mmc: core: hs200 fixes
This patch fixes following issues when HS200 is enabled:
1. If executing_tuning() host ops is called without mmc_host_clk_hold(),
card clocks might get turned off (if MMC_CLK_GATING is enabled)
while execute_tuning() is in progress. So this patch makes sure
that execute_tuning() is called with mmc_host_clk_hold().
2. If host timing mode is set to HS200 mode, there should not be
any communication with the card until execute_tuning() is completed.
But there is a chance that CMD6 might be sent to enable set HPI_EN
(of HPI_MGMT field in EXT_CSD) before execute_tuning() is called.
So this patch moves this operation after execute_tuning() is completed.
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: girish.shivananjappa@linaro.org
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6defddd..d7d8a93 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1047,22 +1047,6 @@
}
/*
- * Enable HPI feature (if supported)
- */
- if (card->ext_csd.hpi) {
- err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
- EXT_CSD_HPI_MGMT, 1, 0);
- if (err && err != -EBADMSG)
- goto free_card;
- if (err) {
- pr_warning("%s: Enabling HPI failed\n",
- mmc_hostname(card->host));
- err = 0;
- } else
- card->ext_csd.hpi_en = 1;
- }
-
- /*
* Compute bus speed.
*/
max_dtr = (unsigned int)-1;
@@ -1111,9 +1095,12 @@
* 4. execute tuning for HS200
*/
if ((host->caps2 & MMC_CAP2_HS200) &&
- card->host->ops->execute_tuning)
+ card->host->ops->execute_tuning) {
+ mmc_host_clk_hold(card->host);
err = card->host->ops->execute_tuning(card->host,
MMC_SEND_TUNING_BLOCK_HS200);
+ mmc_host_clk_release(card->host);
+ }
if (err) {
pr_warning("%s: tuning execution failed\n",
mmc_hostname(card->host));
@@ -1233,6 +1220,23 @@
}
/*
+ * Enable HPI feature (if supported)
+ */
+ if (card->ext_csd.hpi) {
+ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+ EXT_CSD_HPI_MGMT, 1,
+ card->ext_csd.generic_cmd6_time);
+ if (err && err != -EBADMSG)
+ goto free_card;
+ if (err) {
+ pr_warning("%s: Enabling HPI failed\n",
+ mmc_hostname(card->host));
+ err = 0;
+ } else
+ card->ext_csd.hpi_en = 1;
+ }
+
+ /*
* If cache size is higher than 0, this indicates
* the existence of cache and it can be turned on.
*/