Re: [PATCH] libertas/sdio: set ECSI bit for 1-bit transfers

[Dan Williams <dcbw@redhat.com>]

On Wed, 2010-03-31 at 15:31 +0200, Daniel Mack wrote:
> When operating in 1-bit mode, SDAT1 is used as dedicated interrupt line.
> However, the 8686 will only drive this line when the ECSI bit is set in
> the CCCR_IF register.
> 
> Thanks to Alagu Sankar for pointing me in the right direction.

Could you modify the patch to do this *only* for the 8686?  Apparently
only the 8686 this hardware "quirk" and thus this might have odd
side-effects on the 8688 or the 8385.

Check the 'struct if_sdio_card' model member and compare it to
IF_SDIO_MODEL_8686 like if_sdio_probe() does.

Thanks!
Dan

> Signed-off-by: Daniel Mack <daniel@caiaq.de>
> Cc: Alagu Sankar <alagusankar@embwise.com>
> Cc: Volker Ernst <volker.ernst@txtr.com>
> Cc: Dan Williams <dcbw@redhat.com>
> Cc: John W. Linville <linville@tuxdriver.com>
> Cc: Holger Schurig <hs4233@mail.mn-solutions.de>
> Cc: Bing Zhao <bzhao@marvell.com>
> Cc: libertas-dev@lists.infradead.org
> Cc: linux-wireless@vger.kernel.org
> Cc: linux-mmc@vger.kernel.org
> ---
>  drivers/net/wireless/libertas/if_sdio.c |   21 +++++++++++++++++++++
>  include/linux/mmc/sdio.h                |    2 ++
>  2 files changed, 23 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c
> index 7a73f62..f89bb8b 100644
> --- a/drivers/net/wireless/libertas/if_sdio.c
> +++ b/drivers/net/wireless/libertas/if_sdio.c
> @@ -34,6 +34,8 @@
>  #include <linux/mmc/card.h>
>  #include <linux/mmc/sdio_func.h>
>  #include <linux/mmc/sdio_ids.h>
> +#include <linux/mmc/sdio.h>
> +#include <linux/mmc/host.h>
>  
>  #include "host.h"
>  #include "decl.h"
> @@ -942,6 +944,7 @@ static int if_sdio_probe(struct sdio_func *func,
>  	int ret, i;
>  	unsigned int model;
>  	struct if_sdio_packet *packet;
> +	struct mmc_host *host = func->card->host;
>  
>  	lbs_deb_enter(LBS_DEB_SDIO);
>  
> @@ -1022,6 +1025,24 @@ static int if_sdio_probe(struct sdio_func *func,
>  	if (ret)
>  		goto disable;
>  
> +	/* For 1-bit transfers, we need to enable the interrupt flag in
> +	 * the CCCR register. Set the MMC_QUIRK_LENIENT_FN0 bit to allow
> +	 * access to non-vendor registers. */
> +	if ((host->caps & MMC_CAP_SDIO_IRQ) &&
> +	    (host->ios.bus_width == MMC_BUS_WIDTH_1)) {
> +		u8 reg;
> +
> +		func->card->quirks |= MMC_QUIRK_LENIENT_FN0;
> +		reg = sdio_f0_readb(func, SDIO_CCCR_IF, &ret);
> +		if (ret)
> +			goto release_int;
> +
> +		reg |= SDIO_BUS_ECSI;
> +		sdio_f0_writeb(func, reg, SDIO_CCCR_IF, &ret);
> +		if (ret)
> +			goto release_int;
> +	}
> +
>  	card->ioport = sdio_readb(func, IF_SDIO_IOPORT, &ret);
>  	if (ret)
>  		goto release_int;
> diff --git a/include/linux/mmc/sdio.h b/include/linux/mmc/sdio.h
> index 0ebaef5..329a8fa 100644
> --- a/include/linux/mmc/sdio.h
> +++ b/include/linux/mmc/sdio.h
> @@ -94,6 +94,8 @@
>  
>  #define  SDIO_BUS_WIDTH_1BIT	0x00
>  #define  SDIO_BUS_WIDTH_4BIT	0x02
> +#define  SDIO_BUS_ECSI		0x20	/* Enable continuous SPI interrupt */
> +#define  SDIO_BUS_SCSI		0x40	/* Support continuous SPI interrupt */
>  
>  #define  SDIO_BUS_ASYNC_INT	0x20
>