drm/msm/dsi: Implement RPM suspend/resume callbacks

The bus clocks are always enabled/disabled along with the power
domain, so move it to the runtime suspend/resume ops. This cleans
up the clock code a bit. Get rid of the clk_mutex mutex since it
isn't needed.
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/dsi/dsi.c

@@ -161,12 +161,17 @@ static const struct of_device_id dt_match[] = {
 	{}
 };
 
+static const struct dev_pm_ops dsi_pm_ops = {
+	SET_RUNTIME_PM_OPS(msm_dsi_runtime_suspend, msm_dsi_runtime_resume, NULL)
+};
+
 static struct platform_driver dsi_driver = {
 	.probe = dsi_dev_probe,
 	.remove = dsi_dev_remove,
 	.driver = {
 		.name = "msm_dsi",
 		.of_match_table = dt_match,
+		.pm = &dsi_pm_ops,
 	},
 };
 

drivers/gpu/drm/msm/dsi/dsi.h

@@ -179,6 +179,8 @@ void msm_dsi_host_destroy(struct mipi_dsi_host *host);
 int msm_dsi_host_modeset_init(struct mipi_dsi_host *host,
 					struct drm_device *dev);
 int msm_dsi_host_init(struct msm_dsi *msm_dsi);
+int msm_dsi_runtime_suspend(struct device *dev);
+int msm_dsi_runtime_resume(struct device *dev);
 
 /* dsi phy */
 struct msm_dsi_phy;

drivers/gpu/drm/msm/dsi/dsi_host.c

@@ -135,7 +135,6 @@ struct msm_dsi_host {
 	struct completion video_comp;
 	struct mutex dev_mutex;
 	struct mutex cmd_mutex;
-	struct mutex clk_mutex;
 	spinlock_t intr_lock; /* Protect interrupt ctrl register */
 
 	u32 err_work_state;
@@ -458,6 +457,34 @@ static void dsi_bus_clk_disable(struct msm_dsi_host *msm_host)
 		clk_disable_unprepare(msm_host->bus_clks[i]);
 }
 
+int msm_dsi_runtime_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct msm_dsi *msm_dsi = platform_get_drvdata(pdev);
+	struct mipi_dsi_host *host = msm_dsi->host;
+	struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
+
+	if (!msm_host->cfg_hnd)
+		return 0;
+
+	dsi_bus_clk_disable(msm_host);
+
+	return 0;
+}
+
+int msm_dsi_runtime_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct msm_dsi *msm_dsi = platform_get_drvdata(pdev);
+	struct mipi_dsi_host *host = msm_dsi->host;
+	struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
+
+	if (!msm_host->cfg_hnd)
+		return 0;
+
+	return dsi_bus_clk_enable(msm_host);
+}
+
 static int dsi_link_clk_enable_6g(struct msm_dsi_host *msm_host)
 {
 	int ret;
@@ -599,35 +626,6 @@ static void dsi_link_clk_disable(struct msm_dsi_host *msm_host)
 	}
 }
 
-static int dsi_clk_ctrl(struct msm_dsi_host *msm_host, bool enable)
-{
-	int ret = 0;
-
-	mutex_lock(&msm_host->clk_mutex);
-	if (enable) {
-		ret = dsi_bus_clk_enable(msm_host);
-		if (ret) {
-			pr_err("%s: Can not enable bus clk, %d\n",
-				__func__, ret);
-			goto unlock_ret;
-		}
-		ret = dsi_link_clk_enable(msm_host);
-		if (ret) {
-			pr_err("%s: Can not enable link clk, %d\n",
-				__func__, ret);
-			dsi_bus_clk_disable(msm_host);
-			goto unlock_ret;
-		}
-	} else {
-		dsi_link_clk_disable(msm_host);
-		dsi_bus_clk_disable(msm_host);
-	}
-
-unlock_ret:
-	mutex_unlock(&msm_host->clk_mutex);
-	return ret;
-}
-
 static int dsi_calc_clk_rate(struct msm_dsi_host *msm_host)
 {
 	struct drm_display_mode *mode = msm_host->mode;
@@ -1702,6 +1700,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 	}
 
 	msm_host->pdev = pdev;
+	msm_dsi->host = &msm_host->base;
 
 	ret = dsi_host_parse_dt(msm_host);
 	if (ret) {
@@ -1758,7 +1757,6 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 	init_completion(&msm_host->video_comp);
 	mutex_init(&msm_host->dev_mutex);
 	mutex_init(&msm_host->cmd_mutex);
-	mutex_init(&msm_host->clk_mutex);
 	spin_lock_init(&msm_host->intr_lock);
 
