Re: [PATCH v8 10/16] reset: Add a reset controller driver for the Lantiq XWAY based SoCs

Hauke Mehrtens
2017-08-03T21:41:57Z

On 08/03/2017 10:33 AM, Philipp Zabel wrote:
> Hi Hauke,
>
> On Thu, 2017-08-03 at 00:57 +0200, Hauke Mehrtens wrote:
>> From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
>>
>> The reset controllers (on xRX200 and newer SoCs have two of them) are
>> provided by the RCU module. This was initially implemented as a simple
>> reset controller. However, the RCU module provides more functionality
>> (ethernet GPHYs, USB PHY, etc.), which makes it a MFD device.
>> The old reset controller driver implementation from
>> arch/mips/lantiq/xway/reset.c did not honor this fact.
>>
>> For some devices the request and the status bits are different.
>>
>> Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
>> Cc: Philipp Zabel <p.zabel@pengutronix.de>
>> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
>> ---
>> .../devicetree/bindings/reset/lantiq,reset.txt | 30 +++
>> drivers/reset/Kconfig | 6 +
>> drivers/reset/Makefile | 1 +
>> drivers/reset/reset-lantiq.c | 224 +++++++++++++++++++++
>> 4 files changed, 261 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/reset/lantiq,reset.txt
>> create mode 100644 drivers/reset/reset-lantiq.c
>>
> [...]
>> diff --git a/drivers/reset/reset-lantiq.c b/drivers/reset/reset-lantiq.c
>> new file mode 100644
>> index 000000000000..b84c45e7e6b8
>> --- /dev/null
>> +++ b/drivers/reset/reset-lantiq.c
>> @@ -0,0 +1,224 @@
> [...]
>> +static int lantiq_rcu_reset_of_probe(struct platform_device *pdev,
>> + struct lantiq_rcu_reset_priv *priv)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct resource *res;
>> + struct resource res_parent;
>> + int ret;
>> +
>> + priv->regmap = syscon_node_to_regmap(dev->of_node->parent);
>> + if (IS_ERR(priv->regmap)) {
>> + dev_err(&pdev->dev, "Failed to lookup RCU regmap\n");
>> + return PTR_ERR(priv->regmap);
>> + }
>> +
>> + ret = of_address_to_resource(dev->of_node->parent, 0, &res_parent);
>> + if (ret)
>> + return ret;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + if (!res) {
>> + dev_err(&pdev->dev, "Failed to get RCU reset offset\n");
>> + return ret;
>
> This should return -EINVAL instead of 0.

I will fix this in the next round, I am still waiting for Rob's feedback.

The same problem exists in the USB PHY driver, I will also fix it there.

>
>> + }
>> +
>> + if (res->start < res_parent.start)
>> + return -ENOENT;
>> + priv->reset_offset = res->start - res_parent.start;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>> + if (!res) {
>> + dev_err(&pdev->dev, "Failed to get RCU status offset\n");
>> + return ret;
>
> Same here.
>
> With this fixed,
> Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
>
> regards
> Philipp
>

Hauke