Can you please try this diff and see if it works for you. Will do formal patch after your testing. What card is failing ? Please let me know the manufacturing information so can add card to my test suite. Philip diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 1d8409f..77072c8 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -558,6 +558,8 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, EXT_CSD_BUS_WIDTH, ext_csd_bits[idx][0]); if (!err) { + mmc_set_bus_width_ddr(card->host, + bus_width, MMC_SDR_MODE); /* * If controller can't handle bus width test, * use the highest bus width to maintain @@ -565,8 +567,6 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, */ if (!(host->caps & MMC_CAP_BUS_WIDTH_TEST)) break; - mmc_set_bus_width_ddr(card->host, - bus_width, MMC_SDR_MODE); err = mmc_bus_test(card, bus_width); if (!err) break; @@ -586,7 +586,8 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, } else if (ddr) { mmc_card_set_ddr_mode(card); mmc_set_bus_width_ddr(card->host, bus_width, ddr); - } + } else + mmc_set_bus_width (card->host, bus_width); } if (!oldcard) Philip On Dec 21, 2010, at 2:59 AM, zhangfei gao wrote: > On Fri, Dec 17, 2010 at 3:11 AM, Takashi Iwai <tiwai@xxxxxxx> wrote: >> At Fri, 17 Dec 2010 03:43:42 +0000, >> Chris Ball wrote: >>> >>> Hi Philip, >>> >>> On Thu, Dec 16, 2010 at 06:33:49PM -0800, Philip Rakity wrote: >>>> It is not possible for bus_width to be not initialized. This would imply ARRAY_SIZE(bus_widths) is 1. Certainly not true. >>> >>> Right, I agree. We should fix the warning anyway. >> >> Well, this is always a gray-zone question. One prefers fixing it >> either via uninitialized_var() or by setting a bogus value. But, this >> would cover any possible real bug in future. Thus another prefers >> ignoring it, because it's just a compiler bug (mostly of old gcc). >> >> After all, it's up to maintainer, so take as you like :) >> >> >> thanks, >> >> Takashi >> >> >>>> We could just initialize by changing >>>> + unsigned idx, bus_width; >>>> to >>>> + unsigned idx, bus_width = 0; >>> >>> Okay, I've pushed to mmc-next with that change. >>> >>>> I wonder what compiler are you using so we can avoid this issue in future. >>> >>> Ah, good point -- I was building with a gcc 4.1.2 ARM cross-compiler, >>> and using a gcc 4.5.1 cross-build instead avoids the warning. >>> >>> Thanks, >>> >>> -- >>> Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/> >>> One Laptop Per Child >>> >> > > Could you help adding this modification? > We found error happen since bus_width is not set at these condition: > 1. ddr=0 > 2. not set MMC_CAP_BUS_WIDTH_TEST > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index 1d8409f..86cac0d 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -586,7 +586,11 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, > } else if (ddr) { > mmc_card_set_ddr_mode(card); > mmc_set_bus_width_ddr(card->host, bus_width, ddr); > - } > + > + } else > + mmc_set_bus_width(card->host, > + bus_widths[idx]); > + > } > > if (!oldcard) -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html