From f8c79120aa1d9eedb36cdadbd23489056a9f7b90 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Fri, 1 Jul 2016 14:21:38 +0100 Subject: [PATCH] drm/tegra: sor: Prepare for generic PM domain support The SOR driver for Tegra requires the SOR power partition to be enabled. Now that Tegra supports the generic PM domain framework we manage the SOR power partition via this framework. However, the sequence for gating/ungating the SOR power partition requires that the SOR reset is asserted/de-asserted at the time the SOR power partition is gated/ungated, respectively. Now that the reset control core assumes that resets are exclusive, the Tegra generic PM domain code and the SOR driver cannot request the same reset unless we mark the reset as shared. Sharing resets will not work in this case because we cannot guarantee that the reset will be asserted/de-asserted at the appropriate time. Therefore, given that the Tegra generic PM domain code will handle the resets, do not request the reset in the SOR driver if the SOR device has a PM domain associated. Signed-off-by: Jon Hunter Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/sor.c | 57 +++++++++++++++++++++++-------------- 1 file changed, 35 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c index b652201eadad..cb7e06062174 100644 --- a/drivers/gpu/drm/tegra/sor.c +++ b/drivers/gpu/drm/tegra/sor.c @@ -2350,10 +2350,13 @@ static int tegra_sor_init(struct host1x_client *client) * XXX: Remove this reset once proper hand-over from firmware to * kernel is possible. */ - err = reset_control_assert(sor->rst); - if (err < 0) { - dev_err(sor->dev, "failed to assert SOR reset: %d\n", err); - return err; + if (sor->rst) { + err = reset_control_assert(sor->rst); + if (err < 0) { + dev_err(sor->dev, "failed to assert SOR reset: %d\n", + err); + return err; + } } err = clk_prepare_enable(sor->clk); @@ -2364,10 +2367,13 @@ static int tegra_sor_init(struct host1x_client *client) usleep_range(1000, 3000); - err = reset_control_deassert(sor->rst); - if (err < 0) { - dev_err(sor->dev, "failed to deassert SOR reset: %d\n", err); - return err; + if (sor->rst) { + err = reset_control_deassert(sor->rst); + if (err < 0) { + dev_err(sor->dev, "failed to deassert SOR reset: %d\n", + err); + return err; + } } err = clk_prepare_enable(sor->clk_safe); @@ -2601,11 +2607,14 @@ static int tegra_sor_probe(struct platform_device *pdev) goto remove; } - sor->rst = devm_reset_control_get(&pdev->dev, "sor"); - if (IS_ERR(sor->rst)) { - err = PTR_ERR(sor->rst); - dev_err(&pdev->dev, "failed to get reset control: %d\n", err); - goto remove; + if (!pdev->dev.pm_domain) { + sor->rst = devm_reset_control_get(&pdev->dev, "sor"); + if (IS_ERR(sor->rst)) { + err = PTR_ERR(sor->rst); + dev_err(&pdev->dev, "failed to get reset control: %d\n", + err); + goto remove; + } } sor->clk = devm_clk_get(&pdev->dev, NULL); @@ -2711,10 +2720,12 @@ static int tegra_sor_suspend(struct device *dev) struct tegra_sor *sor = dev_get_drvdata(dev); int err; - err = reset_control_assert(sor->rst); - if (err < 0) { - dev_err(dev, "failed to assert reset: %d\n", err); - return err; + if (sor->rst) { + err = reset_control_assert(sor->rst); + if (err < 0) { + dev_err(dev, "failed to assert reset: %d\n", err); + return err; + } } usleep_range(1000, 2000); @@ -2737,11 +2748,13 @@ static int tegra_sor_resume(struct device *dev) usleep_range(1000, 2000); - err = reset_control_deassert(sor->rst); - if (err < 0) { - dev_err(dev, "failed to deassert reset: %d\n", err); - clk_disable_unprepare(sor->clk); - return err; + if (sor->rst) { + err = reset_control_deassert(sor->rst); + if (err < 0) { + dev_err(dev, "failed to deassert reset: %d\n", err); + clk_disable_unprepare(sor->clk); + return err; + } } return 0; -- 2.30.2