Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Hi Jonathan,
On Mon, Aug 15, 2016 at 07:04:31PM +0100, Jonathan Cameron wrote:
> On 26/07/16 04:22, Guenter Roeck wrote:
> > On 07/25/2016 07:51 PM, Caesar Wang wrote:
> >> Hi Guenter,
> >>
> >> Thanks for fixing it.
> >>
> >> On 2016年07月26日 03:39, Guenter Roeck wrote:
> >>> If the ADC is read for the first time, the caller gets a timeout error,
> >>> and the kernel log shows
> >>>
> >>> read channel() error: -110
> >>>
> >>> The ADC may be enabled on boot, and needs to be explicitly disabled
> >>> for a read sequence to work (otherwise there is no completion interrupt).
> >>> Disaple it explicitly in the probe function.
> >>>
> >>> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
> >>> Signed-off-by: Guenter Roeck
> >>> ---
> >>> drivers/iio/adc/rockchip_saradc.c | 3 +++
> >>> 1 file changed, 3 insertions(+)
> >>>
> >>> diff --git a/drivers/iio/adc/rockchip_saradc.c
> >>> b/drivers/iio/adc/rockchip_saradc.c
> >>> index f9ad6c2d6821..6aa3271d86b5 100644
> >>> --- a/drivers/iio/adc/rockchip_saradc.c
> >>> +++ b/drivers/iio/adc/rockchip_saradc.c
> >>> @@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct
> >>> platform_device *pdev)
> >>> goto err_pclk;
> >>> }
> >>> +/* Make sure ADC is disabled */
> >>> +writel_relaxed(0, info->regs + SARADC_CTRL);
> >>
> >> I think we should reset the saradc controller.
> >> Since make sure the reset value is 0 and loader-->kernel may even cause
> >> harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
> >>
> >>
> >> e.g.:
> >> /**
> >> * Reset SARADC Controller, reset all saradc registers.
> >> */
> >> static void rockchip_saradc_reset_controller(struct reset_control *reset)
> >> {
> >> reset_control_assert(reset);
> >> usleep_range(10, 20);
> >> reset_control_deassert(reset);
> >> }
> >>
> >> ..probe()
> >> {
> >> ...
> >> rockchip_saradc_reset_controller();
> >> ...
> >> }
> >>
> >
> > Ok, I'll give it a try.
> >
> > Guenter
> Could you confirm if this patch is superseded by that
> change or not?
Yes, that is correct. The version using the reset has been applied to
chromeos-4.4 [1] with commit 86aeb7c3f ("FROMLIST: iio: adc: rockchip_saradc:
reset saradc controller before programming it").
Thanks,
Guenter
---
[1] https://chromium.googlesource.com/chromiumos/third_party/kernel
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Hi Jonathan,
On Mon, Aug 15, 2016 at 07:04:31PM +0100, Jonathan Cameron wrote:
> On 26/07/16 04:22, Guenter Roeck wrote:
> > On 07/25/2016 07:51 PM, Caesar Wang wrote:
> >> Hi Guenter,
> >>
> >> Thanks for fixing it.
> >>
> >> On 2016年07月26日 03:39, Guenter Roeck wrote:
> >>> If the ADC is read for the first time, the caller gets a timeout error,
> >>> and the kernel log shows
> >>>
> >>> read channel() error: -110
> >>>
> >>> The ADC may be enabled on boot, and needs to be explicitly disabled
> >>> for a read sequence to work (otherwise there is no completion interrupt).
> >>> Disaple it explicitly in the probe function.
> >>>
> >>> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
> >>> Signed-off-by: Guenter Roeck
> >>> ---
> >>> drivers/iio/adc/rockchip_saradc.c | 3 +++
> >>> 1 file changed, 3 insertions(+)
> >>>
> >>> diff --git a/drivers/iio/adc/rockchip_saradc.c
> >>> b/drivers/iio/adc/rockchip_saradc.c
> >>> index f9ad6c2d6821..6aa3271d86b5 100644
> >>> --- a/drivers/iio/adc/rockchip_saradc.c
> >>> +++ b/drivers/iio/adc/rockchip_saradc.c
> >>> @@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct
> >>> platform_device *pdev)
> >>> goto err_pclk;
> >>> }
> >>> +/* Make sure ADC is disabled */
> >>> +writel_relaxed(0, info->regs + SARADC_CTRL);
> >>
> >> I think we should reset the saradc controller.
> >> Since make sure the reset value is 0 and loader-->kernel may even cause
> >> harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
> >>
> >>
> >> e.g.:
> >> /**
> >> * Reset SARADC Controller, reset all saradc registers.
> >> */
> >> static void rockchip_saradc_reset_controller(struct reset_control *reset)
> >> {
> >> reset_control_assert(reset);
> >> usleep_range(10, 20);
> >> reset_control_deassert(reset);
> >> }
> >>
> >> ..probe()
> >> {
> >> ...
> >> rockchip_saradc_reset_controller();
> >> ...
