Re: [PATCH] libertas/sdio: 8686: set ECSI bit for 1-bit transfers

From: Dan Williams
Date: Tue Apr 06 2010 - 12:08:21 EST


On Tue, 2010-04-06 at 10:52 +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.
>
> Signed-off-by: Daniel Mack <daniel@xxxxxxxx>
> Cc: Alagu Sankar <alagusankar@xxxxxxxxxxx>
> Cc: Volker Ernst <volker.ernst@xxxxxxxx>
> Cc: Dan Williams <dcbw@xxxxxxxxxx>
> Cc: John W. Linville <linville@xxxxxxxxxxxxx>
> Cc: Holger Schurig <hs4233@xxxxxxxxxxxxxxxxxxxx>
> Cc: Bing Zhao <bzhao@xxxxxxxxxxx>
> Cc: libertas-dev@xxxxxxxxxxxxxxxxxxx
> Cc: linux-wireless@xxxxxxxxxxxxxxx
> Cc: linux-mmc@xxxxxxxxxxxxxxx

Acked-by: Dan Williams <dcbw@xxxxxxxxxx>

> ---
> drivers/net/wireless/libertas/if_sdio.c | 22 ++++++++++++++++++++++
> include/linux/mmc/sdio.h | 2 ++
> 2 files changed, 24 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c
> index 7a73f62..33206a9 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 +1025,25 @@ static int if_sdio_probe(struct sdio_func *func,
> if (ret)
> goto disable;
>
> + /* For 1-bit transfers to the 8686 model, 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 ((card->model == IF_SDIO_MODEL_8686) &&
> + (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
>


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