[PATCH 6/9] usb: chipidea: add PTW and PTS handling

Alexander Shishkin alexander.shishkin at linux.intel.com
Fri Nov 16 10:39:42 EST 2012


Matthieu CASTET <matthieu.castet at parrot.com> writes:

> Alexander Shishkin a écrit :
>> Michael Grzeschik <mgr at pengutronix.de> writes:
>> 
>>> On Fri, Nov 16, 2012 at 03:34:23PM +0200, Alexander Shishkin wrote:
>>>> Michael Grzeschik <mgr at pengutronix.de> writes:
>>>>
>>>>> On Fri, Nov 16, 2012 at 02:45:39PM +0200, Alexander Shishkin wrote:
>>>>>> Michael Grzeschik <m.grzeschik at pengutronix.de> writes:
>>>>>>
>>>>>>> This patch makes it possible to configure the PTW and PTS bits inside
>>>>>>> the portsc register for host and device mode before the driver starts
>>>>>>> and the phy can be addressed as hardware implementation is designed.
>>>>>>>
>>>>>>> Signed-off-by: Michael Grzeschik <m.grzeschik at pengutronix.de>
>>>>>>> Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
>>>>>>> ---
>>>>>>>  drivers/usb/chipidea/bits.h        |    3 +++
>>>>>>>  drivers/usb/chipidea/ci.h          |    2 ++
>>>>>>>  drivers/usb/chipidea/ci13xxx_imx.c |    1 +
>>>>>>>  drivers/usb/chipidea/core.c        |   47 ++++++++++++++++++++++++++++++++++++
>>>>>>>  drivers/usb/chipidea/host.c        |    4 +++
>>>>>>>  include/linux/usb/chipidea.h       |    9 +++++++
>>>>>>>  6 files changed, 66 insertions(+)
>>>>>>>
>>>>>>> diff --git a/drivers/usb/chipidea/bits.h b/drivers/usb/chipidea/bits.h
>>>>>>> index 4b6ae3e..3cded5f 100644
>>>>>>> --- a/drivers/usb/chipidea/bits.h
>>>>>>> +++ b/drivers/usb/chipidea/bits.h
>>>>>>> @@ -48,6 +48,9 @@
>>>>>>>  #define PORTSC_SUSP           BIT(7)
>>>>>>>  #define PORTSC_HSP            BIT(9)
>>>>>>>  #define PORTSC_PTC            (0x0FUL << 16)
>>>>>>> +#define PORTSC_PTS            (BIT(31) | BIT(30))
>>>>>>> +#define PORTSC_PTW            BIT(28)
>>>>>>> +#define PORTSC_STS            BIT(29)
>>>>>> Hm, my spec says these are actually in DEVLC register and only have this
>>>>>> meaning in device mode. And in portsc these bits fall in device address
>>>>>> bitfield. Can you refer me to your spec?
>>>>> You can find it here:
>>>>> http://cache.freescale.com/files/32bit/doc/ref_manual/iMX53RM.pdf?fpsp=1
>>>>> Page 4947
>>>> Oh, but see, the offset is 0x184, which in chipidea spec (the version
>>>> that I have) corresponds to DEVLC and not PORTSC. So in this driver's
>>>> terminology it's DEVLC too, at least currently.
>>>>
>>>> So have you tested this code and did it make any difference?
>>> Yes, i have tested this code with MX25, MX28, MX35 and MX53. In every
>>> SoCs Datasheet the PORTSC register is defined on PORTBASE+0x184. Without
>>> this proper configuration its not possible to communicate with the PHY.
>> 
>> No, I mean, you're writing DEVLC (using present driver's terminology)
>> bits to PORTSC register. It *shouldn't* work. I suppose, it does
>> something, but not exactly what you intended.
>> 
> I confirm in our datasheet we have PTW, PTS, STS in this register  PORTSCx with
> this mapping.
>
> In later design that support lpm, these bits have to move in another register
> because ehci 1.1 use them [1].

Ahh, I didn't realize imxes were nolpm. Now it makes more sense. This
means that, as you suggested in the other mail, these portsc/devlc
accesses should be done conditionally based on ci->hw_bank.lpm.

Regards,
--
Alex



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