[PATCH 13/13] mmc: sdhci: Change to new way of doing re-tuning

Adrian Hunter
2014-12-05T17:43:49Z

Make use of mmc core support for re-tuning instead
of doing it all in the sdhci driver.

This patch also changes to flag the need for re-tuning
always after runtime suspend when tuning has been used
at initialization. Previously it was only done if
the re-tuning timer was in use.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
drivers/mmc/host/sdhci.c | 113 ++++++----------------------------------------
include/linux/mmc/sdhci.h | 3 --
2 files changed, 14 insertions(+), 102 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index dd4cc4c..4e50db1 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -51,7 +51,6 @@ static void sdhci_finish_data(struct sdhci_host *);

static void sdhci_finish_command(struct sdhci_host *);
static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode);
-static void sdhci_tuning_timer(unsigned long data);
static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);

#ifdef CONFIG_PM_RUNTIME
@@ -249,17 +248,6 @@ static void sdhci_init(struct sdhci_host *host, int soft)
static void sdhci_reinit(struct sdhci_host *host)
{
sdhci_init(host, 0);
- /*
- * Retuning stuffs are affected by different cards inserted and only
- * applicable to UHS-I cards. So reset these fields to their initial
- * value when card is removed.
- */
- if (host->flags & SDHCI_USING_RETUNING_TIMER) {
- host->flags &= ~SDHCI_USING_RETUNING_TIMER;
-
- del_timer_sync(&host->tuning_timer);
- host->flags &= ~SDHCI_NEEDS_RETUNING;
- }
sdhci_enable_card_detection(host);
}

@@ -1345,7 +1333,6 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
struct sdhci_host *host;
int present;
unsigned long flags;
- u32 tuning_opcode;

host = mmc_priv(mmc);

@@ -1393,39 +1380,6 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
host->mrq->cmd->error = -ENOMEDIUM;
tasklet_schedule(&host->finish_tasklet);
} else {
- u32 present_state;
-
- present_state = sdhci_readl(host, SDHCI_PRESENT_STATE);
- /*
- * Check if the re-tuning timer has already expired and there
- * is no on-going data transfer and DAT0 is not busy. If so,
- * we need to execute tuning procedure before sending command.
- */
- if ((host->flags & SDHCI_NEEDS_RETUNING) &&
- !(present_state & (SDHCI_DOING_WRITE | SDHCI_DOING_READ)) &&
- (present_state & SDHCI_DATA_0_LVL_MASK)) {
- if (mmc->card) {
- /* eMMC uses cmd21 but sd and sdio use cmd19 */
- tuning_opcode =
- mmc->card->type == MMC_TYPE_MMC ?
- MMC_SEND_TUNING_BLOCK_HS200 :
- MMC_SEND_TUNING_BLOCK;
-
- /* Here we need to set the host->mrq to NULL,
- * in case the pending finish_tasklet
- * finishes it incorrectly.
- */
- host->mrq = NULL;
-
- spin_unlock_irqrestore(&host->lock, flags);
- sdhci_execute_tuning(mmc, tuning_opcode);
- spin_lock_irqsave(&host->lock, flags);
-
- /* Restore original mmc_request structure */
- host->mrq = mrq;
- }
- }
-
if (mrq->sbc && !(host->flags & SDHCI_AUTO_CMD23))
sdhci_send_command(host, mrq->sbc);
else
@@ -2065,23 +2019,19 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
}

out:
- host->flags &= ~SDHCI_NEEDS_RETUNING;
-
if (tuning_count) {
- host->flags |= SDHCI_USING_RETUNING_TIMER;
- mod_timer(&host->tuning_timer, jiffies + tuning_count * HZ);
+ /*
+ * In case tuning fails, host controllers which support
+ * re-tuning can try tuning again at a later time, when the
+ * re-tuning timer expires. So for these controllers, we
+ * return 0. Since there might be other controllers who do not
+ * have this capability, we return error for them.
+ */
+ err = 0;
}

