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mmc: core: hw_reset changes

PATCH Superseded Johan Rudholm 2 participants 9 messages Nov 24, 2014 – Jan 9, 2015 MMC, SD and SDIO

v4 of 7 Superseded Latest is v7 →

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Johan Rudholm

author
#0 lore raw

v4 cover mmc: core: hw_reset changes

Make the mmc_hw_reset routines more generic, so we can easily add a power cycle of SD cards as well. Also simplify the (e)MMC specific parts of the reset code.

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?

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 (2):
mmc: core: turn hw_reset into a bus_ops
mmc: sd: add hw_reset callback

 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 drivers/mmc/core/sd.c   |   13 +++++++++++
 4 files changed, 76 insertions(+), 38 deletions(-)
Signature · 1 line
1.7.2.5
author
#1 lore raw

PATCH v4 1/2 mmc: core: turn hw_reset into a bus_ops

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +18 -38
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
 	mmc_host_clk_release(host);
 }
 
-int mmc_can_reset(struct mmc_card *card)
-{
-	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);
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-	struct mmc_card *card = host->card;
-
-	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))
+	if (!host->bus_ops || !host->bus_ops->hw_reset ||
+			host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
 		return -EOPNOTSUPP;
 
-	mmc_host_clk_hold(host);
-	mmc_set_clock(host, host->f_init);
+	ret = host->bus_ops->hw_reset(host, 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;
-		}
-	}
-
-	/* Set initial state and call mmc_set_ios */
-	mmc_set_initial_state(host);
+	if (check == MMC_HW_RESET_TEST_CARD)
+		return ret;
 
-	mmc_host_clk_release(host);
+	pr_warn("%s: tried to reset card (status %d)\n",
+						mmc_hostname(host), ret);
 
 	return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-	return mmc_do_hw_reset(host, 0);
+	return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-	return mmc_do_hw_reset(host, 1);
+	return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+	return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
 	host->f_init = freq;
drivers/mmc/core/core.h +5 -0
index d76597c..f6e0a52 100644
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
 	int (*power_restore)(struct mmc_host *);
 	int (*alive)(struct mmc_host *);
 	int (*shutdown)(struct mmc_host *);
+	int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET	0
+#define MMC_HW_RESET_TEST	1
+#define MMC_HW_RESET_CHECK	2
+#define MMC_HW_RESET_TEST_CARD	3
 };
 
 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);
drivers/mmc/core/mmc.c +40 -0
index 02ad792..7ffa3f2 100644
@@ -1821,6 +1821,45 @@ static int mmc_power_restore(struct mmc_host *host)
 	return ret;
 }
 
+static int mmc_mmc_hw_reset(struct mmc_host *host, int test)
+{
+	struct mmc_card *card = host->card;
+	u8 rst_n_function;
+
+	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 -EOPNOTSUPP;
+
+	if (test == MMC_HW_RESET_TEST_CARD)
+		return 0;
+
+	if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+		return -EOPNOTSUPP;
+
+	if (test == MMC_HW_RESET_TEST)
+		return 0;
+
+	mmc_host_clk_hold(host);
+	mmc_set_clock(host, host->f_init);
+
+	host->ops->hw_reset(host);
+
+	if (test == MMC_HW_RESET_CHECK) {
+		u32 status;
+
+		if (!mmc_send_status(card, &status)) {
+			mmc_host_clk_release(host);
+			return -ENOSYS;
+		}
+	}
+
+	mmc_set_initial_state(host);
+
+	mmc_host_clk_release(host);
+
+	return 0;
+}
+
 static const struct mmc_bus_ops mmc_ops = {
 	.remove = mmc_remove,
 	.detect = mmc_detect,

@@ -1831,6 +1870,7 @@ static const struct mmc_bus_ops mmc_ops = {
 	.power_restore = mmc_power_restore,
 	.alive = mmc_alive,
 	.shutdown = mmc_shutdown,
+	.hw_reset = mmc_mmc_hw_reset,
 };
 
 /*
Signature · 1 line
1.7.2.5
#2 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

Quoted 21 lines · Johan Rudholm

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -2
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
 
-int mmc_can_reset(struct mmc_card *card)
-{

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 10 lines
drivers/mmc/core/core.c +0 -10
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Quoted 5 lines
drivers/mmc/core/core.c +1 -2
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 10 lines
drivers/mmc/core/core.c +2 -5
-
-       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))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

In fact, I would prefer to have none of them.

