imx233: completely rework the sd driver

Change-Id: I456df0d9f5eaee435bdfd5a3f667055715e53d2a

3 files changed, 249 insertions, 128 deletions

diff --git a/firmware/target/arm/imx233/sd-imx233.c b/firmware/target/arm/imx233/sd-imx233.c
index 1e9d001bbd..d3c29ee5be 100644
--- a/firmware/target/arm/imx233/sd-imx233.c
+++ b/firmware/target/arm/imx233/sd-imx233.c
@@ -24,62 +24,107 @@
 #include "sdmmc.h"
 #include "ssp-imx233.h"
 #include "pinctrl-imx233.h"
+#include "partitions-imx233.h"
 #include "button-target.h"
 #include "fat.h"
 #include "disk.h"
 #include "usb.h"
 #include "debug.h"
 
-/**
- * This code assumes a single SD card slot
- */
-
+struct sd_config_t
+{
+    const char *name; /* name(for debug) */
+    int flags; /* flags */
+    int power_pin; /* power pin */
+    int power_delay; /* extra power up delay */
+    int ssp; /* associated ssp block */
+};
+
+/* flags */
+#define POWER_PIN       (1 << 0)
+#define POWER_INVERTED  (1 << 1)
+#define REMOVABLE       (1 << 2)
+#define DETECT_INVERTED (1 << 3)
+#define POWER_DELAY     (1 << 4)
+#define WINDOW          (1 << 5)
+
+#define PIN(bank,pin) ((bank) << 5 | (pin))
+#define PIN2BANK(v) ((v) >> 5)
+#define PIN2PIN(v) ((v) & 0x1f)
+
+struct sd_config_t sd_config[] =
+{
 #ifdef SANSA_FUZEPLUS
-#define SD_SSP      1
+    /* The Fuze+ uses pin #B0P8 for power */
+    {
+        .name = "microSD",
+        .flags = POWER_PIN | POWER_INVERTED | REMOVABLE,
+        .power_pin = PIN(0, 8),
+        .ssp = 1
+    },
 #else
-#error You need to configure the ssp to use
+#error You need to write the sd config!
 #endif
+};
 
-static tCardInfo card_info;
-static long sd_stack [(DEFAULT_STACK_SIZE*2 + 0x200)/sizeof(long)];
+#define SD_NUM_DRIVES   (sizeof(sd_config) / sizeof(sd_config[0]))
+
+#define SD_CONF(drive) sd_config[drive]
+#define SD_FLAGS(drive) SD_CONF(drive).flags
+#define SD_SSP(drive) SD_CONF(drive).ssp
+#define IF_FIRST_DRIVE(drive) if((drive) == 0)
+#define IF_SECOND_DRIVE(drive) if((drive) == 1)
+
+static tCardInfo card_info[SD_NUM_DRIVES];
+static long sd_stack[(DEFAULT_STACK_SIZE*2 + 0x200)/sizeof(long)];
 static struct mutex sd_mutex;
 static const char sd_thread_name[] = "sd";
 static struct event_queue sd_queue;
 static int sd_first_drive;
 static int last_disk_activity;
+static unsigned sd_window_start[SD_NUM_DRIVES];
+static unsigned sd_window_end[SD_NUM_DRIVES];
 
 static void sd_detect_callback(int ssp)
 {
-    (void)ssp;
     /* This is called only if the state was stable for 300ms - check state
      * and post appropriate event. */
-    if(imx233_ssp_sdmmc_detect(SD_SSP))
+    if(imx233_ssp_sdmmc_detect(ssp))
         queue_broadcast(SYS_HOTSWAP_INSERTED, 0);
     else
         queue_broadcast(SYS_HOTSWAP_EXTRACTED, 0);
-    imx233_ssp_sdmmc_setup_detect(SD_SSP, true, sd_detect_callback, false);
+    imx233_ssp_sdmmc_setup_detect(ssp, true, sd_detect_callback, false,
+        imx233_ssp_sdmmc_is_detect_inverted(ssp));
 }
 
