* [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
@ 2014-03-31 18:14 Stephen Boyd
2014-03-31 18:23 ` Dmitry Torokhov
2014-03-31 18:23 ` Josh Cartwright
0 siblings, 2 replies; 6+ messages in thread
From: Stephen Boyd @ 2014-03-31 18:14 UTC (permalink / raw)
To: Dmitry Torokhov
Cc: linux-kernel, linux-arm-msm, linux-arm-kernel, linux-input,
Arnd Bergmann
If the debounce time is 0 our usage of ilog2() later on in this
driver will cause undefined behavior. If CONFIG_OF=n this fact is
evident to the compiler, and it emits a call to ____ilog2_NaN()
which doesn't exist. Fix this by setting a sane default for
debounce.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
index 1cb8fda7a166..27add04676e1 100644
--- a/drivers/input/misc/pmic8xxx-pwrkey.c
+++ b/drivers/input/misc/pmic8xxx-pwrkey.c
@@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
bool pull_up;
if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
- kpd_delay = 0;
+ kpd_delay = 15625;
pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up");
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
hosted by The Linux Foundation
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
2014-03-31 18:14 [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time Stephen Boyd
@ 2014-03-31 18:23 ` Dmitry Torokhov
2014-03-31 18:29 ` Stephen Boyd
2014-03-31 18:23 ` Josh Cartwright
1 sibling, 1 reply; 6+ messages in thread
From: Dmitry Torokhov @ 2014-03-31 18:23 UTC (permalink / raw)
To: Stephen Boyd
Cc: linux-kernel, linux-arm-msm, linux-arm-kernel, linux-input,
Arnd Bergmann
On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote:
> If the debounce time is 0 our usage of ilog2() later on in this
> driver will cause undefined behavior. If CONFIG_OF=n this fact is
> evident to the compiler, and it emits a call to ____ilog2_NaN()
> which doesn't exist. Fix this by setting a sane default for
> debounce.
>
> Reported-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> ---
> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
> index 1cb8fda7a166..27add04676e1 100644
> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> bool pull_up;
>
> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
> - kpd_delay = 0;
> + kpd_delay = 15625;
What if somebody supplied 0 via DT? Can we check and return -EINVAL?
>
> pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up");
>
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
>
--
Dmitry
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
2014-03-31 18:14 [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time Stephen Boyd
2014-03-31 18:23 ` Dmitry Torokhov
@ 2014-03-31 18:23 ` Josh Cartwright
2014-03-31 18:48 ` Stephen Boyd
1 sibling, 1 reply; 6+ messages in thread
From: Josh Cartwright @ 2014-03-31 18:23 UTC (permalink / raw)
To: Stephen Boyd
Cc: Dmitry Torokhov, linux-kernel, linux-arm-msm, linux-arm-kernel,
linux-input, Arnd Bergmann
On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote:
> If the debounce time is 0 our usage of ilog2() later on in this
> driver will cause undefined behavior. If CONFIG_OF=n this fact is
> evident to the compiler, and it emits a call to ____ilog2_NaN()
> which doesn't exist. Fix this by setting a sane default for
> debounce.
>
> Reported-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> ---
> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
> index 1cb8fda7a166..27add04676e1 100644
> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> bool pull_up;
>
> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
> - kpd_delay = 0;
> + kpd_delay = 15625;
Should "debounce" even be optional? I'm wondering if we should just
make it required...
At the very least this default value should be documented in the DT
binding.
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
2014-03-31 18:23 ` Dmitry Torokhov
@ 2014-03-31 18:29 ` Stephen Boyd
2014-05-14 19:02 ` Dmitry Torokhov
0 siblings, 1 reply; 6+ messages in thread
From: Stephen Boyd @ 2014-03-31 18:29 UTC (permalink / raw)
To: Dmitry Torokhov
Cc: linux-kernel, linux-arm-msm, linux-arm-kernel, linux-input,
Arnd Bergmann
On 03/31/14 11:23, Dmitry Torokhov wrote:
> On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote:
>> If the debounce time is 0 our usage of ilog2() later on in this
>> driver will cause undefined behavior. If CONFIG_OF=n this fact is
>> evident to the compiler, and it emits a call to ____ilog2_NaN()
>> which doesn't exist. Fix this by setting a sane default for
>> debounce.
>>
>> Reported-by: Arnd Bergmann <arnd@arndb.de>
>> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
>> ---
>> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
>> index 1cb8fda7a166..27add04676e1 100644
>> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
>> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
>> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
>> bool pull_up;
>>
>> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
>> - kpd_delay = 0;
>> + kpd_delay = 15625;
> What if somebody supplied 0 via DT? Can we check and return -EINVAL?
Sure. Here's a v2.
