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Message-ID: <ca18c346-94f3-4c4c-a540-57509b879b04@salutedevices.com>
Date:   Mon, 27 Nov 2023 22:17:33 +0300
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Subject: Re: [PATCH v2 1/1] iio: adc: meson: add separate config for axg SoC
 family
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To:     Jonathan Cameron <jic23@kernel.org>
CC:     <lars@metafoo.de>, <neil.armstrong@linaro.org>,
        <khilman@baylibre.com>, <jbrunet@baylibre.com>,
        <martin.blumenstingl@googlemail.com>,
        <andriy.shevchenko@linux.intel.com>, <nuno.sa@analog.com>,
        <u.kleine-koenig@pengutronix.de>, <linux-iio@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>,
        <linux-amlogic@lists.infradead.org>, <kernel@salutedevices.com>
References: <20231122074741.154228-1-gnstark@salutedevices.com>
 <20231125172508.2a2242bf@jic23-huawei>
From:   George Stark <gnstark@salutedevices.com>
In-Reply-To: <20231125172508.2a2242bf@jic23-huawei>
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Hello Jonathan

Thanks for the review.

On 11/25/23 20:25, Jonathan Cameron wrote:
> On Wed, 22 Nov 2023 10:47:41 +0300
> George Stark <gnstark@salutedevices.com> wrote:
> 
>> According to Amlogic custom kernels ADC of axg SoC family has
>> vref_select and requires this setting to work nominally and thus
>> needs a separate config.
>>
>> Signed-off-by: George Stark <gnstark@salutedevices.com>
>> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
> 
> Is this a fix?  If so, please provide a fixes tag.
Actually yes, these changes could be done in the patch that introduced
new configuration parameters.

> Or is it aligning with the vendor kernels and we don't know if
> it's strictly necessary or not?
I do know it's necessary if we want kernel driver to be independent from 
ADC initialization in vendor u-boot code. I have Amlogic a113x device 
(axg family) and can provide test results w and w/o this patch.

> 
>> ---
>>   drivers/iio/adc/meson_saradc.c | 16 +++++++++++++++-
>>   1 file changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
>> index db280da9edbf..34555a85f131 100644
>> --- a/drivers/iio/adc/meson_saradc.c
>> +++ b/drivers/iio/adc/meson_saradc.c
>> @@ -1242,6 +1242,20 @@ static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
>>   	.cmv_select = 1,
>>   };
>>   
>> +static const struct meson_sar_adc_param meson_sar_adc_axg_param = {
>> +	.has_bl30_integration = true,
>> +	.clock_rate = 1200000,
>> +	.bandgap_reg = MESON_SAR_ADC_REG11,
>> +	.regmap_config = &meson_sar_adc_regmap_config_gxbb,
>> +	.resolution = 12,
>> +	.disable_ring_counter = 1,
>> +	.has_reg11 = true,
>> +	.vref_volatge = 1,
>> +	.has_vref_select = true,
>> +	.vref_select = VREF_VDDA,
>> +	.cmv_select = 1,
>> +};
>> +
>>   static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
>>   	.has_bl30_integration = false,
>>   	.clock_rate = 1200000,
>> @@ -1286,7 +1300,7 @@ static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
>>   };
>>   
>>   static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
>> -	.param = &meson_sar_adc_gxl_param,
>> +	.param = &meson_sar_adc_axg_param,
>>   	.name = "meson-axg-saradc",
>>   };
>>   
> 

-- 
Best regards
George