-void sd_power(bool on)
+void sd_power(int drive, bool on)
 {
-    #ifdef SANSA_FUZEPLUS
-    /* The Fuze+ uses pin B0P8 for whatever reason, power ? */
-    imx233_pinctrl_acquire_pin(0, 8, "sd power");
-    imx233_set_pin_function(0, 8, PINCTRL_FUNCTION_GPIO);
-    imx233_enable_gpio_output(0, 8, true);
-    imx233_set_gpio_output(0, 8, !on);
-    /* disable pull ups when not needed to save power */
-    imx233_ssp_setup_ssp1_sd_mmc_pins(on, 4, PINCTRL_DRIVE_4mA, false);
-    #endif
+    /* power chip if needed */
+    if(SD_FLAGS(drive) & POWER_PIN)
+    {
+        int bank = PIN2BANK(SD_CONF(drive).power_pin);
+        int pin = PIN2PIN(SD_CONF(drive).power_pin);
+        imx233_pinctrl_acquire_pin(bank, pin, "sd power");
+        imx233_set_pin_function(bank, pin, PINCTRL_FUNCTION_GPIO);
+        imx233_enable_gpio_output(bank, pin, true);
+        if(SD_FLAGS(drive) & POWER_INVERTED)
+            imx233_set_gpio_output(bank, pin, !on);
+        else
+            imx233_set_gpio_output(bank, pin, on);
+    }
+    if(SD_FLAGS(drive) & POWER_DELAY)
+        sleep(SD_CONF(drive).power_delay);
+    /* setup pins, never use alternatives pin on SSP1 because these are force
+     * bus width >= 4 and SD cannot use more than 4 data lines. */
+    if(SD_SSP(drive) == 1)
+        imx233_ssp_setup_ssp1_sd_mmc_pins(on, 4, PINCTRL_DRIVE_4mA, false);
+    else
+        imx233_ssp_setup_ssp2_sd_mmc_pins(on, 4, PINCTRL_DRIVE_4mA);
 }
 
 void sd_enable(bool on)
 {
-    static int sd_enable = 2; /* 2 means not on and not off, for init purpose */
-    if(sd_enable == on)
-        return;
-
-    sd_enable = on;
+    (void) on;
 }
 
 #define MCI_NO_RESP     0
@@ -89,15 +134,15 @@ void sd_enable(bool on)
 #define MCI_NOCRC       (1<<3)
 #define MCI_BUSY        (1<<4)
 
-static bool send_cmd(uint8_t cmd, uint32_t arg, uint32_t flags, uint32_t *resp)
+static bool send_cmd(int drive, uint8_t cmd, uint32_t arg, uint32_t flags, uint32_t *resp)
 {
-    if((flags & MCI_ACMD) && !send_cmd(SD_APP_CMD, card_info.rca, MCI_RESP, resp))
+    if((flags & MCI_ACMD) && !send_cmd(drive, SD_APP_CMD, card_info[drive].rca, MCI_RESP, resp))
         return false;
 
     enum imx233_ssp_resp_t resp_type = (flags & MCI_LONG_RESP) ? SSP_LONG_RESP :
         (flags & MCI_RESP) ? SSP_SHORT_RESP : SSP_NO_RESP;
-    enum imx233_ssp_error_t ret = imx233_ssp_sd_mmc_transfer(SD_SSP, cmd, arg,
-        resp_type, NULL, 0, !!(flags & MCI_BUSY), false, resp);
+    enum imx233_ssp_error_t ret = imx233_ssp_sd_mmc_transfer(SD_SSP(drive), cmd,
+        arg, resp_type, NULL, 0, !!(flags & MCI_BUSY), false, resp);
     if(resp_type == SSP_LONG_RESP)
     {
         /* Our SD codes assume most significant word first, so reverse resp */
@@ -111,7 +156,7 @@ static bool send_cmd(uint8_t cmd, uint32_t arg, uint32_t flags, uint32_t *resp)
     return ret == SSP_SUCCESS;
 }
 
-static int sd_wait_for_tran_state(void)
+static int sd_wait_for_tran_state(int drive)
 {
     unsigned long response;
     unsigned int timeout = current_tick + 5*HZ;
@@ -119,7 +164,7 @@ static int sd_wait_for_tran_state(void)
     
     while (1)
     {
-        while(!send_cmd(SD_SEND_STATUS, card_info.rca, MCI_RESP, &response) && cmd_retry > 0)
+        while(!send_cmd(drive, SD_SEND_STATUS, card_info[drive].rca, MCI_RESP, &response) && cmd_retry > 0)
             cmd_retry--;
 
         if(cmd_retry <= 0)
@@ -135,33 +180,35 @@ static int sd_wait_for_tran_state(void)
     }
 }
 
