[PATCH v2] iio: adc: ad7173: fix num_slots

[PATCH v2] iio: adc: ad7173: fix num_slots

[David Lechner]

Fix the num_slots value for most chips in the ad7173 driver. The correct
value is the number of CHANNELx registers on the chip.

In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
to be static const data instead of being dynamically populated during
driver probe. However, there was an existing bug in commit 76a1e6a42802
("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
set to the number of CONFIGx registers instead of the number of
CHANNELx registers. This bug was partially propagated to the refactored
code in that the 16-channel chips were only given 8 slots instead of
16 although we did managed to fix the 8-channel chips and one of the
4-channel chips in that commit. However, we botched two of the 4-channel
chips and ended up incorrectly giving them 8 slots during the
refactoring.

This patch fixes that mistake on the 4-channel chips and also
corrects the 16-channel chips to have 16 slots.

Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
Signed-off-by: David Lechner <dlechner@baylibre.com>
---
Changes in v2:
- Improve commit message.
- Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
---
 drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
 1 file changed, 27 insertions(+), 10 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
 	.num_slots = 8,
 };
 
+static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
+	.set_channel = ad7173_set_channel,
+	.append_status = ad7173_append_status,
+	.disable_all = ad7173_disable_all,
+	.disable_one = ad7173_disable_one,
+	.set_mode = ad7173_set_mode,
+	.has_registers = true,
+	.has_named_irqs = true,
+	.supports_spi_offload = true,
+	.addr_shift = 0,
+	.read_mask = BIT(6),
+	.status_ch_mask = GENMASK(3, 0),
+	.data_reg = AD7173_REG_DATA,
+	.num_resetclks = 64,
+	.num_slots = 16,
+};
+
 static const struct ad7173_device_info ad4111_device_info = {
 	.name = "ad4111",
 	.id = AD4111_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 8,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -796,7 +813,7 @@ static const struct ad7173_device_info ad4111_device_info = {
 static const struct ad7173_device_info ad4112_device_info = {
 	.name = "ad4112",
 	.id = AD4112_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 8,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -817,7 +834,7 @@ static const struct ad7173_device_info ad4112_device_info = {
 static const struct ad7173_device_info ad4113_device_info = {
 	.name = "ad4113",
 	.id = AD4113_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 8,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -836,7 +853,7 @@ static const struct ad7173_device_info ad4113_device_info = {
 static const struct ad7173_device_info ad4114_device_info = {
 	.name = "ad4114",
 	.id = AD4114_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 16,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -855,7 +872,7 @@ static const struct ad7173_device_info ad4114_device_info = {
 static const struct ad7173_device_info ad4115_device_info = {
 	.name = "ad4115",
 	.id = AD4115_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 16,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -874,7 +891,7 @@ static const struct ad7173_device_info ad4115_device_info = {
 static const struct ad7173_device_info ad4116_device_info = {
 	.name = "ad4116",
 	.id = AD4116_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in_div = 11,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -893,7 +910,7 @@ static const struct ad7173_device_info ad4116_device_info = {
 static const struct ad7173_device_info ad7172_2_device_info = {
 	.name = "ad7172-2",
 	.id = AD7172_2_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_4_slots,
 	.num_voltage_in = 5,
 	.num_channels = 4,
 	.num_configs = 4,
@@ -926,7 +943,7 @@ static const struct ad7173_device_info ad7172_4_device_info = {
 static const struct ad7173_device_info ad7173_8_device_info = {
 	.name = "ad7173-8",
 	.id = AD7173_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in = 17,
 	.num_channels = 16,
 	.num_configs = 8,
@@ -943,7 +960,7 @@ static const struct ad7173_device_info ad7173_8_device_info = {
 static const struct ad7173_device_info ad7175_2_device_info = {
 	.name = "ad7175-2",
 	.id = AD7175_2_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_4_slots,
 	.num_voltage_in = 5,
 	.num_channels = 4,
 	.num_configs = 4,
@@ -960,7 +977,7 @@ static const struct ad7173_device_info ad7175_2_device_info = {
 static const struct ad7173_device_info ad7175_8_device_info = {
 	.name = "ad7175-8",
 	.id = AD7175_8_ID,
-	.sd_info = &ad7173_sigma_delta_info_8_slots,
+	.sd_info = &ad7173_sigma_delta_info_16_slots,
 	.num_voltage_in = 17,
 	.num_channels = 16,
 	.num_configs = 8,

