diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c index f6f0d0fa5ab286513b8663ce452f3969f6fe7188..20f154dda9cf37b1fed619b587c9fb49fccaaf75 100644 --- a/drivers/gpu/drm/msm/msm_mdss.c +++ b/drivers/gpu/drm/msm/msm_mdss.c @@ -4,11 +4,13 @@ */ #include <linux/clk.h> +#include <linux/delay.h> #include <linux/irq.h> #include <linux/irqchip.h> #include <linux/irqdesc.h> #include <linux/irqchip/chained_irq.h> #include <linux/pm_runtime.h> +#include <linux/reset.h> #include "msm_drv.h" #include "msm_kms.h" @@ -193,6 +195,32 @@ static void msm_mdss_destroy(struct msm_mdss *msm_mdss) irq_set_chained_handler_and_data(irq, NULL, NULL); } +static int msm_mdss_reset(struct device *dev) +{ + struct reset_control *reset; + + reset = reset_control_get_optional_exclusive(dev, NULL); + if (!reset) { + /* Optional reset not specified */ + return 0; + } else if (IS_ERR(reset)) { + return dev_err_probe(dev, PTR_ERR(reset), + "failed to acquire mdss reset\n"); + } + + reset_control_assert(reset); + /* + * Tests indicate that reset has to be held for some period of time, + * make it one frame in a typical system + */ + msleep(20); + reset_control_deassert(reset); + + reset_control_put(reset); + + return 0; +} + /* * MDP5 MDSS uses at most three specified clocks. */ @@ -229,6 +257,10 @@ static struct msm_mdss *msm_mdss_init(struct platform_device *pdev, bool is_mdp5 int ret; int irq; + ret = msm_mdss_reset(&pdev->dev); + if (ret) + return ERR_PTR(ret); + msm_mdss = devm_kzalloc(&pdev->dev, sizeof(*msm_mdss), GFP_KERNEL); if (!msm_mdss) return ERR_PTR(-ENOMEM);