From: Bin Shi <bin....@csr.com>
some controllers share data bus or other pins between
multi-controllers and need to switch the functions of shared pins
runtime.
this patch requested those shared pins before actual hardware access
and release them after access
Signed-off-by: Bin Shi <bin....@csr.com>
Cc: Binghua Duan <binghua.d...@csr.com>
Cc: Andrei Warkentin <andr...@motorola.com>
Cc: Philip Rakity <prak...@marvell.com>
Signed-off-by: Barry Song <21cn...@gmail.com>
---
drivers/mmc/host/sdhci.c | 13 +++++++++++++
drivers/mmc/host/sdhci.h | 2 ++
2 files changed, 15 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index f70e21e..92ae9f7 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1143,6 +1143,13 @@ static void sdhci_request(struct mmc_host *mmc,
struct mmc_request *mrq)
host = mmc_priv(mmc);
+ /*
+ * some controllers share data bus or other pins between
multi-controller
+ * and need to switch the function of pins runtime
+ */
+ if (host->ops->get_shared_pins)
+ host->ops->get_shared_pins(host);
+
spin_lock_irqsave(&host->lock, flags);
WARN_ON(host->mrq != NULL);
@@ -1417,6 +1424,12 @@ static void sdhci_tasklet_finish(unsigned long param)
spin_unlock_irqrestore(&host->lock, flags);
mmc_request_done(host->mmc, mrq);
+
+ /*
+ * release shared pins so that other controllers can use them
+ */
+ if (host->ops->put_shared_pins)
+ host->ops->put_shared_pins(host);
}
static void sdhci_timeout_timer(unsigned long data)
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index c6e25a7..5a26cfe 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -231,6 +231,8 @@ struct sdhci_ops {
unsigned int (*get_ro)(struct sdhci_host *host);
void (*platform_reset_enter)(struct sdhci_host *host, u8 mask);
void (*platform_reset_exit)(struct sdhci_host *host, u8 mask);
+ unsigned int (*get_shared_pins)(struct sdhci_host *host);
+ unsigned int (*put_shared_pins)(struct sdhci_host *host);
};
#ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
--
1.7.1
--
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