On 01/05/2017 01:01 PM, Sean Paul wrote: > On Fri, Dec 30, 2016 at 4:57 AM, Marek Szyprowski > <m.szyprowski at samsung.com> wrote: >> 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.
Pushed to drm-misc-fixes. Thanks, Archit >> >> 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 ]--- >> > > Reviewed-by: Sean Paul <seanpaul at chromium.org> > >> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com> >> --- >> 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 >> > > > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
