2 files changed, 233 insertions, 200 deletions

diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c
index 509229b48b55..1f730dbfaeea 100644
--- a/drivers/mmc/core/debugfs.c
+++ b/drivers/mmc/core/debugfs.c
@@ -139,7 +139,7 @@ static int mmc_ios_show(struct seq_file *s, void *data)
                 str = "mmc DDR52";
                 break;
         case MMC_TIMING_MMC_HS200:
-                str = "mmc high-speed SDR200";
+                str = "mmc HS200";
                 break;
         default:
                 str = "invalid";
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 4538541ac5ab..bec6786efd19 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -242,7 +242,7 @@ static void mmc_select_card_type(struct mmc_card *card)
         struct mmc_host *host = card->host;
         u8 card_type = card->ext_csd.raw_card_type & EXT_CSD_CARD_TYPE_MASK;
         u32 caps = host->caps, caps2 = host->caps2;
-        unsigned int hs_max_dtr = 0;
+        unsigned int hs_max_dtr = 0, hs200_max_dtr = 0;
         unsigned int avail_type = 0;
 
         if (caps & MMC_CAP_MMC_HIGHSPEED &&
@@ -271,17 +271,18 @@ static void mmc_select_card_type(struct mmc_card *card)
 
         if (caps2 & MMC_CAP2_HS200_1_8V_SDR &&
             card_type & EXT_CSD_CARD_TYPE_HS200_1_8V) {
-                hs_max_dtr = MMC_HS200_MAX_DTR;
+                hs200_max_dtr = MMC_HS200_MAX_DTR;
                 avail_type |= EXT_CSD_CARD_TYPE_HS200_1_8V;
         }
 
         if (caps2 & MMC_CAP2_HS200_1_2V_SDR &&
             card_type & EXT_CSD_CARD_TYPE_HS200_1_2V) {
-                hs_max_dtr = MMC_HS200_MAX_DTR;
+                hs200_max_dtr = MMC_HS200_MAX_DTR;
                 avail_type |= EXT_CSD_CARD_TYPE_HS200_1_2V;
         }
 
         card->ext_csd.hs_max_dtr = hs_max_dtr;
+        card->ext_csd.hs200_max_dtr = hs200_max_dtr;
         card->mmc_avail_type = avail_type;
 }
 
@@ -825,37 +826,46 @@ static int mmc_select_powerclass(struct mmc_card *card)
 }
 
 /*
- * Selects the desired buswidth and switch to the HS200 mode
- * if bus width set without error
+ * Set the bus speed for the selected speed mode.
  */
-static int mmc_select_hs200(struct mmc_card *card)
+static void mmc_set_bus_speed(struct mmc_card *card)
+{
+        unsigned int max_dtr = (unsigned int)-1;
+
+        if (mmc_card_hs200(card) && max_dtr > card->ext_csd.hs200_max_dtr)
+                max_dtr = card->ext_csd.hs200_max_dtr;
+        else if (mmc_card_hs(card) && max_dtr > card->ext_csd.hs_max_dtr)
+                max_dtr = card->ext_csd.hs_max_dtr;
+        else if (max_dtr > card->csd.max_dtr)
+                max_dtr = card->csd.max_dtr;
+
+        mmc_set_clock(card->host, max_dtr);
+}
+
+/*
+ * Select the bus width amoung 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.
+ */
+static int mmc_select_bus_width(struct mmc_card *card)
 {
-        int idx, err = -EINVAL;
-        struct mmc_host *host;
         static unsigned ext_csd_bits[] = {
-                EXT_CSD_BUS_WIDTH_4,
                 EXT_CSD_BUS_WIDTH_8,
+                EXT_CSD_BUS_WIDTH_4,
         };
         static unsigned bus_widths[] = {
-                MMC_BUS_WIDTH_4,
                 MMC_BUS_WIDTH_8,
+                MMC_BUS_WIDTH_4,
         };
+        struct mmc_host *host = card->host;
+        unsigned idx, bus_width = 0;
+        int err = 0;
 
-        BUG_ON(!card);
-
-        host = card->host;
-
-        if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V)
-                err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);
-
-        if (err && card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_8V)
-                err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180);
-
-        /* If fails try again during next card power cycle */
-        if (err)
-                goto err;
+        if ((card->csd.mmca_vsn < CSD_SPEC_VER_4) &&
+            !(host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA)))
+                return 0;
 
-        idx = (host->caps & MMC_CAP_8_BIT_DATA) ? 1 : 0;
+        idx = (host->caps & MMC_CAP_8_BIT_DATA) ? 0 : 1;
 
