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From:   Maxime Ripard <maxime@cerno.tech>
To:     Mike Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        dri-devel@lists.freedesktop.org,
        Daniel Vetter <daniel.vetter@intel.com>,
        David Airlie <airlied@linux.ie>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Maxime Ripard <maxime@cerno.tech>
Cc:     Maxime Ripard <mripard@kernel.org>, linux-clk@vger.kernel.org,
        Dave Stevenson <dave.stevenson@raspberrypi.com>,
        Phil Elwell <phil@raspberrypi.com>,
        Tim Gover <tim.gover@raspberrypi.com>,
        Dom Cobley <dom@raspberrypi.com>,
        Emma Anholt <emma@anholt.net>, linux-kernel@vger.kernel.org,
        Russell King <linux@armlinux.org.uk>
Subject: [PATCH v2 2/3] drm/vc4: hdmi: Convert to the new clock request API
Date:   Tue, 14 Sep 2021 11:35:14 +0200
Message-Id: <20210914093515.260031-3-maxime@cerno.tech>
In-Reply-To: <20210914093515.260031-1-maxime@cerno.tech>
References: <20210914093515.260031-1-maxime@cerno.tech>
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The new clock request API allows us to increase the rate of the HSM
clock to match our pixel rate requirements while decreasing it when
we're done, resulting in a better power-efficiency.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 15 ++++++++++-----
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 4a1115043114..099a94570e86 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -635,6 +635,8 @@ static void vc4_hdmi_encoder_post_crtc_powerdown(struct drm_encoder *encoder,
 		vc4_hdmi->variant->phy_disable(vc4_hdmi);
 
 	clk_disable_unprepare(vc4_hdmi->pixel_bvb_clock);
+	clk_request_done(vc4_hdmi->bvb_req);
+	clk_request_done(vc4_hdmi->hsm_req);
 	clk_disable_unprepare(vc4_hdmi->pixel_clock);
 
 	ret = pm_runtime_put(&vc4_hdmi->pdev->dev);
@@ -941,9 +943,9 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	 * pixel clock, but HSM ends up being the limiting factor.
 	 */
 	hsm_rate = max_t(unsigned long, 120000000, (pixel_rate / 100) * 101);
-	ret = clk_set_min_rate(vc4_hdmi->hsm_clock, hsm_rate);
-	if (ret) {
-		DRM_ERROR("Failed to set HSM clock rate: %d\n", ret);
+	vc4_hdmi->hsm_req = clk_request_start(vc4_hdmi->hsm_clock, hsm_rate);
+	if (IS_ERR(vc4_hdmi->hsm_req)) {
+		DRM_ERROR("Failed to set HSM clock rate: %ld\n", PTR_ERR(vc4_hdmi->hsm_req));
 		return;
 	}
 
@@ -956,9 +958,10 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	else
 		bvb_rate = 75000000;
 
-	ret = clk_set_min_rate(vc4_hdmi->pixel_bvb_clock, bvb_rate);
+	vc4_hdmi->bvb_req = clk_request_start(vc4_hdmi->pixel_bvb_clock, bvb_rate);
 	if (ret) {
-		DRM_ERROR("Failed to set pixel bvb clock rate: %d\n", ret);
+		DRM_ERROR("Failed to set pixel bvb clock rate: %ld\n", PTR_ERR(vc4_hdmi->bvb_req));
+		clk_request_done(vc4_hdmi->hsm_req);
 		clk_disable_unprepare(vc4_hdmi->pixel_clock);
 		return;
 	}
@@ -966,6 +969,8 @@ static void vc4_hdmi_encoder_pre_crtc_configure(struct drm_encoder *encoder,
 	ret = clk_prepare_enable(vc4_hdmi->pixel_bvb_clock);
 	if (ret) {
 		DRM_ERROR("Failed to turn on pixel bvb clock: %d\n", ret);
+		clk_request_done(vc4_hdmi->bvb_req);
+		clk_request_done(vc4_hdmi->hsm_req);
 		clk_disable_unprepare(vc4_hdmi->pixel_clock);
 		return;
 	}
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 33e9f665ab8e..683b2d8a3dca 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -176,6 +176,9 @@ struct vc4_hdmi {
 
 	struct reset_control *reset;
 
+	struct clk_request *bvb_req;
+	struct clk_request *hsm_req;
+
 	struct debugfs_regset32 hdmi_regset;
 	struct debugfs_regset32 hd_regset;
 };
-- 
2.31.1