---
base-commit: 6742eff60460e77158d4f1b233f17e0345c9e66a
change-id: 20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-b982206a20b1

Best regards,
-- 
David Lechner <dlechner@baylibre.com>

Re: [PATCH v2] iio: adc: ad7173: fix num_slots

[David Lechner]

On 7/4/25 11:21 AM, David Lechner wrote:
> Fix the num_slots value for most chips in the ad7173 driver. The correct
> value is the number of CHANNELx registers on the chip.
> 
> In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
> ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
> to be static const data instead of being dynamically populated during
> driver probe. However, there was an existing bug in commit 76a1e6a42802
> ("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
> set to the number of CONFIGx registers instead of the number of
> CHANNELx registers. This bug was partially propagated to the refactored
> code in that the 16-channel chips were only given 8 slots instead of
> 16 although we did managed to fix the 8-channel chips and one of the
> 4-channel chips in that commit. However, we botched two of the 4-channel
> chips and ended up incorrectly giving them 8 slots during the
> refactoring.
> 
> This patch fixes that mistake on the 4-channel chips and also
> corrects the 16-channel chips to have 16 slots.
> 
> Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
> Signed-off-by: David Lechner <dlechner@baylibre.com>
> ---
> Changes in v2:
> - Improve commit message.
> - Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
> ---
>  drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
>  1 file changed, 27 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
>  	.num_slots = 8,
>  };
>  
> +static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
> +	.set_channel = ad7173_set_channel,
> +	.append_status = ad7173_append_status,
> +	.disable_all = ad7173_disable_all,
> +	.disable_one = ad7173_disable_one,
> +	.set_mode = ad7173_set_mode,
> +	.has_registers = true,
> +	.has_named_irqs = true,

> +	.supports_spi_offload = true,

Well drat, I was too quick with the update and the bots [1] noticed that
this conflicts with the in-flight patch that added this field [2].

I guess we can drop this one line, but then the other patch will wait
until this fix makes its way back into the togreg/testing branches.

[1]: https://lore.kernel.org/linux-iio/202507050018.iWEJiG04-lkp@intel.com/
[2]: https://lore.kernel.org/linux-iio/20250701-iio-adc-ad7173-add-spi-offload-support-v3-12-42abb83e3dac@baylibre.com/

> +	.addr_shift = 0,
> +	.read_mask = BIT(6),
> +	.status_ch_mask = GENMASK(3, 0),
> +	.data_reg = AD7173_REG_DATA,
> +	.num_resetclks = 64,
> +	.num_slots = 16,
> +};
> +

Re: [PATCH v2] iio: adc: ad7173: fix num_slots

[Jonathan Cameron]

On Fri, 4 Jul 2025 12:04:04 -0500
David Lechner <dlechner@baylibre.com> wrote:

