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

Michael Grzeschik mgr at pengutronix.de
Wed Nov 21 10:57:23 EST 2012


On Fri, Nov 16, 2012 at 05:39:42PM +0200, Alexander Shishkin wrote:
> 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.

To handle lpm devices in this patch, we need some register layout of the
lpm core. Probably only te DEVLC register. Is there some documentation
available?

Regards,
Michael

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |



More information about the linux-arm-kernel mailing list