Re: [PATCH] Revert "sdhci-of-esdhc: Support 8BIT bus width."

Kevin Hao
2015-05-17T05:04:30Z

[-- Attachment #1: Type: text/plain, Size: 2030 bytes --]

On Fri, May 15, 2015 at 07:49:29AM +0000, Joakim Tjernlund wrote:
> On Fri, 2015-05-15 at 15:36 +0800, Kevin Hao wrote:
> > On Fri, May 15, 2015 at 07:02:44AM +0000, Joakim Tjernlund wrote:
> > > Reverting this seem a bit to much. Looking in the log it seems commit
> > > 2317f56c055fcad524bf6a873df48a754e7ebc4d
> > > introduced the error by not checking for host->ops->set_bus_width before
> > > calling it.
> > >
> > > How does this work for you?
> >
> > No. My sd card still don't work with this change.
> >
> > >
> > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > > index c80287a..23603b2 100644
> > > --- a/drivers/mmc/host/sdhci.c
> > > +++ b/drivers/mmc/host/sdhci.c
> > > @@ -1528,7 +1528,10 @@ static void sdhci_do_set_ios(struct sdhci_host *host, struct mmc_ios *ios)
> > > if (host->ops->platform_send_init_74_clocks)
> > > host->ops->platform_send_init_74_clocks(host, ios->power_mode);
> > >
> > > - host->ops->set_bus_width(host, ios->bus_width);
> > > + if (host->ops->set_bus_width)
> > > + host->ops->set_bus_width(host, ios->bus_width);
> > > + else
> > > + sdhci_set_bus_width(host, ios->bus_width);
> >
> > The default sdhci_set_bus_width() doesn't apply to the esdhc controller on my
> > board (p2020rdb). This controller is compatible with the sd host specification
> > 2.0 and the implementation of sdhci_set_bus_width() can't set the bus width
> > correctly for it.
>
> But the controller is the same as for T1042 I presume?

No. As I know the controller on t1042 is compatible with sd host specification 3.

> The bus width is in SDHCI_HOST_CONTROL
> and the 8BIT is bit 29 in the register?

Yes, that is true.

>
> What bus width do you use and what is the failure?

4 bit sd card. I got some error like this:
mmcblk0: error -84 transferring data, sector 3911672, nr 8, cmd response 0x900, card status 0xb0

Thanks,
Kevin

>
>nk Jocke
>
>

[-- Attachment #2: Type: application/pgp-signature, Size: 473 bytes --]