 	/* setup workqueue */
@@ -1766,7 +1764,6 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 	INIT_WORK(&msm_host->err_work, dsi_err_worker);
 	INIT_WORK(&msm_host->hpd_work, dsi_hpd_worker);
 
-	msm_dsi->host = &msm_host->base;
 	msm_dsi->id = msm_host->id;
 
 	DBG("Dsi Host %d initialized", msm_host->id);
@@ -1788,7 +1785,6 @@ void msm_dsi_host_destroy(struct mipi_dsi_host *host)
 		msm_host->workqueue = NULL;
 	}
 
-	mutex_destroy(&msm_host->clk_mutex);
 	mutex_destroy(&msm_host->cmd_mutex);
 	mutex_destroy(&msm_host->dev_mutex);
 
@@ -1889,7 +1885,7 @@ int msm_dsi_host_xfer_prepare(struct mipi_dsi_host *host,
 	 * mdp clock need to be enabled to receive dsi interrupt
 	 */
 	pm_runtime_get_sync(&msm_host->pdev->dev);
-	dsi_clk_ctrl(msm_host, 1);
+	dsi_link_clk_enable(msm_host);
 
 	/* TODO: vote for bus bandwidth */
 
@@ -1919,7 +1915,7 @@ void msm_dsi_host_xfer_restore(struct mipi_dsi_host *host,
 
 	/* TODO: unvote for bus bandwidth */
 
-	dsi_clk_ctrl(msm_host, 0);
+	dsi_link_clk_disable(msm_host);
 	pm_runtime_put_autosuspend(&msm_host->pdev->dev);
 }
 
@@ -2169,8 +2165,11 @@ int msm_dsi_host_enable(struct mipi_dsi_host *host)
 	 * and only turned on before MDP START.
 	 * This part of code should be enabled once mdp driver support it.
 	 */
-	/* if (msm_panel->mode == MSM_DSI_CMD_MODE)
-		dsi_clk_ctrl(msm_host, 0); */
+	/* if (msm_panel->mode == MSM_DSI_CMD_MODE) {
+	 *	dsi_link_clk_disable(msm_host);
+	 *	pm_runtime_put_autosuspend(&msm_host->pdev->dev);
+	 * }
+	 */
 
 	return 0;
 }
@@ -2227,9 +2226,10 @@ int msm_dsi_host_power_on(struct mipi_dsi_host *host,
 	}
 
 	pm_runtime_get_sync(&msm_host->pdev->dev);
-	ret = dsi_clk_ctrl(msm_host, 1);
+	ret = dsi_link_clk_enable(msm_host);
 	if (ret) {
-		pr_err("%s: failed to enable clocks. ret=%d\n", __func__, ret);
+		pr_err("%s: failed to enable link clocks. ret=%d\n",
+		       __func__, ret);
 		goto fail_disable_reg;
 	}
 
@@ -2253,7 +2253,8 @@ int msm_dsi_host_power_on(struct mipi_dsi_host *host,
 	return 0;
 
 fail_disable_clk:
-	dsi_clk_ctrl(msm_host, 0);
+	dsi_link_clk_disable(msm_host);
+	pm_runtime_put_autosuspend(&msm_host->pdev->dev);
 fail_disable_reg:
 	dsi_host_regulator_disable(msm_host);
 unlock_ret:
@@ -2278,7 +2279,7 @@ int msm_dsi_host_power_off(struct mipi_dsi_host *host)
 
 	pinctrl_pm_select_sleep_state(&msm_host->pdev->dev);
 
-	dsi_clk_ctrl(msm_host, 0);
+	dsi_link_clk_disable(msm_host);
 	pm_runtime_put_autosuspend(&msm_host->pdev->dev);
 
 	dsi_host_regulator_disable(msm_host);