diff mbox series

wifi: wilc1000: Do not operate uninitialized hardware during suspend/resume

Message ID 20240821183639.163187-1-marex@denx.de (mailing list archive)
State Accepted
Commit b0dc7018477e8fbb7e40c908c29cf663d06b17a7
Delegated to: Kalle Valo
Headers show
Series wifi: wilc1000: Do not operate uninitialized hardware during suspend/resume | expand

Commit Message

Marek Vasut Aug. 21, 2024, 6:36 p.m. UTC
In case the hardware is not initialized, do not operate it during
suspend/resume cycle, the hardware is already off so there is no
reason to access it.

In fact, wilc_sdio_enable_interrupt() in the resume callback does
interfere with the same call when initializing the hardware after
resume and makes such initialization after resume fail. Fix this
by not operating uninitialized hardware during suspend/resume.

Signed-off-by: Marek Vasut <marex@denx.de>
---
Cc: Ajay Singh <ajay.kathat@microchip.com>
Cc: Alexis Lothoré <alexis.lothore@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Marek Vasut <marex@denx.de>
Cc: linux-wireless@vger.kernel.org
---
 drivers/net/wireless/microchip/wilc1000/sdio.c | 7 +++++++
 1 file changed, 7 insertions(+)

Comments

Ajay Singh Aug. 23, 2024, 5:16 p.m. UTC | #1
Hi Marek,

On 8/21/24 11:36, Marek Vasut wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> In case the hardware is not initialized, do not operate it during
> suspend/resume cycle, the hardware is already off so there is no
> reason to access it.
> 
> In fact, wilc_sdio_enable_interrupt() in the resume callback does
> interfere with the same call when initializing the hardware after
> resume and makes such initialization after resume fail. Fix this
> by not operating uninitialized hardware during suspend/resume.

Is this behavior observed then power-save is enabled when interface is not up.
Ideally registers read/write commands should pass as soon the wilc module is
up. But anyway, it is good have this check to avoid these commands. if
possible, please add the similar check for wilc_spi_suspend/resume() to have
similar behavior.

> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> ---
> Cc: Ajay Singh <ajay.kathat@microchip.com>
> Cc: Alexis Lothoré <alexis.lothore@bootlin.com>
> Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
> Cc: Kalle Valo <kvalo@kernel.org>
> Cc: Marek Vasut <marex@denx.de>
> Cc: linux-wireless@vger.kernel.org
> ---
>  drivers/net/wireless/microchip/wilc1000/sdio.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/net/wireless/microchip/wilc1000/sdio.c b/drivers/net/wireless/microchip/wilc1000/sdio.c
> index 0043f7a0fdf97..7999aeb76901f 100644
> --- a/drivers/net/wireless/microchip/wilc1000/sdio.c
> +++ b/drivers/net/wireless/microchip/wilc1000/sdio.c
> @@ -977,6 +977,9 @@ static int wilc_sdio_suspend(struct device *dev)
> 
>         dev_info(dev, "sdio suspend\n");
> 
> +       if (!wilc->initialized)
> +               return 0;
> +
>         if (!IS_ERR(wilc->rtc_clk))
>                 clk_disable_unprepare(wilc->rtc_clk);
> 
> @@ -999,6 +1002,10 @@ static int wilc_sdio_resume(struct device *dev)
>         struct wilc *wilc = sdio_get_drvdata(func);
> 
>         dev_info(dev, "sdio resume\n");
> +
> +       if (!wilc->initialized)
> +               return 0;
> +
>         wilc_sdio_init(wilc, true);
>         wilc_sdio_enable_interrupt(wilc);
> 
> --
> 2.43.0
>
Marek Vasut Aug. 23, 2024, 8:34 p.m. UTC | #2
On 8/23/24 7:16 PM, Ajay.Kathat@microchip.com wrote:
> Hi Marek,

Hi,

> On 8/21/24 11:36, Marek Vasut wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> In case the hardware is not initialized, do not operate it during
>> suspend/resume cycle, the hardware is already off so there is no
>> reason to access it.
>>
>> In fact, wilc_sdio_enable_interrupt() in the resume callback does
>> interfere with the same call when initializing the hardware after
>> resume and makes such initialization after resume fail. Fix this
>> by not operating uninitialized hardware during suspend/resume.
> 
> Is this behavior observed then power-save is enabled when interface is not up.

