Hi Martin, On Mon, Apr 15 2013, Martin Fuzzey wrote: > Currently SDIO interrupts do not work on i.MX53 and maybe others. > > This was observed with a Marvell 8787 based SDIO wifi adapter > using the mwifiex driver and firmware from the Marvell git > repository. > The symptom was a timeout after firmware download. > > Observing the SDIO_DAT1 line showed that an interrupt was requested > (level 0) but no interrupt was generated in software, the line > stayed low until a timeout ocurred and the card was reset. > > There is a Freescale errata > ENGcm11186 "eSDHC misses SDIO interrupt when CINT is disabled" > > The workaround suggested by this errata is already implemented and > involves clearing and then setting the D3CD bit in the host control > register [see esdhc_writel_le()] > > However, when esdhc_writeb_le() is later used to write to > SDHCI_HOST_CONTROL it always resets the D3CD bit. > > To fix this simply add the D3CD bit to the set of bits > not modified by esdhc_writeb_le(). > > Signed-off-by: Martin Fuzzey <[email protected]> > --- > drivers/mmc/host/sdhci-esdhc-imx.c | 4 +++- > 1 files changed, 3 insertions(+), 1 deletions(-) > > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c > b/drivers/mmc/host/sdhci-esdhc-imx.c > index 78ac002..3c4c63d 100644 > --- a/drivers/mmc/host/sdhci-esdhc-imx.c > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c > @@ -324,8 +324,10 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 > val, int reg) > /* > * Do not touch buswidth bits here. This is done in > * esdhc_pltfm_bus_width. > + * Do not touch the D3CD bit either which is used for the > + * SDIO interrupt errata workaround. > */ > - mask = 0xffff & ~ESDHC_CTRL_BUSWIDTH_MASK; > + mask = 0xffff & ~(ESDHC_CTRL_BUSWIDTH_MASK | ESDHC_CTRL_D3CD); > > esdhc_clrset_le(host, mask, new_val, reg); > return;
I didn't see any review comments from other -imx developers -- I've applied this to mmc-next now, hopefully someone will yell if there's any reason not to. Thanks, - Chris. -- Chris Ball <[email protected]> <http://printf.net/> One Laptop Per Child -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
