ret;
+	int ret;
 
 	/* TODO do we need to wait for final vblank somewhere before
 	 * cutting the clocks?
 	 */
 	mdelay(16 + 4);
 
-	for (i = 0; i < config->pwr_clk_cnt; i++)
-		clk_disable_unprepare(hdmi->pwr_clks[i]);
+	if (hdmi->extp_clk)
+		clk_disable_unprepare(hdmi->extp_clk);
 
 	ret = regulator_bulk_disable(config->pwr_reg_cnt, hdmi->pwr_regs);
 	if (ret)
@@ -438,7 +432,6 @@ static enum drm_mode_status msm_hdmi_bridge_tmds_char_rate_valid(const struct dr
 {
 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
 	struct hdmi *hdmi = hdmi_bridge->hdmi;
-	const struct hdmi_platform_config *config = hdmi->config;
 	struct msm_drm_private *priv = bridge->dev->dev_private;
 	struct msm_kms *kms = priv->kms;
 	long actual;
@@ -451,8 +444,8 @@ static enum drm_mode_status msm_hdmi_bridge_tmds_char_rate_valid(const struct dr
 		actual = kms->funcs->round_pixclk(kms,
 						  tmds_rate,
 						  hdmi_bridge->hdmi->encoder);
-	else if (config->pwr_clk_cnt > 0)
-		actual = clk_round_rate(hdmi->pwr_clks[0], tmds_rate);
+	else if (hdmi->extp_clk)
+		actual = clk_round_rate(hdmi->extp_clk, tmds_rate);
 	else
 		actual = tmds_rate;