Make the pll-clock-frequency optional. If it's present, use it to maintain backwards compatibility with existing hardware. If it is absent, read clock rate of "sclk_mipi" to determine the rate. Since it can be optional, change the message from an error to dev_info. Signed-off-by: Adam Ford <aford173@xxxxxxxxx> Tested-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx> Tested-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx> Reviewed-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Reviewed-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx> Tested-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx> # imx8mm-icore --- drivers/gpu/drm/bridge/samsung-dsim.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c index ead922c3ce9f..307f1c20cfb9 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -1719,11 +1719,11 @@ static const struct mipi_dsi_host_ops samsung_dsim_ops = { }; static int samsung_dsim_of_read_u32(const struct device_node *np, - const char *propname, u32 *out_value) + const char *propname, u32 *out_value, bool optional) { int ret = of_property_read_u32(np, propname, out_value); - if (ret < 0) + if (ret < 0 && !optional) pr_err("%pOF: failed to get '%s' property\n", np, propname); return ret; @@ -1736,19 +1736,27 @@ static int samsung_dsim_parse_dt(struct samsung_dsim *dsi) u32 lane_polarities[5] = { 0 }; struct device_node *endpoint; int i, nr_lanes, ret; + struct clk *pll_clk; ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency", - &dsi->pll_clk_rate); - if (ret < 0) - return ret; + &dsi->pll_clk_rate, 1); + /* If it doesn't exist, read it from the clock instead of failing */ + if (ret < 0) { + dev_dbg(dev, "Using sclk_mipi for pll clock frequency\n"); + pll_clk = devm_clk_get(dev, "sclk_mipi"); + if (!IS_ERR(pll_clk)) + dsi->pll_clk_rate = clk_get_rate(pll_clk); + else + return PTR_ERR(pll_clk); + } ret = samsung_dsim_of_read_u32(node, "samsung,burst-clock-frequency", - &dsi->burst_clk_rate); + &dsi->burst_clk_rate, 0); if (ret < 0) return ret; ret = samsung_dsim_of_read_u32(node, "samsung,esc-clock-frequency", - &dsi->esc_clk_rate); + &dsi->esc_clk_rate, 0); if (ret < 0) return ret; -- 2.39.2