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

[Johan Rudholm <johan.rudholm@axis.com>]

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 <johanru@axis.com>
---
 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(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 9584bff..492b3e5 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -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;
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index d76597c..f6e0a52 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -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);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 02ad792..7ffa3f2 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -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,
 };
 
 /*
-- 
1.7.2.5