This is observed when the system with WILC3000 boots (wilc3000 is not 
if-up'd or anything) and is suspended and resumed, as simple as that.
Alexis Lothoré (eBPF Foundation) Aug. 27, 2024, 9:21 a.m. UTC | #3
On 8/23/24 19:16, Ajay.Kathat@microchip.com wrote:
> Hi Marek,
> 
> On 8/21/24 11:36, Marek Vasut wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> In case the hardware is not initialized, do not operate it during
>> suspend/resume cycle, the hardware is already off so there is no
>> reason to access it.
>>
>> In fact, wilc_sdio_enable_interrupt() in the resume callback does
>> interfere with the same call when initializing the hardware after
>> resume and makes such initialization after resume fail. Fix this
>> by not operating uninitialized hardware during suspend/resume.
> 
> Is this behavior observed then power-save is enabled when interface is not up.
> Ideally registers read/write commands should pass as soon the wilc module is
> up. But anyway, it is good have this check to avoid these commands. if
> possible, please add the similar check for wilc_spi_suspend/resume() to have
> similar behavior.

It looks like there is a hole and that no PM ops are implemented in the upstream
driver on spi side. That may be a miss from me when I sent the power management
series a few months ago. I'll fix that.

So for this change:

Reviewed-by: Alexis Lothoré <alexis.lothore@bootlin.com>

> 
>>
>> Signed-off-by: Marek Vasut <marex@denx.de>
>> ---
>> Cc: Ajay Singh <ajay.kathat@microchip.com>
>> Cc: Alexis Lothoré <alexis.lothore@bootlin.com>
>> Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
>> Cc: Kalle Valo <kvalo@kernel.org>
>> Cc: Marek Vasut <marex@denx.de>
>> Cc: linux-wireless@vger.kernel.org
>> ---
>>  drivers/net/wireless/microchip/wilc1000/sdio.c | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/drivers/net/wireless/microchip/wilc1000/sdio.c b/drivers/net/wireless/microchip/wilc1000/sdio.c
>> index 0043f7a0fdf97..7999aeb76901f 100644
>> --- a/drivers/net/wireless/microchip/wilc1000/sdio.c
>> +++ b/drivers/net/wireless/microchip/wilc1000/sdio.c
>> @@ -977,6 +977,9 @@ static int wilc_sdio_suspend(struct device *dev)
>>
>>         dev_info(dev, "sdio suspend\n");
>>
>> +       if (!wilc->initialized)
>> +               return 0;
>> +
>>         if (!IS_ERR(wilc->rtc_clk))
>>                 clk_disable_unprepare(wilc->rtc_clk);
>>
>> @@ -999,6 +1002,10 @@ static int wilc_sdio_resume(struct device *dev)
>>         struct wilc *wilc = sdio_get_drvdata(func);
>>
>>         dev_info(dev, "sdio resume\n");
>> +
>> +       if (!wilc->initialized)
>> +               return 0;
>> +
>>         wilc_sdio_init(wilc, true);
>>         wilc_sdio_enable_interrupt(wilc);
>>
>> --
>> 2.43.0
>>
>
Kalle Valo Sept. 3, 2024, 6:30 p.m. UTC | #4
Marek Vasut <marex@denx.de> wrote:

> In case the hardware is not initialized, do not operate it during
> suspend/resume cycle, the hardware is already off so there is no
> reason to access it.
> 
> In fact, wilc_sdio_enable_interrupt() in the resume callback does
> interfere with the same call when initializing the hardware after
> resume and makes such initialization after resume fail. Fix this
> by not operating uninitialized hardware during suspend/resume.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> Reviewed-by: Alexis Lothoré <alexis.lothore@bootlin.com>

Patch applied to wireless-next.git, thanks.

b0dc7018477e wifi: wilc1000: Do not operate uninitialized hardware during suspend/resume
diff mbox series

Patch

diff --git a/drivers/net/wireless/microchip/wilc1000/sdio.c b/drivers/net/wireless/microchip/wilc1000/sdio.c
index 0043f7a0fdf97..7999aeb76901f 100644
--- a/drivers/net/wireless/microchip/wilc1000/sdio.c
+++ b/drivers/net/wireless/microchip/wilc1000/sdio.c
@@ -977,6 +977,9 @@  static int wilc_sdio_suspend(struct device *dev)
 
 	dev_info(dev, "sdio suspend\n");
 
+	if (!wilc->initialized)
+		return 0;
+
 	if (!IS_ERR(wilc->rtc_clk))
 		clk_disable_unprepare(wilc->rtc_clk);
 
@@ -999,6 +1002,10 @@  static int wilc_sdio_resume(struct device *dev)
 	struct wilc *wilc = sdio_get_drvdata(func);
 
 	dev_info(dev, "sdio resume\n");
+
+	if (!wilc->initialized)
+		return 0;
+
 	wilc_sdio_init(wilc, true);
 	wilc_sdio_enable_interrupt(wilc);