[PATCH v2 4/7] drm/rockchip: dsi: Support optional AHB clock

Alex Bee knaerzche at gmail.com
Thu May 9 05:07:12 PDT 2024


Some integrations of the IP additionally have an AHB clock which has to be
enabled before accessing the registers is possible.

Add support for it as an optional clock.

Signed-off-by: Alex Bee <knaerzche at gmail.com>
---
changes since v1:
 - new patch

 .../gpu/drm/rockchip/dw-mipi-dsi-rockchip.c   | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
index 4cc8ed8f4fbd..6ed64cc35275 100644
--- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
@@ -265,6 +265,7 @@ struct dw_mipi_dsi_rockchip {
 	struct clk *pllref_clk;
 	struct clk *grf_clk;
 	struct clk *phy_cfg_clk;
+	struct clk *ahb_clk;
 
 	/* dual-channel */
 	bool is_slave;
@@ -1153,7 +1154,15 @@ static int dw_mipi_dsi_dphy_init(struct phy *phy)
 			goto err_init;
 		}
 
+		ret = clk_prepare_enable(dsi->ahb_clk);
+		if (ret) {
+			clk_disable_unprepare(dsi->grf_clk);
+			clk_disable_unprepare(dsi->pclk);
+			goto err_init;
+		}
+
 		ret = dsi->cdata->dphy_rx_init(phy);
+		clk_disable_unprepare(dsi->ahb_clk);
 		clk_disable_unprepare(dsi->grf_clk);
 		clk_disable_unprepare(dsi->pclk);
 		if (ret < 0)
@@ -1240,6 +1249,12 @@ static int dw_mipi_dsi_dphy_power_on(struct phy *phy)
 		goto err_phy_cfg_clk;
 	}
 
+	ret = clk_prepare_enable(dsi->ahb_clk);
+	if (ret) {
+		DRM_DEV_ERROR(dsi->dev, "Failed to enable ahb_clk: %d\n", ret);
+		goto err_ahb_clk;
+	}
+
 	/* do soc-variant specific init */
 	if (dsi->cdata->dphy_rx_power_on) {
 		ret = dsi->cdata->dphy_rx_power_on(phy);
@@ -1269,6 +1284,8 @@ static int dw_mipi_dsi_dphy_power_on(struct phy *phy)
 	return ret;
 
 err_pwr_on:
+	clk_disable_unprepare(dsi->ahb_clk);
+err_ahb_clk:
 	clk_disable_unprepare(dsi->phy_cfg_clk);
 err_phy_cfg_clk:
 	clk_disable_unprepare(dsi->grf_clk);
@@ -1296,6 +1313,7 @@ static int dw_mipi_dsi_dphy_power_off(struct phy *phy)
 			DRM_DEV_ERROR(dsi->dev, "hardware-specific phy shutdown failed: %d\n", ret);
 	}
 
+	clk_disable_unprepare(dsi->ahb_clk);
 	clk_disable_unprepare(dsi->grf_clk);
 	clk_disable_unprepare(dsi->pclk);
 
@@ -1429,6 +1447,13 @@ static int dw_mipi_dsi_rockchip_probe(struct platform_device *pdev)
 		}
 	}
 
+	dsi->ahb_clk = devm_clk_get_optional(dev, "ahb");
+	if (IS_ERR(dsi->ahb_clk)) {
+		ret = PTR_ERR(dsi->ahb_clk);
+		DRM_DEV_ERROR(dev, "Unable to get ahb_clk: %d\n", ret);
+		return ret;
+	}
+
 	dsi->grf_regmap = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
 	if (IS_ERR(dsi->grf_regmap)) {
 		DRM_DEV_ERROR(dev, "Unable to get rockchip,grf\n");
-- 
2.43.2




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