Re: [PATCH] net: fec: add post PHY reset delay DT property

From: Quentin Schulz
Date: Mon May 22 2017 - 10:01:12 EST


Hi Andrew

On 22/05/2017 15:57, Andrew Lunn wrote:
> On Mon, May 22, 2017 at 11:15:17AM +0200, Quentin Schulz wrote:
>> Some PHY require to wait for a bit after the reset GPIO has been
>> toggled. This adds support for the DT property `phy-reset-post-delay`
>> which gives the delay in milliseconds to wait after reset.
>>
>> If the DT property is not given, no delay is observed. Post reset delay
>> greater than 1000ms are invalid and are default to 1ms.
>
> Hi Quentin
>
> If it is invalid, please return -EINVAL.
>

Just copying the wording and behavior of phy-reset-duration. Should we
then change the behavior of phy-reset-duration as well to return -EINVAL
in that case or I just leave both as is?

Quentin

>> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
>> ---
>> Documentation/devicetree/bindings/net/fsl-fec.txt | 5 +++++
>> drivers/net/ethernet/freescale/fec_main.c | 17 +++++++++++++++--
>> 2 files changed, 20 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/net/fsl-fec.txt b/Documentation/devicetree/bindings/net/fsl-fec.txt
>> index a1e3693cca16..8795e8ca5793 100644
>> --- a/Documentation/devicetree/bindings/net/fsl-fec.txt
>> +++ b/Documentation/devicetree/bindings/net/fsl-fec.txt
>> @@ -15,6 +15,11 @@ Optional properties:
>> - phy-reset-active-high : If present then the reset sequence using the GPIO
>> specified in the "phy-reset-gpios" property is reversed (H=reset state,
>> L=operation state).
>> +- phy-reset-post-delay : Post reset delay in milliseconds. If present then
>> + a delay of phy-reset-post-delay milliseconds will be observed after the
>> + phy-reset-gpios has been toggled. Can be omitted thus no delay is
>> + observed. Delay is in range of 1ms to 1000ms. If given delay is higher
>> + than 1000ms, 1ms delay is done instead.
>> - phy-supply : regulator that powers the Ethernet PHY.
>> - phy-handle : phandle to the PHY device connected to this device.
>> - fixed-link : Assume a fixed link. See fixed-link.txt in the same directory.
>> diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
>> index 56a563f90b0b..00a7fd0bcd59 100644
>> --- a/drivers/net/ethernet/freescale/fec_main.c
>> +++ b/drivers/net/ethernet/freescale/fec_main.c
>> @@ -3192,7 +3192,7 @@ static int fec_reset_phy(struct platform_device *pdev)
>> {
>> int err, phy_reset;
>> bool active_high = false;
>> - int msec = 1;
>> + int msec = 1, phy_post_delay = 0;
>> struct device_node *np = pdev->dev.of_node;
>>
>> if (!np)
>> @@ -3210,7 +3210,6 @@ static int fec_reset_phy(struct platform_device *pdev)
>> return 0;
>>
>> active_high = of_property_read_bool(np, "phy-reset-active-high");
>> -
>> err = devm_gpio_request_one(&pdev->dev, phy_reset,
>> active_high ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
>> "phy-reset");
>
> No white space changes please.
>
> Andrew
>

--
Quentin Schulz, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com