From 64230aa075864f7c8e270b583bca685304246b57 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Fri, 1 Jul 2016 14:21:37 +0100 Subject: [PATCH] drm/tegra: dsi: Prepare for generic PM domain support The DSI 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 DSI 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 DSI 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 DSI driver if the DSI device has a PM domain associated. Signed-off-by: Jon Hunter Signed-off-by: Thierry Reding --- drivers/gpu/drm/tegra/dsi.c | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c index 7e75215..972618e 100644 --- a/drivers/gpu/drm/tegra/dsi.c +++ b/drivers/gpu/drm/tegra/dsi.c @@ -1489,9 +1489,11 @@ static int tegra_dsi_probe(struct platform_device *pdev) dsi->format = MIPI_DSI_FMT_RGB888; dsi->lanes = 4; - dsi->rst = devm_reset_control_get(&pdev->dev, "dsi"); - if (IS_ERR(dsi->rst)) - return PTR_ERR(dsi->rst); + if (!pdev->dev.pm_domain) { + dsi->rst = devm_reset_control_get(&pdev->dev, "dsi"); + if (IS_ERR(dsi->rst)) + return PTR_ERR(dsi->rst); + } dsi->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(dsi->clk)) { @@ -1592,10 +1594,12 @@ static int tegra_dsi_suspend(struct device *dev) struct tegra_dsi *dsi = dev_get_drvdata(dev); int err; - err = reset_control_assert(dsi->rst); - if (err < 0) { - dev_err(dev, "failed to assert reset: %d\n", err); - return err; + if (dsi->rst) { + err = reset_control_assert(dsi->rst); + if (err < 0) { + dev_err(dev, "failed to assert reset: %d\n", err); + return err; + } } usleep_range(1000, 2000); @@ -1633,10 +1637,12 @@ static int tegra_dsi_resume(struct device *dev) usleep_range(1000, 2000); - err = reset_control_deassert(dsi->rst); - if (err < 0) { - dev_err(dev, "cannot assert reset: %d\n", err); - goto disable_clk_lp; + if (dsi->rst) { + err = reset_control_deassert(dsi->rst); + if (err < 0) { + dev_err(dev, "cannot assert reset: %d\n", err); + goto disable_clk_lp; + } } return 0; -- 2.7.4