diff mbox

[1/5] pinctrl: samsung: Remove bogus irq_[un]mask from resource management

Message ID 20170629214343.882576048@linutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Thomas Gleixner June 29, 2017, 9:33 p.m. UTC
The irq chip callbacks irq_request/release_resources() have absolutely no
business with masking and unmasking the irq.

The core code unmasks the interrupt after complete setup and masks it
before invoking irq_release_resources().

The unmask is actually harmful as it happens before the interrupt is
completely initialized in __setup_irq().

Remove it.

Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-gpio@vger.kernel.org
---
 drivers/pinctrl/samsung/pinctrl-exynos.c |    4 ----
 1 file changed, 4 deletions(-)

Comments

Tomasz Figa June 30, 2017, 2:47 a.m. UTC | #1
Hi Thomas,

2017-06-30 6:33 GMT+09:00 Thomas Gleixner <tglx@linutronix.de>:
> The irq chip callbacks irq_request/release_resources() have absolutely no
> business with masking and unmasking the irq.
>
> The core code unmasks the interrupt after complete setup and masks it
> before invoking irq_release_resources().
>
> The unmask is actually harmful as it happens before the interrupt is
> completely initialized in __setup_irq().
>
> Remove it.

Good catch, thanks! (Note that the original patch of mine [1] did that
in .irq_startup()/.irq_shutdown(), which was for some reason changed
later, but I don't remember the exact story.)

[1] https://patchwork.kernel.org/patch/4466431/

Acked-by: Tomasz Figa <tomasz.figa@gmail.com>

Sylwester, Krzysztof, would you be able to do some basic test?

Best regards,
Tomasz

>
> Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Tomasz Figa <tomasz.figa@gmail.com>
> Cc: Krzysztof Kozlowski <krzk@kernel.org>
> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Kukjin Kim <kgene@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-samsung-soc@vger.kernel.org
> Cc: linux-gpio@vger.kernel.org
> ---
>  drivers/pinctrl/samsung/pinctrl-exynos.c |    4 ----
>  1 file changed, 4 deletions(-)
>
> --- a/drivers/pinctrl/samsung/pinctrl-exynos.c
> +++ b/drivers/pinctrl/samsung/pinctrl-exynos.c
> @@ -205,8 +205,6 @@ static int exynos_irq_request_resources(
>
>         spin_unlock_irqrestore(&bank->slock, flags);
>
> -       exynos_irq_unmask(irqd);
> -
>         return 0;
>  }
>
> @@ -226,8 +224,6 @@ static void exynos_irq_release_resources
>         shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC];
>         mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
>
> -       exynos_irq_mask(irqd);
> -
>         spin_lock_irqsave(&bank->slock, flags);
>
>         con = readl(bank->eint_base + reg_con);
>
>
Krzysztof Kozlowski June 30, 2017, 6:02 a.m. UTC | #2
On Fri, Jun 30, 2017 at 4:47 AM, Tomasz Figa <tomasz.figa@gmail.com> wrote:
> Hi Thomas,
>
> 2017-06-30 6:33 GMT+09:00 Thomas Gleixner <tglx@linutronix.de>:
>> The irq chip callbacks irq_request/release_resources() have absolutely no
>> business with masking and unmasking the irq.
>>
>> The core code unmasks the interrupt after complete setup and masks it
>> before invoking irq_release_resources().
>>
>> The unmask is actually harmful as it happens before the interrupt is
>> completely initialized in __setup_irq().
>>
>> Remove it.
>
> Good catch, thanks! (Note that the original patch of mine [1] did that
> in .irq_startup()/.irq_shutdown(), which was for some reason changed
> later, but I don't remember the exact story.)
>
> [1] https://patchwork.kernel.org/patch/4466431/
>
> Acked-by: Tomasz Figa <tomasz.figa@gmail.com>
>
> Sylwester, Krzysztof, would you be able to do some basic test?

I suppose this was not tested so yes - I have platforms do this. I
understand that checking any non-shared GPIO interrupt should be
sufficient to test, right?

Best regards,
Krzysztof
Tomasz Figa June 30, 2017, 6:20 a.m. UTC | #3
2017-06-30 15:02 GMT+09:00 Krzysztof Kozlowski <krzk@kernel.org>:
> On Fri, Jun 30, 2017 at 4:47 AM, Tomasz Figa <tomasz.figa@gmail.com> wrote:
>> Hi Thomas,
>>
>> 2017-06-30 6:33 GMT+09:00 Thomas Gleixner <tglx@linutronix.de>:
>>> The irq chip callbacks irq_request/release_resources() have absolutely no
>>> business with masking and unmasking the irq.
>>>
>>> The core code unmasks the interrupt after complete setup and masks it
>>> before invoking irq_release_resources().
>>>
>>> The unmask is actually harmful as it happens before the interrupt is
>>> completely initialized in __setup_irq().
>>>
>>> Remove it.
>>
>> Good catch, thanks! (Note that the original patch of mine [1] did that
>> in .irq_startup()/.irq_shutdown(), which was for some reason changed
>> later, but I don't remember the exact story.)
>>
>> [1] https://patchwork.kernel.org/patch/4466431/
>>
>> Acked-by: Tomasz Figa <tomasz.figa@gmail.com>
>>
>> Sylwester, Krzysztof, would you be able to do some basic test?
>
> I suppose this was not tested so yes - I have platforms do this. I
> understand that checking any non-shared GPIO interrupt should be
> sufficient to test, right?

