On 2016?07?26? 17:00, John Keeping wrote:
> On Tue, 26 Jul 2016 14:11:47 +0800, Caesar Wang wrote:
>
>> SARADC controller needs to be reset before programming it, otherwise
>> it will not function properly.
>>
>> Signed-off-by: Caesar Wang <wxt at rock-chips.com>
>> Cc: Jonathan Cameron <jic23 at kernel.org>
>> Cc: Heiko Stuebner <heiko at sntech.de>
>> Cc: Rob Herring <robh+dt at kernel.org>
>> Cc: linux-iio at vger.kernel.org
>> Cc: linux-rockchip at lists.infradead.org
>> ---
>>
>> diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
>> index f9ad6c2..2f0e110 100644
>> --- a/drivers/iio/adc/rockchip_saradc.c
>> +++ b/drivers/iio/adc/rockchip_saradc.c
>> @@ -218,6 +231,13 @@ static int rockchip_saradc_probe(struct platform_device *pdev)
>> if (IS_ERR(info->regs))
>> return PTR_ERR(info->regs);
>>
>> + info->reset = devm_reset_control_get(&pdev->dev, "saradc-apb");
>> + if (IS_ERR(info->reset)) {
>> + ret = PTR_ERR(info->reset);
>> + dev_err(&pdev->dev, "failed to get saradc reset: %d\n", ret);
>> + return ret;
>> + }
> Does this need to handle ENOENT so as to avoid failing with old device
> tree blobs?
I'm no sure why we have to support the old device tree,
We can apply this series patches if we need to support the reset property.
---
Maybe, I can follow you suggestion to handle the ENOENT, as following:
+ /*
+ * The reset should be an optional property, as it should work
+ * with old devicetrees as well
+ */
+ info->reset = devm_reset_control_get(&pdev->dev, "saradc-apb");
+ if (IS_ERR(info->reset)) {
+ if (PTR_ERR(info->reset) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ return ret;
+ }
+ dev_dbg(&pdev->dev, "no reset control found\n");
+ info->reset = NULL;
+ }
...
+ if (info->reset)
+ rockchip_saradc_reset_controller(info->reset);
+
How about it?
-
Caesar
>
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--
caesar wang | software engineer | wxt at rock-chip.com