         /*
          * Unlike SD, MMC cards dont have a configuration register to notify
@@ -863,8 +873,7 @@ static int mmc_select_hs200(struct mmc_card *card)
          * 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--) {
-
+        for (; idx < ARRAY_SIZE(bus_widths); idx++) {
                 /*
                  * Host is capable of 8bit transfer, then switch
                  * the device to work in 8bit transfer mode. If the
@@ -879,27 +888,202 @@ static int mmc_select_hs200(struct mmc_card *card)
                 if (err)
                         continue;
 
-                mmc_set_bus_width(card->host, bus_widths[idx]);
+                bus_width = bus_widths[idx];
+                mmc_set_bus_width(host, bus_width);
 
+                /*
+                 * If controller can't handle bus width test,
+                 * compare ext_csd previously read in 1 bit mode
+                 * against ext_csd at new bus width
+                 */
                 if (!(host->caps & MMC_CAP_BUS_WIDTH_TEST))
-                        err = mmc_compare_ext_csds(card, bus_widths[idx]);
+                        err = mmc_compare_ext_csds(card, bus_width);
                 else
-                        err = mmc_bus_test(card, bus_widths[idx]);
-                if (!err)
+                        err = mmc_bus_test(card, bus_width);
+
+                if (!err) {
+                        err = bus_width;
                         break;
+                } else {
+                        pr_warn("%s: switch to bus width %d failed\n",
+                                mmc_hostname(host), ext_csd_bits[idx]);
+                }
         }
 
-        /* switch to HS200 mode if bus width set successfully */
+        return err;
+}
+
+/*
+ * Switch to the high-speed mode
+ */
+static int mmc_select_hs(struct mmc_card *card)
+{
+        int err;
+
+        err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                           EXT_CSD_HS_TIMING, EXT_CSD_TIMING_HS,
+                           card->ext_csd.generic_cmd6_time,
+                           true, true, true);
         if (!err)
+                mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
+
+        return err;
+}
+
+/*
+ * Activate wide bus and DDR if supported.
+ */
+static int mmc_select_hs_ddr(struct mmc_card *card)
+{
+        struct mmc_host *host = card->host;
+        u32 bus_width, ext_csd_bits;
+        int err = 0;
+
+        if (!(card->mmc_avail_type & EXT_CSD_CARD_TYPE_DDR_52))
+                return 0;
+
+        bus_width = host->ios.bus_width;
+        if (bus_width == MMC_BUS_WIDTH_1)
+                return 0;
+
+        ext_csd_bits = (bus_width == MMC_BUS_WIDTH_8) ?
+                EXT_CSD_DDR_BUS_WIDTH_8 : EXT_CSD_DDR_BUS_WIDTH_4;
+
+        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                        EXT_CSD_BUS_WIDTH,
+                        ext_csd_bits,
+                        card->ext_csd.generic_cmd6_time);
+        if (err) {
+                pr_warn("%s: switch to bus width %d ddr failed\n",
+                        mmc_hostname(host), 1 << bus_width);
+                return err;
+        }
+
+        /*
+         * eMMC cards can support 3.3V to 1.2V i/o (vccq)
+         * signaling.
+         *
+         * EXT_CSD_CARD_TYPE_DDR_1_8V means 3.3V or 1.8V vccq.
+         *
+         * 1.8V vccq at 3.3V core voltage (vcc) is not required
+         * in the JEDEC spec for DDR.
+         *
+         * Do not force change in vccq since we are obviously
+         * working and no change to vccq is needed.
+         *
+         * WARNING: eMMC rules are NOT the same as SD DDR
+         */
+        if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_DDR_1_2V) {
+                err = __mmc_set_signal_voltage(host,
+                                MMC_SIGNAL_VOLTAGE_120);
+                if (err)
+                        return err;
+        }
+
+        mmc_set_timing(host, MMC_TIMING_MMC_DDR52);
+
+        return err;
+}
+
+/*
+ * For device supporting HS200 mode, the following sequence
+ * should be done before executing the tuning process.
+ * 1. set the desired bus width(4-bit or 8-bit, 1-bit is not supported)
+ * 2. switch to HS200 mode
+ * 3. set the clock to > 52Mhz and <=200MHz
+ */
+static int mmc_select_hs200(struct mmc_card *card)
+{
+        struct mmc_host *host = card->host;
+        int err = -EINVAL;
+
+        if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V)
+                err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);
+
+        if (err && card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_8V)
+                err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180);
+
+        /* If fails try again during next card power cycle */
+        if (err)
+                goto err;
+
+        /*
+         * Set the bus width(4 or 8) with host's support and
+         * switch to HS200 mode if bus width is set successfully.
+         */
+        err = mmc_select_bus_width(card);
+        if (!IS_ERR_VALUE(err)) {
                 err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
-                                EXT_CSD_HS_TIMING, 2,
-                                card->ext_csd.generic_cmd6_time,
-                                true, true, true);
+                                   EXT_CSD_HS_TIMING, EXT_CSD_TIMING_HS200,
+                                   card->ext_csd.generic_cmd6_time,
+                                   true, true, true);
+                if (!err)
+                        mmc_set_timing(host, MMC_TIMING_MMC_HS200);
+        }
 err:
         return err;
 }
 
