[PATCH] Input: cyapa - add missing input core locking to suspend/resume functions

From: Marek Szyprowski
Date: Mon Oct 09 2023 - 08:10:35 EST


Grab input->mutex during suspend/resume functions like it is done in
other input drivers. This fixes the following warning during system
suspend/resume cycle on Samsung Exynos5250-based Snow Chromebook:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 1680 at drivers/input/input.c:2291 input_device_enabled+0x68/0x6c
Modules linked in: ...
CPU: 1 PID: 1680 Comm: kworker/u4:12 Tainted: G W 6.6.0-rc5-next-20231009 #14109
Hardware name: Samsung Exynos (Flattened Device Tree)
Workqueue: events_unbound async_run_entry_fn
unwind_backtrace from show_stack+0x10/0x14
show_stack from dump_stack_lvl+0x58/0x70
dump_stack_lvl from __warn+0x1a8/0x1cc
__warn from warn_slowpath_fmt+0x18c/0x1b4
warn_slowpath_fmt from input_device_enabled+0x68/0x6c
input_device_enabled from cyapa_gen3_set_power_mode+0x13c/0x1dc
cyapa_gen3_set_power_mode from cyapa_reinitialize+0x10c/0x15c
cyapa_reinitialize from cyapa_resume+0x48/0x98
cyapa_resume from dpm_run_callback+0x90/0x298
dpm_run_callback from device_resume+0xb4/0x258
device_resume from async_resume+0x20/0x64
async_resume from async_run_entry_fn+0x40/0x15c
async_run_entry_fn from process_scheduled_works+0xbc/0x6a8
process_scheduled_works from worker_thread+0x188/0x454
worker_thread from kthread+0x108/0x140
kthread from ret_from_fork+0x14/0x28
Exception stack(0xf1625fb0 to 0xf1625ff8)
...
---[ end trace 0000000000000000 ]---
...
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1680 at drivers/input/input.c:2291 input_device_enabled+0x68/0x6c
Modules linked in: ...
CPU: 1 PID: 1680 Comm: kworker/u4:12 Tainted: G W 6.6.0-rc5-next-20231009 #14109
Hardware name: Samsung Exynos (Flattened Device Tree)
Workqueue: events_unbound async_run_entry_fn
unwind_backtrace from show_stack+0x10/0x14
show_stack from dump_stack_lvl+0x58/0x70
dump_stack_lvl from __warn+0x1a8/0x1cc
__warn from warn_slowpath_fmt+0x18c/0x1b4
warn_slowpath_fmt from input_device_enabled+0x68/0x6c
input_device_enabled from cyapa_gen3_set_power_mode+0x13c/0x1dc
cyapa_gen3_set_power_mode from cyapa_reinitialize+0x10c/0x15c
cyapa_reinitialize from cyapa_resume+0x48/0x98
cyapa_resume from dpm_run_callback+0x90/0x298
dpm_run_callback from device_resume+0xb4/0x258
device_resume from async_resume+0x20/0x64
async_resume from async_run_entry_fn+0x40/0x15c
async_run_entry_fn from process_scheduled_works+0xbc/0x6a8
process_scheduled_works from worker_thread+0x188/0x454
worker_thread from kthread+0x108/0x140
kthread from ret_from_fork+0x14/0x28
Exception stack(0xf1625fb0 to 0xf1625ff8)
...
---[ end trace 0000000000000000 ]---

Fixes: d69f0a43c677 ("Input: use input_device_enabled()")
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
drivers/input/mouse/cyapa.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/input/mouse/cyapa.c b/drivers/input/mouse/cyapa.c
index a84098448f5b..cf23f95b5f11 100644
--- a/drivers/input/mouse/cyapa.c
+++ b/drivers/input/mouse/cyapa.c
@@ -1347,10 +1347,16 @@ static int cyapa_suspend(struct device *dev)
u8 power_mode;
int error;

- error = mutex_lock_interruptible(&cyapa->state_sync_lock);
+ error = mutex_lock_interruptible(&cyapa->input->mutex);
if (error)
return error;

+ error = mutex_lock_interruptible(&cyapa->state_sync_lock);
+ if (error) {
+ mutex_unlock(&cyapa->input->mutex);
+ return error;
+ }
+
/*
* Runtime PM is enable only when device is in operational mode and
* users in use, so need check it before disable it to
@@ -1385,6 +1391,8 @@ static int cyapa_suspend(struct device *dev)
cyapa->irq_wake = (enable_irq_wake(client->irq) == 0);

mutex_unlock(&cyapa->state_sync_lock);
+ mutex_unlock(&cyapa->input->mutex);
+
return 0;
}

@@ -1394,6 +1402,7 @@ static int cyapa_resume(struct device *dev)
struct cyapa *cyapa = i2c_get_clientdata(client);
int error;

+ mutex_lock(&cyapa->input->mutex);
mutex_lock(&cyapa->state_sync_lock);

if (device_may_wakeup(dev) && cyapa->irq_wake) {
@@ -1412,6 +1421,7 @@ static int cyapa_resume(struct device *dev)
enable_irq(client->irq);

mutex_unlock(&cyapa->state_sync_lock);
+ mutex_unlock(&cyapa->input->mutex);
return 0;
}

--
2.34.1