Re: [PATCH v4 3/3] iio: adc: add support for Allwinner SoCs ADC

From: Quentin Schulz
Date: Mon Sep 05 2016 - 02:29:31 EST


On 04/09/2016 16:35, Jonathan Cameron wrote:
> On 01/09/16 15:05, Quentin Schulz wrote:
>> The Allwinner SoCs all have an ADC that can also act as a touchscreen
>> controller and a thermal sensor. This patch adds the ADC driver which is
>> based on the MFD for the same SoCs ADC.
>>
>> This also registers the thermal adc channel in the iio map array so
>> iio_hwmon could use it without modifying the Device Tree. This registers
>> the driver in the thermal framework.
>>
>> This driver probes on three different platform_device_id to take into
>> account slight differences (registers bit and temperature computation)
>> between Allwinner SoCs ADCs.
>>
>> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
> One utterly trivial point about unrolling code ordering inline.
>
> Other than the bit about patch 1 I'm basically happy with this..

ACK. Will revert this patch in v5. Thanks.

> However I would like some input (i.e. an Ack) from thermal given this
> sets up a thermal zone.
>
> Zhang or Eduardo, could you take a quick look at this and confirm you
> are happy with it?
>
> Thanks,
>
> Jonathan
[...]
>> +
>> +err_map:
>> + iio_map_array_unregister(indio_dev);
>> +
>> +err_fifo_irq:
>> + /* Disable FIFO_DATA_PENDING interrupt on hardware side. */
>> + regmap_update_bits(info->regmap, SUN4I_GPADC_INT_FIFOC,
>> + SUN4I_GPADC_INT_FIFOC_TP_DATA_IRQ_EN,
>> + 0);
>> +
>> +err_temp_irq:
>> + /* Disable TEMP_DATA_PENDING interrupt on hardware side. */
>> + regmap_update_bits(info->regmap, SUN4I_GPADC_INT_FIFOC,
>> + SUN4I_GPADC_INT_FIFOC_TEMP_IRQ_EN,
>> + 0);
>> +
>> +err:
>> + pm_runtime_put(&pdev->dev);
>> + pm_runtime_disable(&pdev->dev);
>> +
>> + return ret;
>> +}
>> +
>> +static int sun4i_gpadc_remove(struct platform_device *pdev)
>> +{
>> + struct sun4i_gpadc_dev *info;
>> + struct iio_dev *indio_dev = platform_get_drvdata(pdev);
>> +
>> + info = iio_priv(indio_dev);
>> + iio_device_unregister(indio_dev);
>> + iio_map_array_unregister(indio_dev);
>> + pm_runtime_put(&pdev->dev);
>> + pm_runtime_disable(&pdev->dev);
> Its really minor but in the interests of 'obviously correct' making
> review easy I'd rather everything in the remove was in the reverse order
> of probe (and hence the same as the error path in probe for most of it).
>
> That would put the pm_runtime stuff last I think..
>
> If you weren't rerolling anyway over patch 1 I'd probably have just let
> this go, but might as well make this trivial change as well.
>

I'm going with the following order:
pm_runtime_put
pm_runtime_disable
regmap_update_bits
iio_map_array_unregister
iio_device_unregister

Is that okay? (I don't really know which one of iio_map_array_unregister
or iio_device_unregister to put first, if it matters in any way).

Thanks!
Quentin
>
>> + /*
>> + * Disable TEMP_DATA_PENDING and FIFO_DATA_PENDING interrupts on
>> + * hardware side.
>> + */
>> + regmap_update_bits(info->regmap, SUN4I_GPADC_INT_FIFOC,
>> + SUN4I_GPADC_INT_FIFOC_TEMP_IRQ_EN |
>> + SUN4I_GPADC_INT_FIFOC_TP_DATA_IRQ_EN,
>> + 0);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct platform_device_id sun4i_gpadc_id[] = {
>> + { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_soc_specific },
>> + { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_soc_specific },
>> + { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_soc_specific },
>> + { /* sentinel */ },
>> +};
>> +
>> +static struct platform_driver sun4i_gpadc_driver = {
>> + .driver = {
>> + .name = "sun4i-gpadc-iio",
>> + .pm = &sun4i_gpadc_pm_ops,
>> + },
>> + .id_table = sun4i_gpadc_id,
>> + .probe = sun4i_gpadc_probe,
>> + .remove = sun4i_gpadc_remove,
>> +};
>> +
>> +module_platform_driver(sun4i_gpadc_driver);
>> +
>> +MODULE_DESCRIPTION("ADC driver for sunxi platforms");
>> +MODULE_AUTHOR("Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>");
>> +MODULE_LICENSE("GPL v2");
>>
>