> On 7/4/25 11:21 AM, David Lechner wrote:
> > Fix the num_slots value for most chips in the ad7173 driver. The correct
> > value is the number of CHANNELx registers on the chip.
> > 
> > In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
> > ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
> > to be static const data instead of being dynamically populated during
> > driver probe. However, there was an existing bug in commit 76a1e6a42802
> > ("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
> > set to the number of CONFIGx registers instead of the number of
> > CHANNELx registers. This bug was partially propagated to the refactored
> > code in that the 16-channel chips were only given 8 slots instead of
> > 16 although we did managed to fix the 8-channel chips and one of the
> > 4-channel chips in that commit. However, we botched two of the 4-channel
> > chips and ended up incorrectly giving them 8 slots during the
> > refactoring.
> > 
> > This patch fixes that mistake on the 4-channel chips and also
> > corrects the 16-channel chips to have 16 slots.
> > 
> > Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
> > Signed-off-by: David Lechner <dlechner@baylibre.com>
> > ---
> > Changes in v2:
> > - Improve commit message.
> > - Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
> > ---
> >  drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
> >  1 file changed, 27 insertions(+), 10 deletions(-)
> > 
> > diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> > index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
> > --- a/drivers/iio/adc/ad7173.c
> > +++ b/drivers/iio/adc/ad7173.c
> > @@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
> >  	.num_slots = 8,
> >  };
> >  
> > +static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
> > +	.set_channel = ad7173_set_channel,
> > +	.append_status = ad7173_append_status,
> > +	.disable_all = ad7173_disable_all,
> > +	.disable_one = ad7173_disable_one,
> > +	.set_mode = ad7173_set_mode,
> > +	.has_registers = true,
> > +	.has_named_irqs = true,  
> 
> > +	.supports_spi_offload = true,  
> 
> Well drat, I was too quick with the update and the bots [1] noticed that
> this conflicts with the in-flight patch that added this field [2].
> 
> I guess we can drop this one line, but then the other patch will wait
> until this fix makes its way back into the togreg/testing branches.

I'm lost - what would you prefer we do here?  For now I have [2] on my
tree but can drop just that one patch if it unwinds this complexity.
> 
> [1]: https://lore.kernel.org/linux-iio/202507050018.iWEJiG04-lkp@intel.com/
> [2]: https://lore.kernel.org/linux-iio/20250701-iio-adc-ad7173-add-spi-offload-support-v3-12-42abb83e3dac@baylibre.com/
> 
> > +	.addr_shift = 0,
> > +	.read_mask = BIT(6),
> > +	.status_ch_mask = GENMASK(3, 0),
> > +	.data_reg = AD7173_REG_DATA,
> > +	.num_resetclks = 64,
> > +	.num_slots = 16,
> > +};
> > +  
> 

Re: [PATCH v2] iio: adc: ad7173: fix num_slots

[David Lechner]

On 7/6/25 5:15 AM, Jonathan Cameron wrote:
> On Fri, 4 Jul 2025 12:04:04 -0500
> David Lechner <dlechner@baylibre.com> wrote:
> 
>> On 7/4/25 11:21 AM, David Lechner wrote:
>>> Fix the num_slots value for most chips in the ad7173 driver. The correct
>>> value is the number of CHANNELx registers on the chip.
>>>
>>> In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
>>> ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
>>> to be static const data instead of being dynamically populated during
>>> driver probe. However, there was an existing bug in commit 76a1e6a42802
>>> ("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
>>> set to the number of CONFIGx registers instead of the number of
>>> CHANNELx registers. This bug was partially propagated to the refactored
>>> code in that the 16-channel chips were only given 8 slots instead of
>>> 16 although we did managed to fix the 8-channel chips and one of the
>>> 4-channel chips in that commit. However, we botched two of the 4-channel
>>> chips and ended up incorrectly giving them 8 slots during the
>>> refactoring.
>>>
>>> This patch fixes that mistake on the 4-channel chips and also
>>> corrects the 16-channel chips to have 16 slots.
>>>
>>> Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
>>> Signed-off-by: David Lechner <dlechner@baylibre.com>
>>> ---
>>> Changes in v2:
>>> - Improve commit message.
>>> - Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
>>> ---
>>>  drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
>>>  1 file changed, 27 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
>>> index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
>>> --- a/drivers/iio/adc/ad7173.c
>>> +++ b/drivers/iio/adc/ad7173.c
>>> @@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
>>>  	.num_slots = 8,
>>>  };
>>>  
>>> +static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
>>> +	.set_channel = ad7173_set_channel,
>>> +	.append_status = ad7173_append_status,
>>> +	.disable_all = ad7173_disable_all,
>>> +	.disable_one = ad7173_disable_one,
>>> +	.set_mode = ad7173_set_mode,
>>> +	.has_registers = true,
>>> +	.has_named_irqs = true,  
>>
>>> +	.supports_spi_offload = true,  
>>
>> Well drat, I was too quick with the update and the bots [1] noticed that
>> this conflicts with the in-flight patch that added this field [2].
>>
>> I guess we can drop this one line, but then the other patch will wait
>> until this fix makes its way back into the togreg/testing branches.
> 
> I'm lost - what would you prefer we do here?  For now I have [2] on my
> tree but can drop just that one patch if it unwinds this complexity.