-static int sd_init_card(void)
+static int sd_init_card(int drive)
 {
-    sd_enable(false);
-    sd_power(false);
-    sd_power(true);
-    sd_enable(true);
-    imx233_ssp_start(SD_SSP);
-    imx233_ssp_softreset(SD_SSP);
-    imx233_ssp_set_mode(SD_SSP, HW_SSP_CTRL1__SSP_MODE__SD_MMC);
+    /* sanity check against bad configuration of SD_NUM_DRIVES/NUM_DRIVES */
+    if((unsigned)drive >= SD_NUM_DRIVES)
+        panicf("drive >= SD_NUM_DRIVES in sd_init_card!");
+    int ssp = SD_SSP(drive);
+    sd_power(drive, false);
+    sd_power(drive, true);
+    imx233_ssp_start(ssp);
+    imx233_ssp_softreset(ssp);
+    imx233_ssp_set_mode(ssp, HW_SSP_CTRL1__SSP_MODE__SD_MMC);
     /* SSPCLK @ 96MHz
      * gives bitrate of 96000 / 240 / 1 = 400kHz */
-    imx233_ssp_set_timings(SD_SSP, 240, 0, 0xffff);
+    imx233_ssp_set_timings(ssp, 240, 0, 0xffff);
     
-    imx233_ssp_sd_mmc_power_up_sequence(SD_SSP);
-    imx233_ssp_set_bus_width(SD_SSP, 1);
-    imx233_ssp_set_block_size(SD_SSP, 9);
+    imx233_ssp_sd_mmc_power_up_sequence(ssp);
+    imx233_ssp_set_bus_width(ssp, 1);
+    imx233_ssp_set_block_size(ssp, 9);
 
-    card_info.rca = 0;
+    card_info[drive].rca = 0;
     bool sd_v2 = false;
     uint32_t resp;
     long init_timeout;
     /* go to idle state */
-    if(!send_cmd(SD_GO_IDLE_STATE, 0, MCI_NO_RESP, NULL))
+    if(!send_cmd(drive, SD_GO_IDLE_STATE, 0, MCI_NO_RESP, NULL))
         return -1;
     /* CMD8 Check for v2 sd card.  Must be sent before using ACMD41
        Non v2 cards will not respond to this command */
-    if(send_cmd(SD_SEND_IF_COND, 0x1AA, MCI_RESP, &resp))
+    if(send_cmd(drive, SD_SEND_IF_COND, 0x1AA, MCI_RESP, &resp))
         if((resp & 0xFFF) == 0x1AA)
             sd_v2 = true;
     /* timeout for initialization is 1sec, from SD Specification 2.00 */
@@ -173,67 +220,84 @@ static int sd_init_card(void)
             return -2;
 
         /* ACMD41 For v2 cards set HCS bit[30] & send host voltage range to all */
-        if(!send_cmd(SD_APP_OP_COND, (0x00FF8000 | (sd_v2 ? 1<<30 : 0)),
-                MCI_ACMD|MCI_NOCRC|MCI_RESP, &card_info.ocr))
+        if(!send_cmd(drive, SD_APP_OP_COND, (0x00FF8000 | (sd_v2 ? 1<<30 : 0)),
+                MCI_ACMD|MCI_NOCRC|MCI_RESP, &card_info[drive].ocr))
             return -100;
-    } while(!(card_info.ocr & (1<<31)));
+    } while(!(card_info[drive].ocr & (1<<31)));
 
     /* CMD2 send CID */
-    if(!send_cmd(SD_ALL_SEND_CID, 0, MCI_RESP|MCI_LONG_RESP, card_info.cid))
+    if(!send_cmd(drive, SD_ALL_SEND_CID, 0, MCI_RESP|MCI_LONG_RESP, card_info[drive].cid))
         return -3;
 
     /* CMD3 send RCA */
-    if(!send_cmd(SD_SEND_RELATIVE_ADDR, 0, MCI_RESP, &card_info.rca))
+    if(!send_cmd(drive, SD_SEND_RELATIVE_ADDR, 0, MCI_RESP, &card_info[drive].rca))
         return -4;
 
     /* Try to switch V2 cards to HS timings, non HS seem to ignore this */
     if(sd_v2)
     {
         /*  CMD7 w/rca: Select card to put it in TRAN state */
-        if(!send_cmd(SD_SELECT_CARD, card_info.rca, MCI_RESP, NULL))
+        if(!send_cmd(drive, SD_SELECT_CARD, card_info[drive].rca, MCI_RESP, NULL))
             return -5;
 
