mmc: dw_mmc: guarantee stop-abort cmd in data errors

In error cases, DTO interrupt may or may not be generated depending
on remained data. Stop/Abort command ensures DTO generation for that
situation. Currently if 'stop' field of data is empty, there is no
stop/abort command. So, it could hang waiting DTO. This change
reinforces these cases.

Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 64 insertions, 20 deletions

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 649127e71894..b4328ad59cf0 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -29,6 +29,7 @@
 #include <linux/irq.h>
 #include <linux/mmc/host.h>
 #include <linux/mmc/mmc.h>
+#include <linux/mmc/sdio.h>
 #include <linux/mmc/dw_mmc.h>
 #include <linux/bitops.h>
 #include <linux/regulator/consumer.h>
@@ -246,10 +247,15 @@ static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd)
 
         cmdr = cmd->opcode;
 
-        if (cmdr == MMC_STOP_TRANSMISSION)
+        if (cmd->opcode == MMC_STOP_TRANSMISSION ||
+            cmd->opcode == MMC_GO_IDLE_STATE ||
+            cmd->opcode == MMC_GO_INACTIVE_STATE ||
+            (cmd->opcode == SD_IO_RW_DIRECT &&
+             ((cmd->arg >> 9) & 0x1FFFF) == SDIO_CCCR_ABORT))
                 cmdr |= SDMMC_CMD_STOP;
         else
-                cmdr |= SDMMC_CMD_PRV_DAT_WAIT;
+                if (cmd->opcode != MMC_SEND_STATUS && cmd->data)
+                        cmdr |= SDMMC_CMD_PRV_DAT_WAIT;
 
         if (cmd->flags & MMC_RSP_PRESENT) {
                 /* We expect a response, so set this bit */
@@ -276,6 +282,40 @@ static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd)
         return cmdr;
 }
 
+static u32 dw_mci_prep_stop_abort(struct dw_mci *host, struct mmc_command *cmd)
+{
+        struct mmc_command *stop;
+        u32 cmdr;
+
+        if (!cmd->data)
+                return 0;
+
+        stop = &host->stop_abort;
+        cmdr = cmd->opcode;
+        memset(stop, 0, sizeof(struct mmc_command));
+
+        if (cmdr == MMC_READ_SINGLE_BLOCK ||
+            cmdr == MMC_READ_MULTIPLE_BLOCK ||
+            cmdr == MMC_WRITE_BLOCK ||
+            cmdr == MMC_WRITE_MULTIPLE_BLOCK) {
+                stop->opcode = MMC_STOP_TRANSMISSION;
+                stop->arg = 0;
+                stop->flags = MMC_RSP_R1B | MMC_CMD_AC;
+        } else if (cmdr == SD_IO_RW_EXTENDED) {
+                stop->opcode = SD_IO_RW_DIRECT;
+                stop->arg |= (1 << 31) | (0 << 28) | (SDIO_CCCR_ABORT << 9) |
+                             ((cmd->arg >> 28) & 0x7);
+                stop->flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_AC;
+        } else {
+                return 0;
+        }
+
+        cmdr = stop->opcode | SDMMC_CMD_STOP |
+                SDMMC_CMD_RESP_CRC | SDMMC_CMD_RESP_EXP;
+
+        return cmdr;
+}
+
 static void dw_mci_start_command(struct dw_mci *host,
                                  struct mmc_command *cmd, u32 cmd_flags)
 {
@@ -290,9 +330,10 @@ static void dw_mci_start_command(struct dw_mci *host,
         mci_writel(host, CMD, cmd_flags | SDMMC_CMD_START);
 }
 
-static void send_stop_cmd(struct dw_mci *host, struct mmc_data *data)
+static inline void send_stop_abort(struct dw_mci *host, struct mmc_data *data)
 {
-        dw_mci_start_command(host, data->stop, host->stop_cmdr);
+        struct mmc_command *stop = data->stop ? data->stop : &host->stop_abort;
+        dw_mci_start_command(host, stop, host->stop_cmdr);
 }
 
 /* DMA interface functions */
@@ -828,6 +869,8 @@ static void __dw_mci_start_request(struct dw_mci *host,
 
         if (mrq->stop)
                 host->stop_cmdr = dw_mci_prepare_command(slot->mmc, mrq->stop);
+        else
+                host->stop_cmdr = dw_mci_prep_stop_abort(host, cmd);
 }
 
 static void dw_mci_start_request(struct dw_mci *host,
@@ -1190,13 +1233,9 @@ static void dw_mci_tasklet_func(unsigned long priv)
 
                         if (cmd->data && cmd->error) {
                                 dw_mci_stop_dma(host);
-                                if (data->stop) {
-                                        send_stop_cmd(host, data);
-                                        state = STATE_SENDING_STOP;
-                                        break;
-                                } else {
-                                        host->data = NULL;
-                                }
+                                send_stop_abort(host, data);
+                                state = STATE_SENDING_STOP;
+                                break;
                         }
 
                         if (!host->mrq->data || cmd->error) {
@@ -1211,8 +1250,7 @@ static void dw_mci_tasklet_func(unsigned long priv)
                         if (test_and_clear_bit(EVENT_DATA_ERROR,
                                                &host->pending_events)) {
                                 dw_mci_stop_dma(host);
-                                if (data->stop)
-                                        send_stop_cmd(host, data);
+                                send_stop_abort(host, data);
                                 state = STATE_DATA_ERROR;
                                 break;
                         }
@@ -1272,7 +1310,7 @@ static void dw_mci_tasklet_func(unsigned long priv)
                                 data->error = 0;
                         }
 
-                        if (!data->stop) {
+                        if (!data->stop && !data->error) {
                                 dw_mci_request_end(host, host->mrq);
                                 goto unlock;
                         }
@@ -1284,8 +1322,10 @@ static void dw_mci_tasklet_func(unsigned long priv)
                         }
 
                         prev_state = state = STATE_SENDING_STOP;
-                        if (!data->error)
-                                send_stop_cmd(host, data);
+                        if (data->stop && !data->error) {
+                                /* stop command for open-ended transfer*/
+                                send_stop_abort(host, data);
+                        }
                         /* fall through */
 
                 case STATE_SENDING_STOP:
@@ -1304,7 +1344,12 @@ static void dw_mci_tasklet_func(unsigned long priv)
 
                         host->cmd = NULL;
                         host->data = NULL;
-                        dw_mci_command_complete(host, host->mrq->stop);
+
+                        if (host->mrq->stop)
+                                dw_mci_command_complete(host, host->mrq->stop);
+                        else
+                                host->cmd_status = 0;
+
                         dw_mci_request_end(host, host->mrq);
                         goto unlock;
 
@@ -1888,11 +1933,10 @@ static void dw_mci_work_routine_card(struct work_struct *work)
                                         case STATE_DATA_ERROR:
                                                 if (mrq->data->error == -EINPROGRESS)
                                                         mrq->data->error = -ENOMEDIUM;
-                                                if (!mrq->stop)
-                                                        break;
                                                 /* fall through */
                                         case STATE_SENDING_STOP:
-                                                mrq->stop->error = -ENOMEDIUM;
+                                                if (mrq->stop)
+                                                        mrq->stop->error = -ENOMEDIUM;
                                                 break;
                                         }