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drm: bridge: samsung-dsim: Fetch pll-clock-frequency automatically

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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@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>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-4-aford173@gmail.com
This commit is contained in:
Adam Ford 2023-05-25 22:05:55 -05:00 committed by Neil Armstrong
parent 54f1a83c72
commit 33d8d14c83
1 changed files with 15 additions and 7 deletions
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22
drivers/gpu/drm/bridge/samsung-dsim.c
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@ -1740,11 +1740,11 @@ static const struct mipi_dsi_host_ops samsung_dsim_ops = {
}; };
static int samsung_dsim_of_read_u32(const struct device_node *np, 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); 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); pr_err("%pOF: failed to get '%s' property\n", np, propname);
return ret; return ret;
@ -1757,19 +1757,27 @@ static int samsung_dsim_parse_dt(struct samsung_dsim *dsi)
u32 lane_polarities[5] = { 0 }; u32 lane_polarities[5] = { 0 };
struct device_node *endpoint; struct device_node *endpoint;
int i, nr_lanes, ret; int i, nr_lanes, ret;
struct clk *pll_clk;
ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency", ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency",
&dsi->pll_clk_rate); &dsi->pll_clk_rate, 1);
if (ret < 0) /* If it doesn't exist, read it from the clock instead of failing */
return ret; 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", ret = samsung_dsim_of_read_u32(node, "samsung,burst-clock-frequency",
&dsi->burst_clk_rate); &dsi->burst_clk_rate, 0);
if (ret < 0) if (ret < 0)
return ret; return ret;
ret = samsung_dsim_of_read_u32(node, "samsung,esc-clock-frequency", ret = samsung_dsim_of_read_u32(node, "samsung,esc-clock-frequency",
&dsi->esc_clk_rate); &dsi->esc_clk_rate, 0);
if (ret < 0) if (ret < 0)
return ret; return ret;