 /*
+ * Activate High Speed or HS200 mode if supported.
+ */
+static int mmc_select_timing(struct mmc_card *card)
+{
+        int err = 0;
+
+        if ((card->csd.mmca_vsn < CSD_SPEC_VER_4 &&
+             card->ext_csd.hs_max_dtr == 0))
+                goto bus_speed;
+
+        if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200)
+                err = mmc_select_hs200(card);
+        else if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS)
+                err = mmc_select_hs(card);
+
+        if (err && err != -EBADMSG)
+                return err;
+
+        if (err) {
+                pr_warn("%s: switch to %s failed\n",
+                        mmc_card_hs(card) ? "high-speed" :
+                        (mmc_card_hs200(card) ? "hs200" : ""),
+                        mmc_hostname(card->host));
+                err = 0;
+        }
+
+bus_speed:
+        /*
+         * Set the bus speed to the selected bus timing.
+         * If timing is not selected, backward compatible is the default.
+         */
+        mmc_set_bus_speed(card);
+        return err;
+}
+
+/*
+ * Execute tuning sequence to seek the proper bus operating
+ * conditions for HS200, which sends CMD21 to the device.
+ */
+static int mmc_hs200_tuning(struct mmc_card *card)
+{
+        struct mmc_host *host = card->host;
+        int err = 0;
+
+        if (host->ops->execute_tuning) {
+                mmc_host_clk_hold(host);
+                err = host->ops->execute_tuning(host,
+                                MMC_SEND_TUNING_BLOCK_HS200);
+                mmc_host_clk_release(host);
+
+                if (err)
+                        pr_warn("%s: tuning execution failed\n",
+                                mmc_hostname(host));
+        }
+
+        return err;
+}
+
+/*
  * Handle the detection and initialisation of a card.
  *
  * In the case of a resume, "oldcard" will contain the card
@@ -909,9 +1093,8 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
         struct mmc_card *oldcard)
 {
         struct mmc_card *card;
-        int err, ddr = 0;
+        int err;
         u32 cid[4];
-        unsigned int max_dtr;
         u32 rocr;
         u8 *ext_csd = NULL;
 
@@ -1103,173 +1286,23 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
         }
 
         /*
-         * Activate high speed (if supported)
-         */
-        if (card->ext_csd.hs_max_dtr != 0) {
-                err = 0;
-                if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200)
-                        err = mmc_select_hs200(card);
-                else if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS)
-                        err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
-                                        EXT_CSD_HS_TIMING, 1,
-                                        card->ext_csd.generic_cmd6_time,
-                                        true, true, true);
-
-                if (err && err != -EBADMSG)
-                        goto free_card;
-
-                if (err) {
-                        pr_warning("%s: switch to highspeed failed\n",
-                               mmc_hostname(card->host));
-                        err = 0;
-                } else {
-                        if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200)
-                                mmc_set_timing(card->host,
-                                               MMC_TIMING_MMC_HS200);
-                        else
-                                mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
-                }
-        }
-
-        /*
-         * Compute bus speed.
-         */
-        max_dtr = (unsigned int)-1;
-
-        if (mmc_card_hs(card) || mmc_card_hs200(card)) {
-                if (max_dtr > card->ext_csd.hs_max_dtr)
-                        max_dtr = card->ext_csd.hs_max_dtr;
-                if (mmc_card_hs(card) && (max_dtr > 52000000))
-                        max_dtr = 52000000;
-        } else if (max_dtr > card->csd.max_dtr) {
-                max_dtr = card->csd.max_dtr;
-        }
-
-        mmc_set_clock(host, max_dtr);
-
-        /*
-         * Indicate DDR mode (if supported).
+         * Select timing interface
          */
-        if (mmc_card_hs(card))
-                ddr = card->mmc_avail_type & EXT_CSD_CARD_TYPE_DDR_52;
+        err = mmc_select_timing(card);
+        if (err)
+                goto free_card;
 