Quoted 62 lines
drivers/mmc/core/core.h +0 -0
 };
 
 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);
drivers/mmc/core/mmc.c +40 -1
index 02ad792..7ffa3f2 100644
@@ -1821,6 +1821,45 @@ static int mmc_power_restore(struct mmc_host *host)
        return ret;
 }
 
+static int mmc_mmc_hw_reset(struct mmc_host *host, int test)
+{
+       struct mmc_card *card = host->card;
+       u8 rst_n_function;
+
+       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 -EOPNOTSUPP;
+
+       if (test == MMC_HW_RESET_TEST_CARD)
+               return 0;
+
+       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
+               return -EOPNOTSUPP;
+
+       if (test == MMC_HW_RESET_TEST)
+               return 0;
+
+       mmc_host_clk_hold(host);
+       mmc_set_clock(host, host->f_init);
+
+       host->ops->hw_reset(host);
+
+       if (test == MMC_HW_RESET_CHECK) {
+               u32 status;
+
+               if (!mmc_send_status(card, &status)) {
+                       mmc_host_clk_release(host);
+                       return -ENOSYS;
+               }
+       }
+
+       mmc_set_initial_state(host);
+
+       mmc_host_clk_release(host);
+
+       return 0;
+}
+
 static const struct mmc_bus_ops mmc_ops = {
        .remove = mmc_remove,
        .detect = mmc_detect,

@@ -1831,6 +1870,7 @@ static const struct mmc_bus_ops mmc_ops = {
        .power_restore = mmc_power_restore,
        .alive = mmc_alive,
        .shutdown = mmc_shutdown,
+       .hw_reset = mmc_mmc_hw_reset,
 };
 
 /*
--
Quoted 2 lines

1.7.2.5

Kind regards
Uffe

author
#3 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

Hi Ulf,

2014-11-25 14:48 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 20 lines · Johan Rudholm
Quoted 19 lines

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -0
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
Quoted 14 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 12 lines
drivers/mmc/core/core.c +0 -12
-int mmc_can_reset(struct mmc_card *card)
-{
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Yes. Maybe we should move this stuff to mmc_test instead. We could also move the code that checks if the reset worked or not to mmc_test, since this is the only place where the check is performed.

Quoted 14 lines
Quoted 14 lines
drivers/mmc/core/core.c +3 -6
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;
-
-       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-               return -EOPNOTSUPP;
+       int ret;
 
-       if (!card)
+       if (!host->card)
                return -EINVAL;
Quoted 8 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 1 line
drivers/mmc/core/core.c +0 -1
-       if (!mmc_can_reset(card))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

Got it, thanks.

Quoted 74 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

Quoted 1 line

In fact, I would prefer to have none of them.

If we move the test and check functionality to mmc_test, I think we can avoid these. What do you think of this approach?

//Johan

#4 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

Quoted 141 lines · Johan Rudholm

Hi Ulf,

2014-11-25 14:48 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 20 lines · Johan Rudholm
Quoted 19 lines

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -0
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
Quoted 14 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 12 lines
drivers/mmc/core/core.c +0 -12
-int mmc_can_reset(struct mmc_card *card)
-{
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Yes. Maybe we should move this stuff to mmc_test instead. We could also move the code that checks if the reset worked or not to mmc_test, since this is the only place where the check is performed.

Quoted 14 lines
Quoted 14 lines
drivers/mmc/core/core.c +3 -6
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;
-
-       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-               return -EOPNOTSUPP;
+       int ret;
 
-       if (!card)
+       if (!host->card)
                return -EINVAL;
Quoted 8 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 1 line
drivers/mmc/core/core.c +0 -1
-       if (!mmc_can_reset(card))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

Got it, thanks.

Quoted 74 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

Quoted 4 lines
Quoted 1 line

In fact, I would prefer to have none of them.

If we move the test and check functionality to mmc_test, I think we can avoid these. What do you think of this approach?

I like that approach.

In principle I think we should have only one API for hardware reset, typically that should be mmc_hw_reset(). Then, convert mmc_test_hw_reset() into invoking the mmc_hw_reset() API and let it handle further tests by itself.

Kind regards
Uffe

author
#5 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

2014-11-27 10:50 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 147 lines · Johan Rudholm
Quoted 141 lines

Hi Ulf,

2014-11-25 14:48 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 20 lines · Johan Rudholm
Quoted 19 lines

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -0
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
Quoted 14 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 12 lines
drivers/mmc/core/core.c +0 -12
-int mmc_can_reset(struct mmc_card *card)
-{
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Yes. Maybe we should move this stuff to mmc_test instead. We could also move the code that checks if the reset worked or not to mmc_test, since this is the only place where the check is performed.

Quoted 14 lines
Quoted 14 lines
drivers/mmc/core/core.c +3 -6
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;
-
-       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-               return -EOPNOTSUPP;
+       int ret;
 
-       if (!card)
+       if (!host->card)
                return -EINVAL;
Quoted 8 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 1 line
drivers/mmc/core/core.c +0 -1
-       if (!mmc_can_reset(card))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

Got it, thanks.

Quoted 74 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

Quoted 4 lines
Quoted 1 line

In fact, I would prefer to have none of them.

