1 files changed, 180 insertions, 20 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index b27b94078c2..ec769490300 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -24,6 +24,8 @@
 #include <linux/regulator/consumer.h>
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
+#include <linux/fault-inject.h>
+#include <linux/random.h>
 
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -83,6 +85,43 @@ static void mmc_flush_scheduled_work(void)
 	flush_workqueue(workqueue);
 }
 
+#ifdef CONFIG_FAIL_MMC_REQUEST
+
+/*
+ * Internal function. Inject random data errors.
+ * If mmc_data is NULL no errors are injected.
+ */
+static void mmc_should_fail_request(struct mmc_host *host,
+				    struct mmc_request *mrq)
+{
+	struct mmc_command *cmd = mrq->cmd;
+	struct mmc_data *data = mrq->data;
+	static const int data_errors[] = {
+		-ETIMEDOUT,
+		-EILSEQ,
+		-EIO,
+	};
+
+	if (!data)
+		return;
+
+	if (cmd->error || data->error ||
+	    !should_fail(&host->fail_mmc_request, data->blksz * data->blocks))
+		return;
+
+	data->error = data_errors[random32() % ARRAY_SIZE(data_errors)];
+	data->bytes_xfered = (random32() % (data->bytes_xfered >> 9)) << 9;
+}
+
+#else /* CONFIG_FAIL_MMC_REQUEST */
+
+static inline void mmc_should_fail_request(struct mmc_host *host,
+					   struct mmc_request *mrq)
+{
+}
+
+#endif /* CONFIG_FAIL_MMC_REQUEST */
+
 /**
  *	mmc_request_done - finish processing an MMC request
  *	@host: MMC host which completed request
@@ -102,13 +141,15 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
 	}
 
 	if (err && cmd->retries) {
-		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
-			mmc_hostname(host), cmd->opcode, err);
-
-		cmd->retries--;
-		cmd->error = 0;
-		host->ops->request(host, mrq);
+		/*
+		 * Request starter must handle retries - see
+		 * mmc_wait_for_req_done().
+		 */
+		if (mrq->done)
+			mrq->done(mrq);
 	} else {
+		mmc_should_fail_request(host, mrq);
+
 		led_trigger_event(host->led, LED_OFF);
 
 		pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
@@ -212,7 +253,21 @@ static void __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
 static void mmc_wait_for_req_done(struct mmc_host *host,
 				  struct mmc_request *mrq)
 {
-	wait_for_completion(&mrq->completion);
+	struct mmc_command *cmd;
+
+	while (1) {
+		wait_for_completion(&mrq->completion);
+
+		cmd = mrq->cmd;
+		if (!cmd->error || !cmd->retries)
+			break;
+
+		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
+			 mmc_hostname(host), cmd->opcode, cmd->error);
+		cmd->retries--;
+		cmd->error = 0;
+		host->ops->request(host, mrq);
+	}
 }
 
 /**
@@ -279,8 +334,14 @@ struct mmc_async_req *mmc_start_req(struct mmc_host *host,
 		mmc_wait_for_req_done(host, host->areq->mrq);
 		err = host->areq->err_check(host->card, host->areq);
 		if (err) {
+			/* post process the completed failed request */
 			mmc_post_req(host, host->areq->mrq, 0);
 			if (areq)
+				/*
+				 * Cancel the new prepared request, because
+				 * it can't run until the failed
+				 * request has been properly handled.
+				 */
 				mmc_post_req(host, areq->mrq, -EINVAL);
 
 			host->areq = NULL;
@@ -330,7 +391,7 @@ EXPORT_SYMBOL(mmc_wait_for_req);
  */
 int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int retries)
 {
-	struct mmc_request mrq = {0};
+	struct mmc_request mrq = {NULL};
 
 	WARN_ON(!host->claimed);
 
@@ -1119,13 +1180,11 @@ static void mmc_power_up(struct mmc_host *host)
 		bit = fls(host->ocr_avail) - 1;
 
 	host->ios.vdd = bit;
-	if (mmc_host_is_spi(host)) {
+	if (mmc_host_is_spi(host))
 		host->ios.chip_select = MMC_CS_HIGH;
-		host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
-	} else {
+	else
 		host->ios.chip_select = MMC_CS_DONTCARE;
-		host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
-	}
+	host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
 	host->ios.power_mode = MMC_POWER_UP;
 	host->ios.bus_width = MMC_BUS_WIDTH_1;
 	host->ios.timing = MMC_TIMING_LEGACY;
@@ -1151,7 +1210,7 @@ static void mmc_power_up(struct mmc_host *host)
 	mmc_host_clk_release(host);
 }
 
-static void mmc_power_off(struct mmc_host *host)
+void mmc_power_off(struct mmc_host *host)
 {
 	mmc_host_clk_hold(host);
 
@@ -1173,6 +1232,13 @@ static void mmc_power_off(struct mmc_host *host)
 	host->ios.timing = MMC_TIMING_LEGACY;
 	mmc_set_ios(host);
 
+	/*
+	 * Some configurations, such as the 802.11 SDIO card in the OLPC
+	 * XO-1.5, require a short delay after poweroff before the card
+	 * can be successfully turned on again.
+	 */
+	mmc_delay(1);
+
 	mmc_host_clk_release(host);
 }
 
@@ -1241,8 +1307,7 @@ void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops)
 }
 
