media: s5p-mfc: use clock gating only on mfc v5 hardware

Software clock gating causes unpredicted behavior of newer MFC hardware,
so use it only when working with v5 module.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Change-Id: I5a636b9c46b5e387da4d1c4f6dbb4adb583085e3

3 files changed, 23 insertions, 3 deletions

diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c
index a955eec71548..7af9facc85d4 100644
--- a/drivers/media/platform/s5p-mfc/s5p_mfc.c
+++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c
@@ -1340,6 +1340,7 @@ static struct s5p_mfc_variant mfc_drvdata_v5 = {
 	.fw_name[0]	= "s5p-mfc.fw",
 	.clk_names	= {"mfc", "sclk_mfc"},
 	.num_clocks	= 2,
+	.use_clock_gating = true,
 };
 
 static struct s5p_mfc_buf_size_v6 mfc_buf_size_v6 = {
diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
index 9ef00c485fb5..9a9d7332491e 100644
--- a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
+++ b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
@@ -200,6 +200,7 @@ struct s5p_mfc_pm {
 	const char	**clk_names;
 	struct clk	*clocks[MFC_MAX_CLOCKS];
 	int		num_clocks;
+	bool		use_clock_gating;
 
 	atomic_t	power;
 	struct device	*device;
@@ -239,6 +240,7 @@ struct s5p_mfc_variant {
 	char	*fw_name[MFC_FW_MAX_VERSIONS];
 	const char	*clk_names[MFC_MAX_CLOCKS];
 	int		num_clocks;
+	bool		use_clock_gating;
 };
 
 /**
diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c b/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c
index d21055e19a71..cdeed6731784 100644
--- a/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c
+++ b/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c
@@ -37,6 +37,7 @@ int s5p_mfc_init_pm(struct s5p_mfc_dev *dev)
 
 	pm->num_clocks = dev->variant->num_clocks;
 	pm->clk_names = dev->variant->clk_names;
+	pm->use_clock_gating = dev->variant->use_clock_gating;
 
 	/* clock control */
 	for (i = 0; i < pm->num_clocks; i++) {
@@ -73,6 +74,8 @@ int s5p_mfc_clock_on(void)
 	atomic_inc(&clk_ref);
 	mfc_debug(3, "+ %d\n", atomic_read(&clk_ref));
 #endif
+	if (!pm->use_clock_gating)
+		return 0;
 
 	for (i = 0; i < pm->num_clocks; i++) {
 		ret = clk_enable(pm->clocks[i]);
@@ -92,6 +95,9 @@ void s5p_mfc_clock_off(void)
 	atomic_dec(&clk_ref);
 	mfc_debug(3, "- %d\n", atomic_read(&clk_ref));
 #endif
+	if (!pm->use_clock_gating)
+		return;
+
 	for (i = pm->num_clocks - 1; i >= 0; i--)
 		clk_disable(pm->clocks[i]);
 }
@@ -109,7 +115,11 @@ int s5p_mfc_power_on(void)
 #endif
 	/* clock control */
 	for (i = 0; i < pm->num_clocks; i++) {
-		ret = clk_prepare(pm->clocks[i]);
+		if (pm->use_clock_gating)
+			ret = clk_prepare(pm->clocks[i]);
+		else
+			ret = clk_prepare_enable(pm->clocks[i]);
+
 		if (ret < 0) {
 			mfc_err("clock prepare failed for clock: %s\n",
 				pm->clk_names[i]);
@@ -121,7 +131,10 @@ int s5p_mfc_power_on(void)
 	return 0;
 err:
 	while (--i > 0)
-		clk_unprepare(pm->clocks[i]);
+		if (pm->use_clock_gating)
+			clk_disable(pm->clocks[i]);
+		else
+			clk_disable_unprepare(pm->clocks[i]);
 	pm_runtime_put(pm->device);
 	return ret;
 }
@@ -129,8 +142,12 @@ err:
 int s5p_mfc_power_off(void)
 {
 	int i;
+
 	for (i = 0; i < pm->num_clocks; i++)
-		clk_unprepare(pm->clocks[i]);
+		if (pm->use_clock_gating)
+			clk_unprepare(pm->clocks[i]);
+		else
+			clk_disable_unprepare(pm->clocks[i]);
 
 #ifdef CONFIG_PM
 	return pm_runtime_put_sync(pm->device);