drm/msm/hdmi: implement proper runtime PM handling

It is completely not obvious, but the so-called 'hpd' clocks and
regulators are required for the HDMI host to function properly. Merge
pwr and hpd regulators. Use regulators, clocks and pinctrl to implement
proper runtime PM callbacks.

Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/651715/
Link: https://lore.kernel.org/r/20250505-fd-hdmi-hpd-v5-9-48541f76318c@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Author: lumag

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

@@ -8,6 +8,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 
 #include <drm/drm_bridge_connector.h>
@@ -224,11 +225,11 @@ int msm_hdmi_modeset_init(struct hdmi *hdmi,
 	.item ## _names = item ##_names_ ## entry, \
 	.item ## _cnt   = ARRAY_SIZE(item ## _names_ ## entry)
 
-static const char * const hpd_reg_names_8960[] = {"core-vdda"};
+static const char * const pwr_reg_names_8960[] = {"core-vdda"};
 static const char * const hpd_clk_names_8960[] = {"core", "master_iface", "slave_iface"};
 
 static const struct hdmi_platform_config hdmi_tx_8960_config = {
-		HDMI_CFG(hpd_reg, 8960),
+		HDMI_CFG(pwr_reg, 8960),
 		HDMI_CFG(hpd_clk, 8960),
 };
 
@@ -318,20 +319,6 @@ static int msm_hdmi_dev_probe(struct platform_device *pdev)
 	if (hdmi->irq < 0)
 		return hdmi->irq;
 
-	hdmi->hpd_regs = devm_kcalloc(&pdev->dev,
-				      config->hpd_reg_cnt,
-				      sizeof(hdmi->hpd_regs[0]),
-				      GFP_KERNEL);
-	if (!hdmi->hpd_regs)
-		return -ENOMEM;
-
-	for (i = 0; i < config->hpd_reg_cnt; i++)
-		hdmi->hpd_regs[i].supply = config->hpd_reg_names[i];
-
-	ret = devm_regulator_bulk_get(&pdev->dev, config->hpd_reg_cnt, hdmi->hpd_regs);
-	if (ret)
-		return dev_err_probe(dev, ret, "failed to get hpd regulators\n");
-
 	hdmi->pwr_regs = devm_kcalloc(&pdev->dev,
 				      config->pwr_reg_cnt,
 				      sizeof(hdmi->pwr_regs[0]),
@@ -409,6 +396,48 @@ static void msm_hdmi_dev_remove(struct platform_device *pdev)
 	msm_hdmi_put_phy(hdmi);
 }
 
+static int msm_hdmi_runtime_suspend(struct device *dev)
+{
+	struct hdmi *hdmi = dev_get_drvdata(dev);
+	const struct hdmi_platform_config *config = hdmi->config;
+
+	clk_bulk_disable_unprepare(config->hpd_clk_cnt, hdmi->hpd_clks);
+
+	pinctrl_pm_select_sleep_state(dev);
+
+	regulator_bulk_disable(config->pwr_reg_cnt, hdmi->pwr_regs);
+
+	return 0;
+}
+
+static int msm_hdmi_runtime_resume(struct device *dev)
+{
+	struct hdmi *hdmi = dev_get_drvdata(dev);
+	const struct hdmi_platform_config *config = hdmi->config;
+	int ret;
+
+	ret = regulator_bulk_enable(config->pwr_reg_cnt, hdmi->pwr_regs);
+	if (ret)
+		return ret;
+
+	ret = pinctrl_pm_select_default_state(dev);
+	if (ret)
+		goto fail;
+
+	ret = clk_bulk_prepare_enable(config->hpd_clk_cnt, hdmi->hpd_clks);
+	if (ret)
+		goto fail;
+
+	return 0;
+
+fail:
+	pinctrl_pm_select_sleep_state(dev);
+
+	return ret;
+}
+
+DEFINE_RUNTIME_DEV_PM_OPS(msm_hdmi_pm_ops, msm_hdmi_runtime_suspend, msm_hdmi_runtime_resume, NULL);
+
 static const struct of_device_id msm_hdmi_dt_match[] = {
 	{ .compatible = "qcom,hdmi-tx-8998", .data = &hdmi_tx_8974_config },
 	{ .compatible = "qcom,hdmi-tx-8996", .data = &hdmi_tx_8974_config },
@@ -426,6 +455,7 @@ static struct platform_driver msm_hdmi_driver = {
 	.driver = {
 		.name = "hdmi_msm",
 		.of_match_table = msm_hdmi_dt_match,
+		.pm = &msm_hdmi_pm_ops,
 	},
 };
 

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

@@ -47,7 +47,6 @@ struct hdmi {
 	void __iomem *qfprom_mmio;
 	phys_addr_t mmio_phy_addr;
 
-	struct regulator_bulk_data *hpd_regs;
 	struct regulator_bulk_data *pwr_regs;
 	struct clk_bulk_data *hpd_clks;
 	struct clk *extp_clk;
@@ -83,10 +82,6 @@ struct hdmi {
 
 /* platform config data (ie. from DT, or pdata) */
 struct hdmi_platform_config {
-	/* regulators that need to be on for hpd: */
-	const char * const *hpd_reg_names;
-	int hpd_reg_cnt;
-
 	/* regulators that need to be on for screen pwr: */
 	const char * const *pwr_reg_names;
 	int pwr_reg_cnt;

