Re: [PATCH] serial driver PMC MSP71xx, kernel linux-mips.git mast er

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello.

Marc St-Jean wrote:

> > > Fourth attempt at the serial driver patch for the PMC-Sierra MSP71xx 
> > device.

> > > There are three different fixes:
> > > 1. Fix for DesignWare THRE errata
> > > - Dropped our fix since the "8250-uart-backup-timer.patch" in the "mm"
> > > tree also fixes it. This patch needs to be applied on top of "mm" patch.

   I think you need to submit your patch to Andrew Morton since it requires a 
patch from his tree.

> > > @@ -1383,6 +1399,19 @@ static irqreturn_t serial8250_interrupt(
> > >                       handled = 1;
> > >
> > >                       end = NULL;
> > > +             } else if (up->port.iotype == UPIO_DWAPB &&
> > > +                             (iir & UART_IIR_BUSY) == UART_IIR_BUSY) {

> >     Worth aligning this line with the opening paren of if... but's that's
> > nitpicking. :-)

> No problem I'll change it. I just usually align to the closest tab stop to
> the opening parenthesis.

   It haven't really changed in the last patch. :-)

> > > +                     /* The DesignWare APB UART has an Busy Detect 
> > (0x07)
> > > +                      * interrupt meaning an LCR write attempt 
> > occured while the
> > > +                      * UART was busy. The interrupt must be cleared 
> > by reading
> > > +                      * the UART status register (USR) and the LCR 
> > re-written. */
> > > +                     unsigned int status;
> > > +                     status = *(volatile u32 *)up->port.private_data;
> > > +                     serial_out(up, UART_LCR, up->lcr);
> > > +
> > > +                     handled = 1;
> > > +
> > > +                     end = NULL;
> > >               } else if (end == NULL)
> > >                       end = l;
> > >
> > >       return 0;

> >    Still, shouldn't you be doing this in serial8250_timeout()

> No, the serial8250_timeout is for issue 1 at the top, this is for
> issue 2.

   It's for lost interrupts, IIUC. They use anothe timeout handler for the 
workaround...

> > also?
> > What IRQ numbers this UART is using, BTW?

> For the ports on the device they are 27 and 42. Is there any significance
> that I'm not aware of?

   Yeah, IRQ0 is treated as no IRQ by 8250, and in this case it falls back to 
using serial8250_timeout() to handle "interrupts".

> > > diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
> > > index cf23813..bd9711a 100644
> > > --- a/include/linux/serial_core.h
> > > +++ b/include/linux/serial_core.h
> > > @@ -276,6 +277,7 @@ #define UPF_USR_MASK              ((__force upf_t) (
> > >       struct device           *dev;                   /* parent 
> > device */
> > >       unsigned char           hub6;                   /* this should 
> > be in the 8250 driver */
> > >       unsigned char           unused[3];
> > > +     void                            *private_data;          /* 
> > generic platform data pointer */

> >    One tab to many before *private_data...

> In my editor using 4 columns per tab it lines up with everything. Is there
> some convention that patches should be made assuming 8 columns?

   Documentation/CodingStyle, chapter 1. :-)

> >    Oops, your mailer went and did it again. :-)

> I'm completely giving up on Thunderbird,unless someone can point out

   Ypu should have long ago. :-)

> the specific internal configuration items which needs a kick!

   Only the attachments will work in the Mozilla kind mailer, AFAIK.
The last patch looked OK at last. :-)

> Thanks,
> Marc

WBR, Sergei
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