omap_hsmmc: Fix response type for busy after response
authorAdrian Hunter <adrian.hunter@nokia.com>
Mon, 12 Jan 2009 14:13:08 +0000 (16:13 +0200)
committerPierre Ossman <drzeus@drzeus.cx>
Tue, 24 Mar 2009 20:30:04 +0000 (21:30 +0100)
Some MMC commands result in the card becoming busy after
the response is received.  This needs to be specified
for the omap_hsmmc host controller, which is what this
patch does.  However, the effect is that some commands
with no data will cause a Transfer Complete (TC) interrupt
in addition to the Command Complete (CC) interrupt.
In order to deal with that, the irq handler has needed
a few changes also.

The benefit of this change is that the omap_hsmmc host
controller driver now waits for the TC interrupt while
the card is busy, so the mmc_block driver needs to poll
the card status just once instead of repeatedly.
i.e. the net result is more sleep and less cpu.

The command sequence for open-ended multi-block write
with DMA is now:

Issue write command CMD25
Receive CC interrupt
Data is sent
Receive TC interrupt (DMA is done)
Issue stop command CMD12
Receive CC interrupt
Card is busy
Receive TC interrupt
Card is now ready for next transfer

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
drivers/mmc/host/omap_hsmmc.c

index 5ff2ca2..1f84bd4 100644 (file)
@@ -150,6 +150,7 @@ struct mmc_omap_host {
        int                     initstr;
        int                     slot_id;
        int                     dbclk_enabled;
+       int                     response_busy;
        struct  omap_mmc_platform_data  *pdata;
 };
 
@@ -244,10 +245,14 @@ mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd,
        OMAP_HSMMC_WRITE(host->base, ISE, INT_EN_MASK);
        OMAP_HSMMC_WRITE(host->base, IE, INT_EN_MASK);
 
+       host->response_busy = 0;
        if (cmd->flags & MMC_RSP_PRESENT) {
                if (cmd->flags & MMC_RSP_136)
                        resptype = 1;
-               else
+               else if (cmd->flags & MMC_RSP_BUSY) {
+                       resptype = 3;
+                       host->response_busy = 1;
+               } else
                        resptype = 2;
        }
 
@@ -282,6 +287,15 @@ mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd,
 static void
 mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
 {
+       if (!data) {
+               struct mmc_request *mrq = host->mrq;
+
+               host->mrq = NULL;
+               mmc_omap_fclk_lazy_disable(host);
+               mmc_request_done(host->mmc, mrq);
+               return;
+       }
+
        host->data = NULL;
 
        if (host->use_dma && host->dma_ch != -1)
@@ -323,7 +337,7 @@ mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
                        cmd->resp[0] = OMAP_HSMMC_READ(host->base, RSP10);
                }
        }
-       if (host->data == NULL || cmd->error) {
+       if ((host->data == NULL && !host->response_busy) || cmd->error) {
                host->mrq = NULL;
                mmc_request_done(host->mmc, cmd->mrq);
        }
@@ -413,7 +427,7 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
        struct mmc_data *data;
        int end_cmd = 0, end_trans = 0, status;
 
-       if (host->cmd == NULL && host->data == NULL) {
+       if (host->mrq == NULL) {
                OMAP_HSMMC_WRITE(host->base, STAT,
                        OMAP_HSMMC_READ(host->base, STAT));
                return IRQ_HANDLED;
@@ -438,18 +452,24 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
                                }
                                end_cmd = 1;
                        }
-                       if (host->data) {
-                               mmc_dma_cleanup(host, -ETIMEDOUT);
+                       if (host->data || host->response_busy) {
+                               if (host->data)
+                                       mmc_dma_cleanup(host, -ETIMEDOUT);
+                               host->response_busy = 0;
                                mmc_omap_reset_controller_fsm(host, SRD);
                        }
                }
                if ((status & DATA_TIMEOUT) ||
                        (status & DATA_CRC)) {
-                       if (host->data) {
-                               if (status & DATA_TIMEOUT)
-                                       mmc_dma_cleanup(host, -ETIMEDOUT);
+                       if (host->data || host->response_busy) {
+                               int err = (status & DATA_TIMEOUT) ?
+                                               -ETIMEDOUT : -EILSEQ;
+
+                               if (host->data)
+                                       mmc_dma_cleanup(host, err);
                                else
-                                       mmc_dma_cleanup(host, -EILSEQ);
+                                       host->mrq->cmd->error = err;
+                               host->response_busy = 0;
                                mmc_omap_reset_controller_fsm(host, SRD);
                                end_trans = 1;
                        }