Re: [PATCH 1/3] phy: omap-usb2: Manage PHY 3.3V supply regulator

Roger Quadros
2014-07-01T10:26:01Z

On 07/01/2014 01:20 PM, Kishon Vijay Abraham I wrote:
> Hi,
>
> On Tuesday 01 July 2014 03:43 PM, Roger Quadros wrote:
>> On 07/01/2014 12:56 PM, Kishon Vijay Abraham I wrote:
>>> Hi Roger,
>>>
>>> On Monday 30 June 2014 04:30 PM, Roger Quadros wrote:
>>>> On some SoCs e.g. J6 the 3.3V supply to the USB2 PHY can be
>>>> powered down when the PHY is not in use. Add regulator
>>>> management code to control this power line.
>>>>
>>>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>>>> ---
>>>> drivers/phy/phy-omap-usb2.c | 25 +++++++++++++++++++++++++
>>>> include/linux/phy/omap_usb.h | 1 +
>>>> 2 files changed, 26 insertions(+)
>>>>
>>>> diff --git a/drivers/phy/phy-omap-usb2.c b/drivers/phy/phy-omap-usb2.c
>>>> index 7007c11..2afc79c 100644
>>>> --- a/drivers/phy/phy-omap-usb2.c
>>>> +++ b/drivers/phy/phy-omap-usb2.c
>>>> @@ -30,6 +30,7 @@
>>>> #include <linux/phy/omap_control_phy.h>
>>>> #include <linux/phy/phy.h>
>>>> #include <linux/of_platform.h>
>>>> +#include <linux/regulator/consumer.h>
>>>>
>>>> #define USB2PHY_DISCON_BYP_LATCH (1 << 31)
>>>> #define USB2PHY_ANA_CONFIG1 0x4c
>>>> @@ -107,6 +108,14 @@ static int omap_usb_power_off(struct phy *x)
>>>>
>>>> omap_control_phy_power(phy->control_dev, 0);
>>>>
>>>> + if (phy->pwr) {
>>>> + int ret;
>>>> +
>>>> + ret = regulator_disable(phy->pwr);
>>>> + if (ret)
>>>> + return ret;
>>>> + }
>>>> +
>>>> return 0;
>>>> }
>>>>
>>>> @@ -114,6 +123,14 @@ static int omap_usb_power_on(struct phy *x)
>>>> {
>>>> struct omap_usb *phy = phy_get_drvdata(x);
>>>>
>>>> + if (phy->pwr) {
>>>> + int ret;
>>>> +
>>>> + ret = regulator_enable(phy->pwr);
>>>> + if (ret)
>>>> + return ret;
>>>> + }
>>>> +
>>>
>>> Shouldn't we do this in phy_power_on/phy_power_off in phy-core?
>>
>> I thought about that earlier, but could not find a way to defer probing if the regulator is not-yet probed.
>> Any clues how it could be done in phy-core?
>
> We can try to do regulator_get in phy_create and return EPROBE_DEFER if the
> regulator_get returns EPROBE_DEFER no?

Yes indeed, we can. I missed the phy_create() and was only looking at phy_init() and phy_power_*() :P.
I'll post a v2 soon.

cheers,
-roger