Hi Lee, Daniel,
On 24/02/2020 14:37, Daniel Thompson wrote:
On Mon, Feb 24, 2020 at 02:07:48PM +0000, Jon Hunter wrote:
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
I received a bounce from Milo's email and so I am not sure that his email address is still valid.
Can either of you pick this up?
Not sure if we should update the MAINTAINERS as well?
Jon