mmc: dw_mmc: Support predefined mutiple block transfers

This patch adds the support for predefined multiple block r/w.
dw_mmc can support MMC_CAP_CMD23 capability.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/dw_mmc.c

@@ -588,11 +588,11 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 	mci_writel(host, CTYPE, (slot->ctype << slot->id));
 }
 
-static void dw_mci_start_request(struct dw_mci *host,
-				 struct dw_mci_slot *slot)
+static void __dw_mci_start_request(struct dw_mci *host,
+				   struct dw_mci_slot *slot,
+				   struct mmc_command *cmd)
 {
 	struct mmc_request *mrq;
-	struct mmc_command *cmd;
 	struct mmc_data	*data;
 	u32 cmdflags;
 
@@ -610,14 +610,13 @@ static void dw_mci_start_request(struct dw_mci *host,
 	host->completed_events = 0;
 	host->data_status = 0;
 
-	data = mrq->data;
+	data = cmd->data;
 	if (data) {
 		dw_mci_set_timeout(host);
 		mci_writel(host, BYTCNT, data->blksz*data->blocks);
 		mci_writel(host, BLKSIZ, data->blksz);
 	}
 
-	cmd = mrq->cmd;
 	cmdflags = dw_mci_prepare_command(slot->mmc, cmd);
 
 	/* this is the first command, send the initialization clock */
@@ -635,6 +634,16 @@ static void dw_mci_start_request(struct dw_mci *host,
 		host->stop_cmdr = dw_mci_prepare_command(slot->mmc, mrq->stop);
 }
 
+static void dw_mci_start_request(struct dw_mci *host,
+				 struct dw_mci_slot *slot)
+{
+	struct mmc_request *mrq = slot->mrq;
+	struct mmc_command *cmd;
+
+	cmd = mrq->sbc ? mrq->sbc : mrq->cmd;
+	__dw_mci_start_request(host, slot, cmd);
+}
+
 /* must be called with host->lock held */
 static void dw_mci_queue_request(struct dw_mci *host, struct dw_mci_slot *slot,
 				 struct mmc_request *mrq)
@@ -889,7 +898,14 @@ static void dw_mci_tasklet_func(unsigned long priv)
 			cmd = host->cmd;
 			host->cmd = NULL;
 			set_bit(EVENT_CMD_COMPLETE, &host->completed_events);
-			dw_mci_command_complete(host, host->mrq->cmd);
+			dw_mci_command_complete(host, cmd);
+			if (cmd == host->mrq->sbc && !cmd->error) {
+				prev_state = state = STATE_SENDING_CMD;
+				__dw_mci_start_request(host, host->cur_slot,
+						       host->mrq->cmd);
+				goto unlock;
+			}
+
 			if (!host->mrq->data || cmd->error) {
 				dw_mci_request_end(host, host->mrq);
 				goto unlock;
@@ -967,6 +983,12 @@ static void dw_mci_tasklet_func(unsigned long priv)
 				goto unlock;
 			}
 
+			if (host->mrq->sbc && !data->error) {
+				data->stop->error = 0;
+				dw_mci_request_end(host, host->mrq);
+				goto unlock;
+			}
+
 			prev_state = state = STATE_SENDING_STOP;
 			if (!data->error)
 				send_stop_cmd(host, data);