mmc: core: Fixup suspend/resume issues for UHS-I cards

Even if cards supports 1.8V I/O voltage those should anyway be
initialized at 3.3V I/O according to (e)MMC, SD and SDIO specs.
Some eMMC and embedded SDIO devices are able to be initialized
at 1.8V as well, but it is better to be safe.

Do note that initialization in this context means that the card
has been completely powered off, otherwise the card will remain
at the last I/O voltage level that were negotitiated.

Due to the above being taken care of the suspend/resume issues
for UHS-I SD-cards has been fixed.

Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Acked-by: Philip Rakity <prakity@marvell.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 690255c7d4dcc8c407e7b0852216edab75f4ef31..132378b89d76a0072fe31b7f436975525d04e353 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2068,6 +2068,9 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
         */
        mmc_hw_reset_for_init(host);
 
+       /* Initialization should be done at 3.3 V I/O voltage. */
+       mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
+
        /*
         * sdio_reset sends CMD52 to reset card.  Since we do not know
         * if the card is being re-initialized, just send it.  CMD52

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index a48066344fa87316997b0bcca501d0842ea7e8a1..2b9ed1401dc439bf1dd29e4aa751f74e0175bc93 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -816,6 +816,9 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
        if (!mmc_host_is_spi(host))
                mmc_set_bus_mode(host, MMC_BUSMODE_OPENDRAIN);
 
+       /* Initialization should be done at 3.3 V I/O voltage. */
+       mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
+
        /*
         * Since we're changing the OCR value, we seem to
         * need to tell some cards to go back to the idle

diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 5017f9354ce28af6a67418d1ce0a2c438ed07edd..c272c6868ecf6d11a39c3cf2be99f1257fccd026 100644 (file)
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -911,6 +911,9 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
        BUG_ON(!host);
        WARN_ON(!host->claimed);
 
+       /* The initialization should be done at 3.3 V I/O voltage. */
+       mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
+
        err = mmc_sd_get_cid(host, ocr, cid, &rocr);
        if (err)
                return err;
@@ -1156,11 +1159,6 @@ int mmc_attach_sd(struct mmc_host *host)
        BUG_ON(!host);
        WARN_ON(!host->claimed);
 
-       /* Make sure we are at 3.3V signalling voltage */
-       err = mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, false);
-       if (err)
-               return err;
-
        /* Disable preset value enable if already set since last time */
        if (host->ops->enable_preset_value) {
                mmc_host_clk_hold(host);

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 12cde6ee17f50732ac5cd05f6843928abf87d0c9..2c7c83f832d289c25eaf83cf4d7ef32d420fb002 100644 (file)
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -585,6 +585,9 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
         * Inform the card of the voltage
         */
        if (!powered_resume) {
+               /* The initialization should be done at 3.3 V I/O voltage. */
+               mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
+
                err = mmc_send_io_op_cond(host, host->ocr, &ocr);
                if (err)
                        goto err;
@@ -996,6 +999,11 @@ static int mmc_sdio_power_restore(struct mmc_host *host)
         * With these steps taken, mmc_select_voltage() is also required to
         * restore the correct voltage setting of the card.
         */
+
+       /* The initialization should be done at 3.3 V I/O voltage. */
+       if (!mmc_card_keep_power(host))
+               mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_330, 0);
+
        sdio_reset(host);
        mmc_go_idle(host);
        mmc_send_if_cond(host, host->ocr_avail);