diff options
author | Anton Vorontsov <avorontsov@ru.mvista.com> | 2008-06-17 14:17:39 (GMT) |
---|---|---|
committer | Pierre Ossman <drzeus@drzeus.cx> | 2008-07-15 12:14:41 (GMT) |
commit | 08f80bb5196517a0dfe50dc7c10f234c0ff2f0e8 (patch) | |
tree | aee5e1808521eb3c00ff37d50a2e8957bebbd34b /include/linux/mmc | |
parent | 619ef4b42128709de4d89d209b2c874f560deecd (diff) | |
download | linux-fsl-qoriq-08f80bb5196517a0dfe50dc7c10f234c0ff2f0e8.tar.xz |
mmc: change .get_ro() callback semantics
Now get_ro() callback must return 0/1 values for its logical states, and
negative errno values in case of error. If particular host instance doesn't
support RO/WP switch, it should return -ENOSYS.
This patch changes some hosts in two ways:
1. Now functions should be smart to not return negative values in
"RO asserted" case (particularly gpio_ calls could return negative
values for the outermost GPIOs).
Also, board code usually passes get_ro() callbacks that directly return
gpioreg & bit result, so at91_mci, imxmmc, pxamci and mmc_spi's get_ro()
handlers need take special care when returning platform's values to the
mmc core.
2. In case of host instance didn't implement get_ro() callback, it should
really return -ENOSYS and let the mmc core decide what to do about it
(mmc core thinks the same way as the hosts, so it isn't functional
change).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Diffstat (limited to 'include/linux/mmc')
-rw-r--r-- | include/linux/mmc/host.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 6188e19..753b723 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -58,6 +58,18 @@ struct mmc_host_ops { * * Also note that these functions might sleep, so don't call them * in the atomic contexts! + * + * Return values for the get_ro callback should be: + * 0 for a read/write card + * 1 for a read-only card + * -ENOSYS when not supported (equal to NULL callback) + * or a negative errno value when something bad happened + * + * Return values for the get_ro callback should be: + * 0 for a absent card + * 1 for a present card + * -ENOSYS when not supported (equal to NULL callback) + * or a negative errno value when something bad happened */ void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios); int (*get_ro)(struct mmc_host *host); |