I think any interrupt from the Exynos pin controller should work, even
shared one. I'd expect irq_request_resources() to be invoked for
shared interrupts as well, otherwise we have a problem... (I quickly
looked through kernel/irq/manage.c and it seems to be invoked for the
first __setup_irq() call even for shared interrupts.)

Thanks.

Best regards,
Tomasz
Linus Walleij June 30, 2017, 12:12 p.m. UTC | #4
On Thu, Jun 29, 2017 at 11:33 PM, Thomas Gleixner <tglx@linutronix.de> wrote:

> The irq chip callbacks irq_request/release_resources() have absolutely no
> business with masking and unmasking the irq.
>
> The core code unmasks the interrupt after complete setup and masks it
> before invoking irq_release_resources().
>
> The unmask is actually harmful as it happens before the interrupt is
> completely initialized in __setup_irq().
>
> Remove it.
>
> Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Tomasz Figa <tomasz.figa@gmail.com>
> Cc: Krzysztof Kozlowski <krzk@kernel.org>
> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Kukjin Kim <kgene@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-samsung-soc@vger.kernel.org
> Cc: linux-gpio@vger.kernel.org

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Does this patch have a dependency on the rest of the series or should
I just apply it as-is?

Yours,
Linus Walleij
Thomas Gleixner June 30, 2017, 12:17 p.m. UTC | #5
On Fri, 30 Jun 2017, Linus Walleij wrote:
> On Thu, Jun 29, 2017 at 11:33 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> > The irq chip callbacks irq_request/release_resources() have absolutely no
> > business with masking and unmasking the irq.
> >
> > The core code unmasks the interrupt after complete setup and masks it
> > before invoking irq_release_resources().
> >
> > The unmask is actually harmful as it happens before the interrupt is
> > completely initialized in __setup_irq().
> >
> > Remove it.
> >
> > Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> > Cc: Tomasz Figa <tomasz.figa@gmail.com>
> > Cc: Krzysztof Kozlowski <krzk@kernel.org>
> > Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> > Cc: Linus Walleij <linus.walleij@linaro.org>
> > Cc: Kukjin Kim <kgene@kernel.org>
> > Cc: linux-arm-kernel@lists.infradead.org
> > Cc: linux-samsung-soc@vger.kernel.org
> > Cc: linux-gpio@vger.kernel.org
> 
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> 
> Does this patch have a dependency on the rest of the series or should
> I just apply it as-is?

Has no dependecies at all.
Linus Walleij June 30, 2017, 1:53 p.m. UTC | #6
On Thu, Jun 29, 2017 at 11:33 PM, Thomas Gleixner <tglx@linutronix.de> wrote:

> The irq chip callbacks irq_request/release_resources() have absolutely no
> business with masking and unmasking the irq.
>
> The core code unmasks the interrupt after complete setup and masks it
> before invoking irq_release_resources().
>
> The unmask is actually harmful as it happens before the interrupt is
> completely initialized in __setup_irq().
>
> Remove it.
>
> Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Tomasz Figa <tomasz.figa@gmail.com>
> Cc: Krzysztof Kozlowski <krzk@kernel.org>
> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Kukjin Kim <kgene@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-samsung-soc@vger.kernel.org
> Cc: linux-gpio@vger.kernel.org

Patch applied directly since it has no deps and fixes queued stuff for v4.13.
I guess Krysztof will make sure it doesn't break anything.

Yours,
Linus Walleij
Krzysztof Kozlowski June 30, 2017, 2:58 p.m. UTC | #7
On Fri, Jun 30, 2017 at 03:53:18PM +0200, Linus Walleij wrote:
> On Thu, Jun 29, 2017 at 11:33 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> > The irq chip callbacks irq_request/release_resources() have absolutely no
> > business with masking and unmasking the irq.
> >
> > The core code unmasks the interrupt after complete setup and masks it
> > before invoking irq_release_resources().
> >
> > The unmask is actually harmful as it happens before the interrupt is
> > completely initialized in __setup_irq().
> >
> > Remove it.
> >
> > Fixes: f6a8249f9e55 ("pinctrl: exynos: Lock GPIOs as interrupts when used as EINTs")
> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> > Cc: Tomasz Figa <tomasz.figa@gmail.com>
> > Cc: Krzysztof Kozlowski <krzk@kernel.org>
> > Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
> > Cc: Linus Walleij <linus.walleij@linaro.org>
> > Cc: Kukjin Kim <kgene@kernel.org>
> > Cc: linux-arm-kernel@lists.infradead.org
> > Cc: linux-samsung-soc@vger.kernel.org
> > Cc: linux-gpio@vger.kernel.org
> 
> Patch applied directly since it has no deps and fixes queued stuff for v4.13.
> I guess Krysztof will make sure it doesn't break anything.

Everything seems to work fine with the patchset.

Best regards,
Krzysztof
diff mbox

Patch

--- a/drivers/pinctrl/samsung/pinctrl-exynos.c
+++ b/drivers/pinctrl/samsung/pinctrl-exynos.c
@@ -205,8 +205,6 @@  static int exynos_irq_request_resources(
 
 	spin_unlock_irqrestore(&bank->slock, flags);
 
-	exynos_irq_unmask(irqd);
-
 	return 0;
 }
 
@@ -226,8 +224,6 @@  static void exynos_irq_release_resources
 	shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC];
 	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 
-	exynos_irq_mask(irqd);
-
 	spin_lock_irqsave(&bank->slock, flags);
 
 	con = readl(bank->eint_base + reg_con);