Re: [PATCH 2/2] iio: adc: exynos_adc: Add support for S3C24xx ADC

Chanwoo Choi
2014-07-28T11:20:20Z

On 07/22/2014 05:39 PM, Arnd Bergmann wrote:
> On Tuesday 22 July 2014 11:11:14 Chanwoo Choi wrote:
>> This patch add support for s3c2410/s3c2416/s3c2440/s3c2443 ADC. The s3c24xx
>> is alomost same as ADCv1. But, There are a little difference as following:
>> - ADCMUX register address to select channel
>> - ADCDAT mask (10bit or 12bit ADC resolution according to SoC version)
>
> Very good, thanks for doing this patch!
>
> (adding Heiko to Cc, he's probably interested in seeing this as well.
>
> One comment:
>
>> @@ -101,12 +107,14 @@ struct exynos_adc {
>> struct completion completion;
>>
>> u32 value;
>> + u32 value2;
>> unsigned int version;
>> };
>> ...
>> @@ -365,7 +448,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
>> ret = -ETIMEDOUT;
>> } else {
>> *val = info->value;
>> - *val2 = 0;
>> + *val2 = info->value2;
>> ret = IIO_VAL_INT;
>> }
>>
>> @@ -377,9 +460,11 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
>> static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
>> {
>> struct exynos_adc *info = (struct exynos_adc *)dev_id;
>> + u32 mask = info->data->mask;
>>
>> /* Read value */
>> - info->value = readl(ADC_V1_DATX(info->regs)) & ADC_DATX_MASK;
>> + info->value = readl(ADC_V1_DATX(info->regs)) & mask;
>> + info->value2 = readl(ADC_V1_DATY(info->regs)) & mask;
>>
>> /* clear irq */
>> if (info->data->clear_irq)
>
> If I understand it right, this would only be necessary if we want
> to do the touchscreen driver as a separate iio client using the
> in-kernel interfaces. As Jonathan Cameron commented, we probably
> don't want to do that though. Even if we do, it should be a separate
> patch and not mixed in with the s3c24xx support.

OK, I'll drop this sentence which reading DATY register.

Best Regards,
Chanwoo Choi

>
> Aside from this:
>
> Acked-by: Arnd Bergmann <arnd@arndb.de>
>
> Arnd
>