mmc: core: hw_reset changes

PATCH Applied Johan Rudholm 2 participants 7 messages Jan 12, 2015 – Jan 13, 2015 MMC, SD and SDIO

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Johan Rudholm

author

2015-01-12 14:38 UTC #0 lore raw

v7 cover mmc: core: hw_reset changes

Make the mmc_hw_reset routine more generic, by putting the (e)MMC- specific stuff in the new bus_ops->reset in mmc.c. Add a bus_ops->reset for SD cards, allowing them to be restarted when errors occur.

For MMC cards, always check if the reset was sucessful. This allows us to remove the mmc_hw_reset_check() interface.

As I don't have an eMMC device myself, much less one with a reset line, I'd be very happy if someone could help me test the code with an eMMC?

v7:
- Rename bus_ops->hw_reset to reset
- Move the send_status check to mmc.c
- Put the changes concerning mmc_hw_reset_check in a separate patch

v6:
- Always perform the mmc_send_status reset check, which allows us to have only one interface to the card reset functions
- Because of this, add the bus_ops->hw_reset to sd.c instead of falling back to a power_cycle

v5:
- Move the mmc_test-specific code to mmc_test.c
- Fall back to a power_cycle if the bus_ops->hw_reset is missing
- Because of this, skip the bus_ops->hw_reset in sd.c

v4:
- Rebase onto next

v3:
- Keep mmc_can_reset
- Always set bus_mode = MMC_BUSMODE_PUSHPULL in mmc_set_initial_state()

v2:
- Call the new bus_ops member hw_reset instead of power_reset
- Create mmc_set_initial_state and call it from mmc_mmc_hw_reset instead of mmc_power_up
- Keep "mmc_hw_reset" naming

Johan Rudholm (3):
mmc: core: always check status after reset
mmc: core: refactor the hw_reset routines
mmc: sd: add reset bus_ops callback

 drivers/mmc/card/mmc_test.c |   18 +++++--------
 drivers/mmc/core/core.c     |   59 +++++++-----------------------------------
 drivers/mmc/core/core.h     |    1 +
 drivers/mmc/core/mmc.c      |   41 +++++++++++++++++++++++++++++
 drivers/mmc/core/sd.c       |    7 +++++
 include/linux/mmc/core.h    |    1 -
 6 files changed, 66 insertions(+), 61 deletions(-)

Signature · 1 line

1.7.2.5

Johan Rudholm

author

2015-01-12 14:38 UTC #1 lore raw

PATCH v7 1/3 mmc: core: always check status after reset

Always check if the card is alive after a successful reset. This allows us to remove mmc_hw_reset_check(), leaving mmc_hw_reset() as the only card reset interface.

Signed-off-by Johan Rudholm <[email protected]>

---
 drivers/mmc/card/mmc_test.c |   18 +++++++-----------
 drivers/mmc/core/core.c     |   24 +++++-------------------
 include/linux/mmc/core.h    |    1 -
 3 files changed, 12 insertions(+), 31 deletions(-)

drivers/mmc/card/mmc_test.c +7 ~~-11~~

index 0a7430f..7dac469 100644
@@ -2342,20 +2342,16 @@ static int mmc_test_hw_reset(struct mmc_test_card *test)
 	struct mmc_host *host = card->host;
 	int err;
 
-	err = mmc_hw_reset_check(host);
+	if (!mmc_card_mmc(card) || !mmc_can_reset(card))
+		return RESULT_UNSUP_CARD;
+
+	err = mmc_hw_reset(host);
 	if (!err)
 		return RESULT_OK;
+	else if (err == -EOPNOTSUPP)
+		return RESULT_UNSUP_HOST;
 
-	if (err == -ENOSYS)
-		return RESULT_FAIL;
-
-	if (err != -EOPNOTSUPP)
-		return err;
-
-	if (!mmc_can_reset(card))
-		return RESULT_UNSUP_CARD;
-
-	return RESULT_UNSUP_HOST;
+	return RESULT_FAIL;
 }
 
 static const struct mmc_test_case mmc_test_cases[] = {

drivers/mmc/core/core.c +5 ~~-19~~

index d3bfbdf..9959997e 100644
@@ -2286,9 +2286,10 @@ int mmc_can_reset(struct mmc_card *card)
 }
 EXPORT_SYMBOL(mmc_can_reset);
 
-static int mmc_do_hw_reset(struct mmc_host *host, int check)
+static int mmc_hw_reset(struct mmc_host *host)
 {
 	struct mmc_card *card = host->card;
+	u32 status;
 
