[PATCH v7 06/17] 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
repetition. Also, as part of the same function, handle reset control
(de)assertions, since that was already the case in the PM runtime
functions.

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.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
---
 drivers/gpu/drm/panfrost/panfrost_device.c | 123 +++++++++++++----------------
 1 file changed, 53 insertions(+), 70 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
index a9d9669912e0..9549ddb7854a 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.c
+++ b/drivers/gpu/drm/panfrost/panfrost_device.c
@@ -27,18 +27,53 @@ static int panfrost_reset_init(struct panfrost_device *pfdev)
 		return PTR_ERR(pfdev->rstc);
 	}
 
-	return reset_control_deassert(pfdev->rstc);
+	return 0;
+}
+
+static int panfrost_clk_enable_deassert_reset(struct panfrost_device *pfdev)
+{
+	int err;
+
+	err = reset_control_deassert(pfdev->rstc);
+	if (err)
+		return err;
+
+	err = clk_prepare_enable(pfdev->clock);
+	if (err)
+		goto assert_reset;
+
+	err = clk_prepare_enable(pfdev->bus_clock);
+	if (err)
+		goto disable_clock;
+
+	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);
+assert_reset:
+	reset_control_assert(pfdev->rstc);
+
+	return err;
 }
 
-static void panfrost_reset_fini(struct panfrost_device *pfdev)
+static void panfrost_clk_disable_assert_reset(struct panfrost_device *pfdev)
 {
+	clk_disable_unprepare(pfdev->bus_ace_clock);
+	clk_disable_unprepare(pfdev->bus_clock);
+	clk_disable_unprepare(pfdev->clock);
 	reset_control_assert(pfdev->rstc);
 }
 
 static int panfrost_clk_init(struct panfrost_device *pfdev)
 {
-	int err;
 	unsigned long rate;
+	int err = 0;
 
 	pfdev->clock = devm_clk_get(pfdev->base.dev, NULL);
 	if (IS_ERR(pfdev->clock)) {
@@ -49,53 +84,31 @@ 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);
-	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);
+		return err;
 	}
 
 	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);
-		if (err)
-			goto disable_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;
+		return err;
 	}
 
-	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;
+	return panfrost_clk_enable_deassert_reset(pfdev);
 }
 
 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_clk_disable_assert_reset(pfdev);
 }
 
 static int panfrost_regulator_init(struct panfrost_device *pfdev)
@@ -241,7 +254,7 @@ int panfrost_device_init(struct panfrost_device *pfdev)
 	err = panfrost_clk_init(pfdev);
 	if (err) {
 		dev_err(pfdev->base.dev, "clk init failed %d\n", err);
-		goto out_reset;
+		goto out_pm_domain;
 	}
 
 	err = panfrost_devfreq_init(pfdev);
@@ -317,8 +330,6 @@ int panfrost_device_init(struct panfrost_device *pfdev)
 	panfrost_devfreq_fini(pfdev);
 out_clk:
 	panfrost_clk_fini(pfdev);
-out_reset:
-	panfrost_reset_fini(pfdev);
 out_pm_domain:
 	panfrost_pm_domain_fini(pfdev);
 	pm_runtime_set_suspended(pfdev->base.dev);
@@ -338,7 +349,6 @@ void panfrost_device_fini(struct panfrost_device *pfdev)
 	panfrost_devfreq_fini(pfdev);
 	panfrost_regulator_fini(pfdev);
 	panfrost_clk_fini(pfdev);
-	panfrost_reset_fini(pfdev);
 	panfrost_pm_domain_fini(pfdev);
 
 	pm_runtime_set_suspended(pfdev->base.dev);
@@ -462,38 +472,15 @@ static int panfrost_device_runtime_resume(struct device *dev)
 	int ret;
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_RT)) {
-		ret = reset_control_deassert(pfdev->rstc);
+		ret = panfrost_clk_enable_deassert_reset(pfdev);
 		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;
 	}
 
 	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)
@@ -509,12 +496,8 @@ static int panfrost_device_runtime_suspend(struct device *dev)
 	panfrost_gpu_suspend_irq(pfdev);
 	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);
-		reset_control_assert(pfdev->rstc);
-	}
+	if (pfdev->comp->pm_features & BIT(GPU_PM_RT))
+		panfrost_clk_disable_assert_reset(pfdev);
 
 	return 0;
 }
@@ -536,11 +519,11 @@ static int panfrost_device_resume(struct device *dev)
 	}
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) {
-		ret = clk_enable(pfdev->clock);
+		ret = clk_prepare_enable(pfdev->clock);
 		if (ret)
 			goto err_clk;
 
-		ret = clk_enable(pfdev->bus_clock);
+		ret = clk_prepare_enable(pfdev->bus_clock);
 		if (ret)
 			goto err_bus_clk;
 	}
@@ -553,10 +536,10 @@ 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);
+		clk_disable_unprepare(pfdev->bus_clock);
 err_bus_clk:
 	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS))
-		clk_disable(pfdev->clock);
+		clk_disable_unprepare(pfdev->clock);
 err_clk:
 	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))
 		dev_pm_opp_set_opp(dev, NULL);
@@ -573,8 +556,8 @@ static int panfrost_device_suspend(struct device *dev)
 		return ret;
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) {
-		clk_disable(pfdev->bus_clock);
-		clk_disable(pfdev->clock);
+		clk_disable_unprepare(pfdev->bus_clock);
+		clk_disable_unprepare(pfdev->clock);
 	}
 
 	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))

-- 
2.55.0