-        if(sd_wait_for_tran_state())
+        if(sd_wait_for_tran_state(drive))
             return -6;
 
         /* CMD6 */
-        if(!send_cmd(SD_SWITCH_FUNC, 0x80fffff1, MCI_NO_RESP, NULL))
+        if(!send_cmd(drive, SD_SWITCH_FUNC, 0x80fffff1, MCI_NO_RESP, NULL))
             return -7;
         sleep(HZ/10);
 
         /*  go back to STBY state so we can read csd */
         /*  CMD7 w/rca=0:  Deselect card to put it in STBY state */
-        if(!send_cmd(SD_DESELECT_CARD, 0, MCI_NO_RESP, NULL))
+        if(!send_cmd(drive, SD_DESELECT_CARD, 0, MCI_NO_RESP, NULL))
             return -8;
     }
 
     /* CMD9 send CSD */
-    if(!send_cmd(SD_SEND_CSD, card_info.rca, MCI_RESP|MCI_LONG_RESP, card_info.csd))
+    if(!send_cmd(drive, SD_SEND_CSD, card_info[drive].rca, MCI_RESP|MCI_LONG_RESP, card_info[drive].csd))
         return -9;
 
-    sd_parse_csd(&card_info);
+    sd_parse_csd(&card_info[drive]);
 
     /* SSPCLK @ 96MHz
      * gives bitrate of 96 / 4 / 1 = 24MHz */
-    imx233_ssp_set_timings(SD_SSP, 4, 0, 0xffff);
+    imx233_ssp_set_timings(ssp, 4, 0, 0xffff);
 
     /* CMD7 w/rca: Select card to put it in TRAN state */
-    if(!send_cmd(SD_SELECT_CARD, card_info.rca, MCI_RESP, &resp))
+    if(!send_cmd(drive, SD_SELECT_CARD, card_info[drive].rca, MCI_RESP, &resp))
         return -12;
-    if(sd_wait_for_tran_state() < 0)
+    if(sd_wait_for_tran_state(drive) < 0)
         return -13;
 
     /* ACMD6: set bus width to 4-bit */
-    if(!send_cmd(SD_SET_BUS_WIDTH, 2, MCI_RESP|MCI_ACMD, &resp))
+    if(!send_cmd(drive, SD_SET_BUS_WIDTH, 2, MCI_RESP|MCI_ACMD, &resp))
         return -15;
     /* ACMD42: disconnect the pull-up resistor on CD/DAT3 */
-    if(!send_cmd(SD_SET_CLR_CARD_DETECT, 0, MCI_RESP|MCI_ACMD, &resp))
+    if(!send_cmd(drive, SD_SET_CLR_CARD_DETECT, 0, MCI_RESP|MCI_ACMD, &resp))
         return -17;
 
     /* Switch to 4-bit */
-    imx233_ssp_set_bus_width(SD_SSP, 4);
+    imx233_ssp_set_bus_width(ssp, 4);
 
-    card_info.initialized = 1;
+    card_info[drive].initialized = 1;
+
+    /* compute window */
+    sd_window_start[drive] = 0;
+    sd_window_end[drive] = card_info[drive].numblocks;
+    if((SD_FLAGS(drive) & WINDOW) && imx233_partitions_is_window_enabled())
+    {
+        /* WARNING: sd_first_drive is not set at this point */
+        uint8_t mbr[512];
+        int ret = sd_read_sectors(IF_MD2(drive,) 0, 1, mbr);
+        if(ret)
+            panicf("Cannot read MBR: %d", ret);
+        ret = imx233_partitions_compute_window(mbr, &sd_window_start[drive],
+            &sd_window_end[drive]);
+        if(ret)
+            panicf("cannot compute partitions window: %d", ret);
+        card_info[drive].numblocks = sd_window_end[drive] - sd_window_start[drive];
+    }
     