 	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
 		return -EOPNOTSUPP;

@@ -2305,13 +2306,9 @@ static int mmc_do_hw_reset(struct mmc_host *host, int check)
 	host->ops->hw_reset(host);
 
 	/* If the reset has happened, then a status command will fail */
-	if (check) {
-		u32 status;
-
-		if (!mmc_send_status(card, &status)) {
-			mmc_host_clk_release(host);
-			return -ENOSYS;
-		}
+	if (!mmc_send_status(card, &status)) {
+		mmc_host_clk_release(host);
+		return -ENOSYS;
 	}
 
 	/* Set initial state and call mmc_set_ios */

@@ -2321,19 +2318,8 @@ static int mmc_do_hw_reset(struct mmc_host *host, int check)
 
 	return host->bus_ops->power_restore(host);
 }
-
-int mmc_hw_reset(struct mmc_host *host)
-{
-	return mmc_do_hw_reset(host, 0);
-}
 EXPORT_SYMBOL(mmc_hw_reset);
 
-int mmc_hw_reset_check(struct mmc_host *host)
-{
-	return mmc_do_hw_reset(host, 1);
-}
-EXPORT_SYMBOL(mmc_hw_reset_check);
-
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
 	host->f_init = freq;

include/linux/mmc/core.h +0 -1

index cb2b040..160448f 100644
@@ -182,7 +182,6 @@ extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen);
 extern int mmc_set_blockcount(struct mmc_card *card, unsigned int blockcount,
 			      bool is_rel_write);
 extern int mmc_hw_reset(struct mmc_host *host);
-extern int mmc_hw_reset_check(struct mmc_host *host);
 extern int mmc_can_reset(struct mmc_card *card);
 
 extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);

Signature · 1 line

1.7.2.5

Johan Rudholm

author

2015-01-12 14:38 UTC #2 lore raw

PATCH v7 2/3 mmc: core: refactor the hw_reset routines

In reply to Johan Rudholm

Move the (e)MMC specific hw_reset code from core.c into mmc.c. Call the code from the new bus_ops member "reset". This also allows for adding a SD card specific reset procedure.

Signed-off-by Johan Rudholm <[email protected]>

---
 drivers/mmc/core/core.c |   45 ++++++++++-----------------------------------
 drivers/mmc/core/core.h |    1 +
 drivers/mmc/core/mmc.c  |   41 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 52 insertions(+), 35 deletions(-)

drivers/mmc/core/core.c +10 ~~-35~~

index 9959997e..2cdb06e 100644
@@ -2273,50 +2273,25 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
 	mmc_host_clk_release(host);
 }
 
-int mmc_can_reset(struct mmc_card *card)
+int mmc_hw_reset(struct mmc_host *host)
 {
-	u8 rst_n_function;
-
-	if (!mmc_card_mmc(card))
-		return 0;
-	rst_n_function = card->ext_csd.rst_n_function;
-	if ((rst_n_function & EXT_CSD_RST_N_EN_MASK) != EXT_CSD_RST_N_ENABLED)
-		return 0;
-	return 1;
-}
-EXPORT_SYMBOL(mmc_can_reset);
-
-static int mmc_hw_reset(struct mmc_host *host)
-{
-	struct mmc_card *card = host->card;
-	u32 status;
-
-	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-		return -EOPNOTSUPP;
+	int ret;
 
-	if (!card)
+	if (!host->card)
 		return -EINVAL;
 
-	if (!mmc_can_reset(card))
+	mmc_bus_get(host);
+	if (!host->bus_ops || host->bus_dead || !host->bus_ops->reset) {
+		mmc_bus_put(host);
 		return -EOPNOTSUPP;
-
-	mmc_host_clk_hold(host);
-	mmc_set_clock(host, host->f_init);
-
-	host->ops->hw_reset(host);
-
-	/* If the reset has happened, then a status command will fail */
-	if (!mmc_send_status(card, &status)) {
-		mmc_host_clk_release(host);
-		return -ENOSYS;
 	}
 
-	/* Set initial state and call mmc_set_ios */
-	mmc_set_initial_state(host);
+	ret = host->bus_ops->reset(host);
+	mmc_bus_put(host);
 
-	mmc_host_clk_release(host);
+	pr_warn("%s: tried to reset card\n", mmc_hostname(host));
 