If we move the test and check functionality to mmc_test, I think we can avoid these. What do you think of this approach?

Quoted 6 lines

I like that approach.

In principle I think we should have only one API for hardware reset, typically that should be mmc_hw_reset(). Then, convert mmc_test_hw_reset() into invoking the mmc_hw_reset() API and let it handle further tests by itself.

The trouble is that mmc_test_hw_reset() needs to check if the reset was a success after calling host_ops->hw_reset, but before calling mmc_set_initial_values and bus_ops->power_restore, so some provisions for this need to be done in mmc_hw_reset. I'll soon send up a new patchset, please let me know if I'm on the right track.

BR, Johan

#6 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

Quoted 150 lines · Johan Rudholm

2014-11-27 10:50 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 149 lines · Johan Rudholm
Quoted 141 lines

Hi Ulf,

2014-11-25 14:48 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 20 lines · Johan Rudholm
Quoted 19 lines

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -0
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
Quoted 14 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 12 lines
drivers/mmc/core/core.c +0 -12
-int mmc_can_reset(struct mmc_card *card)
-{
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Yes. Maybe we should move this stuff to mmc_test instead. We could also move the code that checks if the reset worked or not to mmc_test, since this is the only place where the check is performed.

Quoted 14 lines
Quoted 14 lines
drivers/mmc/core/core.c +3 -6
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;
-
-       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-               return -EOPNOTSUPP;
+       int ret;
 
-       if (!card)
+       if (!host->card)
                return -EINVAL;
Quoted 8 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 1 line
drivers/mmc/core/core.c +0 -1
-       if (!mmc_can_reset(card))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

Got it, thanks.

Quoted 74 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

Quoted 4 lines
Quoted 1 line

In fact, I would prefer to have none of them.

If we move the test and check functionality to mmc_test, I think we can avoid these. What do you think of this approach?

I like that approach.

Quoted 7 lines
Quoted 4 lines

In principle I think we should have only one API for hardware reset, typically that should be mmc_hw_reset(). Then, convert mmc_test_hw_reset() into invoking the mmc_hw_reset() API and let it handle further tests by itself.

The trouble is that mmc_test_hw_reset() needs to check if the reset was a success after calling host_ops->hw_reset, but before calling

How about always do the CMD13 check when host_ops->hw_reset() exist and returns suceess? The error handling for CMD13 check could be print an error. It shouldn't prevent us from proceeding with the rest of power cycle operations.

Quoted 4 lines

mmc_set_initial_values and bus_ops->power_restore, so some provisions for this need to be done in mmc_hw_reset. I'll soon send up a new patchset, please let me know if I'm on the right track.

Kind regards
Uffe

author
#7 lore raw

Re: [PATCH v4 1/2] mmc: core: turn hw_reset into a bus_ops

Hi Ulf,

2014-12-01 11:50 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 156 lines · Johan Rudholm
Quoted 155 lines

2014-11-27 10:50 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 153 lines · Johan Rudholm
Quoted 141 lines

Hi Ulf,

2014-11-25 14:48 GMT+01:00 Ulf Hansson <[email protected]>:

Quoted 20 lines · Johan Rudholm
Quoted 19 lines

Move the (e)MMC specific hw_reset code from core.c into mmc.c and call it from the new bus_ops member hw_reset. This also lets us add code for resetting SD cards as well.

Signed-off-by Johan Rudholm <[email protected]>
---
 drivers/mmc/core/core.c |   56 +++++++++++++++-------------------------------
 drivers/mmc/core/core.h |    5 ++++
 drivers/mmc/core/mmc.c  |   40 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 38 deletions(-)
drivers/mmc/core/core.c +0 -0
index 9584bff..492b3e5 100644
@@ -2245,67 +2245,47 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
        mmc_host_clk_release(host);
 }
Quoted 14 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2259

Quoted 12 lines
drivers/mmc/core/core.c +0 -12
-int mmc_can_reset(struct mmc_card *card)
-{
-       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);

Isn't the mmc_can_reset() function used from mmc_test.c?

Yes. Maybe we should move this stuff to mmc_test instead. We could also move the code that checks if the reset worked or not to mmc_test, since this is the only place where the check is performed.

Quoted 14 lines
Quoted 14 lines
drivers/mmc/core/core.c +3 -6
-
+/* Reset card in a bus-specific way */
 static int mmc_do_hw_reset(struct mmc_host *host, int check)
 {
-       struct mmc_card *card = host->card;
-
-       if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
-               return -EOPNOTSUPP;
+       int ret;
 
-       if (!card)
+       if (!host->card)
                return -EINVAL;
Quoted 8 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2271

Quoted 1 line
drivers/mmc/core/core.c +0 -1
-       if (!mmc_can_reset(card))

You need a mmc_bus_get() here before accessing the host->bus_ops callbacks.

