From 44419ce7d77e03692ed8fe799688d8dc43f9266e Mon Sep 17 00:00:00 2001 From: Emil Renner Berthing Date: Wed, 4 Oct 2017 19:53:46 +0200 Subject: [PATCH] drm/rockchip: analogix_dp: Use mutex rather than spinlock On the Samsung Chromebook Plus I get this error with 4.14-rc3: BUG: scheduling while atomic: kworker/3:1/50/0x00000002 Modules linked in: CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 4.14.0-0.rc3-kevin #2 Hardware name: Google Kevin (DT) Workqueue: events analogix_dp_psr_work Call trace: [] dump_backtrace+0x0/0x320 [] show_stack+0x14/0x20 [] dump_stack+0x9c/0xbc [] __schedule_bug+0x4c/0x70 [] __schedule+0x3f0/0x458 [] schedule+0x38/0xa0 [] schedule_hrtimeout_range_clock+0x84/0xe8 [] schedule_hrtimeout_range+0x10/0x18 [] usleep_range+0x64/0x78 [] analogix_dp_transfer+0x16c/0x340 [] analogix_dpaux_transfer+0x10/0x18 [] drm_dp_dpcd_access+0x4c/0xf0 [] drm_dp_dpcd_write+0x1c/0x28 [] analogix_dp_disable_psr+0x60/0xa8 [] analogix_dp_psr_work+0x4c/0x90 [] process_one_work+0x1d4/0x348 [] worker_thread+0x48/0x478 [] kthread+0x12c/0x130 [] ret_from_fork+0x10/0x18 Changing rockchip_dp_device::psr_lock to a mutex rather than spinlock seems to fix the issue. Signed-off-by: Emil Renner Berthing Tested-by: Enric Balletbo i Serra Signed-off-by: Mark Yao Link: https://patchwork.freedesktop.org/patch/msgid/20171004175346.11956-1-kernel@esmil.dk --- drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c index 9606121fa185..d8f72d87ef08 100644 --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c @@ -72,7 +72,7 @@ struct rockchip_dp_device { struct reset_control *rst; struct work_struct psr_work; - spinlock_t psr_lock; + struct mutex psr_lock; unsigned int psr_state; const struct rockchip_dp_chip_data *data; @@ -83,21 +83,20 @@ struct rockchip_dp_device { static void analogix_dp_psr_set(struct drm_encoder *encoder, bool enabled) { struct rockchip_dp_device *dp = to_dp(encoder); - unsigned long flags; if (!analogix_dp_psr_supported(dp->dev)) return; dev_dbg(dp->dev, "%s PSR...\n", enabled ? "Entry" : "Exit"); - spin_lock_irqsave(&dp->psr_lock, flags); + mutex_lock(&dp->psr_lock); if (enabled) dp->psr_state = EDP_VSC_PSR_STATE_ACTIVE; else dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE; schedule_work(&dp->psr_work); - spin_unlock_irqrestore(&dp->psr_lock, flags); + mutex_unlock(&dp->psr_lock); } static void analogix_dp_psr_work(struct work_struct *work) @@ -105,7 +104,6 @@ static void analogix_dp_psr_work(struct work_struct *work) struct rockchip_dp_device *dp = container_of(work, typeof(*dp), psr_work); int ret; - unsigned long flags; ret = rockchip_drm_wait_vact_end(dp->encoder.crtc, PSR_WAIT_LINE_FLAG_TIMEOUT_MS); @@ -114,12 +112,12 @@ static void analogix_dp_psr_work(struct work_struct *work) return; } - spin_lock_irqsave(&dp->psr_lock, flags); + mutex_lock(&dp->psr_lock); if (dp->psr_state == EDP_VSC_PSR_STATE_ACTIVE) analogix_dp_enable_psr(dp->dev); else analogix_dp_disable_psr(dp->dev); - spin_unlock_irqrestore(&dp->psr_lock, flags); + mutex_unlock(&dp->psr_lock); } static int rockchip_dp_pre_init(struct rockchip_dp_device *dp) @@ -381,7 +379,7 @@ static int rockchip_dp_bind(struct device *dev, struct device *master, dp->plat_data.power_off = rockchip_dp_powerdown; dp->plat_data.get_modes = rockchip_dp_get_modes; - spin_lock_init(&dp->psr_lock); + mutex_init(&dp->psr_lock); dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE; INIT_WORK(&dp->psr_work, analogix_dp_psr_work); -- 2.30.2