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| author | Jean-Jacques Hiblot <jjhiblot@ti.com> | 2019-07-02 10:53:53 +0200 |
|---|---|---|
| committer | Peng Fan <peng.fan@nxp.com> | 2019-07-15 10:16:49 +0800 |
| commit | cd0b80ec9c97bdd9fb6642671efad8ef3cb33858 (patch) | |
| tree | bc7e8387fdbcb8ecc01046ef8fdcf434e73b449a /include/mmc.h | |
| parent | 863d10044aae5ee40a9cf9a76aed62822cf45c30 (diff) | |
| download | u-boot-cd0b80ec9c97bdd9fb6642671efad8ef3cb33858.zip u-boot-cd0b80ec9c97bdd9fb6642671efad8ef3cb33858.tar.gz u-boot-cd0b80ec9c97bdd9fb6642671efad8ef3cb33858.tar.bz2 | |
mmc: if possible, poll the busy state using DAT0
Using the DAT0 line as a rdy/busy line is an alternative to reading the
status register of the card. It especially useful in situation where the
bus is not in a good shape, like when modes are switched.
This is also how the linux driver behaves.
Note of warning: As per the specification, while polling on DAT0 the CLK
must not turned off: "[...] Without a clock edge the Device (unless
previously disconnected by a deselect command (CMD7)) will force the DAT0
line down, forever. [...]"
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Diffstat (limited to 'include/mmc.h')
| -rw-r--r-- | include/mmc.h | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/include/mmc.h b/include/mmc.h index 7f95c35..cf83b74 100644 --- a/include/mmc.h +++ b/include/mmc.h @@ -445,7 +445,6 @@ struct dm_mmc_ops { int (*execute_tuning)(struct udevice *dev, uint opcode); #endif -#if CONFIG_IS_ENABLED(MMC_UHS_SUPPORT) /** * wait_dat0() - wait until dat0 is in the target state * (CLK must be running during the wait) @@ -456,7 +455,6 @@ struct dm_mmc_ops { * @return 0 if dat0 is in the target state, -ve on error */ int (*wait_dat0)(struct udevice *dev, int state, int timeout); -#endif }; #define mmc_get_ops(dev) ((struct dm_mmc_ops *)(dev)->driver->ops) |