From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
To verify a signal voltage switch at initialization of UHS cards the
.card_busy callback is used. For some of the ST-variants, card busy
detection on the DAT0 pin is supported.
We extend the variant struct with a busy_detect flag to indicate
support for it. A corresponding busy detect function, which polls the
busy status bit, is then set to the .card_busy callback.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
drivers/mmc/host/mmci.c | 33 ++++++++++++++++++++++++++++++++-
drivers/mmc/host/mmci.h | 2 ++
2 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 4530217..fa1a7d7 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -61,6 +61,7 @@ static unsigned int fmax = 515633;
* @pwrreg_powerup: power up value for MMCIPOWER register
* @signal_direction: input/out direction of bus signals can be indicated
* @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock
+ * @busy_detect: true if busy detection on dat0 is supported
*/
struct variant_data {
unsigned int clkreg;
@@ -74,6 +75,7 @@ struct variant_data {
u32 pwrreg_powerup;
bool signal_direction;
bool pwrreg_clkgate;
+ bool busy_detect;
};
static struct variant_data variant_arm = {
@@ -132,6 +134,7 @@ static struct variant_data variant_ux500 = {
.pwrreg_powerup = MCI_PWR_ON,
.signal_direction = true,
.pwrreg_clkgate = true,
+ .busy_detect = true,
};
static struct variant_data variant_ux500v2 = {
@@ -146,8 +149,28 @@ static struct variant_data variant_ux500v2 = {
.pwrreg_powerup = MCI_PWR_ON,
.signal_direction = true,
.pwrreg_clkgate = true,
+ .busy_detect = true,
};
+static int mmci_card_busy(struct mmc_host *mmc)
+{
+ struct mmci_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ int busy = 0;
+
+ pm_runtime_get_sync(mmc_dev(mmc));
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (readl(host->base + MMCISTATUS) & MCI_ST_CARDBUSY)
+ busy = 1;
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ pm_runtime_mark_last_busy(mmc_dev(mmc));
+ pm_runtime_put_autosuspend(mmc_dev(mmc));
+
+ return busy;
+}
+
/*
* Validate mmc prerequisites
*/
@@ -193,6 +216,9 @@ static void mmci_write_pwrreg(struct mmci_host *host, u32 pwr)
*/
static void mmci_write_datactrlreg(struct mmci_host *host, u32 datactrl)
{
+ /* Keep ST Micro busy mode if enabled */
+ datactrl |= host->datactrl_reg & MCI_ST_DPSM_BUSYMODE;
+
if (host->datactrl_reg != datactrl) {
host->datactrl_reg = datactrl;
writel(datactrl, host->base + MMCIDATACTRL);
@@ -1306,7 +1332,7 @@ static irqreturn_t mmci_cd_irq(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static const struct mmc_host_ops mmci_ops = {
+static struct mmc_host_ops mmci_ops = {
.request = mmci_request,
.pre_req = mmci_pre_request,
.post_req = mmci_post_request,
@@ -1443,6 +1469,11 @@ static int mmci_probe(struct amba_device *dev,
goto clk_disable;
}
+ if (variant->busy_detect) {
+ mmci_ops.card_busy = mmci_card_busy;
+ mmci_write_datactrlreg(host, MCI_ST_DPSM_BUSYMODE);
+ }
+
mmc->ops = &mmci_ops;
/*
* The ARM and ST versions of the block have slightly different
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 0b6cc54..69080fa 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -94,6 +94,7 @@
/* Extended status bits for the ST Micro variants */
#define MCI_ST_SDIOIT (1 << 22)
#define MCI_ST_CEATAEND (1 << 23)
+#define MCI_ST_CARDBUSY (1 << 24)
#define MMCICLEAR 0x038
#define MCI_CMDCRCFAILCLR (1 << 0)
@@ -110,6 +111,7 @@
/* Extended status bits for the ST Micro variants */
#define MCI_ST_SDIOITC (1 << 22)
#define MCI_ST_CEATAENDC (1 << 23)
+#define MCI_ST_BUSYENDC (1 << 24)
#define MMCIMASK0 0x03c
#define MCI_CMDCRCFAILMASK (1 << 0)
--
1.7.10
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