From 9b99044afc125c9dc6f739272d8b6f945a066064 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Wed, 29 Jun 2016 10:17:51 +0100 Subject: [PATCH] drm/tegra: Prepare DPAUX for supporting generic PM domains To utilise the DPAUX on Tegra, the SOR power partition must be enabled. Now that Tegra supports the generic PM domain framework we manage the SOR power partition via this framework for DPAUX. However, the sequence for gating/ungating the SOR power partition requires that the DPAUX 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 DPAUX driver cannot request the same reset unless we mark the resets 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 DPAUX reset, do not request the reset in the DPAUX driver if the DPAUX device has a PM domain associated. Signed-off-by: Jon Hunter Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/dpaux.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/tegra/dpaux.c b/drivers/gpu/drm/tegra/dpaux.c index b0b1f84e98b1..9575114cf719 100644 --- a/drivers/gpu/drm/tegra/dpaux.c +++ b/drivers/gpu/drm/tegra/dpaux.c @@ -341,11 +341,14 @@ static int tegra_dpaux_probe(struct platform_device *pdev) return -ENXIO; } - dpaux->rst = devm_reset_control_get(&pdev->dev, "dpaux"); - if (IS_ERR(dpaux->rst)) { - dev_err(&pdev->dev, "failed to get reset control: %ld\n", - PTR_ERR(dpaux->rst)); - return PTR_ERR(dpaux->rst); + if (!pdev->dev.pm_domain) { + dpaux->rst = devm_reset_control_get(&pdev->dev, "dpaux"); + if (IS_ERR(dpaux->rst)) { + dev_err(&pdev->dev, + "failed to get reset control: %ld\n", + PTR_ERR(dpaux->rst)); + return PTR_ERR(dpaux->rst); + } } dpaux->clk = devm_clk_get(&pdev->dev, NULL); @@ -362,7 +365,8 @@ static int tegra_dpaux_probe(struct platform_device *pdev) return err; } - reset_control_deassert(dpaux->rst); + if (dpaux->rst) + reset_control_deassert(dpaux->rst); dpaux->clk_parent = devm_clk_get(&pdev->dev, "parent"); if (IS_ERR(dpaux->clk_parent)) { @@ -440,7 +444,9 @@ static int tegra_dpaux_probe(struct platform_device *pdev) disable_parent_clk: clk_disable_unprepare(dpaux->clk_parent); assert_reset: - reset_control_assert(dpaux->rst); + if (dpaux->rst) + reset_control_assert(dpaux->rst); + clk_disable_unprepare(dpaux->clk); return err; @@ -462,7 +468,10 @@ static int tegra_dpaux_remove(struct platform_device *pdev) cancel_work_sync(&dpaux->work); clk_disable_unprepare(dpaux->clk_parent); - reset_control_assert(dpaux->rst); + + if (dpaux->rst) + reset_control_assert(dpaux->rst); + clk_disable_unprepare(dpaux->clk); return 0; -- 2.39.5