mmc: Add a new callback function to perform the 74 clocks cycle sequence

Add a new callback function *send_init_stream* which start a sequence of
at least 74 clock cycles.
The mmc core uses *mmc_send_init_stream* in order to invoke the callback
function. This will be used during power cycle where the specification
requires such a sequence after power up.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
This commit is contained in:
Jean-Jacques Hiblot 2017-09-21 16:30:01 +02:00 committed by Jaehoon Chung
parent aff5d3c83f
commit 318a7a576b
3 changed files with 29 additions and 0 deletions

View file

@ -51,6 +51,19 @@ int mmc_set_ios(struct mmc *mmc)
return dm_mmc_set_ios(mmc->dev);
}
void dm_mmc_send_init_stream(struct udevice *dev)
{
struct dm_mmc_ops *ops = mmc_get_ops(dev);
if (ops->send_init_stream)
ops->send_init_stream(dev);
}
void mmc_send_init_stream(struct mmc *mmc)
{
dm_mmc_send_init_stream(mmc->dev);
}
int dm_mmc_get_wp(struct udevice *dev)
{
struct dm_mmc_ops *ops = mmc_get_ops(dev);

View file

@ -1198,6 +1198,10 @@ static inline int bus_width(uint cap)
}
#if !CONFIG_IS_ENABLED(DM_MMC)
static void mmc_send_init_stream(struct mmc *mmc)
{
}
static int mmc_set_ios(struct mmc *mmc)
{
int ret = 0;
@ -1983,6 +1987,8 @@ int mmc_start_init(struct mmc *mmc)
mmc_set_bus_width(mmc, 1);
mmc_set_clock(mmc, 1);
mmc_send_init_stream(mmc);
/* Reset the Card */
err = mmc_go_idle(mmc);

View file

@ -360,6 +360,14 @@ struct dm_mmc_ops {
*/
int (*set_ios)(struct udevice *dev);
/**
* send_init_stream() - send the initialization stream: 74 clock cycles
* This is used after power up before sending the first command
*
* @dev: Device to update
*/
void (*send_init_stream)(struct udevice *dev);
/**
* get_cd() - See whether a card is present
*
@ -382,11 +390,13 @@ struct dm_mmc_ops {
int dm_mmc_send_cmd(struct udevice *dev, struct mmc_cmd *cmd,
struct mmc_data *data);
int dm_mmc_set_ios(struct udevice *dev);
void dm_mmc_send_init_stream(struct udevice *dev);
int dm_mmc_get_cd(struct udevice *dev);
int dm_mmc_get_wp(struct udevice *dev);
/* Transition functions for compatibility */
int mmc_set_ios(struct mmc *mmc);
void mmc_send_init_stream(struct mmc *mmc);
int mmc_getcd(struct mmc *mmc);
int mmc_getwp(struct mmc *mmc);