diff options
author | Thierry Reding <treding@nvidia.com> | 2018-11-29 19:24:34 +0300 |
---|---|---|
committer | Thierry Reding <treding@nvidia.com> | 2018-11-29 19:25:21 +0300 |
commit | 0cffbde2e318cc1214486a84be0f31045b1fa493 (patch) | |
tree | 2ad8dab4cc1f4a2849c5da84a56e8f256debb862 /drivers/gpu/drm/tegra/hub.c | |
parent | d6b9bc025859521dae719d8fb8278b0c39b34861 (diff) | |
download | linux-0cffbde2e318cc1214486a84be0f31045b1fa493.tar.xz |
drm/tegra: hub: Enable all required clocks
The display architecture on Tegra186 and Tegra194 requires that there be
some valid clock on all domains before accessing any display register. A
further requirement is that in addition to the host1x, hub, disp and dsc
clocks, all the head clocks (pclk0-2 on Tegra186 or pclk0-3 on Tegra194)
must also be enabled.
Implement this logic within the display hub driver to ensure the clocks
are always enabled at the right time.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'drivers/gpu/drm/tegra/hub.c')
-rw-r--r-- | drivers/gpu/drm/tegra/hub.c | 48 |
1 files changed, 46 insertions, 2 deletions
diff --git a/drivers/gpu/drm/tegra/hub.c b/drivers/gpu/drm/tegra/hub.c index 6112d9042979..922a48d5a483 100644 --- a/drivers/gpu/drm/tegra/hub.c +++ b/drivers/gpu/drm/tegra/hub.c @@ -742,7 +742,9 @@ static const struct host1x_client_ops tegra_display_hub_ops = { static int tegra_display_hub_probe(struct platform_device *pdev) { + struct device_node *child = NULL; struct tegra_display_hub *hub; + struct clk *clk; unsigned int i; int err; @@ -801,6 +803,34 @@ static int tegra_display_hub_probe(struct platform_device *pdev) return err; } + hub->num_heads = of_get_child_count(pdev->dev.of_node); + + hub->clk_heads = devm_kcalloc(&pdev->dev, hub->num_heads, sizeof(clk), + GFP_KERNEL); + if (!hub->clk_heads) + return -ENOMEM; + + for (i = 0; i < hub->num_heads; i++) { + child = of_get_next_child(pdev->dev.of_node, child); + if (!child) { + dev_err(&pdev->dev, "failed to find node for head %u\n", + i); + return -ENODEV; + } + + clk = devm_get_clk_from_child(&pdev->dev, child, "dc"); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get clock for head %u\n", + i); + of_node_put(child); + return PTR_ERR(clk); + } + + hub->clk_heads[i] = clk; + } + + of_node_put(child); + /* XXX: enable clock across reset? */ err = reset_control_assert(hub->rst); if (err < 0) @@ -840,12 +870,16 @@ static int tegra_display_hub_remove(struct platform_device *pdev) static int __maybe_unused tegra_display_hub_suspend(struct device *dev) { struct tegra_display_hub *hub = dev_get_drvdata(dev); + unsigned int i = hub->num_heads; int err; err = reset_control_assert(hub->rst); if (err < 0) return err; + while (i--) + clk_disable_unprepare(hub->clk_heads[i]); + clk_disable_unprepare(hub->clk_hub); clk_disable_unprepare(hub->clk_dsc); clk_disable_unprepare(hub->clk_disp); @@ -856,6 +890,7 @@ static int __maybe_unused tegra_display_hub_suspend(struct device *dev) static int __maybe_unused tegra_display_hub_resume(struct device *dev) { struct tegra_display_hub *hub = dev_get_drvdata(dev); + unsigned int i; int err; err = clk_prepare_enable(hub->clk_disp); @@ -870,13 +905,22 @@ static int __maybe_unused tegra_display_hub_resume(struct device *dev) if (err < 0) goto disable_dsc; + for (i = 0; i < hub->num_heads; i++) { + err = clk_prepare_enable(hub->clk_heads[i]); + if (err < 0) + goto disable_heads; + } + err = reset_control_deassert(hub->rst); if (err < 0) - goto disable_hub; + goto disable_heads; return 0; -disable_hub: +disable_heads: + while (i--) + clk_disable_unprepare(hub->clk_heads[i]); + clk_disable_unprepare(hub->clk_hub); disable_dsc: clk_disable_unprepare(hub->clk_dsc); |