ANDROID: mmc: Add new API call 'sdio_reset_comm' for resetting communication with an SDIO device

Signed-off-by: San Mehat <san@android.com>
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index c8a5e71..5c51e03 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -1215,3 +1215,60 @@
 	return err;
 }
 
+int sdio_reset_comm(struct mmc_card *card)
+{
+	struct mmc_host *host = card->host;
+	u32 ocr;
+	int err;
+
+	printk("%s():\n", __func__);
+	mmc_go_idle(host);
+
+	mmc_set_clock(host, host->f_min);
+
+	err = mmc_send_io_op_cond(host, 0, &ocr);
+	if (err)
+		goto err;
+
+	host->ocr = mmc_select_voltage(host, ocr);
+	if (!host->ocr) {
+		err = -EINVAL;
+		goto err;
+	}
+
+	err = mmc_send_io_op_cond(host, host->ocr, &ocr);
+	if (err)
+		goto err;
+
+	if (mmc_host_is_spi(host)) {
+		err = mmc_spi_set_crc(host, use_spi_crc);
+		if (err)
+		goto err;
+	}
+
+	if (!mmc_host_is_spi(host)) {
+		err = mmc_send_relative_addr(host, &card->rca);
+		if (err)
+			goto err;
+		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
+	}
+	if (!mmc_host_is_spi(host)) {
+		err = mmc_select_card(card);
+		if (err)
+			goto err;
+	}
+
+	mmc_set_clock(host, card->cis.max_dtr);
+	err = sdio_enable_wide(card);
+	if (err)
+		goto err;
+
+	return 0;
+ err:
+	printk("%s: Error resetting SDIO communications (%d)\n",
+	       mmc_hostname(host), err);
+	return err;
+}
+EXPORT_SYMBOL(sdio_reset_comm);
+
+