From: Lee Jones <lee.jones@linaro.org>
To: Chen-Yu Tsai <wens@csie.org>
Cc: linux-pwm@vger.kernel.org,
Daniel Thompson <daniel.thompson@linaro.org>,
Maxime Ripard <maxime.ripard@bootlin.com>,
Jingoo Han <jingoohan1@gmail.com>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
Thierry Reding <thierry.reding@gmail.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state
Date: Wed, 30 Jan 2019 13:36:05 +0000 [thread overview]
Message-ID: <20190130133605.GI4701@dell> (raw)
In-Reply-To: <20190127145054.3770-1-wens@csie.org>
On Sun, 27 Jan 2019, Chen-Yu Tsai wrote:
> gpiod_get_value() gives out a warning if access to the underlying gpiochip
> requires sleeping, which is common for I2C based chips:
>
> WARNING: CPU: 0 PID: 77 at drivers/gpio/gpiolib.c:2500 gpiod_get_value+0xd0/0x100
> Modules linked in:
> CPU: 0 PID: 77 Comm: kworker/0:2 Not tainted 4.14.0-rc3-00589-gf32897915d48-dirty #90
> Hardware name: Allwinner sun4i/sun5i Families
> Workqueue: events deferred_probe_work_func
> [<c010ec50>] (unwind_backtrace) from [<c010b784>] (show_stack+0x10/0x14)
> [<c010b784>] (show_stack) from [<c0797224>] (dump_stack+0x88/0x9c)
> [<c0797224>] (dump_stack) from [<c0125b08>] (__warn+0xe8/0x100)
> [<c0125b08>] (__warn) from [<c0125bd0>] (warn_slowpath_null+0x20/0x28)
> [<c0125bd0>] (warn_slowpath_null) from [<c037069c>] (gpiod_get_value+0xd0/0x100)
> [<c037069c>] (gpiod_get_value) from [<c03778d0>] (pwm_backlight_probe+0x238/0x508)
> [<c03778d0>] (pwm_backlight_probe) from [<c0411a2c>] (platform_drv_probe+0x50/0xac)
> [<c0411a2c>] (platform_drv_probe) from [<c0410224>] (driver_probe_device+0x238/0x2e8)
> [<c0410224>] (driver_probe_device) from [<c040e820>] (bus_for_each_drv+0x44/0x94)
> [<c040e820>] (bus_for_each_drv) from [<c040ff0c>] (__device_attach+0xb0/0x114)
> [<c040ff0c>] (__device_attach) from [<c040f4f8>] (bus_probe_device+0x84/0x8c)
> [<c040f4f8>] (bus_probe_device) from [<c040f944>] (deferred_probe_work_func+0x50/0x14c)
> [<c040f944>] (deferred_probe_work_func) from [<c013be84>] (process_one_work+0x1ec/0x414)
> [<c013be84>] (process_one_work) from [<c013ce5c>] (worker_thread+0x2b0/0x5a0)
> [<c013ce5c>] (worker_thread) from [<c0141908>] (kthread+0x14c/0x154)
> [<c0141908>] (kthread) from [<c0107ab0>] (ret_from_fork+0x14/0x24)
>
> This was missed in commit 0c9501f823a4 ("backlight: pwm_bl: Handle gpio
> that can sleep"). The code was then moved to a separate function in
> commit 7613c922315e ("backlight: pwm_bl: Move the checks for initial power
> state to a separate function").
>
> The only usage of gpiod_get_value() is during the probe stage, which is
> safe to sleep in. Switch to gpiod_get_value_cansleep().
