[PATCH v2 0/3] PM / devfreq: Fix the bug and add reviewer for devfreq support

[PATCH v2 0/3] PM / devfreq: Fix the bug and add reviewer for devfreq support

[Chanwoo Choi]

This patches fix the bug of devfreq_add_device() when governor name is wrong
and the wrong return value of probe() function for exynos_bus.c driver.

And I've been helping reviewing and tesing the devfreq support patches
for the couple of years. Also, I'm going to contribute the improvement
for devfreq subsystem. It would be easier for me for review if I'm cc'ed
for patches. So, patch1 adds myself as a reviewer for devfreq support.

Changes from v1:
(https://lkml.org/lkml/2016/12/15/122)
- Rebase these patches on v4.10-rc1.

Chanwoo Choi (3):
  MAINTAINERS: Add myself as reviewer for DEVFREQ subsystem support
  PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL
  PM / devfreq: exynos-bus: Fix the wrong return value

 MAINTAINERS                  |  1 +
 drivers/devfreq/devfreq.c    | 15 ++++++++++-----
 drivers/devfreq/exynos-bus.c |  2 +-
 3 files changed, 12 insertions(+), 6 deletions(-)

-- 
1.9.1

[PATCH v2 1/3] MAINTAINERS: Add myself as reviewer for DEVFREQ subsystem support

[Chanwoo Choi]

Add myself to the DEVFREQ entry as reviewer, I've been helping reviewing
and tesing the devfreq support patches for the couple of years. Also,
I'm going to contribute the improvement for devfreq subsystem. It would
be easier for me for review if I'm cc'ed for patches.

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 MAINTAINERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index cfff2c9e3d94..1a857698ac80 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3800,6 +3800,7 @@ F:	include/linux/devcoredump.h
 DEVICE FREQUENCY (DEVFREQ)
 M:	MyungJoo Ham <myungjoo.ham@samsung.com>
 M:	Kyungmin Park <kyungmin.park@samsung.com>
+R:	Chanwoo Choi <cw00.choi@samsung.com>
 L:	linux-pm@vger.kernel.org
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq.git
 S:	Maintained
-- 
1.9.1

[PATCH v2 2/3] PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL

[Chanwoo Choi]

This patch fixes the bug of devfreq_add_device(). The devfreq device must
have the default governor. If find_devfreq_governor() returns error,
devfreq_add_device() fail to add the devfreq instance.

Fixes: 1b5c1be2c88e ("PM / devfreq: map devfreq drivers to governor using name")
Cc: stable@vger.kernel.org
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/devfreq.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index a324801d6a66..47206a21bb90 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -593,11 +593,16 @@ struct devfreq *devfreq_add_device(struct device *dev,
 	list_add(&devfreq->node, &devfreq_list);
 
 	governor = find_devfreq_governor(devfreq->governor_name);
-	if (!IS_ERR(governor))
-		devfreq->governor = governor;
-	if (devfreq->governor)
-		err = devfreq->governor->event_handler(devfreq,
-					DEVFREQ_GOV_START, NULL);
+	if (IS_ERR(governor)) {
+		dev_err(dev, "%s: Unable to find governor for the device\n",
+			__func__);
+		err = PTR_ERR(governor);
+		goto err_init;
+	}
+
+	devfreq->governor = governor;
+	err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START,
+						NULL);
 	if (err) {
 		dev_err(dev, "%s: Unable to start governor for the device\n",
 			__func__);
-- 
1.9.1

[PATCH v2 3/3] PM / devfreq: exynos-bus: Fix the wrong return value

[Chanwoo Choi]

This patch fixes the wrong return value. If devfreq driver requires the wrong
and non-available governor, it is fail. So, this patch returns the error
insead of -EPROBE_DEFER.