-----8<------
From: Stephen Boyd <sboyd@codeaurora.org>
Subject: [PATCH v2] Input: pmic8xxx-pwrkey - Set sane default for debounce
time
If the debounce time is 0 our usage of ilog2() later on in this
driver will cause undefined behavior. If CONFIG_OF=n this fact is
evident to the compiler, and it emits a call to ____ilog2_NaN()
which doesn't exist. Fix this by setting a sane default for
debounce and failing to probe if debounce is 0 in the DT.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/input/misc/pmic8xxx-pwrkey.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
index 1cb8fda7a166..3fb161902cc6 100644
--- a/drivers/input/misc/pmic8xxx-pwrkey.c
+++ b/drivers/input/misc/pmic8xxx-pwrkey.c
@@ -92,11 +92,11 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
bool pull_up;
if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
- kpd_delay = 0;
+ kpd_delay = 15625;
pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up");
- if (kpd_delay > 62500) {
+ if (kpd_delay > 62500 || kpd_delay == 0) {
dev_err(&pdev->dev, "invalid power key trigger delay\n");
return -EINVAL;
}
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
2014-03-31 18:23 ` Josh Cartwright
@ 2014-03-31 18:48 ` Stephen Boyd
0 siblings, 0 replies; 6+ messages in thread
From: Stephen Boyd @ 2014-03-31 18:48 UTC (permalink / raw)
To: Josh Cartwright
Cc: Dmitry Torokhov, linux-kernel, linux-arm-msm, linux-arm-kernel,
linux-input, Arnd Bergmann
On 03/31/14 11:23, Josh Cartwright wrote:
> On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote:
>> If the debounce time is 0 our usage of ilog2() later on in this
>> driver will cause undefined behavior. If CONFIG_OF=n this fact is
>> evident to the compiler, and it emits a call to ____ilog2_NaN()
>> which doesn't exist. Fix this by setting a sane default for
>> debounce.
>>
>> Reported-by: Arnd Bergmann <arnd@arndb.de>
>> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
>> ---
>> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
>> index 1cb8fda7a166..27add04676e1 100644
>> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
>> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
>> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
>> bool pull_up;
>>
>> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
>> - kpd_delay = 0;
>> + kpd_delay = 15625;
> Should "debounce" even be optional? I'm wondering if we should just
> make it required...
Hmm maybe. It's not like things won't work without it set though.
>
> At the very least this default value should be documented in the DT
> binding.
>
I never understood this. The default value is something that is entirely
software driven. It could change at any time. If DT implementers aren't
specifying it they're saying "I don't care what the value is, let the
driver decide if they care". They're not saying, "Oh, that default value
in the binding is good enough for me so I don't need to specify this".
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time
2014-03-31 18:29 ` Stephen Boyd
@ 2014-05-14 19:02 ` Dmitry Torokhov
0 siblings, 0 replies; 6+ messages in thread
From: Dmitry Torokhov @ 2014-05-14 19:02 UTC (permalink / raw)
To: Stephen Boyd
Cc: linux-arm-msm, Arnd Bergmann, linux-kernel, linux-arm-kernel,
linux-input
On Mon, Mar 31, 2014 at 11:29:27AM -0700, Stephen Boyd wrote:
> On 03/31/14 11:23, Dmitry Torokhov wrote:
> > On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote:
> >> If the debounce time is 0 our usage of ilog2() later on in this
> >> driver will cause undefined behavior. If CONFIG_OF=n this fact is
> >> evident to the compiler, and it emits a call to ____ilog2_NaN()
> >> which doesn't exist. Fix this by setting a sane default for
> >> debounce.
> >>
> >> Reported-by: Arnd Bergmann <arnd@arndb.de>
> >> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> >> ---
> >> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
> >> index 1cb8fda7a166..27add04676e1 100644
> >> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
> >> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
> >> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> >> bool pull_up;
> >>
> >> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
> >> - kpd_delay = 0;
> >> + kpd_delay = 15625;
> > What if somebody supplied 0 via DT? Can we check and return -EINVAL?
>
> Sure. Here's a v2.
>
> -----8<------
> From: Stephen Boyd <sboyd@codeaurora.org>
> Subject: [PATCH v2] Input: pmic8xxx-pwrkey - Set sane default for debounce
> time
>
> If the debounce time is 0 our usage of ilog2() later on in this
> driver will cause undefined behavior. If CONFIG_OF=n this fact is
> evident to the compiler, and it emits a call to ____ilog2_NaN()
> which doesn't exist. Fix this by setting a sane default for
> debounce and failing to probe if debounce is 0 in the DT.
>
> Reported-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Applied, thank you. Sorry for the delay.
--
Dmitry
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-05-14 19:02 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2014-03-31 18:14 [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time Stephen Boyd
2014-03-31 18:23 ` Dmitry Torokhov
2014-03-31 18:29 ` Stephen Boyd
2014-05-14 19:02 ` Dmitry Torokhov
2014-03-31 18:23 ` Josh Cartwright
2014-03-31 18:48 ` Stephen Boyd
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