The current behavior is to try to get optional clocks and print a dev_err message in case of failure. This looks rather confusing and may increase with the amount of optional clocks.
We may need a cleaner way to handle per-device clocks but in the meantime, let's reduce the amount of dev_err messages during the probe.
Signed-off-by: Stephane Viau sviau@codeaurora.org --- Documentation/devicetree/bindings/drm/msm/mdp.txt | 3 ++- drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c | 27 ++++++++++++++--------- 2 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/Documentation/devicetree/bindings/drm/msm/mdp.txt b/Documentation/devicetree/bindings/drm/msm/mdp.txt index 1a0598e..0833eda 100644 --- a/Documentation/devicetree/bindings/drm/msm/mdp.txt +++ b/Documentation/devicetree/bindings/drm/msm/mdp.txt @@ -11,13 +11,14 @@ Required properties: - clock-names: the following clocks are required: * "core_clk" * "iface_clk" - * "lut_clk" * "src_clk" * "hdmi_clk" * "mpd_clk"
Optional properties: - gpus: phandle for gpu device +- clock-names: the following clocks are optional: + * "lut_clk"
Example:
diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c index e11028c6..61fcb41 100644 --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c @@ -454,15 +454,19 @@ static void read_hw_revision(struct mdp5_kms *mdp5_kms, }
static int get_clk(struct platform_device *pdev, struct clk **clkp, - const char *name) + const char *name, bool mandatory) { struct device *dev = &pdev->dev; struct clk *clk = devm_clk_get(dev, name); - if (IS_ERR(clk)) { + if (IS_ERR(clk) && mandatory) { dev_err(dev, "failed to get %s (%ld)\n", name, PTR_ERR(clk)); return PTR_ERR(clk); } - *clkp = clk; + if (IS_ERR(clk)) + DBG("skipping %s", name); + else + *clkp = clk; + return 0; }
@@ -516,25 +520,26 @@ struct msm_kms *mdp5_kms_init(struct drm_device *dev) goto fail; }
- ret = get_clk(pdev, &mdp5_kms->axi_clk, "bus_clk"); + /* mandatory clocks: */ + ret = get_clk(pdev, &mdp5_kms->axi_clk, "bus_clk", true); if (ret) goto fail; - ret = get_clk(pdev, &mdp5_kms->ahb_clk, "iface_clk"); + ret = get_clk(pdev, &mdp5_kms->ahb_clk, "iface_clk", true); if (ret) goto fail; - ret = get_clk(pdev, &mdp5_kms->src_clk, "core_clk_src"); + ret = get_clk(pdev, &mdp5_kms->src_clk, "core_clk_src", true); if (ret) goto fail; - ret = get_clk(pdev, &mdp5_kms->core_clk, "core_clk"); + ret = get_clk(pdev, &mdp5_kms->core_clk, "core_clk", true); if (ret) goto fail; - ret = get_clk(pdev, &mdp5_kms->lut_clk, "lut_clk"); - if (ret) - DBG("failed to get (optional) lut_clk clock"); - ret = get_clk(pdev, &mdp5_kms->vsync_clk, "vsync_clk"); + ret = get_clk(pdev, &mdp5_kms->vsync_clk, "vsync_clk", true); if (ret) goto fail;
+ /* optional clocks: */ + get_clk(pdev, &mdp5_kms->lut_clk, "lut_clk", false); + /* we need to set a default rate before enabling. Set a safe * rate first, then figure out hw revision, and then set a * more optimal rate: