| Message ID | 20230506010933.170939-4-aford173@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: bridge: samsung-dsim: Support variable clocking | expand |
On Fri, May 5, 2023 at 8:09 PM Adam Ford <aford173@gmail.com> wrote: > > 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. > > Signed-off-by: Adam Ford <aford173@gmail.com> > Tested-by: Chen-Yu Tsai <wenst@chromium.org> > Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de> > Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de> Sorry for the noise. I forgot to merge in the suggested updates for the messages so they don't look like errors. A V5 is coming once I merge and test the changes. adam > --- > drivers/gpu/drm/bridge/samsung-dsim.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c > index bf4b33d2de76..2dc02a9e37c0 100644 > --- a/drivers/gpu/drm/bridge/samsung-dsim.c > +++ b/drivers/gpu/drm/bridge/samsung-dsim.c > @@ -1726,12 +1726,20 @@ static int samsung_dsim_parse_dt(struct samsung_dsim *dsi) > { > struct device *dev = dsi->dev; > struct device_node *node = dev->of_node; > + struct clk *pll_clk; > int ret; > > ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency", > &dsi->pll_clk_rate); > - if (ret < 0) > - return ret; > + > + /* If it doesn't exist, read it from the clock instead of failing */ > + if (ret < 0) { > + 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); > -- > 2.39.2 >
diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c index bf4b33d2de76..2dc02a9e37c0 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -1726,12 +1726,20 @@ static int samsung_dsim_parse_dt(struct samsung_dsim *dsi) { struct device *dev = dsi->dev; struct device_node *node = dev->of_node; + struct clk *pll_clk; int ret; ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency", &dsi->pll_clk_rate); - if (ret < 0) - return ret; + + /* If it doesn't exist, read it from the clock instead of failing */ + if (ret < 0) { + 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);