Commit 9d7c6eee authored by Jarkko Lavinen's avatar Jarkko Lavinen Committed by Pierre Ossman

MMC: OMAP: Do not busy wait for end of command for ever

The limit was a fixed 100k limit in the busy loop, which is not
accurate. It would better to have time limit for the worst case
which occurs when sending 80 cycles at 400 kHz and takes about
200 microseconds, so limit the max time spend in the busy loop
for some 250 microseconds.
Signed-off-by: default avatarJarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent 0f602ec7
...@@ -1276,11 +1276,17 @@ static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) ...@@ -1276,11 +1276,17 @@ static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
OMAP_MMC_WRITE(host, CON, dsor); OMAP_MMC_WRITE(host, CON, dsor);
slot->saved_con = dsor; slot->saved_con = dsor;
if (ios->power_mode == MMC_POWER_ON) { if (ios->power_mode == MMC_POWER_ON) {
/* worst case at 400kHz, 80 cycles makes 200 microsecs */
int usecs = 250;
/* Send clock cycles, poll completion */ /* Send clock cycles, poll completion */
OMAP_MMC_WRITE(host, IE, 0); OMAP_MMC_WRITE(host, IE, 0);
OMAP_MMC_WRITE(host, STAT, 0xffff); OMAP_MMC_WRITE(host, STAT, 0xffff);
OMAP_MMC_WRITE(host, CMD, 1 << 7); OMAP_MMC_WRITE(host, CMD, 1 << 7);
while ((OMAP_MMC_READ(host, STAT) & 1) == 0); while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
udelay(1);
usecs--;
}
OMAP_MMC_WRITE(host, STAT, 1); OMAP_MMC_WRITE(host, STAT, 1);
} }
......
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