I was hoping you would tell me. :-p

In any case, we should apply this patch, with the supports_spi_offload
line dropped, first so that it backports cleanly to the stable release(s).

But where to apply this patch depends on if you are planning on doing
another fixes-togreg this release cycle or not. Or we could just opt
to take the slow path to avoid the dependency dance and just apply
both patches to iio/togreg and let it make it's way to stable after
the next merge cycle.

>>
>> [1]: https://lore.kernel.org/linux-iio/202507050018.iWEJiG04-lkp@intel.com/
>> [2]: https://lore.kernel.org/linux-iio/20250701-iio-adc-ad7173-add-spi-offload-support-v3-12-42abb83e3dac@baylibre.com/
>>
>>> +	.addr_shift = 0,
>>> +	.read_mask = BIT(6),
>>> +	.status_ch_mask = GENMASK(3, 0),
>>> +	.data_reg = AD7173_REG_DATA,
>>> +	.num_resetclks = 64,
>>> +	.num_slots = 16,
>>> +};
>>> +  
>>
> 

Re: [PATCH v2] iio: adc: ad7173: fix num_slots

[Jonathan Cameron]

On Sun, 6 Jul 2025 11:08:06 -0500
David Lechner <dlechner@baylibre.com> wrote:

> On 7/6/25 5:15 AM, Jonathan Cameron wrote:
> > On Fri, 4 Jul 2025 12:04:04 -0500
> > David Lechner <dlechner@baylibre.com> wrote:
> >   
> >> On 7/4/25 11:21 AM, David Lechner wrote:  
> >>> Fix the num_slots value for most chips in the ad7173 driver. The correct
> >>> value is the number of CHANNELx registers on the chip.
> >>>
> >>> In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
> >>> ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
> >>> to be static const data instead of being dynamically populated during
> >>> driver probe. However, there was an existing bug in commit 76a1e6a42802
> >>> ("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
> >>> set to the number of CONFIGx registers instead of the number of
> >>> CHANNELx registers. This bug was partially propagated to the refactored
> >>> code in that the 16-channel chips were only given 8 slots instead of
> >>> 16 although we did managed to fix the 8-channel chips and one of the
> >>> 4-channel chips in that commit. However, we botched two of the 4-channel
> >>> chips and ended up incorrectly giving them 8 slots during the
> >>> refactoring.
> >>>
> >>> This patch fixes that mistake on the 4-channel chips and also
> >>> corrects the 16-channel chips to have 16 slots.
> >>>
> >>> Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
> >>> Signed-off-by: David Lechner <dlechner@baylibre.com>
> >>> ---
> >>> Changes in v2:
> >>> - Improve commit message.
> >>> - Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
> >>> ---
> >>>  drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
> >>>  1 file changed, 27 insertions(+), 10 deletions(-)
> >>>
> >>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> >>> index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
> >>> --- a/drivers/iio/adc/ad7173.c
> >>> +++ b/drivers/iio/adc/ad7173.c
> >>> @@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
> >>>  	.num_slots = 8,
> >>>  };
> >>>  
> >>> +static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
> >>> +	.set_channel = ad7173_set_channel,
> >>> +	.append_status = ad7173_append_status,
> >>> +	.disable_all = ad7173_disable_all,
> >>> +	.disable_one = ad7173_disable_one,
> >>> +	.set_mode = ad7173_set_mode,
> >>> +	.has_registers = true,
> >>> +	.has_named_irqs = true,    
> >>  
> >>> +	.supports_spi_offload = true,    
> >>
> >> Well drat, I was too quick with the update and the bots [1] noticed that
> >> this conflicts with the in-flight patch that added this field [2].
> >>
> >> I guess we can drop this one line, but then the other patch will wait
> >> until this fix makes its way back into the togreg/testing branches.  
> > 
> > I'm lost - what would you prefer we do here?  For now I have [2] on my
> > tree but can drop just that one patch if it unwinds this complexity.  
> 
> I was hoping you would tell me. :-p
> 
> In any case, we should apply this patch, with the supports_spi_offload
> line dropped, first so that it backports cleanly to the stable release(s).
> 
> But where to apply this patch depends on if you are planning on doing
> another fixes-togreg this release cycle or not. Or we could just opt
> to take the slow path to avoid the dependency dance and just apply
> both patches to iio/togreg and let it make it's way to stable after
> the next merge cycle.