     return 0;
 }
@@ -253,45 +317,51 @@ static void sd_thread(void)
         case SYS_HOTSWAP_EXTRACTED:
         {
             int microsd_init = 1;
-            fat_lock();          /* lock-out FAT activity first -
-                                    prevent deadlocking via disk_mount that
-                                    would cause a reverse-order attempt with
-                                    another thread */
-            mutex_lock(&sd_mutex); /* lock-out card activity - direct calls
-                                    into driver that bypass the fat cache */
-
-            /* We now have exclusive control of fat cache and sd */
-
-            disk_unmount(sd_first_drive);     /* release "by force", ensure file
-                                    descriptors aren't leaked and any busy
-                                    ones are invalid if mounting */
-            /* Force card init for new card, re-init for re-inserted one or
-             * clear if the last attempt to init failed with an error. */
-            card_info.initialized = 0;
-
-            if(ev.id == SYS_HOTSWAP_INSERTED)
+             /* lock-out FAT activity first -
+              * prevent deadlocking via disk_mount that
+              * would cause a reverse-order attempt with
+              * another thread */
+            fat_lock();
+            /* lock-out card activity - direct calls
+             * into driver that bypass the fat cache */
+            mutex_lock(&sd_mutex);
+
+            /* We now have exclusive control of fat cache and sd.
+             * Release "by force", ensure file
+             * descriptors aren't leaked and any busy
+             * ones are invalid if mounting. */
+            for(unsigned drive = 0; drive < SD_NUM_DRIVES; drive++)
             {
-                microsd_init = sd_init_card();
-                if(microsd_init < 0) /* initialisation failed */
-                    panicf("microSD init failed : %d", microsd_init);
-
-                microsd_init = disk_mount(sd_first_drive); /* 0 if fail */
+                /* Skip non-removable drivers */
+                if(!sd_removable(drive))
+                    continue;
+                disk_unmount(sd_first_drive + drive);
+                /* Force card init for new card, re-init for re-inserted one or
+                * clear if the last attempt to init failed with an error. */
+                card_info[drive].initialized = 0;
+
+                if(ev.id == SYS_HOTSWAP_INSERTED)
+                {
+                    microsd_init = sd_init_card(drive);
+                    if(microsd_init < 0) /* initialisation failed */
+                        panicf("%s init failed : %d", SD_CONF(drive).name, microsd_init);
+
+                    microsd_init = disk_mount(sd_first_drive + drive); /* 0 if fail */
+                }
+                /*
+                * Mount succeeded, or this was an EXTRACTED event,
+                * in both cases notify the system about the changed filesystems
+                */
+                if(microsd_init)
+                    queue_broadcast(SYS_FS_CHANGED, 0);
             }
-            /*
-             * Mount succeeded, or this was an EXTRACTED event,
-             * in both cases notify the system about the changed filesystems
-             */
-            if(microsd_init)
-                queue_broadcast(SYS_FS_CHANGED, 0);
-
-            sd_enable(false);
             /* Access is now safe */
             mutex_unlock(&sd_mutex);
             fat_unlock();
             break;
         }
         case SYS_TIMEOUT:
-            if(!TIME_BEFORE(current_tick, last_disk_activity+(3*HZ)))
+            if(!TIME_BEFORE(current_tick, last_disk_activity +3 * HZ))
                 sd_enable(false);
             break;
         case SYS_USB_CONNECTED:
@@ -309,8 +379,13 @@ int sd_init(void)
     queue_init(&sd_queue, true);
     create_thread(sd_thread, sd_stack, sizeof(sd_stack), 0,
             sd_thread_name IF_PRIO(, PRIORITY_USER_INTERFACE) IF_COP(, CPU));
-    sd_enable(false);
-    imx233_ssp_sdmmc_setup_detect(SD_SSP, true, sd_detect_callback, false);
+
+    for(unsigned drive = 0; drive < SD_NUM_DRIVES; drive++)
+    {
+        if(SD_FLAGS(drive) & REMOVABLE)
+            imx233_ssp_sdmmc_setup_detect(SD_SSP(drive), true, sd_detect_callback,
+                false, SD_FLAGS(drive) & DETECT_INVERTED);
+    }
     
     return 0;
 }
@@ -324,21 +399,28 @@ static int transfer_sectors(IF_MD2(int drive,) unsigned long start, int count, v
     last_disk_activity = current_tick;
 
     mutex_lock(&sd_mutex);
-    sd_enable(true);
 
-    if(card_info.initialized <= 0)
+    if(card_info[drive].initialized <= 0)
     {
-        ret = sd_init_card();
-        if(card_info.initialized <= 0)
+        ret = sd_init_card(drive);
+        if(card_info[drive].initialized <= 0)
             goto Lend;
     }
+
+    /* check window */
+    start += sd_window_start[drive];
+    if((start + count) > sd_window_end[drive])
+    {
+        ret = -201;
+        goto Lend;
+    }
     
