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

[Kishon Vijay Abraham I <kishon@ti.com>]

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?

Cheers
Kishon