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

Johan Rudholm
2015-01-12T14:38:19Z

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

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 9959997e..2cdb06e 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -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);

diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index b528c0e..a0bccbc 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -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);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 0b8ec87..d5d576a 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1795,6 +1795,46 @@ static int mmc_power_restore(struct mmc_host *host)
return ret;
}

+int mmc_can_reset(struct mmc_card *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 0;
+ return 1;
+}
+EXPORT_SYMBOL(mmc_can_reset);
+
+static int mmc_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;
+
+ if (!mmc_can_reset(card))
+ 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);
+ mmc_host_clk_release(host);
+
+ return mmc_power_restore(host);
+}
+
static const struct mmc_bus_ops mmc_ops = {
.remove = mmc_remove,
.detect = mmc_detect,
@@ -1805,6 +1845,7 @@ static const struct mmc_bus_ops mmc_ops = {
.power_restore = mmc_power_restore,
.alive = mmc_alive,
.shutdown = mmc_shutdown,
+ .reset = mmc_reset,
};

/*
--
1.7.2.5