Well, if you would executed this code with the host claimed and from the mmc block layer, you can be sure the bus_ops to exist. Now, since this is an exported function, I think you need to be more safe to also do the mmc_bus_get|put().

Got it, thanks.

Quoted 74 lines

drivers/mmc/core/core.c static void mmc_hw_reset_for_init(struct mmc_host *host) · line 2260

Quoted 7 lines
drivers/mmc/core/core.c +3 -2
+       if (!host->bus_ops || !host->bus_ops->hw_reset ||
+                       host->bus_ops->hw_reset(host, MMC_HW_RESET_TEST))
                return -EOPNOTSUPP;
 
-       mmc_host_clk_hold(host);
-       mmc_set_clock(host, host->f_init);
+       ret = host->bus_ops->hw_reset(host, check);

What's going on here? You are invoking the ->hw_reset() callback twice. That seems odd.

Quoted 53 lines
drivers/mmc/core/core.c +12 -17
-       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;
-               }
-       }
-
-       /* Set initial state and call mmc_set_ios */
-       mmc_set_initial_state(host);
+       if (check == MMC_HW_RESET_TEST_CARD)
+               return ret;
 
-       mmc_host_clk_release(host);
+       pr_warn("%s: tried to reset card (status %d)\n",
+                                               mmc_hostname(host), ret);
 
        return host->bus_ops->power_restore(host);
 }
 
 int mmc_hw_reset(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 0);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_RESET);
 }
 EXPORT_SYMBOL(mmc_hw_reset);
 
 int mmc_hw_reset_check(struct mmc_host *host)
 {
-       return mmc_do_hw_reset(host, 1);
+       return mmc_do_hw_reset(host, MMC_HW_RESET_CHECK);
 }
 EXPORT_SYMBOL(mmc_hw_reset_check);
 
+int mmc_can_reset(struct mmc_card *card)
+{
+       return mmc_do_hw_reset(card->host, MMC_HW_RESET_TEST_CARD);
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
 static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 {
        host->f_init = freq;
drivers/mmc/core/core.h +0 -0
index d76597c..f6e0a52 100644

drivers/mmc/core/core.h struct mmc_bus_ops { · line 34

Quoted 8 lines
drivers/mmc/core/core.h +5 -0
@@ -27,6 +27,11 @@ struct mmc_bus_ops {
        int (*power_restore)(struct mmc_host *);
        int (*alive)(struct mmc_host *);
        int (*shutdown)(struct mmc_host *);
+       int (*hw_reset)(struct mmc_host *, int);
+#define MMC_HW_RESET_RESET     0
+#define MMC_HW_RESET_TEST      1
+#define MMC_HW_RESET_CHECK     2
+#define MMC_HW_RESET_TEST_CARD 3

Urgh. Is there a way to remove all this? I just don't like all these options.

Quoted 4 lines
Quoted 1 line

In fact, I would prefer to have none of them.

If we move the test and check functionality to mmc_test, I think we can avoid these. What do you think of this approach?

I like that approach.

In principle I think we should have only one API for hardware reset, typically that should be mmc_hw_reset(). Then, convert mmc_test_hw_reset() into invoking the mmc_hw_reset() API and let it handle further tests by itself.

Quoted 7 lines
Quoted 2 lines

The trouble is that mmc_test_hw_reset() needs to check if the reset was a success after calling host_ops->hw_reset, but before calling

How about always do the CMD13 check when host_ops->hw_reset() exist and returns suceess? The error handling for CMD13 check could be print an error. It shouldn't prevent us from proceeding with the rest of power cycle operations.

Sorry for having dropped this conversation for so long. I've thought about the best approach for a while now and I'll soon send out a patch set with your suggestions incorporated.

Kind regards, Johan

author
#8 lore raw

PATCH v4 2/2 mmc: sd: add hw_reset callback

In reply to Johan Rudholm

Enable power cycle and re-initialization of SD cards via the hw_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 |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)
drivers/mmc/core/sd.c +13 -0
index d90a6de..a7fa124 100644
@@ -1180,6 +1180,18 @@ static int mmc_sd_runtime_resume(struct mmc_host *host)
 	return 0;
 }
 
+static int mmc_sd_hw_reset(struct mmc_host *host, int test)
+{
+	struct mmc_card *card = host->card;
+
+	if (test == MMC_HW_RESET_TEST || test == MMC_HW_RESET_TEST_CARD)
+		return 0;
+
+	mmc_power_cycle(host, card->ocr);
+
+	return 0;
+}
+
 static int mmc_sd_power_restore(struct mmc_host *host)
 {
 	int ret;

@@ -1201,6 +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,
+	.hw_reset = mmc_sd_hw_reset,
 };
 
 /*
Signature · 1 line
1.7.2.5