sdio: recognize io card without powercycle

SDIO Simplified Specification V2.00 states that it is strongly recommended
that the host executes either a power reset or issues a CMD52 (I/O Reset)
to re-initialize an I/O only card or the I/O portion of a combo card.
Additionally, the CMD52 must be issued first because it cannot be issued
after a CMD0.

With this patch the Nintendo Wii SDIO-based WLAN card is detected after a
system reset, without requiring a complete system powercycle.

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index f4b97d3..3168ebd 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1089,6 +1089,7 @@ void mmc_rescan(struct work_struct *work)
        mmc_claim_host(host);
 
        mmc_power_up(host);
+       sdio_reset(host);
        mmc_go_idle(host);
 
        mmc_send_if_cond(host, host->ocr_avail);

diff --git a/drivers/mmc/core/sdio_ops.c b/drivers/mmc/core/sdio_ops.c
index 4eb7825..dea36d9 100644 (file)
--- a/drivers/mmc/core/sdio_ops.c
+++ b/drivers/mmc/core/sdio_ops.c
@@ -67,13 +67,13 @@ int mmc_send_io_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
        return err;
 }
 
-int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
-       unsigned addr, u8 in, u8* out)
+static int mmc_io_rw_direct_host(struct mmc_host *host, int write, unsigned fn,
+       unsigned addr, u8 in, u8 *out)
 {
        struct mmc_command cmd;
        int err;
 
-       BUG_ON(!card);
+       BUG_ON(!host);
        BUG_ON(fn > 7);
 
        /* sanity check */
@@ -90,11 +90,11 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
        cmd.arg |= in;
        cmd.flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_AC;
 
-       err = mmc_wait_for_cmd(card->host, &cmd, 0);
+       err = mmc_wait_for_cmd(host, &cmd, 0);
        if (err)
                return err;
 
-       if (mmc_host_is_spi(card->host)) {
+       if (mmc_host_is_spi(host)) {
                /* host driver already reported errors */
        } else {
                if (cmd.resp[0] & R5_ERROR)
@@ -106,7 +106,7 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
        }
 
        if (out) {
-               if (mmc_host_is_spi(card->host))
+               if (mmc_host_is_spi(host))
                        *out = (cmd.resp[0] >> 8) & 0xFF;
                else
                        *out = cmd.resp[0] & 0xFF;
@@ -115,6 +115,13 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
        return 0;
 }
 
+int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
+       unsigned addr, u8 in, u8 *out)
+{
+       BUG_ON(!card);
+       return mmc_io_rw_direct_host(card->host, write, fn, addr, in, out);
+}
+
 int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
        unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz)
 {
@@ -182,3 +189,20 @@ int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
        return 0;
 }
 
+int sdio_reset(struct mmc_host *host)
+{
+       int ret;
+       u8 abort;
+
+       /* SDIO Simplified Specification V2.0, 4.4 Reset for SDIO */
+
+       ret = mmc_io_rw_direct_host(host, 0, 0, SDIO_CCCR_ABORT, 0, &abort);
+       if (ret)
+               abort = 0x08;
+       else
+               abort |= 0x08;
+
+       ret = mmc_io_rw_direct_host(host, 1, 0, SDIO_CCCR_ABORT, abort, NULL);
+       return ret;
+}
+

diff --git a/drivers/mmc/core/sdio_ops.h b/drivers/mmc/core/sdio_ops.h
index e2e74b0..12a4d3a 100644 (file)
--- a/drivers/mmc/core/sdio_ops.h
+++ b/drivers/mmc/core/sdio_ops.h
@@ -17,6 +17,7 @@ int mmc_io_rw_direct(struct mmc_card *card, int write, unsigned fn,
        unsigned addr, u8 in, u8* out);
 int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn,
        unsigned addr, int incr_addr, u8 *buf, unsigned blocks, unsigned blksz);
+int sdio_reset(struct mmc_host *host);
 
 #endif