> >> }
> >>
> >
> > Ok, I'll give it a try.
> >
> > Guenter
> Could you confirm if this patch is superseded by that
> change or not?
Yes, that is correct. The version using the reset has been applied to
chromeos-4.4 [1] with commit 86aeb7c3f ("FROMLIST: iio: adc: rockchip_saradc:
reset saradc controller before programming it").
Thanks,
Guenter
---
[1] https://chromium.googlesource.com/chromiumos/third_party/kernel
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 26/07/16 04:22, Guenter Roeck wrote:
> On 07/25/2016 07:51 PM, Caesar Wang wrote:
>> Hi Guenter,
>>
>> Thanks for fixing it.
>>
>> On 2016年07月26日 03:39, Guenter Roeck wrote:
>>> If the ADC is read for the first time, the caller gets a timeout error,
>>> and the kernel log shows
>>>
>>> read channel() error: -110
>>>
>>> The ADC may be enabled on boot, and needs to be explicitly disabled
>>> for a read sequence to work (otherwise there is no completion interrupt).
>>> Disaple it explicitly in the probe function.
>>>
>>> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
>>> Signed-off-by: Guenter Roeck
>>> ---
>>> drivers/iio/adc/rockchip_saradc.c | 3 +++
>>> 1 file changed, 3 insertions(+)
>>>
>>> diff --git a/drivers/iio/adc/rockchip_saradc.c
>>> b/drivers/iio/adc/rockchip_saradc.c
>>> index f9ad6c2d6821..6aa3271d86b5 100644
>>> --- a/drivers/iio/adc/rockchip_saradc.c
>>> +++ b/drivers/iio/adc/rockchip_saradc.c
>>> @@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
>>> *pdev)
>>> goto err_pclk;
>>> }
>>> +/* Make sure ADC is disabled */
>>> +writel_relaxed(0, info->regs + SARADC_CTRL);
>>
>> I think we should reset the saradc controller.
>> Since make sure the reset value is 0 and loader-->kernel may even cause
>> harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
>>
>>
>> e.g.:
>> /**
>> * Reset SARADC Controller, reset all saradc registers.
>> */
>> static void rockchip_saradc_reset_controller(struct reset_control *reset)
>> {
>> reset_control_assert(reset);
>> usleep_range(10, 20);
>> reset_control_deassert(reset);
>> }
>>
>> ..probe()
>> {
>> ...
>> rockchip_saradc_reset_controller();
>> ...
>> }
>>
>
> Ok, I'll give it a try.
>
> Guenter
Could you confirm if this patch is superseded by that
change or not?
>
>>
>> -
>> Caesar
>>
>>> +
>>> platform_set_drvdata(pdev, indio_dev);
>>> indio_dev->name = dev_name(>dev);
>>
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 26/07/16 04:22, Guenter Roeck wrote:
> On 07/25/2016 07:51 PM, Caesar Wang wrote:
>> Hi Guenter,
>>
>> Thanks for fixing it.
>>
>> On 2016年07月26日 03:39, Guenter Roeck wrote:
>>> If the ADC is read for the first time, the caller gets a timeout error,
>>> and the kernel log shows
>>>
>>> read channel() error: -110
>>>
>>> The ADC may be enabled on boot, and needs to be explicitly disabled
>>> for a read sequence to work (otherwise there is no completion interrupt).
>>> Disaple it explicitly in the probe function.
>>>
>>> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
>>> Signed-off-by: Guenter Roeck
>>> ---
>>> drivers/iio/adc/rockchip_saradc.c | 3 +++
>>> 1 file changed, 3 insertions(+)
>>>
>>> diff --git a/drivers/iio/adc/rockchip_saradc.c
>>> b/drivers/iio/adc/rockchip_saradc.c
>>> index f9ad6c2d6821..6aa3271d86b5 100644
>>> --- a/drivers/iio/adc/rockchip_saradc.c
>>> +++ b/drivers/iio/adc/rockchip_saradc.c
>>> @@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
>>> *pdev)
>>> goto err_pclk;
>>> }
>>> +/* Make sure ADC is disabled */
>>> +writel_relaxed(0, info->regs + SARADC_CTRL);
>>
>> I think we should reset the saradc controller.
>> Since make sure the reset value is 0 and loader-->kernel may even cause
>> harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
>>
>>
>> e.g.:
>> /**
>> * Reset SARADC Controller, reset all saradc registers.
>> */
>> static void rockchip_saradc_reset_controller(struct reset_control *reset)
>> {
>> reset_control_assert(reset);
>> usleep_range(10, 20);
>> reset_control_deassert(reset);
>> }
>>
>> ..probe()
>> {
>> ...
>> rockchip_saradc_reset_controller();
>> ...
>> }
>>
>
> Ok, I'll give it a try.
>
> Guenter
Could you confirm if this patch is superseded by that
change or not?
