The JEDEC specification indicates CMD13 can be used after a HS200 switch to check for errors. However in practice some boards experience CRC errors in the CMD13 response. Consequently, for HS200, CRC errors are not a reliable way to know the switch failed. If there really is a problem, we would expect tuning will fail and the result ends up the same. So change the error condition to ignore CRC errors in that case. Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> --- drivers/mmc/core/mmc.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 3268fcd3378d..34d30e2a09ff 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1223,7 +1223,12 @@ int mmc_hs400_to_hs200(struct mmc_card *card) mmc_set_timing(host, MMC_TIMING_MMC_HS200); err = mmc_switch_status(card); - if (err) + /* + * For HS200, CRC errors are not a reliable way to know the switch + * failed. If there really is a problem, we would expect tuning will + * fail and the result ends up the same. + */ + if (err && err != -EILSEQ) goto out_err; mmc_set_bus_speed(card); @@ -1387,6 +1392,14 @@ static int mmc_select_hs200(struct mmc_card *card) err = mmc_switch_status(card); /* + * For HS200, CRC errors are not a reliable way to know the + * switch failed. If there really is a problem, we would expect + * tuning will fail and the result ends up the same. + */ + if (err == -EILSEQ) + err = 0; + + /* * mmc_select_timing() assumes timing has not changed if * it is a switch error. */ -- 1.9.1 -- 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
