[PATCH v15 05/15] drm/panfrost: Consolidate device clock management and reset

["Adrián Larumbe" <adrian.larumbe@collabora.com>]

Gather all clock enables and disables into a single function to avoid
repetitions between driver init/fini and device resume/suspend, since
these clocks are always handled in bulk.

Also do clk (un)prepares and dis/enables at the same time, since the
clk_prepare_* family of functions can simply increase the refcnt of
an already prepared clock.

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panfrost/panfrost_device.c | 124 ++++++++++++++++-------------
 1 file changed, 69 insertions(+), 55 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
index b3a53504bd01..50f4713bfcfd 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.c
+++ b/drivers/gpu/drm/panfrost/panfrost_device.c
@@ -34,10 +34,46 @@ static void panfrost_reset_fini(struct panfrost_device *pfdev)
 	reset_control_assert(pfdev->rstc);
 }
 
-static int panfrost_clk_init(struct panfrost_device *pfdev)
+static int panfrost_clks_enable(struct panfrost_device *pfdev, bool on_resume)
 {
 	int err;
+
+	err = clk_prepare_enable(pfdev->clock);
+	if (err)
+		return err;
+
+	err = clk_prepare_enable(pfdev->bus_clock);
+	if (err)
+		goto disable_clock;
+
+	if (on_resume) {
+		err = clk_prepare_enable(pfdev->bus_ace_clock);
+		if (err)
+			goto disable_bus_clock;
+	}
+
+	return 0;
+
+disable_bus_clock:
+	clk_disable_unprepare(pfdev->bus_clock);
+disable_clock:
+	clk_disable_unprepare(pfdev->clock);
+
+	return err;
+}
+
+static void panfrost_clks_disable(struct panfrost_device *pfdev, bool on_suspend)
+{
+	if (on_suspend)
+		clk_disable_unprepare(pfdev->bus_ace_clock);
+	clk_disable_unprepare(pfdev->bus_clock);
+	clk_disable_unprepare(pfdev->clock);
+}
+
+static int panfrost_clk_init(struct panfrost_device *pfdev)
+{
 	unsigned long rate;
+	int err;
 
 	pfdev->clock = devm_clk_get(pfdev->base.dev, NULL);
 	if (IS_ERR(pfdev->clock)) {
@@ -48,53 +84,59 @@ static int panfrost_clk_init(struct panfrost_device *pfdev)
 	rate = clk_get_rate(pfdev->clock);
 	dev_info(pfdev->base.dev, "clock rate = %lu\n", rate);
 
-	err = clk_prepare_enable(pfdev->clock);
+	err = clk_prepare(pfdev->clock);
 	if (err)
 		return err;
 
 	pfdev->bus_clock = devm_clk_get_optional(pfdev->base.dev, "bus");
 	if (IS_ERR(pfdev->bus_clock)) {
-		dev_err(pfdev->base.dev, "get bus_clock failed %ld\n",
-			PTR_ERR(pfdev->bus_clock));
 		err = PTR_ERR(pfdev->bus_clock);
-		goto disable_clock;
+		dev_err(pfdev->base.dev, "get bus_clock failed %d\n", err);
+		goto unprepare_clock;
 	}
 
 	if (pfdev->bus_clock) {
 		rate = clk_get_rate(pfdev->bus_clock);
 		dev_info(pfdev->base.dev, "bus_clock rate = %lu\n", rate);
 
-		err = clk_prepare_enable(pfdev->bus_clock);
+		err = clk_prepare(pfdev->bus_clock);
 		if (err)
-			goto disable_clock;
+			goto unprepare_clock;
 	}
 
 	pfdev->bus_ace_clock = devm_clk_get_optional(pfdev->base.dev, "bus_ace");
 	if (IS_ERR(pfdev->bus_ace_clock)) {
 		err = PTR_ERR(pfdev->bus_ace_clock);
 		dev_err(pfdev->base.dev, "get bus_ace_clock failed %d\n", err);
-		goto disable_bus_clock;
+		goto unprepare_bus_clock;
 	}
 
-	err = clk_prepare_enable(pfdev->bus_ace_clock);
+	err = clk_prepare(pfdev->bus_ace_clock);
+	if (err)
+		goto unprepare_bus_clock;
+
+	err = panfrost_clks_enable(pfdev, true);
 	if (err)
-		goto disable_bus_clock;
+		goto unprepare_bus_ace_clock;
 
 	return 0;
 
