linux/drivers/mmc
Aaro Koskinen 194b888af8 mmc: omap: fix the maximum timeout setting
[ Upstream commit a6327b5e57 ]

When running OMAP1 kernel on QEMU, MMC access is annoyingly noisy:

	MMC: CTO of 0xff and 0xfe cannot be used!
	MMC: CTO of 0xff and 0xfe cannot be used!
	MMC: CTO of 0xff and 0xfe cannot be used!
	[ad inf.]

Emulator warnings appear to be valid. The TI document SPRU680 [1]
("OMAP5910 Dual-Core Processor MultiMedia Card/Secure Data Memory Card
(MMC/SD) Reference Guide") page 36 states that the maximum timeout is 253
cycles and "0xff and 0xfe cannot be used".

Fix by using 0xfd as the maximum timeout.

Tested using QEMU 2.5 (Siemens SX1 machine, OMAP310), and also checked on
real hardware using Palm TE (OMAP310), Nokia 770 (OMAP1710) and Nokia N810
(OMAP2420) that MMC works as before.

[1] http://www.ti.com/lit/ug/spru680/spru680.pdf

Fixes: 730c9b7e66 ("[MMC] Add OMAP MMC host driver")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:33:02 +02:00
..
core mmc:fix a bug when max_discard is 0 2019-03-23 20:09:57 +01:00
host mmc: omap: fix the maximum timeout setting 2019-04-05 22:33:02 +02:00
Kconfig mmc: core: Remove option not to use blk-mq 2017-12-11 12:55:02 +01:00
Makefile mmc: Kconfig: downgrade CONFIG_MMC_DEBUG for host drivers only 2017-08-30 14:01:34 +02:00