forge/linux-uconsole
1
0
Fork 0
Code Issues 1 Pull requests Projects Releases Packages Wiki Activity Actions

backlight: lp855x: Ensure regulators are disabled on probe failure

Browse source 
[ Upstream commit d8207c155a ]

If probing the LP885x backlight fails after the regulators have been
enabled, then the following warning is seen when releasing the
regulators ...

 WARNING: CPU: 1 PID: 289 at drivers/regulator/core.c:2051 _regulator_put.part.28+0x158/0x160
 Modules linked in: tegra_xudc lp855x_bl(+) host1x pwm_tegra ip_tables x_tables ipv6 nf_defrag_ipv6
 CPU: 1 PID: 289 Comm: systemd-udevd Not tainted 5.6.0-rc2-next-20200224 #1
 Hardware name: NVIDIA Jetson TX1 Developer Kit (DT)

 ...

 Call trace:
  _regulator_put.part.28+0x158/0x160
  regulator_put+0x34/0x50
  devm_regulator_release+0x10/0x18
  release_nodes+0x12c/0x230
  devres_release_all+0x34/0x50
  really_probe+0x1c0/0x370
  driver_probe_device+0x58/0x100
  device_driver_attach+0x6c/0x78
  __driver_attach+0xb0/0xf0
  bus_for_each_dev+0x68/0xc8
  driver_attach+0x20/0x28
  bus_add_driver+0x160/0x1f0
  driver_register+0x60/0x110
  i2c_register_driver+0x40/0x80
  lp855x_driver_init+0x20/0x1000 [lp855x_bl]
  do_one_initcall+0x58/0x1a0
  do_init_module+0x54/0x1d0
  load_module+0x1d80/0x21c8
  __do_sys_finit_module+0xe8/0x100
  __arm64_sys_finit_module+0x18/0x20
  el0_svc_common.constprop.3+0xb0/0x168
  do_el0_svc+0x20/0x98
  el0_sync_handler+0xf4/0x1b0
  el0_sync+0x140/0x180

Fix this by ensuring that the regulators are disabled, if enabled, on
probe failure.

Finally, ensure that the vddio regulator is disabled in the driver
remove handler.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jon Hunter 2020-02-24 14:07:48 +00:00 • committed by Greg Kroah-Hartman
commit 5970f0c994
1 changed files with 16 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

20
drivers/video/backlight/lp855x_bl.c
View file

@ -460,7 +460,7 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
ret = regulator_enable(lp->enable);
if (ret < 0) {
dev_err(lp->dev, "failed to enable vddio: %d\n", ret);
return ret;
goto disable_supply;
}
/*
@ -475,24 +475,34 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
ret = lp855x_configure(lp);
if (ret) {
dev_err(lp->dev, "device config err: %d", ret);
return ret;
goto disable_vddio;
}
ret = lp855x_backlight_register(lp);
if (ret) {
dev_err(lp->dev,
"failed to register backlight. err: %d\n", ret);
return ret;
goto disable_vddio;
}
ret = sysfs_create_group(&lp->dev->kobj, &lp855x_attr_group);
if (ret) {
dev_err(lp->dev, "failed to register sysfs. err: %d\n", ret);
return ret;
goto disable_vddio;
}
backlight_update_status(lp->bl);
return 0;
disable_vddio:
if (lp->enable)
regulator_disable(lp->enable);
disable_supply:
if (lp->supply)
regulator_disable(lp->supply);
return ret;
}
static int lp855x_remove(struct i2c_client *cl)
@ -501,6 +511,8 @@ static int lp855x_remove(struct i2c_client *cl)
lp->bl->props.brightness = 0;
backlight_update_status(lp->bl);
if (lp->enable)
regulator_disable(lp->enable);
if (lp->supply)
regulator_disable(lp->supply);
sysfs_remove_group(&lp->dev->kobj, &lp855x_attr_group);