Analogix_dp_bind() can be called from component framework, which doesn't guarantee proper runtime PM state of the device during bind operation, so ensure that device is runtime active before doing any register access. This ensures that the power domain, to which DP module belongs, is turned on. While at it, also fix the unbalanced call to phy_power_on() in analogix_dp_bind() function. This patch solves the following kernel oops on Samsung Exynos5250 Snow board: Unhandled fault: imprecise external abort (0x406) at 0x00000000 pgd = c0004000 [00000000] *pgd=00000000 Internal error: : 406 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 75 Comm: kworker/0:2 Not tainted 4.9.0 #1046 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) Workqueue: events deferred_probe_work_func task: ee272300 task.stack: ee312000 PC is at analogix_dp_enable_sw_function+0x18/0x2c LR is at analogix_dp_init_dp+0x2c/0x50 ... [<c03fcb38>] (analogix_dp_enable_sw_function) from [<c03fa9c4>] (analogix_dp_init_dp+0x2c/0x50) [<c03fa9c4>] (analogix_dp_init_dp) from [<c03fab6c>] (analogix_dp_bind+0x184/0x42c) [<c03fab6c>] (analogix_dp_bind) from [<c03fdb84>] (component_bind_all+0xf0/0x218) [<c03fdb84>] (component_bind_all) from [<c03ed64c>] (exynos_drm_load+0x134/0x200) [<c03ed64c>] (exynos_drm_load) from [<c03d5058>] (drm_dev_register+0xa0/0xd0) [<c03d5058>] (drm_dev_register) from [<c03d66b8>] (drm_platform_init+0x58/0xb0) [<c03d66b8>] (drm_platform_init) from [<c03fe0c4>] (try_to_bring_up_master+0x14c/0x188) [<c03fe0c4>] (try_to_bring_up_master) from [<c03fe188>] (component_add+0x88/0x138) [<c03fe188>] (component_add) from [<c0403a38>] (platform_drv_probe+0x50/0xb0) [<c0403a38>] (platform_drv_probe) from [<c0402470>] (driver_probe_device+0x1f0/0x2a8) [<c0402470>] (driver_probe_device) from [<c0400a54>] (bus_for_each_drv+0x44/0x8c) [<c0400a54>] (bus_for_each_drv) from [<c04021f8>] (__device_attach+0x9c/0x100) [<c04021f8>] (__device_attach) from [<c04018e8>] (bus_probe_device+0x84/0x8c) [<c04018e8>] (bus_probe_device) from [<c0401d1c>] (deferred_probe_work_func+0x60/0x8c) [<c0401d1c>] (deferred_probe_work_func) from [<c012fc14>] (process_one_work+0x120/0x318) [<c012fc14>] (process_one_work) from [<c012fe34>] (process_scheduled_works+0x28/0x38) [<c012fe34>] (process_scheduled_works) from [<c0130048>] (worker_thread+0x204/0x4ac) [<c0130048>] (worker_thread) from [<c01352c4>] (kthread+0xd8/0xf4) [<c01352c4>] (kthread) from [<c0107978>] (ret_from_fork+0x14/0x3c) Code: e59035f0 e5935018 f57ff04f e3c55001 (f57ff04e) ---[ end trace 3d1d0d87796de344 ]--- Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> --- drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c index eb9bf8786c24..18eefdcbf1ba 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c @@ -1382,6 +1382,7 @@ int analogix_dp_bind(struct device *dev, struct drm_device *drm_dev, pm_runtime_enable(dev); + pm_runtime_get_sync(dev); phy_power_on(dp->phy); analogix_dp_init_dp(dp); @@ -1414,9 +1415,15 @@ int analogix_dp_bind(struct device *dev, struct drm_device *drm_dev, goto err_disable_pm_runtime; } + phy_power_off(dp->phy); + pm_runtime_put(dev); + return 0; err_disable_pm_runtime: + + phy_power_off(dp->phy); + pm_runtime_put(dev); pm_runtime_disable(dev); return ret; -- 1.9.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
