Hi Stephen,
On Tue, Jun 4, 2013 at 4:36 PM, Stephen Warren swarren@wwwdotorg.org wrote:
That seems like a reasonable way for the code to work. However, you'd need to modify common/env_mmc.c:init_mmc_for_env() so that it saves off mmc->part_num before switching MMC partitions, so that fini_mmc_for_env() knows which partition to switch back to. Right now, it relies on the fact that mmc_switch_part() does not update mmc->part_num, and hence uses that value to save the previously selected partition ID.
Also, if you make this change, I think you can update common/cmd_mmc.c:do_mmcops(), since it will no longer need to update mmc->part_num after a successful switch.
I understood your second suggestion and did the changes below, but I am not sure on the first one regarding the change you proposed inside init_mmc_for_env().
Here is what I did so far:
diff --git a/common/cmd_mmc.c b/common/cmd_mmc.c index 7d82469..20a2792 100644 --- a/common/cmd_mmc.c +++ b/common/cmd_mmc.c @@ -243,8 +243,6 @@ static int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
if (part != mmc->part_num) { ret = mmc_switch_part(dev, part); - if (!ret) - mmc->part_num = part;
printf("switch to partions #%d, %s\n", part, (!ret) ? "OK" : "ERROR"); diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 0a2f535..e8d2ea6 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -702,14 +702,20 @@ static int mmc_change_freq(struct mmc *mmc)
int mmc_switch_part(int dev_num, unsigned int part_num) { + int ret; struct mmc *mmc = find_mmc_device(dev_num);
if (!mmc) return -1;
- return mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_PART_CONF, + ret = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_PART_CONF, (mmc->part_config & ~PART_ACCESS_MASK) | (part_num & PART_ACCESS_MASK)); + + if (!ret) + mmc->part_num = part_num; + + return ret; }
int mmc_getcd(struct mmc *mmc)