-    if(!send_cmd(SD_SELECT_CARD, card_info.rca, MCI_NO_RESP, NULL))
+    if(!send_cmd(drive, SD_SELECT_CARD, card_info[drive].rca, MCI_NO_RESP, NULL))
     {
         ret = -20;
         goto Lend;
     }
-    ret = sd_wait_for_tran_state();
+    ret = sd_wait_for_tran_state(drive);
     if(ret < 0)
         goto Ldeselect;
     while(count != 0)
@@ -346,13 +428,14 @@ static int transfer_sectors(IF_MD2(int drive,) unsigned long start, int count, v
         int this_count = MIN(count, IMX233_MAX_SSP_XFER_SIZE / 512);
         /* Set bank_start to the correct unit (blocks or bytes) */
         int bank_start = start;
-        if(!(card_info.ocr & (1<<30)))   /* not SDHC */
+        if(!(card_info[drive].ocr & (1<<30)))   /* not SDHC */
             bank_start *= SD_BLOCK_SIZE;
-        ret = imx233_ssp_sd_mmc_transfer(SD_SSP, read ? SD_READ_MULTIPLE_BLOCK : SD_WRITE_MULTIPLE_BLOCK,
+        ret = imx233_ssp_sd_mmc_transfer(SD_SSP(drive),
+            read ? SD_READ_MULTIPLE_BLOCK : SD_WRITE_MULTIPLE_BLOCK,
             bank_start, SSP_SHORT_RESP, buf, this_count, false, read, &resp);
         if(ret != SSP_SUCCESS)
             break;
-        if(!send_cmd(SD_STOP_TRANSMISSION, 0, MCI_RESP|MCI_BUSY, &resp))
+        if(!send_cmd(drive, SD_STOP_TRANSMISSION, 0, MCI_RESP|MCI_BUSY, &resp))
         {
             ret = -15;
             break;
@@ -364,51 +447,48 @@ static int transfer_sectors(IF_MD2(int drive,) unsigned long start, int count, v
 
     Ldeselect:
     /*  CMD7 w/rca =0 : deselects card & puts it in STBY state */
-    if(!send_cmd(SD_DESELECT_CARD, 0, MCI_NO_RESP, NULL))
+    if(!send_cmd(drive, SD_DESELECT_CARD, 0, MCI_NO_RESP, NULL))
         ret = -23;
     Lend:
     mutex_unlock(&sd_mutex);
     return ret;
 }
 
-int sd_read_sectors(IF_MD2(int drive,) unsigned long start, int count,
-                     void* buf)
+int sd_read_sectors(IF_MD2(int drive,) unsigned long start, int count, void* buf)
 {
     return transfer_sectors(IF_MD2(drive,) start, count, buf, true);
 }
 
-int sd_write_sectors(IF_MD2(int drive,) unsigned long start, int count,
-                     const void* buf)
+int sd_write_sectors(IF_MD2(int drive,) unsigned long start, int count, const void* buf)
 {
     return transfer_sectors(IF_MD2(drive,) start, count, (void *)buf, false);
 }
 
 tCardInfo *card_get_info_target(int card_no)
 {
-    (void)card_no;
-    return &card_info;
+    return &card_info[card_no];
 }
 
 int sd_num_drives(int first_drive)
 {
     sd_first_drive = first_drive;
-    return 1;
+    return SD_NUM_DRIVES;
 }
 
-bool sd_present(IF_MD(int drive))
+bool sd_present(IF_MV_NONVOID(int drive))
 {
-    IF_MD((void) drive);
-    return imx233_ssp_sdmmc_detect(SD_SSP);
+    if(SD_FLAGS(drive) & REMOVABLE)
+        return imx233_ssp_sdmmc_detect(SD_SSP(drive));
+    else
+        return true;
 }
 
-bool sd_removable(IF_MD(int drive))
+bool sd_removable(IF_MV_NONVOID(int drive))
 {
-    IF_MD((void) drive);
-    return true;
+    return SD_FLAGS(drive) & REMOVABLE;
 }
 
 long sd_last_disk_activity(void)
 {
     return last_disk_activity;
 }
-
diff --git a/firmware/target/arm/imx233/ssp-imx233.c b/firmware/target/arm/imx233/ssp-imx233.c
index 1dd2d767ba..21dcba67aa 100644
--- a/firmware/target/arm/imx233/ssp-imx233.c
+++ b/firmware/target/arm/imx233/ssp-imx233.c
@@ -28,6 +28,13 @@
 #include "pinctrl-imx233.h"
 #include "dma-imx233.h"
 
