From: Bin Shi <bin.shi@xxxxxxx>
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.shi@xxxxxxx>
Cc: Binghua Duan <binghua.duan@xxxxxxx>
Signed-off-by: Barry Song <21cnbao@xxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 13 +++++++++++++
drivers/mmc/host/sdhci.h | 2 ++
include/linux/mmc/sdhci.h | 2 ++
3 files changed, 17 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index f31077d..7b07152 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1379,6 +1379,13 @@ static void sdhci_tasklet_finish(unsigned long param)
sdhci_reset(host, SDHCI_RESET_DATA);
}
+ /*
+ * some controllers share data bus or other pins between multi-controller
+ * and need to switch the function of pins runtime
+ */
+ if (host->quirks & SDHCI_QUIRK_SHARED_PINS)
+ host->ops->get_shared_pins(host);
+
host->mrq = NULL;
host->cmd = NULL;
host->data = NULL;
@@ -1391,6 +1398,12 @@ 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->quirks & SDHCI_QUIRK_SHARED_PINS)
+ host->ops->get_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 85750a9..9d918a5 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -229,6 +229,8 @@ struct sdhci_ops {
void (*platform_send_init_74_clocks)(struct sdhci_host *host,
u8 power_mode);
unsigned int (*get_ro)(struct sdhci_host *host);
+ unsigned int (*get_shared_pins)(struct sdhci_host *host);
+ unsigned int (*put_shared_pins)(struct sdhci_host *host);
};
#ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 83bd9f7..32ab422 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -85,6 +85,8 @@ struct sdhci_host {
#define SDHCI_QUIRK_NO_HISPD_BIT (1<<29)
/* Controller treats ADMA descriptors with length 0000h incorrectly */
#define SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC (1<<30)
+/* Controller shared data bus or other pins with other controllers */
+#define SDHCI_QUIRK_SHARED_PINS (1<<31)
int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.7.1
--
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