-	return host->bus_ops->power_restore(host);
+	return ret;
 }
 EXPORT_SYMBOL(mmc_hw_reset);

drivers/mmc/core/core.h +1 -0

index b528c0e..a0bccbc 100644
@@ -27,6 +27,7 @@ struct mmc_bus_ops {
 	int (*power_restore)(struct mmc_host *);
 	int (*alive)(struct mmc_host *);
 	int (*shutdown)(struct mmc_host *);
+	int (*reset)(struct mmc_host *);
 };
 
 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);

drivers/mmc/core/mmc.c +41 -0

53 lines not on this page · raw message

Signature · 1 line

1.7.2.5

Johan Rudholm

author

2015-01-12 14:38 UTC #3 lore raw

PATCH v7 3/3 mmc: sd: add reset bus_ops callback

In reply to Johan Rudholm

Enable power cycle and re-initialization of SD cards via the reset bus_ops. Power cycling a buggy SD card sometimes helps it get back on track.

Signed-off-by Johan Rudholm <[email protected]>

---
 drivers/mmc/core/sd.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

drivers/mmc/core/sd.c +7 -0

index 29fccdc..36d5333 100644
@@ -1197,6 +1197,12 @@ static int mmc_sd_power_restore(struct mmc_host *host)
 	return ret;
 }
 
+static int mmc_sd_reset(struct mmc_host *host)
+{
+	mmc_power_cycle(host, host->card->ocr);
+	return mmc_sd_power_restore(host);
+}
+
 static const struct mmc_bus_ops mmc_sd_ops = {
 	.remove = mmc_sd_remove,
 	.detect = mmc_sd_detect,

@@ -1207,6 +1213,7 @@ static const struct mmc_bus_ops mmc_sd_ops = {
 	.power_restore = mmc_sd_power_restore,
 	.alive = mmc_sd_alive,
 	.shutdown = mmc_sd_suspend,
+	.reset = mmc_sd_reset,
 };
 
 /*

Signature · 1 line

1.7.2.5

Ulf Hansson

Applied

2015-01-12 15:11 UTC #4 lore raw

In reply to Johan Rudholm

Quoted 53 lines · Johan Rudholm

Make the mmc_hw_reset routine more generic, by putting the (e)MMC- specific stuff in the new bus_ops->reset in mmc.c. Add a bus_ops->reset for SD cards, allowing them to be restarted when errors occur.
For MMC cards, always check if the reset was sucessful. This allows us to remove the mmc_hw_reset_check() interface.
As I don't have an eMMC device myself, much less one with a reset line, I'd be very happy if someone could help me test the code with an eMMC?
v7:
- Rename bus_ops->hw_reset to reset
- Move the send_status check to mmc.c
- Put the changes concerning mmc_hw_reset_check in a separate patch
v6:
- Always perform the mmc_send_status reset check, which allows us to have only one interface to the card reset functions
- Because of this, add the bus_ops->hw_reset to sd.c instead of falling back to a power_cycle
v5:
- Move the mmc_test-specific code to mmc_test.c
- Fall back to a power_cycle if the bus_ops->hw_reset is missing
- Because of this, skip the bus_ops->hw_reset in sd.c
v4:
- Rebase onto next
v3:
- Keep mmc_can_reset
- Always set bus_mode = MMC_BUSMODE_PUSHPULL in mmc_set_initial_state()
v2:
- Call the new bus_ops member hw_reset instead of power_reset
- Create mmc_set_initial_state and call it from mmc_mmc_hw_reset instead of mmc_power_up
- Keep "mmc_hw_reset" naming
Johan Rudholm (3):
mmc: core: always check status after reset
mmc: core: refactor the hw_reset routines
mmc: sd: add reset bus_ops callback
 drivers/mmc/card/mmc_test.c |   18 +++++--------
 drivers/mmc/core/core.c     |   59 +++++++-----------------------------------
 drivers/mmc/core/core.h     |    1 +
 drivers/mmc/core/mmc.c      |   41 +++++++++++++++++++++++++++++
 drivers/mmc/core/sd.c       |    7 +++++
 include/linux/mmc/core.h    |    1 -
 6 files changed, 66 insertions(+), 61 deletions(-)

Quoted 3 lines

--
1.7.2.5

Thanks! Applied for next.

