On some SoCs the HDMI controller does not own its register window. The StarFive JH7110 documents one 64 KB block, u0_hdmitx, that holds both the controller and the PHY, so the parent device maps it and owns the regmap while the two children share it.
Use a regmap supplied by the parent device when there is one, and keep mapping our own resource when there is not, so platforms that own their register window are unaffected. Signed-off-by: Michal Wilczynski <[email protected]> --- drivers/gpu/drm/bridge/inno-hdmi.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/inno-hdmi.c b/drivers/gpu/drm/bridge/inno-hdmi.c index aab474740f7f57aa34007e6dac49e2414561593f..8bd771761180473d221f59d5c0cd2a636e96ac4c 100644 --- a/drivers/gpu/drm/bridge/inno-hdmi.c +++ b/drivers/gpu/drm/bridge/inno-hdmi.c @@ -397,6 +397,7 @@ struct inno_hdmi { struct clk *pclk; struct clk *refclk; void __iomem *regs; + struct regmap *regmap; struct regmap *grf; struct inno_hdmi_i2c *i2c; @@ -470,11 +471,25 @@ static int inno_hdmi_find_phy_config(struct inno_hdmi *hdmi, static inline u8 hdmi_readb(struct inno_hdmi *hdmi, u16 offset) { + u32 val; + + if (hdmi->regmap) { + if (regmap_read(hdmi->regmap, offset * 4, &val)) + return 0; + + return val; + } + return readl_relaxed(hdmi->regs + (offset) * 0x04); } static inline void hdmi_writeb(struct inno_hdmi *hdmi, u16 offset, u32 val) { + if (hdmi->regmap) { + regmap_write(hdmi->regmap, offset * 4, val); + return; + } + writel_relaxed(val, hdmi->regs + (offset) * 0x04); } @@ -1095,9 +1110,19 @@ struct inno_hdmi *inno_hdmi_probe(struct platform_device *pdev, hdmi->dev = dev; hdmi->plat_data = plat_data; - hdmi->regs = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(hdmi->regs)) - return ERR_CAST(hdmi->regs); + /* + * On platforms where the controller shares a register space with + * other blocks, the parent owns the regmap. Fall back to mapping + * our own resource where it does not. + */ + if (dev->parent) + hdmi->regmap = dev_get_regmap(dev->parent, NULL); + + if (!hdmi->regmap) { + hdmi->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(hdmi->regs)) + return ERR_CAST(hdmi->regs); + } hdmi->pclk = devm_clk_get_enabled(hdmi->dev, "pclk"); if (IS_ERR(hdmi->pclk)) { -- 2.34.1