I'll almost certainly do another fixes pull, but it might not get into upstream
of my togreg branch fast enough. 

For now is just dropping patch 12 from the main series enough to avoid the
conflict?  If so send me a clean version of this and I'll apply that to the
fixes-togreg branch and we can hopefully get a round trip to pick up patch 12
on top of it.

Thanks,

Jonathan

> 
> >>
> >> [1]: https://lore.kernel.org/linux-iio/202507050018.iWEJiG04-lkp@intel.com/
> >> [2]: https://lore.kernel.org/linux-iio/20250701-iio-adc-ad7173-add-spi-offload-support-v3-12-42abb83e3dac@baylibre.com/
> >>  
> >>> +	.addr_shift = 0,
> >>> +	.read_mask = BIT(6),
> >>> +	.status_ch_mask = GENMASK(3, 0),
> >>> +	.data_reg = AD7173_REG_DATA,
> >>> +	.num_resetclks = 64,
> >>> +	.num_slots = 16,
> >>> +};
> >>> +    
> >>  
> >   
> 

Re: [PATCH v2] iio: adc: ad7173: fix num_slots

[David Lechner]

On 7/6/25 11:57 AM, Jonathan Cameron wrote:
> On Sun, 6 Jul 2025 11:08:06 -0500
> David Lechner <dlechner@baylibre.com> wrote:
> 
>> On 7/6/25 5:15 AM, Jonathan Cameron wrote:
>>> On Fri, 4 Jul 2025 12:04:04 -0500
>>> David Lechner <dlechner@baylibre.com> wrote:
>>>   
>>>> On 7/4/25 11:21 AM, David Lechner wrote:  
>>>>> Fix the num_slots value for most chips in the ad7173 driver. The correct
>>>>> value is the number of CHANNELx registers on the chip.
>>>>>
>>>>> In commit 4310e15b3140 ("iio: adc: ad7173: don't make copy of
>>>>> ad_sigma_delta_info struct"), we refactored struct ad_sigma_delta_info
>>>>> to be static const data instead of being dynamically populated during
>>>>> driver probe. However, there was an existing bug in commit 76a1e6a42802
>>>>> ("iio: adc: ad7173: add AD7173 driver") where num_slots was incorrectly
>>>>> set to the number of CONFIGx registers instead of the number of
>>>>> CHANNELx registers. This bug was partially propagated to the refactored
>>>>> code in that the 16-channel chips were only given 8 slots instead of
>>>>> 16 although we did managed to fix the 8-channel chips and one of the
>>>>> 4-channel chips in that commit. However, we botched two of the 4-channel
>>>>> chips and ended up incorrectly giving them 8 slots during the
>>>>> refactoring.
>>>>>
>>>>> This patch fixes that mistake on the 4-channel chips and also
>>>>> corrects the 16-channel chips to have 16 slots.
>>>>>
>>>>> Fixes: 4310e15b3140 ("iio: adc: ad7173: don't make copy of ad_sigma_delta_info struct")
>>>>> Signed-off-by: David Lechner <dlechner@baylibre.com>
>>>>> ---
>>>>> Changes in v2:
>>>>> - Improve commit message.
>>>>> - Link to v1: https://lore.kernel.org/r/20250703-iio-adc-ad7173-fix-num_slots-on-most-chips-v1-1-326c5d113e15@baylibre.com
>>>>> ---
>>>>>  drivers/iio/adc/ad7173.c | 37 +++++++++++++++++++++++++++----------