 /*
- * Remove the current bus handler from a host. Assumes that there are
- * no interesting cards left, so the bus is powered down.
+ * Remove the current bus handler from a host.
  */
 void mmc_detach_bus(struct mmc_host *host)
 {
@@ -1259,8 +1324,6 @@ void mmc_detach_bus(struct mmc_host *host)
 
 	spin_unlock_irqrestore(&host->lock, flags);
 
-	mmc_power_off(host);
-
 	mmc_bus_put(host);
 }
 
@@ -1480,7 +1543,7 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from,
 	if (err) {
 		printk(KERN_ERR "mmc_erase: group start error %d, "
 		       "status %#x\n", err, cmd.resp[0]);
-		err = -EINVAL;
+		err = -EIO;
 		goto out;
 	}
 
@@ -1495,7 +1558,7 @@ static int mmc_do_erase(struct mmc_card *card, unsigned int from,
 	if (err) {
 		printk(KERN_ERR "mmc_erase: group end error %d, status %#x\n",
 		       err, cmd.resp[0]);
-		err = -EINVAL;
+		err = -EIO;
 		goto out;
 	}
 
@@ -1727,6 +1790,94 @@ int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
 }
 EXPORT_SYMBOL(mmc_set_blocklen);
 
+static void mmc_hw_reset_for_init(struct mmc_host *host)
+{
+	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+		return;
+	mmc_host_clk_hold(host);
+	host->ops->hw_reset(host);
+	mmc_host_clk_release(host);
+}
+
+int mmc_can_reset(struct mmc_card *card)
+{
+	u8 rst_n_function;
+
+	if (!mmc_card_mmc(card))
+		return 0;
+	rst_n_function = card->ext_csd.rst_n_function;
+	if ((rst_n_function & EXT_CSD_RST_N_EN_MASK) != EXT_CSD_RST_N_ENABLED)
+		return 0;
+	return 1;
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
+static int mmc_do_hw_reset(struct mmc_host *host, int check)
+{
+	struct mmc_card *card = host->card;
+
+	if (!host->bus_ops->power_restore)
+		return -EOPNOTSUPP;
+
+	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+		return -EOPNOTSUPP;
+
+	if (!card)
+		return -EINVAL;
+
+	if (!mmc_can_reset(card))
+		return -EOPNOTSUPP;
+
+	mmc_host_clk_hold(host);
+	mmc_set_clock(host, host->f_init);
+
+	host->ops->hw_reset(host);
+
+	/* If the reset has happened, then a status command will fail */
+	if (check) {
+		struct mmc_command cmd = {0};
+		int err;
+
+		cmd.opcode = MMC_SEND_STATUS;
+		if (!mmc_host_is_spi(card->host))
+			cmd.arg = card->rca << 16;
+		cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
+		err = mmc_wait_for_cmd(card->host, &cmd, 0);
+		if (!err) {
+			mmc_host_clk_release(host);
+			return -ENOSYS;
+		}
+	}
+
+	host->card->state &= ~(MMC_STATE_HIGHSPEED | MMC_STATE_HIGHSPEED_DDR);
+	if (mmc_host_is_spi(host)) {
+		host->ios.chip_select = MMC_CS_HIGH;
+		host->ios.bus_mode = MMC_BUSMODE_PUSHPULL;
+	} else {
+		host->ios.chip_select = MMC_CS_DONTCARE;
+		host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN;
+	}
+	host->ios.bus_width = MMC_BUS_WIDTH_1;
+	host->ios.timing = MMC_TIMING_LEGACY;
+	mmc_set_ios(host);
+
+	mmc_host_clk_release(host);
+
+	return host->bus_ops->power_restore(host);
+}
+
+int mmc_hw_reset(struct mmc_host *host)
+{
+	return mmc_do_hw_reset(host, 0);
+}
+EXPORT_SYMBOL(mmc_hw_reset);
+
+int mmc_hw_reset_check(struct mmc_host *host)
+{
+	return mmc_do_hw_reset(host, 1);
+}
+EXPORT_SYMBOL(mmc_hw_reset_check);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
 	host->f_init = freq;
@@ -1738,6 +1889,12 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 	mmc_power_up(host);
 
 	/*
+	 * Some eMMCs (with VCCQ always on) may not be reset after power up, so
+	 * do a hardware reset if possible.
+	 */
+	mmc_hw_reset_for_init(host);
+
+	/*
 	 * sdio_reset sends CMD52 to reset card.  Since we do not know
 	 * if the card is being re-initialized, just send it.  CMD52
 	 * should be ignored by SD/eMMC cards.
@@ -1845,6 +2002,7 @@ void mmc_stop_host(struct mmc_host *host)
 
 		mmc_claim_host(host);
 		mmc_detach_bus(host);
+		mmc_power_off(host);
 		mmc_release_host(host);
 		mmc_bus_put(host);
 		return;
@@ -1974,6 +2132,7 @@ int mmc_suspend_host(struct mmc_host *host)
 				host->bus_ops->remove(host);
 			mmc_claim_host(host);
 			mmc_detach_bus(host);
+			mmc_power_off(host);
 			mmc_release_host(host);
 			host->pm_flags = 0;
 			err = 0;
@@ -2061,6 +2220,7 @@ int mmc_pm_notify(struct notifier_block *notify_block,
 			host->bus_ops->remove(host);
 
 		mmc_detach_bus(host);
+		mmc_power_off(host);
 		mmc_release_host(host);
 		host->pm_flags = 0;
 		break;