diff options
Diffstat (limited to 'components')
| -rw-r--r-- | components/drivers/sdio/mmc.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/components/drivers/sdio/mmc.c b/components/drivers/sdio/mmc.c index 47c543396d..b4b6fbbad2 100644 --- a/components/drivers/sdio/mmc.c +++ b/components/drivers/sdio/mmc.c @@ -307,7 +307,7 @@ out: } /* - * Select the bus width amoung 4-bit and 8-bit(SDR). + * Select the bus width among 4-bit and 8-bit(SDR). * If the bus width is changed successfully, return the selected width value. * Zero is returned instead of error value if the wide width is not supported. */ @@ -337,22 +337,21 @@ static int mmc_select_bus_width(struct rt_mmcsd_card *card, rt_uint8_t *ext_csd) ddr = 2; } /* - * Unlike SD, MMC cards dont have a configuration register to notify + * Unlike SD, MMC cards don't have a configuration register to notify * supported bus width. So bus test command should be run to identify - * the supported bus width or compare the ext csd values of current - * bus width and ext csd values of 1 bit mode read earlier. + * the supported bus width or compare the EXT_CSD values of current + * bus width and EXT_CSD values of 1 bit mode read earlier. */ for (idx = 0; idx < sizeof(bus_widths) / sizeof(rt_uint32_t); idx++) { /* - * Host is capable of 8bit transfer, then switch - * the device to work in 8bit transfer mode. If the - * mmc switch command returns error then switch to - * 4bit transfer mode. On success set the corresponding - * bus width on the host. Meanwhile, mmc core would - * bail out early if corresponding bus capable wasn't - * set by drivers. - */ + * Determine BUS WIDTH mode according to the capability of host + */ + if (((ext_csd_bits[idx][0] == EXT_CSD_BUS_WIDTH_8) && ((host->flags & MMCSD_BUSWIDTH_8) == 0)) || + ((ext_csd_bits[idx][0] == EXT_CSD_BUS_WIDTH_4) && ((host->flags & MMCSD_BUSWIDTH_4) == 0))) + { + continue; + } bus_width = bus_widths[idx]; if (bus_width == MMCSD_BUS_WIDTH_1) { @@ -507,7 +506,7 @@ static int mmc_select_timing(struct rt_mmcsd_card *card) } else { - mmcsd_set_timing(card->host, MMCSD_TIMING_UHS_SDR50); + mmcsd_set_timing(card->host, MMCSD_TIMING_MMC_HS); mmcsd_set_clock(card->host, card->hs_max_data_rate); } |