>
> Fixes: 0c9501f823a4 ("backlight: pwm_bl: Handle gpio that can sleep")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
> drivers/video/backlight/pwm_bl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Applied, thanks.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
WARNING: multiple messages have this Message-ID (diff)
From: Lee Jones <lee.jones@linaro.org>
To: Chen-Yu Tsai <wens@csie.org>
Cc: linux-pwm@vger.kernel.org,
Daniel Thompson <daniel.thompson@linaro.org>,
Maxime Ripard <maxime.ripard@bootlin.com>,
Jingoo Han <jingoohan1@gmail.com>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
Thierry Reding <thierry.reding@gmail.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state
Date: Wed, 30 Jan 2019 13:36:05 +0000 [thread overview]
Message-ID: <20190130133605.GI4701@dell> (raw)
In-Reply-To: <20190127145054.3770-1-wens@csie.org>
On Sun, 27 Jan 2019, Chen-Yu Tsai wrote:
> gpiod_get_value() gives out a warning if access to the underlying gpiochip
> requires sleeping, which is common for I2C based chips:
>
> WARNING: CPU: 0 PID: 77 at drivers/gpio/gpiolib.c:2500 gpiod_get_value+0xd0/0x100
> Modules linked in:
> CPU: 0 PID: 77 Comm: kworker/0:2 Not tainted 4.14.0-rc3-00589-gf32897915d48-dirty #90
> Hardware name: Allwinner sun4i/sun5i Families
> Workqueue: events deferred_probe_work_func
> [<c010ec50>] (unwind_backtrace) from [<c010b784>] (show_stack+0x10/0x14)
> [<c010b784>] (show_stack) from [<c0797224>] (dump_stack+0x88/0x9c)
> [<c0797224>] (dump_stack) from [<c0125b08>] (__warn+0xe8/0x100)
> [<c0125b08>] (__warn) from [<c0125bd0>] (warn_slowpath_null+0x20/0x28)
> [<c0125bd0>] (warn_slowpath_null) from [<c037069c>] (gpiod_get_value+0xd0/0x100)
> [<c037069c>] (gpiod_get_value) from [<c03778d0>] (pwm_backlight_probe+0x238/0x508)
> [<c03778d0>] (pwm_backlight_probe) from [<c0411a2c>] (platform_drv_probe+0x50/0xac)
> [<c0411a2c>] (platform_drv_probe) from [<c0410224>] (driver_probe_device+0x238/0x2e8)
> [<c0410224>] (driver_probe_device) from [<c040e820>] (bus_for_each_drv+0x44/0x94)
> [<c040e820>] (bus_for_each_drv) from [<c040ff0c>] (__device_attach+0xb0/0x114)
> [<c040ff0c>] (__device_attach) from [<c040f4f8>] (bus_probe_device+0x84/0x8c)
> [<c040f4f8>] (bus_probe_device) from [<c040f944>] (deferred_probe_work_func+0x50/0x14c)
> [<c040f944>] (deferred_probe_work_func) from [<c013be84>] (process_one_work+0x1ec/0x414)
> [<c013be84>] (process_one_work) from [<c013ce5c>] (worker_thread+0x2b0/0x5a0)
> [<c013ce5c>] (worker_thread) from [<c0141908>] (kthread+0x14c/0x154)
> [<c0141908>] (kthread) from [<c0107ab0>] (ret_from_fork+0x14/0x24)
>
> This was missed in commit 0c9501f823a4 ("backlight: pwm_bl: Handle gpio
> that can sleep"). The code was then moved to a separate function in
> commit 7613c922315e ("backlight: pwm_bl: Move the checks for initial power
> state to a separate function").
>
> The only usage of gpiod_get_value() is during the probe stage, which is
> safe to sleep in. Switch to gpiod_get_value_cansleep().