Kind regards
Uffe

Ulf Hansson

2015-01-13 08:19 UTC #5 lore raw

Quoted 54 lines · Ulf Hansson

Quoted 53 lines · Johan Rudholm
Make the mmc_hw_reset routine more generic, by putting the (e)MMC- specific stuff in the new bus_ops->reset in mmc.c. Add a bus_ops->reset for SD cards, allowing them to be restarted when errors occur.
For MMC cards, always check if the reset was sucessful. This allows us to remove the mmc_hw_reset_check() interface.
As I don't have an eMMC device myself, much less one with a reset line, I'd be very happy if someone could help me test the code with an eMMC?
v7:
- Rename bus_ops->hw_reset to reset
- Move the send_status check to mmc.c
- Put the changes concerning mmc_hw_reset_check in a separate patch
v6:
- Always perform the mmc_send_status reset check, which allows us to have only one interface to the card reset functions
- Because of this, add the bus_ops->hw_reset to sd.c instead of falling back to a power_cycle
v5:
- Move the mmc_test-specific code to mmc_test.c
- Fall back to a power_cycle if the bus_ops->hw_reset is missing
- Because of this, skip the bus_ops->hw_reset in sd.c
v4:
- Rebase onto next
v3:
- Keep mmc_can_reset
- Always set bus_mode = MMC_BUSMODE_PUSHPULL in mmc_set_initial_state()
v2:
- Call the new bus_ops member hw_reset instead of power_reset
- Create mmc_set_initial_state and call it from mmc_mmc_hw_reset instead of mmc_power_up
- Keep "mmc_hw_reset" naming
Johan Rudholm (3):
mmc: core: always check status after reset
mmc: core: refactor the hw_reset routines
mmc: sd: add reset bus_ops callback
 drivers/mmc/card/mmc_test.c |   18 +++++--------
 drivers/mmc/core/core.c     |   59 +++++++-----------------------------------
 drivers/mmc/core/core.h     |    1 +
 drivers/mmc/core/mmc.c      |   41 +++++++++++++++++++++++++++++
 drivers/mmc/core/sd.c       |    7 +++++
 include/linux/mmc/core.h    |    1 -
 6 files changed, 66 insertions(+), 61 deletions(-)

Quoted 5 lines

Quoted 3 lines
--
1.7.2.5
Thanks! Applied for next.

Patch 1 caused compiler error and thus breaking bisectability. I decided to fix it up myself this time, but future wise please make sure each patch builds separately.

Kind regards
Uffe

Johan Rudholm

author

2015-01-13 08:26 UTC #6 lore raw

2015-01-13 9:19 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 59 lines · Ulf Hansson

Quoted 58 lines · Johan Rudholm
Quoted 56 lines
Make the mmc_hw_reset routine more generic, by putting the (e)MMC- specific stuff in the new bus_ops->reset in mmc.c. Add a bus_ops->reset for SD cards, allowing them to be restarted when errors occur.
For MMC cards, always check if the reset was sucessful. This allows us to remove the mmc_hw_reset_check() interface.
As I don't have an eMMC device myself, much less one with a reset line, I'd be very happy if someone could help me test the code with an eMMC?
v7:
- Rename bus_ops->hw_reset to reset
- Move the send_status check to mmc.c
- Put the changes concerning mmc_hw_reset_check in a separate patch
v6:
- Always perform the mmc_send_status reset check, which allows us to have only one interface to the card reset functions
- Because of this, add the bus_ops->hw_reset to sd.c instead of falling back to a power_cycle
v5:
- Move the mmc_test-specific code to mmc_test.c
- Fall back to a power_cycle if the bus_ops->hw_reset is missing
- Because of this, skip the bus_ops->hw_reset in sd.c
v4:
- Rebase onto next
v3:
- Keep mmc_can_reset
- Always set bus_mode = MMC_BUSMODE_PUSHPULL in mmc_set_initial_state()
v2:
- Call the new bus_ops member hw_reset instead of power_reset
- Create mmc_set_initial_state and call it from mmc_mmc_hw_reset instead of mmc_power_up
- Keep "mmc_hw_reset" naming
Johan Rudholm (3):
mmc: core: always check status after reset
mmc: core: refactor the hw_reset routines
mmc: sd: add reset bus_ops callback
 drivers/mmc/card/mmc_test.c |   18 +++++--------
 drivers/mmc/core/core.c     |   59 +++++++-----------------------------------
 drivers/mmc/core/core.h     |    1 +
 drivers/mmc/core/mmc.c      |   41 +++++++++++++++++++++++++++++
 drivers/mmc/core/sd.c       |    7 +++++
 include/linux/mmc/core.h    |    1 -
 6 files changed, 66 insertions(+), 61 deletions(-)
--
1.7.2.5

Quoted 5 lines

Quoted 1 line
Thanks! Applied for next.
Patch 1 caused compiler error and thus breaking bisectability. I decided to fix it up myself this time, but future wise please make sure each patch builds separately.

Very sorry about that, won't happen again. Thanks!

//Johan