-disable_bus_clock:
-	clk_disable_unprepare(pfdev->bus_clock);
-disable_clock:
-	clk_disable_unprepare(pfdev->clock);
+unprepare_bus_ace_clock:
+	clk_unprepare(pfdev->bus_ace_clock);
+unprepare_bus_clock:
+	clk_unprepare(pfdev->bus_clock);
+unprepare_clock:
+	clk_unprepare(pfdev->clock);
 
 	return err;
 }
 
 static void panfrost_clk_fini(struct panfrost_device *pfdev)
 {
-	clk_disable_unprepare(pfdev->bus_ace_clock);
-	clk_disable_unprepare(pfdev->bus_clock);
-	clk_disable_unprepare(pfdev->clock);
+	panfrost_clks_disable(pfdev, true);
+	clk_unprepare(pfdev->bus_ace_clock);
+	clk_unprepare(pfdev->bus_clock);
+	clk_unprepare(pfdev->clock);
 }
 
 static int panfrost_regulator_init(struct panfrost_device *pfdev)
@@ -436,34 +478,17 @@ static int panfrost_device_runtime_resume(struct device *dev)
 		if (ret)
 			return ret;
 
-		ret = clk_enable(pfdev->clock);
-		if (ret)
-			goto err_clk;
-
-		ret = clk_enable(pfdev->bus_clock);
-		if (ret)
-			goto err_bus_clk;
-
-		ret = clk_enable(pfdev->bus_ace_clock);
-		if (ret)
-			goto err_bus_ace_clk;
+		ret = panfrost_clks_enable(pfdev, true);
+		if (ret) {
+			reset_control_assert(pfdev->rstc);
+			return ret;
+		}
 	}
 
 	panfrost_device_reset(pfdev, true);
 	panfrost_devfreq_resume(pfdev);
 
 	return 0;
-
-err_bus_ace_clk:
-	if (pfdev->comp->pm_features & BIT(GPU_PM_RT))
-		clk_disable(pfdev->bus_clock);
-err_bus_clk:
-	if (pfdev->comp->pm_features & BIT(GPU_PM_RT))
-		clk_disable(pfdev->clock);
-err_clk:
-	if (pfdev->comp->pm_features & BIT(GPU_PM_RT))
-		reset_control_assert(pfdev->rstc);
-	return ret;
 }
 
 static int panfrost_device_runtime_suspend(struct device *dev)
@@ -480,9 +505,7 @@ static int panfrost_device_runtime_suspend(struct device *dev)
 	panfrost_gpu_power_off(pfdev);
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_RT)) {
-		clk_disable(pfdev->bus_ace_clock);
-		clk_disable(pfdev->bus_clock);
-		clk_disable(pfdev->clock);
+		panfrost_clks_disable(pfdev, true);
 		reset_control_assert(pfdev->rstc);
 	}
 
@@ -506,13 +529,9 @@ static int panfrost_device_resume(struct device *dev)
 	}
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) {
-		ret = clk_enable(pfdev->clock);
+		ret = panfrost_clks_enable(pfdev, false);
 		if (ret)
 			goto err_clk;
-
-		ret = clk_enable(pfdev->bus_clock);
-		if (ret)
-			goto err_bus_clk;
 	}
 
 	ret = pm_runtime_force_resume(dev);
@@ -523,10 +542,7 @@ static int panfrost_device_resume(struct device *dev)
 
 err_resume:
 	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS))
-		clk_disable(pfdev->bus_clock);
-err_bus_clk:
-	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS))
-		clk_disable(pfdev->clock);
+		panfrost_clks_disable(pfdev, false);
 err_clk:
 	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))
 		dev_pm_opp_set_opp(dev, NULL);
@@ -542,10 +558,8 @@ static int panfrost_device_suspend(struct device *dev)
 	if (ret)
 		return ret;
 
-	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) {
-		clk_disable(pfdev->bus_clock);
-		clk_disable(pfdev->clock);
-	}
+	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS))
+		panfrost_clks_disable(pfdev, false);
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))
 		dev_pm_opp_set_opp(dev, NULL);

-- 
2.55.0