On Mon, 24 Feb 2020, 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@xxxxxxxxxx> > --- > drivers/video/backlight/lp855x_bl.c | 20 ++++++++++++++++---- > 1 file changed, 16 insertions(+), 4 deletions(-) Applied, thanks. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
