diff options
Diffstat (limited to '0001-backlight-lp855x-Ensure-regulators-are-disabled-on-p.patch')
| -rw-r--r-- | 0001-backlight-lp855x-Ensure-regulators-are-disabled-on-p.patch | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/0001-backlight-lp855x-Ensure-regulators-are-disabled-on-p.patch b/0001-backlight-lp855x-Ensure-regulators-are-disabled-on-p.patch new file mode 100644 index 000000000..c6fdb5aa6 --- /dev/null +++ b/0001-backlight-lp855x-Ensure-regulators-are-disabled-on-p.patch @@ -0,0 +1,118 @@ +From 9b408dc1e89cfe36a8f715a7c7624687bb876028 Mon Sep 17 00:00:00 2001 +From: Jon Hunter <jonathanh@nvidia.com> +Date: Mon, 24 Feb 2020 14:07:48 +0000 +Subject: [PATCH] backlight: lp855x: Ensure regulators are disabled on probe + failure + +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> +--- + drivers/video/backlight/lp855x_bl.c | 20 ++++++++++++++++---- + 1 file changed, 16 insertions(+), 4 deletions(-) + +diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c +index f68920131a4a..e94932c69f54 100644 +--- a/drivers/video/backlight/lp855x_bl.c ++++ b/drivers/video/backlight/lp855x_bl.c +@@ -456,7 +456,7 @@ 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; + } + + /* +@@ -471,24 +471,34 @@ 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) +@@ -497,6 +507,8 @@ 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); +-- +2.26.0 + |