Fixes: 403e0689d2a9 ("PM / devfreq: exynos: Add support of bus frequency of
		      sub-blocks using passive governor")
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: linux-samsung-soc@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/exynos-bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
index a8ed7792ece2..9af86f46fbec 100644
--- a/drivers/devfreq/exynos-bus.c
+++ b/drivers/devfreq/exynos-bus.c
@@ -497,7 +497,7 @@ static int exynos_bus_probe(struct platform_device *pdev)
 	if (IS_ERR(bus->devfreq)) {
 		dev_err(dev,
 			"failed to add devfreq dev with passive governor\n");
-		ret = -EPROBE_DEFER;
+		ret = PTR_ERR(bus->devfreq);
 		goto err;
 	}
 
-- 
1.9.1

Re: [PATCH v2 1/3] MAINTAINERS: Add myself as reviewer for DEVFREQ subsystem support

[MyungJoo Ham]

On Wed, Dec 28, 2016 at 8:52 PM, Chanwoo Choi <cw00.choi@samsung.com> wrote:
> Add myself to the DEVFREQ entry as reviewer, I've been helping reviewing
> and tesing the devfreq support patches for the couple of years. Also,
> I'm going to contribute the improvement for devfreq subsystem. It would
> be easier for me for review if I'm cc'ed for patches.
>
> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>

> ---
>  MAINTAINERS | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cfff2c9e3d94..1a857698ac80 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3800,6 +3800,7 @@ F:        include/linux/devcoredump.h
>  DEVICE FREQUENCY (DEVFREQ)
>  M:     MyungJoo Ham <myungjoo.ham@samsung.com>
>  M:     Kyungmin Park <kyungmin.park@samsung.com>
> +R:     Chanwoo Choi <cw00.choi@samsung.com>
>  L:     linux-pm@vger.kernel.org
>  T:     git git://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq.git
>  S:     Maintained
> --
> 1.9.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
MyungJoo Ham, Ph.D.
S/W Center, Samsung Electronics

Re: [PATCH v2 0/3] PM / devfreq: Fix the bug and add reviewer for devfreq support

[Chanwoo Choi]

Dear Myungjoo,

Thanks for your review for patch1.
But, patch2/3 is not yet reviewed. Could you please review these patches?

2016-12-28 20:52 GMT+09:00 Chanwoo Choi <cw00.choi@samsung.com>:
> This patches fix the bug of devfreq_add_device() when governor name is wrong
> and the wrong return value of probe() function for exynos_bus.c driver.
>
> And I've been helping reviewing and tesing the devfreq support patches
> for the couple of years. Also, I'm going to contribute the improvement
> for devfreq subsystem. It would be easier for me for review if I'm cc'ed
> for patches. So, patch1 adds myself as a reviewer for devfreq support.
>
> Changes from v1:
> (https://lkml.org/lkml/2016/12/15/122)
> - Rebase these patches on v4.10-rc1.
>
> Chanwoo Choi (3):
>   MAINTAINERS: Add myself as reviewer for DEVFREQ subsystem support
>   PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL
>   PM / devfreq: exynos-bus: Fix the wrong return value
>
>  MAINTAINERS                  |  1 +
>  drivers/devfreq/devfreq.c    | 15 ++++++++++-----
>  drivers/devfreq/exynos-bus.c |  2 +-
>  3 files changed, 12 insertions(+), 6 deletions(-)
>
> --
> 1.9.1
>



-- 
Best Regards,
Chanwoo Choi

Re: [PATCH v2 0/3] PM / devfreq: Fix the bug and add reviewer for devfreq support

[Rafael J. Wysocki]

On Tue, Jan 3, 2017 at 12:54 PM, Chanwoo Choi <cwchoi00@gmail.com> wrote:
> Dear Myungjoo,
>
> Thanks for your review for patch1.
> But, patch2/3 is not yet reviewed. Could you please review these patches?

I queued them up as 4.10 fixes in the meantime.

Thanks,
Rafael

Re: [PATCH v2 0/3] PM / devfreq: Fix the bug and add reviewer for devfreq support

[Chanwoo Choi]

Dear Rafael,

On 2017년 01월 04일 06:58, Rafael J. Wysocki wrote:
> On Tue, Jan 3, 2017 at 12:54 PM, Chanwoo Choi <cwchoi00@gmail.com> wrote:
>> Dear Myungjoo,
>>
>> Thanks for your review for patch1.
>> But, patch2/3 is not yet reviewed. Could you please review these patches?
> 
> I queued them up as 4.10 fixes in the meantime.

Thanks for picking up the patches.

-- 
Regards,
Chanwoo Choi