Chris, Arindam, Philip, Please let me know you comments on this reworked patch.
Regards, Subhash > -----Original Message----- > From: linux-arm-msm-ow...@vger.kernel.org [mailto:linux-arm-msm- > ow...@vger.kernel.org] On Behalf Of Subhash Jadavani > Sent: Thursday, August 04, 2011 4:08 PM > To: linux-mmc@vger.kernel.org > Cc: linux-arm-...@vger.kernel.org; Subhash Jadavani > Subject: [PATCH v1 1/1] mmc: sd: UHS-I bus speed should be set last in > UHS initialization > > mmc_sd_init_uhs_card function sets the driver type, current limit > and bus speed mode on card as well as on host controller side. > > Currently bus speed mode is set by sending CMD6 to card and > immediately setting the timing mode in host controller. But > then before initiating tuning sequence, it also tries to set > current limit by sending CMD6 to card which results in data > timeout errors in controller if bus speed mode is SDR50/SDR104 mode. > > So basically bus speed mode should be set only after current limit > is set in the card and immediately after setting the bus speed mode, > tuning sequence should be initiated. > > Signed-off-by: Subhash Jadavani <subha...@codeaurora.org> > --- > drivers/mmc/core/sd.c | 65 ++++++++++++++++++++++++++++++++++------- > -------- > 1 files changed, 45 insertions(+), 20 deletions(-) > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c > index ff27741..769e587 100644 > --- a/drivers/mmc/core/sd.c > +++ b/drivers/mmc/core/sd.c > @@ -459,10 +459,9 @@ static int sd_select_driver_type(struct mmc_card > *card, u8 *status) > return 0; > } > > -static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status) > +static int sd_get_bus_speed_mode(struct mmc_card *card) > { > - unsigned int bus_speed = 0, timing = 0; > - int err; > + int bus_speed = 0; > > /* > * If the host doesn't support any of the UHS-I modes, fallback > on > @@ -475,32 +474,57 @@ static int sd_set_bus_speed_mode(struct mmc_card > *card, u8 *status) > if ((card->host->caps & MMC_CAP_UHS_SDR104) && > (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR104)) { > bus_speed = UHS_SDR104_BUS_SPEED; > - timing = MMC_TIMING_UHS_SDR104; > - card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR; > } else if ((card->host->caps & MMC_CAP_UHS_DDR50) && > (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_DDR50)) { > bus_speed = UHS_DDR50_BUS_SPEED; > - timing = MMC_TIMING_UHS_DDR50; > - card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR; > } else if ((card->host->caps & (MMC_CAP_UHS_SDR104 | > MMC_CAP_UHS_SDR50)) && (card->sw_caps.sd3_bus_mode & > SD_MODE_UHS_SDR50)) { > bus_speed = UHS_SDR50_BUS_SPEED; > - timing = MMC_TIMING_UHS_SDR50; > - card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR; > } else if ((card->host->caps & (MMC_CAP_UHS_SDR104 | > MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25)) && > (card->sw_caps.sd3_bus_mode & SD_MODE_UHS_SDR25)) { > bus_speed = UHS_SDR25_BUS_SPEED; > - timing = MMC_TIMING_UHS_SDR25; > - card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR; > } else if ((card->host->caps & (MMC_CAP_UHS_SDR104 | > MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR25 | > MMC_CAP_UHS_SDR12)) && (card->sw_caps.sd3_bus_mode & > SD_MODE_UHS_SDR12)) { > bus_speed = UHS_SDR12_BUS_SPEED; > - timing = MMC_TIMING_UHS_SDR12; > - card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR; > + } > + > + return bus_speed; > +} > + > +static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status) > +{ > + int err, bus_speed; > + unsigned int timing = 0; > + > + bus_speed = sd_get_bus_speed_mode(card); > + > + switch (bus_speed) { > + case UHS_SDR104_BUS_SPEED: > + timing = MMC_TIMING_UHS_SDR104; > + card->sw_caps.uhs_max_dtr = UHS_SDR104_MAX_DTR; > + break; > + case UHS_DDR50_BUS_SPEED: > + timing = MMC_TIMING_UHS_DDR50; > + card->sw_caps.uhs_max_dtr = UHS_DDR50_MAX_DTR; > + break; > + case UHS_SDR50_BUS_SPEED: > + timing = MMC_TIMING_UHS_SDR50; > + card->sw_caps.uhs_max_dtr = UHS_SDR50_MAX_DTR; > + break; > + case UHS_SDR25_BUS_SPEED: > + timing = MMC_TIMING_UHS_SDR25; > + card->sw_caps.uhs_max_dtr = UHS_SDR25_MAX_DTR; > + break; > + case UHS_SDR12_BUS_SPEED: > + timing = MMC_TIMING_UHS_SDR12; > + card->sw_caps.uhs_max_dtr = UHS_SDR12_MAX_DTR; > + break; > + default: > + return 0; > } > > card->sd_bus_speed = bus_speed; > @@ -522,6 +546,7 @@ static int sd_set_bus_speed_mode(struct mmc_card > *card, u8 *status) > static int sd_set_current_limit(struct mmc_card *card, u8 *status) > { > int current_limit = 0; > + unsigned int bus_speed = sd_get_bus_speed_mode(card); > int err; > > /* > @@ -529,9 +554,9 @@ static int sd_set_current_limit(struct mmc_card > *card, u8 *status) > * bus speed modes. For other bus speed modes, we set the default > * current limit of 200mA. > */ > - if ((card->sd_bus_speed == UHS_SDR50_BUS_SPEED) || > - (card->sd_bus_speed == UHS_SDR104_BUS_SPEED) || > - (card->sd_bus_speed == UHS_DDR50_BUS_SPEED)) { > + if ((bus_speed == UHS_SDR50_BUS_SPEED) || > + (bus_speed == UHS_SDR104_BUS_SPEED) || > + (bus_speed == UHS_DDR50_BUS_SPEED)) { > if (card->host->caps & MMC_CAP_MAX_CURRENT_800) { > if (card->sw_caps.sd3_curr_limit & > SD_MAX_CURRENT_800) > current_limit = SD_SET_CURRENT_LIMIT_800; > @@ -613,13 +638,13 @@ static int mmc_sd_init_uhs_card(struct mmc_card > *card) > if (err) > goto out; > > - /* Set bus speed mode of the card */ > - err = sd_set_bus_speed_mode(card, status); > + /* Set current limit for the card */ > + err = sd_set_current_limit(card, status); > if (err) > goto out; > > - /* Set current limit for the card */ > - err = sd_set_current_limit(card, status); > + /* Set bus speed mode of the card */ > + err = sd_set_bus_speed_mode(card, status); > if (err) > goto out; > > -- > 1.7.1.1 > > -- > Sent by a consultant of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora > Forum. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm- > msm" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
