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mtd: dataflash: replace msleep with usleep_range 

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@brickedbrain.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
This commit is contained in:
Luca Ellero 2018-04-18 11:26:26 +02:00 committed by Boris Brezillon
parent 0e210b542c
commit c3c9a2c4b9
1 changed files with 1 additions and 1 deletions
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2
drivers/mtd/devices/mtd_dataflash.c
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@ -140,7 +140,7 @@ static int dataflash_waitready(struct spi_device *spi)
if (status & (1 << 7)) /* RDY/nBSY */ if (status & (1 << 7)) /* RDY/nBSY */
return status; return status;
msleep(3); usleep_range(3000, 4000);
} }
} }