>>>>>  1 file changed, 27 insertions(+), 10 deletions(-)
>>>>>
>>>>> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
>>>>> index dd9fa35555c79ead5a1b88d1dc6cc3db122502be..9c197cea11eb955becf4b9b97246379fa9c5da13 100644
>>>>> --- a/drivers/iio/adc/ad7173.c
>>>>> +++ b/drivers/iio/adc/ad7173.c
>>>>> @@ -771,10 +771,27 @@ static const struct ad_sigma_delta_info ad7173_sigma_delta_info_8_slots = {
>>>>>  	.num_slots = 8,
>>>>>  };
>>>>>  
>>>>> +static const struct ad_sigma_delta_info ad7173_sigma_delta_info_16_slots = {
>>>>> +	.set_channel = ad7173_set_channel,
>>>>> +	.append_status = ad7173_append_status,
>>>>> +	.disable_all = ad7173_disable_all,
>>>>> +	.disable_one = ad7173_disable_one,
>>>>> +	.set_mode = ad7173_set_mode,
>>>>> +	.has_registers = true,
>>>>> +	.has_named_irqs = true,    
>>>>  
>>>>> +	.supports_spi_offload = true,    
>>>>
>>>> Well drat, I was too quick with the update and the bots [1] noticed that
>>>> this conflicts with the in-flight patch that added this field [2].
>>>>
>>>> I guess we can drop this one line, but then the other patch will wait
>>>> until this fix makes its way back into the togreg/testing branches.  
>>>
>>> I'm lost - what would you prefer we do here?  For now I have [2] on my
>>> tree but can drop just that one patch if it unwinds this complexity.  
>>
>> I was hoping you would tell me. :-p
>>
>> In any case, we should apply this patch, with the supports_spi_offload
>> line dropped, first so that it backports cleanly to the stable release(s).
>>
>> But where to apply this patch depends on if you are planning on doing
>> another fixes-togreg this release cycle or not. Or we could just opt
>> to take the slow path to avoid the dependency dance and just apply
>> both patches to iio/togreg and let it make it's way to stable after
>> the next merge cycle.
> 
> I'll almost certainly do another fixes pull, but it might not get into upstream
> of my togreg branch fast enough. 
> 
> For now is just dropping patch 12 from the main series enough to avoid the
> conflict?  If so send me a clean version of this and I'll apply that to the
> fixes-togreg branch and we can hopefully get a round trip to pick up patch 12
> on top of it.

Yes. Drop patch 12 and I will send a new version of both patches. This
one can be applied to fixes and the other can wait.

> 
> Thanks,
> 
> Jonathan
> 
>>
>>>>
>>>> [1]: https://lore.kernel.org/linux-iio/202507050018.iWEJiG04-lkp@intel.com/
>>>> [2]: https://lore.kernel.org/linux-iio/20250701-iio-adc-ad7173-add-spi-offload-support-v3-12-42abb83e3dac@baylibre.com/
>>>>  
>>>>> +	.addr_shift = 0,
>>>>> +	.read_mask = BIT(6),
>>>>> +	.status_ch_mask = GENMASK(3, 0),
>>>>> +	.data_reg = AD7173_REG_DATA,
>>>>> +	.num_resetclks = 64,
>>>>> +	.num_slots = 16,
>>>>> +};
>>>>> +    
>>>>  
>>>   
>>
>