[PATCH] mtd: dataflash: replace msleep with usleep_range
Luca Ellero
luca.ellero at brickedbrain.com
Wed Apr 18 02:26:26 PDT 2018
Since msleep is based on jiffies, this 3 ms sleep becomes actually 20 ms.
Worst of all, since this sleep is used in a loop when writing, a single page
write (256 to 1024 bytes) causes 17 ms extra time.
When writing large files (for example u-boot is usually 512 KB) this delay
adds up to minutes.
See Documentation/timers/timers-howto.txt "Why not msleep for (1ms - 20ms)".
Signed-off-by: Luca Ellero <luca.ellero at brickedbrain.com>
---
drivers/mtd/devices/mtd_dataflash.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c
index aaaeaae..3a6f450 100644
--- a/drivers/mtd/devices/mtd_dataflash.c
+++ b/drivers/mtd/devices/mtd_dataflash.c
@@ -140,7 +140,7 @@ static int dataflash_waitready(struct spi_device *spi)
if (status & (1 << 7)) /* RDY/nBSY */
return status;
- msleep(3);
+ usleep_range(3000, 4000);
}
}
--
2.7.4
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