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

@@ -18,15 +18,10 @@ static void msm_hdmi_power_on(struct drm_bridge *bridge)
 	struct drm_device *dev = bridge->dev;
 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
 	struct hdmi *hdmi = hdmi_bridge->hdmi;
-	const struct hdmi_platform_config *config = hdmi->config;
 	int ret;
 
 	pm_runtime_resume_and_get(&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 (hdmi->extp_clk) {
 		DBG("pixclock: %lu", hdmi->pixclock);
 		ret = clk_set_rate(hdmi->extp_clk, hdmi->pixclock);
@@ -41,11 +36,8 @@ static void msm_hdmi_power_on(struct drm_bridge *bridge)
 
 static void power_off(struct drm_bridge *bridge)
 {
-	struct drm_device *dev = bridge->dev;
 	struct hdmi_bridge *hdmi_bridge = to_hdmi_bridge(bridge);
 	struct hdmi *hdmi = hdmi_bridge->hdmi;
-	const struct hdmi_platform_config *config = hdmi->config;
-	int ret;
 
 	/* TODO do we need to wait for final vblank somewhere before
 	 * cutting the clocks?
@@ -55,10 +47,6 @@ static void power_off(struct drm_bridge *bridge)
 	if (hdmi->extp_clk)
 		clk_disable_unprepare(hdmi->extp_clk);
 
-	ret = regulator_bulk_disable(config->pwr_reg_cnt, hdmi->pwr_regs);
-	if (ret)
-		DRM_DEV_ERROR(dev->dev, "failed to disable pwr regulator: %d\n", ret);
-
 	pm_runtime_put(&hdmi->pdev->dev);
 }
 

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

@@ -64,36 +64,17 @@ int msm_hdmi_hpd_enable(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;
 	struct device *dev = &hdmi->pdev->dev;
 	uint32_t hpd_ctrl;
 	int ret;
 	unsigned long flags;
 
-	ret = regulator_bulk_enable(config->hpd_reg_cnt, hdmi->hpd_regs);
-	if (ret) {
-		DRM_DEV_ERROR(dev, "failed to enable hpd regulators: %d\n", ret);
-		goto fail;
-	}
-
-	ret = pinctrl_pm_select_default_state(dev);
-	if (ret) {
-		DRM_DEV_ERROR(dev, "pinctrl state chg failed: %d\n", ret);
-		goto fail;
-	}
-
 	if (hdmi->hpd_gpiod)
 		gpiod_set_value_cansleep(hdmi->hpd_gpiod, 1);
 
 	ret = pm_runtime_resume_and_get(dev);
-	if (ret) {
-		DRM_DEV_ERROR(dev, "runtime resume failed: %d\n", ret);
-		goto fail;
-	}
-
-	ret = clk_bulk_prepare_enable(config->hpd_clk_cnt, hdmi->hpd_clks);
 	if (ret)
-		goto fail;
+		return ret;
 
 	msm_hdmi_set_mode(hdmi, false);
 	msm_hdmi_phy_reset(hdmi);
@@ -119,32 +100,18 @@ int msm_hdmi_hpd_enable(struct drm_bridge *bridge)
 	spin_unlock_irqrestore(&hdmi->reg_lock, flags);
 
 	return 0;
-
-fail:
-	return ret;
 }
 
 void msm_hdmi_hpd_disable(struct hdmi *hdmi)
 {
-	const struct hdmi_platform_config *config = hdmi->config;
 	struct device *dev = &hdmi->pdev->dev;
-	int ret;
 
 	/* Disable HPD interrupt */
 	hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL, 0);
 
 	msm_hdmi_set_mode(hdmi, false);
 
-	clk_bulk_disable_unprepare(config->hpd_clk_cnt, hdmi->hpd_clks);
 	pm_runtime_put(dev);
-
-	ret = pinctrl_pm_select_sleep_state(dev);
-	if (ret)
-		dev_warn(dev, "pinctrl state chg failed: %d\n", ret);
-
-	ret = regulator_bulk_disable(config->hpd_reg_cnt, hdmi->hpd_regs);
-	if (ret)
-		dev_warn(dev, "failed to disable hpd regulator: %d\n", ret);
 }
 
 void msm_hdmi_hpd_irq(struct drm_bridge *bridge)
@@ -179,22 +146,15 @@ void msm_hdmi_hpd_irq(struct drm_bridge *bridge)
 
 static enum drm_connector_status detect_reg(struct hdmi *hdmi)
 {
-	const struct hdmi_platform_config *config = hdmi->config;
 	u32 hpd_int_status = 0;
 	int ret;
 
 	ret = pm_runtime_resume_and_get(&hdmi->pdev->dev);
 	if (ret)
 		goto out;
 
-	ret = clk_bulk_prepare_enable(config->hpd_clk_cnt, hdmi->hpd_clks);
-	if (ret)
-		goto out;
-
 	hpd_int_status = hdmi_read(hdmi, REG_HDMI_HPD_INT_STATUS);
 
-	clk_bulk_disable_unprepare(config->hpd_clk_cnt, hdmi->hpd_clks);
-
 out:
 	pm_runtime_put(&hdmi->pdev->dev);