>
> Fixes: 0c9501f823a4 ("backlight: pwm_bl: Handle gpio that can sleep")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
> drivers/video/backlight/pwm_bl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Applied, thanks.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
WARNING: multiple messages have this Message-ID (diff)
From: Lee Jones <lee.jones@linaro.org>
To: Chen-Yu Tsai <wens@csie.org>
Cc: Thierry Reding <thierry.reding@gmail.com>,
Daniel Thompson <daniel.thompson@linaro.org>,
Jingoo Han <jingoohan1@gmail.com>,
linux-pwm@vger.kernel.org, dri-devel@lists.freedesktop.org,
linux-kernel@vger.kernel.org,
Maxime Ripard <maxime.ripard@bootlin.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state
Date: Wed, 30 Jan 2019 13:36:05 +0000 [thread overview]
Message-ID: <20190130133605.GI4701@dell> (raw)
In-Reply-To: <20190127145054.3770-1-wens@csie.org>
On Sun, 27 Jan 2019, Chen-Yu Tsai wrote:
> gpiod_get_value() gives out a warning if access to the underlying gpiochip
> requires sleeping, which is common for I2C based chips:
>
> WARNING: CPU: 0 PID: 77 at drivers/gpio/gpiolib.c:2500 gpiod_get_value+0xd0/0x100
> Modules linked in:
> CPU: 0 PID: 77 Comm: kworker/0:2 Not tainted 4.14.0-rc3-00589-gf32897915d48-dirty #90
> Hardware name: Allwinner sun4i/sun5i Families
> Workqueue: events deferred_probe_work_func
> [<c010ec50>] (unwind_backtrace) from [<c010b784>] (show_stack+0x10/0x14)
> [<c010b784>] (show_stack) from [<c0797224>] (dump_stack+0x88/0x9c)
> [<c0797224>] (dump_stack) from [<c0125b08>] (__warn+0xe8/0x100)
> [<c0125b08>] (__warn) from [<c0125bd0>] (warn_slowpath_null+0x20/0x28)
> [<c0125bd0>] (warn_slowpath_null) from [<c037069c>] (gpiod_get_value+0xd0/0x100)
> [<c037069c>] (gpiod_get_value) from [<c03778d0>] (pwm_backlight_probe+0x238/0x508)
> [<c03778d0>] (pwm_backlight_probe) from [<c0411a2c>] (platform_drv_probe+0x50/0xac)
> [<c0411a2c>] (platform_drv_probe) from [<c0410224>] (driver_probe_device+0x238/0x2e8)
> [<c0410224>] (driver_probe_device) from [<c040e820>] (bus_for_each_drv+0x44/0x94)
> [<c040e820>] (bus_for_each_drv) from [<c040ff0c>] (__device_attach+0xb0/0x114)
> [<c040ff0c>] (__device_attach) from [<c040f4f8>] (bus_probe_device+0x84/0x8c)
> [<c040f4f8>] (bus_probe_device) from [<c040f944>] (deferred_probe_work_func+0x50/0x14c)
> [<c040f944>] (deferred_probe_work_func) from [<c013be84>] (process_one_work+0x1ec/0x414)
> [<c013be84>] (process_one_work) from [<c013ce5c>] (worker_thread+0x2b0/0x5a0)
> [<c013ce5c>] (worker_thread) from [<c0141908>] (kthread+0x14c/0x154)
> [<c0141908>] (kthread) from [<c0107ab0>] (ret_from_fork+0x14/0x24)
>
> This was missed in commit 0c9501f823a4 ("backlight: pwm_bl: Handle gpio
> that can sleep"). The code was then moved to a separate function in
> commit 7613c922315e ("backlight: pwm_bl: Move the checks for initial power
> state to a separate function").
>
> The only usage of gpiod_get_value() is during the probe stage, which is
> safe to sleep in. Switch to gpiod_get_value_cansleep().
>
> Fixes: 0c9501f823a4 ("backlight: pwm_bl: Handle gpio that can sleep")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> ---
> drivers/video/backlight/pwm_bl.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Applied, thanks.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
next prev parent reply other threads:[~2019-01-30 13:36 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-27 14:50 [PATCH] backlight: pwm_bl: Use gpiod_get_value_cansleep() to get initial state Chen-Yu Tsai
2019-01-27 14:50 ` Chen-Yu Tsai
2019-01-28 10:38 ` Maxime Ripard
2019-01-28 10:38 ` Maxime Ripard
2019-01-28 11:05 ` Daniel Thompson
2019-01-28 11:05 ` Daniel Thompson
2019-01-28 11:05 ` Daniel Thompson
2019-01-30 13:36 ` Lee Jones [this message]
2019-01-30 13:36 ` Lee Jones
2019-01-30 13:36 ` Lee Jones
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