[PATCH v6 phy-next 12/28] drm/rockchip: dw_hdmi: avoid direct dereference of phy->dev.of_node
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: 2026-03-27 18:49:05
Also in:
dri-devel, linux-arm-kernel, linux-arm-msm, linux-can, linux-gpio, linux-ide, linux-media, linux-pci, linux-phy, linux-renesas-soc, linux-riscv, linux-rockchip, linux-samsung-soc, linux-scsi, linux-sunxi, linux-tegra, linux-usb, lkml, spacemit
Subsystem:
arm/rockchip soc support, drm drivers, drm drivers and misc gpu patches, drm drivers for rockchip, the rest · Maintainers:
Heiko Stuebner, David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Sandy Huang, Heiko Stübner, Andy Yan, Linus Torvalds
The dw_hdmi-rockchip driver validates pixel clock rates against the
HDMI PHY's internal clock provider on certain SoCs like RK3328.
This is currently achieved by dereferencing hdmi->phy->dev.of_node
to obtain the provider node, which violates the Generic PHY API's
encapsulation (the goal is for struct phy to be an opaque pointer
with a hidden definition, to be interacted with only using API
functions or NULL pointer checks, for the case where optional variants
of phy_get() did not find a PHY).
Refactor dw_hdmi_rockchip_bind() to perform a manual phandle lookup
on the "hdmi" PHY index within the controller's DT node. This provides
a parallel path to the clock provider's OF node without relying on the
internal structure of the struct phy handle.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Heiko Stueber <heiko@sntech.de>
---
Cc: Sandy Huang <hjc@rock-chips.com>
Cc: "Heiko Stübner" <heiko@sntech.de>
Cc: Andy Yan <andy.yan@rock-chips.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Simona Vetter <simona@ffwll.ch>
v4->v6: none
v3->v4: add commit message clarification of what is understood by
"opaque pointer"
v1->v3: none
---
drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 25 ++++++++++++---------
1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
index 0dc1eb5d2ae3..7abb42e486c0 100644
--- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c@@ -537,21 +537,22 @@ static int dw_hdmi_rockchip_bind(struct device *dev, struct device *master, void *data) { struct platform_device *pdev = to_platform_device(dev); + struct device_node *np = dev_of_node(dev); struct dw_hdmi_plat_data *plat_data; const struct of_device_id *match; struct drm_device *drm = data; struct drm_encoder *encoder; struct rockchip_hdmi *hdmi; - int ret; + int ret, index; - if (!pdev->dev.of_node) + if (!np) return -ENODEV; hdmi = devm_kzalloc(&pdev->dev, sizeof(*hdmi), GFP_KERNEL); if (!hdmi) return -ENOMEM; - match = of_match_node(dw_hdmi_rockchip_dt_ids, pdev->dev.of_node); + match = of_match_node(dw_hdmi_rockchip_dt_ids, np); plat_data = devm_kmemdup(&pdev->dev, match->data, sizeof(*plat_data), GFP_KERNEL); if (!plat_data)
@@ -564,9 +565,9 @@ static int dw_hdmi_rockchip_bind(struct device *dev, struct device *master, plat_data->priv_data = hdmi; encoder = &hdmi->encoder.encoder; - encoder->possible_crtcs = drm_of_find_possible_crtcs(drm, dev->of_node); + encoder->possible_crtcs = drm_of_find_possible_crtcs(drm, np); rockchip_drm_encoder_set_crtc_endpoint_id(&hdmi->encoder, - dev->of_node, 0, 0); + np, 0, 0); /* * If we failed to find the CRTC(s) which this encoder is
@@ -588,13 +589,17 @@ static int dw_hdmi_rockchip_bind(struct device *dev, struct device *master, return dev_err_probe(hdmi->dev, ret, "failed to get phy\n"); } - if (hdmi->phy) { + index = of_property_match_string(np, "phy-names", "hdmi"); + if (index >= 0) { struct of_phandle_args clkspec; - clkspec.np = hdmi->phy->dev.of_node; - hdmi->hdmiphy_clk = of_clk_get_from_provider(&clkspec); - if (IS_ERR(hdmi->hdmiphy_clk)) - hdmi->hdmiphy_clk = NULL; + if (!of_parse_phandle_with_args(np, "phys", "#phy-cells", index, + &clkspec)) { + hdmi->hdmiphy_clk = of_clk_get_from_provider(&clkspec); + of_node_put(clkspec.np); + if (IS_ERR(hdmi->hdmiphy_clk)) + hdmi->hdmiphy_clk = NULL; + } } if (hdmi->chip_data == &rk3568_chip_data) {
--
2.43.0