-        /*
-         * Indicate HS200 SDR mode (if supported).
-         */
         if (mmc_card_hs200(card)) {
-                u32 ext_csd_bits;
-                u32 bus_width = card->host->ios.bus_width;
-
-                /*
-                 * For devices supporting HS200 mode, the bus width has
-                 * to be set before executing the tuning function. If
-                 * set before tuning, then device will respond with CRC
-                 * errors for responses on CMD line. So for HS200 the
-                 * sequence will be
-                 * 1. set bus width 4bit / 8 bit (1 bit not supported)
-                 * 2. switch to HS200 mode
-                 * 3. set the clock to > 52Mhz <=200MHz and
-                 * 4. execute tuning for HS200
-                 */
-                if (card->host->ops->execute_tuning) {
-                        mmc_host_clk_hold(card->host);
-                        err = card->host->ops->execute_tuning(card->host,
-                                MMC_SEND_TUNING_BLOCK_HS200);
-                        mmc_host_clk_release(card->host);
-                }
-                if (err) {
-                        pr_warning("%s: tuning execution failed\n",
-                                   mmc_hostname(card->host));
+                err = mmc_hs200_tuning(card);
+                if (err)
                         goto err;
-                }
-
-                ext_csd_bits = (bus_width == MMC_BUS_WIDTH_8) ?
-                                EXT_CSD_BUS_WIDTH_8 : EXT_CSD_BUS_WIDTH_4;
-        }
-
-        /*
-         * Activate wide bus and DDR (if supported).
-         */
-        if (!mmc_card_hs200(card) &&
-            (card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
-            (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
-                static unsigned ext_csd_bits[][2] = {
-                        { EXT_CSD_BUS_WIDTH_8, EXT_CSD_DDR_BUS_WIDTH_8 },
-                        { EXT_CSD_BUS_WIDTH_4, EXT_CSD_DDR_BUS_WIDTH_4 },
-                        { EXT_CSD_BUS_WIDTH_1, EXT_CSD_BUS_WIDTH_1 },
-                };
-                static unsigned bus_widths[] = {
-                        MMC_BUS_WIDTH_8,
-                        MMC_BUS_WIDTH_4,
-                        MMC_BUS_WIDTH_1
-                };
-                unsigned idx, bus_width = 0;
-
-                if (host->caps & MMC_CAP_8_BIT_DATA)
-                        idx = 0;
-                else
-                        idx = 1;
-                for (; idx < ARRAY_SIZE(bus_widths); idx++) {
-                        bus_width = bus_widths[idx];
-                        if (bus_width == MMC_BUS_WIDTH_1)
-                                ddr = 0; /* no DDR for 1-bit width */
-
-                        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
-                                         EXT_CSD_BUS_WIDTH,
-                                         ext_csd_bits[idx][0],
-                                         card->ext_csd.generic_cmd6_time);
-                        if (!err) {
-                                mmc_set_bus_width(card->host, bus_width);
-
-                                /*
-                                 * If controller can't handle bus width test,
-                                 * compare ext_csd previously read in 1 bit mode
-                                 * against ext_csd at new bus width
-                                 */
-                                if (!(host->caps & MMC_CAP_BUS_WIDTH_TEST))
-                                        err = mmc_compare_ext_csds(card,
-                                                bus_width);
-                                else
-                                        err = mmc_bus_test(card, bus_width);
-                                if (!err)
-                                        break;
-                        }
-                }
-
-                if (!err && ddr) {
-                        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
-                                         EXT_CSD_BUS_WIDTH,
-                                         ext_csd_bits[idx][1],
-                                         card->ext_csd.generic_cmd6_time);
-                }
-                if (err) {
-                        pr_warning("%s: switch to bus width %d ddr %d "
-                                "failed\n", mmc_hostname(card->host),
-                                1 << bus_width, ddr);
-                        goto free_card;
-                } else if (ddr) {
-                        /*
-                         * eMMC cards can support 3.3V to 1.2V i/o (vccq)
-                         * signaling.
-                         *
-                         * EXT_CSD_CARD_TYPE_DDR_1_8V means 3.3V or 1.8V vccq.
-                         *
-                         * 1.8V vccq at 3.3V core voltage (vcc) is not required
-                         * in the JEDEC spec for DDR.
-                         *
-                         * Do not force change in vccq since we are obviously
-                         * working and no change to vccq is needed.
-                         *
-                         * WARNING: eMMC rules are NOT the same as SD DDR
-                         */
-                        if (ddr & EXT_CSD_CARD_TYPE_DDR_1_2V) {
-                                err = __mmc_set_signal_voltage(host,
-                                        MMC_SIGNAL_VOLTAGE_120);
-                                if (err)
-                                        goto err;
-                        }
-                        mmc_set_timing(card->host, MMC_TIMING_MMC_DDR52);
-                        mmc_set_bus_width(card->host, bus_width);
+        } else if (mmc_card_hs(card)) {
+                /* Select the desired bus width optionally */
+                err = mmc_select_bus_width(card);
+                if (!IS_ERR_VALUE(err)) {
+                        err = mmc_select_hs_ddr(card);
+                        if (err)
+                                goto err;
                 }
         }