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omap_hsmmc: Fix response type for busy after response 

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>
This commit is contained in:
Adrian Hunter 2009-01-12 16:13:08 +02:00 committed by Pierre Ossman
parent 82788ff532
commit 4a694dc915
1 changed files with 29 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
drivers/mmc/host/omap_hsmmc.c
View 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;
}