+/* for debug purpose */
+#if 0
+#define ASSERT_SSP(ssp) if(ssp < 1 || ssp > 2) panicf("ssp=%d in %s", ssp, __func__);
+#else
+#define ASSERT_SSP(ssp)
+#endif
+
 /* Used for DMA */
 struct ssp_dma_command_t
 {
@@ -46,6 +53,7 @@ static struct ssp_dma_command_t ssp_dma_cmd[2];
 static uint32_t ssp_bus_width[2];
 static unsigned ssp_log_block_size[2];
 static ssp_detect_cb_t ssp_detect_cb[2];
+static bool ssp_detect_invert[2];
 
 void INT_SSP(int ssp)
 {
@@ -93,6 +101,7 @@ void imx233_ssp_init(void)
 
 void imx233_ssp_start(int ssp)
 {
+    ASSERT_SSP(ssp)
     if(ssp_in_use[ssp - 1])
         return;
     ssp_in_use[ssp - 1] = true;
@@ -117,6 +126,7 @@ void imx233_ssp_start(int ssp)
 
 void imx233_ssp_stop(int ssp)
 {
+    ASSERT_SSP(ssp)
     if(!ssp_in_use[ssp - 1])
         return;
     ssp_in_use[ssp - 1] = false;
@@ -135,11 +145,13 @@ void imx233_ssp_stop(int ssp)
 
 void imx233_ssp_softreset(int ssp)
 {
+    ASSERT_SSP(ssp)
     imx233_reset_block(&HW_SSP_CTRL0(ssp));
 }
 
 void imx233_ssp_set_timings(int ssp, int divide, int rate, int timeout)
 {
+    ASSERT_SSP(ssp)
     HW_SSP_TIMING(ssp) = divide << HW_SSP_TIMING__CLOCK_DIVIDE_BP | rate |
         timeout << HW_SSP_TIMING__CLOCK_TIMEOUT_BP;
 }
@@ -209,6 +221,7 @@ void imx233_ssp_setup_ssp2_sd_mmc_pins(bool enable_pullups, unsigned bus_width,
 
 void imx233_ssp_set_mode(int ssp, unsigned mode)
 {
+    ASSERT_SSP(ssp)
     switch(mode)
     {
         case HW_SSP_CTRL1__SSP_MODE__SD_MMC:
@@ -226,6 +239,7 @@ void imx233_ssp_set_mode(int ssp, unsigned mode)
 
 void imx233_ssp_set_bus_width(int ssp, unsigned width)
 {
+    ASSERT_SSP(ssp)
     switch(width)
     {
         case 1: ssp_bus_width[ssp - 1] = HW_SSP_CTRL0__BUS_WIDTH__ONE_BIT; break;
@@ -236,6 +250,7 @@ void imx233_ssp_set_bus_width(int ssp, unsigned width)
 
 void imx233_ssp_set_block_size(int ssp, unsigned log_block_size)
 {
+    ASSERT_SSP(ssp)
     ssp_log_block_size[ssp - 1] = log_block_size;
 }
 
@@ -243,6 +258,7 @@ enum imx233_ssp_error_t imx233_ssp_sd_mmc_transfer(int ssp, uint8_t cmd,
     uint32_t cmd_arg, enum imx233_ssp_resp_t resp, void *buffer, unsigned block_count,
     bool wait4irq, bool read, uint32_t *resp_ptr)
 {
+    ASSERT_SSP(ssp)
     mutex_lock(&ssp_mutex[ssp - 1]);
     /* Enable all interrupts */
     imx233_icoll_enable_interrupt(INT_SRC_SSP_DMA(ssp), true);
@@ -312,6 +328,7 @@ enum imx233_ssp_error_t imx233_ssp_sd_mmc_transfer(int ssp, uint8_t cmd,
 
 void imx233_ssp_sd_mmc_power_up_sequence(int ssp)
 {
+    ASSERT_SSP(ssp)
     __REG_CLR(HW_SSP_CMD0(ssp)) = HW_SSP_CMD0__SLOW_CLKING_EN;
     __REG_SET(HW_SSP_CMD0(ssp)) = HW_SSP_CMD0__CONT_CLKING_EN;
     mdelay(1);
@@ -320,6 +337,7 @@ void imx233_ssp_sd_mmc_power_up_sequence(int ssp)
 
 static int ssp_detect_oneshot_callback(int ssp)
 {
+    ASSERT_SSP(ssp)
     if(ssp_detect_cb[ssp - 1])
         ssp_detect_cb[ssp - 1](ssp);
 