>
>>
>> -
>> Caesar
>>
>>> +
>>> platform_set_drvdata(pdev, indio_dev);
>>> indio_dev->name = dev_name(>dev);
>>
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 2016年07月26日 11:22, Guenter Roeck wrote:
On 07/25/2016 07:51 PM, Caesar Wang wrote:
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion
interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct
platform_device *pdev)
goto err_pclk;
}
+/* Make sure ADC is disabled */
+writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even
cause harm, as my experience on tsadc.
(drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control
*reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
Ok, I'll give it a try.
I posted it on https://patchwork.kernel.org/patch/9247661/
Guenter
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
___
Linux-rockchip mailing list
linux-rockc...@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rockchip
--
caesar wang | software engineer | w...@rock-chip.com
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 2016年07月26日 11:22, Guenter Roeck wrote:
On 07/25/2016 07:51 PM, Caesar Wang wrote:
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion
interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct
platform_device *pdev)
goto err_pclk;
}
+/* Make sure ADC is disabled */
+writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even
cause harm, as my experience on tsadc.
(drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control
*reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
Ok, I'll give it a try.
I posted it on https://patchwork.kernel.org/patch/9247661/
Guenter
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
___
Linux-rockchip mailing list
linux-rockc...@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-rockchip
--
caesar wang | software engineer | w...@rock-chip.com
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 07/25/2016 07:51 PM, Caesar Wang wrote:
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
*pdev)
goto err_pclk;
}
+/* Make sure ADC is disabled */
+writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even cause harm,
as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control *reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
Ok, I'll give it a try.
Guenter
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
On 07/25/2016 07:51 PM, Caesar Wang wrote:
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
*pdev)
goto err_pclk;
}
+/* Make sure ADC is disabled */
+writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even cause harm,
as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control *reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
Ok, I'll give it a try.
Guenter
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
*pdev)
goto err_pclk;
}
+ /* Make sure ADC is disabled */
+ writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even cause
harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control *reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
--
caesar wang | software engineer | w...@rock-chip.com
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Hi Guenter,
Thanks for fixing it.
On 2016年07月26日 03:39, Guenter Roeck wrote:
If the ADC is read for the first time, the caller gets a timeout error,
and the kernel log shows
read channel() error: -110
The ADC may be enabled on boot, and needs to be explicitly disabled
for a read sequence to work (otherwise there is no completion interrupt).
Disaple it explicitly in the probe function.
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Guenter Roeck
---
drivers/iio/adc/rockchip_saradc.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/iio/adc/rockchip_saradc.c
b/drivers/iio/adc/rockchip_saradc.c
index f9ad6c2d6821..6aa3271d86b5 100644
--- a/drivers/iio/adc/rockchip_saradc.c
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -280,6 +280,9 @@ static int rockchip_saradc_probe(struct platform_device
*pdev)
goto err_pclk;
}
+ /* Make sure ADC is disabled */
+ writel_relaxed(0, info->regs + SARADC_CTRL);
I think we should reset the saradc controller.
Since make sure the reset value is 0 and loader-->kernel may even cause
harm, as my experience on tsadc. (drivers/thermal/rockchip_thermal.c)
e.g.:
/**
* Reset SARADC Controller, reset all saradc registers.
*/
static void rockchip_saradc_reset_controller(struct reset_control *reset)
{
reset_control_assert(reset);
usleep_range(10, 20);
reset_control_deassert(reset);
}
..probe()
{
...
rockchip_saradc_reset_controller();
...
}
-
Caesar
+
platform_set_drvdata(pdev, indio_dev);
indio_dev->name = dev_name(>dev);
--
caesar wang | software engineer | w...@rock-chip.com
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Am Montag, 25. Juli 2016, 12:39:00 schrieb Guenter Roeck:
> If the ADC is read for the first time, the caller gets a timeout error,
> and the kernel log shows
>
> read channel() error: -110
>
> The ADC may be enabled on boot, and needs to be explicitly disabled
> for a read sequence to work (otherwise there is no completion interrupt).
> Disaple it explicitly in the probe function.
>
> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
> Signed-off-by: Guenter Roeck
in my tests I hadn't notices that issue before, but that is likely because the
bootloaders I had didn't enable the saradc. Anyway, that looks definitly sane,
so
Reviewed-by: Heiko Stuebner
Re: [PATCH] iio: adc: rockchip_saradc: Explicitly disable ADC on probe
Am Montag, 25. Juli 2016, 12:39:00 schrieb Guenter Roeck:
> If the ADC is read for the first time, the caller gets a timeout error,
> and the kernel log shows
>
> read channel() error: -110
>
> The ADC may be enabled on boot, and needs to be explicitly disabled
> for a read sequence to work (otherwise there is no completion interrupt).
> Disaple it explicitly in the probe function.
>
> Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
> Signed-off-by: Guenter Roeck
in my tests I hadn't notices that issue before, but that is likely because the
bootloaders I had didn't enable the saradc. Anyway, that looks definitly sane,
so
Reviewed-by: Heiko Stuebner
