[PATCH 5/7] drm/exynos/mixer: simplify poweron flag

[Andrzej Hajda]

The driver uses bool protected by mutex to track power state.
The patch replaces this combo with single bit and atomic bitops.

Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_mixer.c | 51 ++++++++++-------------------------
 1 file changed, 14 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
index 360a40b..2465b1d 100644
--- a/drivers/gpu/drm/exynos/exynos_mixer.c
+++ b/drivers/gpu/drm/exynos/exynos_mixer.c
@@ -85,18 +85,21 @@ enum mixer_version_id {
 	MXR_VER_128_0_0_184,
 };
 
+enum mixer_flag_bits {
+	MXR_BIT_POWERED,
+};
+
 struct mixer_context {
 	struct platform_device *pdev;
 	struct device		*dev;
 	struct drm_device	*drm_dev;
 	int			pipe;
+	unsigned long		flags;
 	bool			interlace;
-	bool			powered;
 	bool			vp_enabled;
 	bool			has_sclk;
 	u32			int_en;
 
-	struct mutex		mixer_mutex;
 	struct mixer_resources	mixer_res;
 	struct hdmi_win_data	win_data[MIXER_WIN_NR];
 	enum mixer_version_id	mxr_ver;
@@ -894,7 +897,7 @@ static int mixer_enable_vblank(struct exynos_drm_manager *mgr)
 	struct mixer_context *mixer_ctx = mgr->ctx;
 	struct mixer_resources *res = &mixer_ctx->mixer_res;
 
-	if (!mixer_ctx->powered) {
+	if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags)) {
 		mixer_ctx->int_en |= MXR_INT_EN_VSYNC;
 		return 0;
 	}
@@ -911,7 +914,7 @@ static void mixer_disable_vblank(struct exynos_drm_manager *mgr)
 	struct mixer_context *mixer_ctx = mgr->ctx;
 	struct mixer_resources *res = &mixer_ctx->mixer_res;
 
-	if (!mixer_ctx->powered) {
+	if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags)) {
 		mixer_ctx->int_en &= MXR_INT_EN_VSYNC;
 		return;
 	}
@@ -980,12 +983,8 @@ static void mixer_win_commit(struct exynos_drm_manager *mgr, int zpos)
 
 	DRM_DEBUG_KMS("win: %d\n", win);
 
-	mutex_lock(&mixer_ctx->mixer_mutex);
-	if (!mixer_ctx->powered) {
-		mutex_unlock(&mixer_ctx->mixer_mutex);
+	if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags))
 		return;
-	}
-	mutex_unlock(&mixer_ctx->mixer_mutex);
 
 	if (win > 1 && mixer_ctx->vp_enabled)
 		vp_video_buffer(mixer_ctx, win);
@@ -1004,13 +1003,10 @@ static void mixer_win_disable(struct exynos_drm_manager *mgr, int zpos)
 
 	DRM_DEBUG_KMS("win: %d\n", win);
 
-	mutex_lock(&mixer_ctx->mixer_mutex);
-	if (!mixer_ctx->powered) {
-		mutex_unlock(&mixer_ctx->mixer_mutex);
+	if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags)) {
 		mixer_ctx->win_data[win].resume = false;
 		return;
 	}
-	mutex_unlock(&mixer_ctx->mixer_mutex);
 
 	spin_lock_irqsave(&res->reg_slock, flags);
 	mixer_vsync_set_update(mixer_ctx, false);
@@ -1027,12 +1023,8 @@ static void mixer_wait_for_vblank(struct exynos_drm_manager *mgr)
 {
 	struct mixer_context *mixer_ctx = mgr->ctx;
 
-	mutex_lock(&mixer_ctx->mixer_mutex);
-	if (!mixer_ctx->powered) {
-		mutex_unlock(&mixer_ctx->mixer_mutex);
+	if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags))
 		return;
-	}
-	mutex_unlock(&mixer_ctx->mixer_mutex);
 
 	drm_vblank_get(mgr->crtc->dev, mixer_ctx->pipe);
 
@@ -1084,13 +1076,8 @@ static void mixer_poweron(struct exynos_drm_manager *mgr)
 	struct mixer_context *ctx = mgr->ctx;
 	struct mixer_resources *res = &ctx->mixer_res;
 
-	mutex_lock(&ctx->mixer_mutex);
-	if (ctx->powered) {
-		mutex_unlock(&ctx->mixer_mutex);
+	if (test_bit(MXR_BIT_POWERED, &ctx->flags))
 		return;
-	}
-
-	mutex_unlock(&ctx->mixer_mutex);
 
 	pm_runtime_get_sync(ctx->dev);
 
@@ -1101,9 +1088,7 @@ static void mixer_poweron(struct exynos_drm_manager *mgr)
 			clk_prepare_enable(res->sclk_mixer);
 	}
 
-	mutex_lock(&ctx->mixer_mutex);
-	ctx->powered = true;
-	mutex_unlock(&ctx->mixer_mutex);
+	set_bit(MXR_BIT_POWERED, &ctx->flags);
 
 	mixer_reg_writemask(res, MXR_STATUS, ~0, MXR_STATUS_SOFT_RESET);
 
@@ -1120,21 +1105,15 @@ static void mixer_poweroff(struct exynos_drm_manager *mgr)
 	struct mixer_context *ctx = mgr->ctx;
 	struct mixer_resources *res = &ctx->mixer_res;
 
-	mutex_lock(&ctx->mixer_mutex);
-	if (!ctx->powered) {
-		mutex_unlock(&ctx->mixer_mutex);
+	if (!test_bit(MXR_BIT_POWERED, &ctx->flags))
 		return;
-	}
-	mutex_unlock(&ctx->mixer_mutex);
 
 	mixer_stop(ctx);
 	mixer_window_suspend(mgr);
 
 	ctx->int_en = mixer_reg_read(res, MXR_INT_EN);
 
-	mutex_lock(&ctx->mixer_mutex);
-	ctx->powered = false;
-	mutex_unlock(&ctx->mixer_mutex);
+	clear_bit(MXR_BIT_POWERED, &ctx->flags);
 
 	clk_disable_unprepare(res->mixer);
 	if (ctx->vp_enabled) {
@@ -1269,8 +1248,6 @@ static int mixer_bind(struct device *dev, struct device *manager, void *data)
 		return -ENOMEM;
 	}
 
-	mutex_init(&ctx->mixer_mutex);
-
 	if (dev->of_node) {
 		const struct of_device_id *match;
 		match = of_match_node(mixer_match_types, dev->of_node);
-- 
1.9.1