@@ -348,11 +366,14 @@ static void detect_irq(int bank, int pin)
         timeout_register(&ssp2_detect_oneshot, ssp2_detect_oneshot_callback, (3*HZ/10), 0);
 }
 
-void imx233_ssp_sdmmc_setup_detect(int ssp, bool enable, ssp_detect_cb_t fn, bool first_time)
+void imx233_ssp_sdmmc_setup_detect(int ssp, bool enable, ssp_detect_cb_t fn,
+    bool first_time, bool invert)
 {
+    ASSERT_SSP(ssp)
     int bank = ssp == 1 ? 2 : 0;
     int pin = ssp == 1 ? 1 : 19;
     ssp_detect_cb[ssp - 1] = fn;
+    ssp_detect_invert[ssp - 1] = invert;
     if(enable)
     {
         imx233_pinctrl_acquire_pin(bank, pin, ssp == 1 ? "ssp1 detect" : "ssp2 detect");
@@ -361,10 +382,23 @@ void imx233_ssp_sdmmc_setup_detect(int ssp, bool enable, ssp_detect_cb_t fn, boo
     }
     if(first_time && imx233_ssp_sdmmc_detect(ssp))
         detect_irq(bank, pin);
-    imx233_setup_pin_irq(bank, pin, enable, true, !imx233_ssp_sdmmc_detect(ssp), detect_irq);
+    imx233_setup_pin_irq(bank, pin, enable, true, !imx233_ssp_sdmmc_detect_raw(ssp), detect_irq);
 }
 
-bool imx233_ssp_sdmmc_detect(int ssp)
+bool imx233_ssp_sdmmc_is_detect_inverted(int ssp)
+{
+    ASSERT_SSP(ssp)
+    return ssp_detect_invert[ssp - 1];
+}
+
+bool imx233_ssp_sdmmc_detect_raw(int ssp)
 {
+    ASSERT_SSP(ssp)
     return !!(HW_SSP_STATUS(ssp) & HW_SSP_STATUS__CARD_DETECT);
 }
+
+bool imx233_ssp_sdmmc_detect(int ssp)
+{
+    ASSERT_SSP(ssp)
+    return imx233_ssp_sdmmc_detect_raw(ssp) != ssp_detect_invert[ssp - 1];
+}
diff --git a/firmware/target/arm/imx233/ssp-imx233.h b/firmware/target/arm/imx233/ssp-imx233.h
index a463c04a20..c168d5997c 100644
--- a/firmware/target/arm/imx233/ssp-imx233.h
+++ b/firmware/target/arm/imx233/ssp-imx233.h
@@ -7,7 +7,7 @@
  *                     \/            \/     \/    \/            \/
  * $Id$
  *
- * Copyright (C) 2011 by amaury Pouly
+ * Copyright (C) 2011 by Amaury Pouly
  *
  * Based on Rockbox iriver bootloader by Linus Nielsen Feltzing
  * and the ipodlinux bootloader by Daniel Palffy and Bernard Leach
@@ -170,8 +170,15 @@ void imx233_ssp_setup_ssp2_sd_mmc_pins(bool enable_pullups, unsigned bus_width,
 /* after callback is fired, imx233_ssp_sdmmc_setup_detect needs to be called
  * to enable detection again. If first_time is true, the callback will
  * be called if the sd card is inserted when the function is called, otherwise
- * it will be called on the next insertion change. */
-void imx233_ssp_sdmmc_setup_detect(int ssp, bool enable, ssp_detect_cb_t fn, bool first_time);
+ * it will be called on the next insertion change.
+ * By default, sd_detect=1 means sd inserted; invert reverses this behaviour */
+void imx233_ssp_sdmmc_setup_detect(int ssp, bool enable, ssp_detect_cb_t fn,
+    bool first_time, bool invert);
+/* needs prior setup with imx233_ssp_sdmmc_setup_detect */
+bool imx233_ssp_sdmmc_is_detect_inverted(int spp);
+/* raw value of the detect pin */
+bool imx233_ssp_sdmmc_detect_raw(int ssp);
+/* corrected value given the invert setting */
 bool imx233_ssp_sdmmc_detect(int ssp);
 /* SD/MMC requires that the card be provided the clock during an init sequence of
  * at least 1msec (or 74 clocks). Does NOT touch the clock so it has to be correct. */