From 1dc5a61559e73472cd84bc8aa5b297ec0deba4de Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Thu, 30 Apr 2020 11:16:40 +0200 Subject: [PATCH] mmc: sdio: Align the initialization commands in retry path for UHS-I According to the comment in mmc_sdio_reinit_card(), some SDIO cards may require a "[CMD5,5,3,7] init sequence", which isn't always obeyed in mmc_sdio_init_card(). Especially, when we end up retrying the UHS-I specific initialization, there is a missing CMD5. Let's update the code to make the behaviour consistent and let's also take the opportunity to clean up the code a bit, to avoid open coding. Signed-off-by: Ulf Hansson Link: https://lore.kernel.org/r/20200430091640.455-5-ulf.hansson@linaro.org --- drivers/mmc/core/sdio.c | 53 ++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 27 deletions(-) diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c index 853ac65f0485..435de47a6ee0 100644 --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -543,13 +543,33 @@ out: return err; } -static void mmc_sdio_resend_if_cond(struct mmc_host *host, u32 ocr, - struct mmc_card *card) +static int mmc_sdio_pre_init(struct mmc_host *host, u32 ocr, + struct mmc_card *card) { + if (card) + mmc_remove_card(card); + + /* + * Reset the card by performing the same steps that are taken by + * mmc_rescan_try_freq() and mmc_attach_sdio() during a "normal" probe. + * + * sdio_reset() is technically not needed. Having just powered up the + * hardware, it should already be in reset state. However, some + * platforms (such as SD8686 on OLPC) do not instantly cut power, + * meaning that a reset is required when restoring power soon after + * powering off. It is harmless in other cases. + * + * The CMD5 reset (mmc_send_io_op_cond()), according to the SDIO spec, + * is not necessary for non-removable cards. However, it is required + * for OLPC SD8686 (which expects a [CMD5,5,3,7] init sequence), and + * harmless in other situations. + * + */ + sdio_reset(host); mmc_go_idle(host); mmc_send_if_cond(host, ocr); - mmc_remove_card(card); + return mmc_send_io_op_cond(host, 0, NULL); } /* @@ -640,7 +660,7 @@ try_again: if (rocr & ocr & R4_18V_PRESENT) { err = mmc_set_uhs_voltage(host, ocr_card); if (err == -EAGAIN) { - mmc_sdio_resend_if_cond(host, ocr_card, card); + mmc_sdio_pre_init(host, ocr_card, card); retries--; goto try_again; } else if (err) { @@ -712,7 +732,7 @@ try_again: */ err = sdio_read_cccr(card, ocr); if (err) { - mmc_sdio_resend_if_cond(host, ocr_card, card); + mmc_sdio_pre_init(host, ocr_card, card); if (ocr & R4_18V_PRESENT) { /* Retry init sequence, but without R4_18V_PRESENT. */ retries = 0; @@ -813,28 +833,7 @@ static int mmc_sdio_reinit_card(struct mmc_host *host) { int ret; - /* - * Reset the card by performing the same steps that are taken by - * mmc_rescan_try_freq() and mmc_attach_sdio() during a "normal" probe. - * - * sdio_reset() is technically not needed. Having just powered up the - * hardware, it should already be in reset state. However, some - * platforms (such as SD8686 on OLPC) do not instantly cut power, - * meaning that a reset is required when restoring power soon after - * powering off. It is harmless in other cases. - * - * The CMD5 reset (mmc_send_io_op_cond()), according to the SDIO spec, - * is not necessary for non-removable cards. However, it is required - * for OLPC SD8686 (which expects a [CMD5,5,3,7] init sequence), and - * harmless in other situations. - * - */ - - sdio_reset(host); - mmc_go_idle(host); - mmc_send_if_cond(host, host->card->ocr); - - ret = mmc_send_io_op_cond(host, 0, NULL); + ret = mmc_sdio_pre_init(host, host->card->ocr, NULL); if (ret) return ret;