korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-15 16:24:13 +08:00
Code Issues Packages Projects Releases Wiki Activity

sdhci: let the controller wait for busy state to end

Browse Source 
The sdhci controllers can interrupt us when the busy state from the
card has ended, saving CPU cycles and power.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This commit is contained in:
Pierre Ossman 2008-07-25 01:09:08 +02:00
parent 3fa8749e58
commit e809517f6f
1 changed files with 33 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
drivers/mmc/host/sdhci.c
View File

@ -1266,9 +1266,31 @@ static void sdhci_cmd_irq(struct sdhci_host *host, u32 intmask)
SDHCI_INT_INDEX))
host->cmd->error = -EILSEQ;
if (host->cmd->error)
if (host->cmd->error) {
tasklet_schedule(&host->finish_tasklet);
else if (intmask & SDHCI_INT_RESPONSE)
return;
}
/*
* The host can send and interrupt when the busy state has
* ended, allowing us to wait without wasting CPU cycles.
* Unfortunately this is overloaded on the "data complete"
* interrupt, so we need to take some care when handling
* it.
*
* Note: The 1.0 specification is a bit ambiguous about this
* feature so there might be some problems with older
* controllers.
*/
if (host->cmd->flags & MMC_RSP_BUSY) {
if (host->cmd->data)
DBG("Cannot wait for busy signal when also "
"doing a data transfer");
else
return;
}
if (intmask & SDHCI_INT_RESPONSE)
sdhci_finish_command(host);
}
@ -1278,11 +1300,16 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
if (!host->data) {
/*
* A data end interrupt is sent together with the response
* for the stop command.
* The "data complete" interrupt is also used to
* indicate that a busy state has ended. See comment
* above in sdhci_cmd_irq().
*/
if (intmask & SDHCI_INT_DATA_END)
return;
if (host->cmd && (host->cmd->flags & MMC_RSP_BUSY)) {
if (intmask & SDHCI_INT_DATA_END) {
sdhci_finish_command(host);
return;
}
}
printk(KERN_ERR "%s: Got data interrupt 0x%08x even "
"though no data operation was in progress.\n",