Hi Arindam, Can you please check if this patch looks ok or not?
Regards, Subhash > 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 <[email protected]> > --- > drivers/mmc/core/sd.c | 81 > ++++++++++++++++++++++++++++++++----------------- > 1 files changed, 53 insertions(+), 28 deletions(-) > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c > index e2dcf23..2191dda 100644 > --- a/drivers/mmc/core/sd.c > +++ b/drivers/mmc/core/sd.c > @@ -459,56 +459,75 @@ 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 void sd_update_bus_speed_mode(struct mmc_card *card) > { > - unsigned int bus_speed = 0, timing = 0; > - int err; > - > /* > * If the host doesn't support any of the UHS-I modes, fallback on > * default speed. > */ > if (!(card->host->caps & (MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 | > - MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50))) > - return 0; > + MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50))) { > + card->sd_bus_speed = 0; > + return; > + } > > 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; > + card->sd_bus_speed = UHS_SDR104_BUS_SPEED; > } 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; > + card->sd_bus_speed = UHS_DDR50_BUS_SPEED; > } 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; > + card->sd_bus_speed = UHS_SDR50_BUS_SPEED; > } 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; > + card->sd_bus_speed = UHS_SDR25_BUS_SPEED; > } 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; > + card->sd_bus_speed = UHS_SDR12_BUS_SPEED; > + } > +} > + > +static int sd_set_bus_speed_mode(struct mmc_card *card, u8 *status) > +{ > + int err; > + unsigned int timing = 0; > + > + switch (card->sd_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; > - err = mmc_sd_switch(card, 1, 0, bus_speed, status); > + err = mmc_sd_switch(card, 1, 0, card->sd_bus_speed, status); > if (err) > return err; > > - if ((status[16] & 0xF) != bus_speed) > + if ((status[16] & 0xF) != card->sd_bus_speed) > printk(KERN_WARNING "%s: Problem setting bus speed mode!\n", > mmc_hostname(card->host)); > else { > @@ -608,18 +627,24 @@ static int mmc_sd_init_uhs_card(struct mmc_card > *card) > mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4); > } > > + /* > + * Select the bus speed mode depending on host > + * and card capability. > + */ > + sd_update_bus_speed_mode(card); > + > /* Set the driver strength for the card */ > err = sd_select_driver_type(card, status); > 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. > > -- Sent by a consultant of the Qualcomm Innovation Center, Inc. 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