- /*
- * In case tuning fails, host controllers which support re-tuning can
- * try tuning again at a later time, when the re-tuning timer expires.
- * So for these controllers, we return 0. Since there might be other
- * controllers who do not have this capability, we return error for
- * them. SDHCI_USING_RETUNING_TIMER means the host is currently using
- * a retuning timer to do the retuning for the card.
- */
- if (err && (host->flags & SDHCI_USING_RETUNING_TIMER))
- err = 0;
+ if (!err)
+ mmc_retune_enable(host->mmc, tuning_count);

sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
@@ -2261,20 +2211,6 @@ static void sdhci_timeout_timer(unsigned long data)
spin_unlock_irqrestore(&host->lock, flags);
}

-static void sdhci_tuning_timer(unsigned long data)
-{
- struct sdhci_host *host;
- unsigned long flags;
-
- host = (struct sdhci_host *)data;
-
- spin_lock_irqsave(&host->lock, flags);
-
- host->flags |= SDHCI_NEEDS_RETUNING;
-
- spin_unlock_irqrestore(&host->lock, flags);
-}
-
/*****************************************************************************\
* *
* Interrupt handling *
@@ -2652,11 +2588,8 @@ int sdhci_suspend_host(struct sdhci_host *host)
{
sdhci_disable_card_detection(host);

- /* Disable tuning since we are suspending */
- if (host->flags & SDHCI_USING_RETUNING_TIMER) {
- del_timer_sync(&host->tuning_timer);
- host->flags &= ~SDHCI_NEEDS_RETUNING;
- }
+ mmc_retune_timer_stop(host->mmc);
+ mmc_retune_needed(host->mmc);

if (!device_may_wakeup(mmc_dev(host->mmc))) {
host->ier = 0;
@@ -2706,10 +2639,6 @@ int sdhci_resume_host(struct sdhci_host *host)

sdhci_enable_card_detection(host);

- /* Set the re-tuning expiration flag */
- if (host->flags & SDHCI_USING_RETUNING_TIMER)
- host->flags |= SDHCI_NEEDS_RETUNING;
-
return ret;
}

@@ -2749,11 +2678,8 @@ int sdhci_runtime_suspend_host(struct sdhci_host *host)
{
unsigned long flags;

- /* Disable tuning since we are suspending */
- if (host->flags & SDHCI_USING_RETUNING_TIMER) {
- del_timer_sync(&host->tuning_timer);
- host->flags &= ~SDHCI_NEEDS_RETUNING;
- }
+ mmc_retune_timer_stop(host->mmc);
+ mmc_retune_needed(host->mmc);

spin_lock_irqsave(&host->lock, flags);
host->ier &= SDHCI_INT_CARD_INT;
@@ -2796,10 +2722,6 @@ int sdhci_runtime_resume_host(struct sdhci_host *host)
spin_unlock_irqrestore(&host->lock, flags);
}

- /* Set the re-tuning expiration flag */
- if (host->flags & SDHCI_USING_RETUNING_TIMER)
- host->flags |= SDHCI_NEEDS_RETUNING;
-
spin_lock_irqsave(&host->lock, flags);

host->runtime_suspended = false;
@@ -3333,13 +3255,6 @@ int sdhci_add_host(struct sdhci_host *host)

init_waitqueue_head(&host->buf_ready_int);

- if (host->version >= SDHCI_SPEC_300) {
- /* Initialize re-tuning timer */
- init_timer(&host->tuning_timer);
- host->tuning_timer.data = (unsigned long)host;
- host->tuning_timer.function = sdhci_tuning_timer;
- }
-
sdhci_init(host, 0);

ret = request_threaded_irq(host->irq, sdhci_irq, sdhci_thread_irq,
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index f767a0d..c59ef8d 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -129,13 +129,11 @@ struct sdhci_host {
#define SDHCI_REQ_USE_DMA (1<<2) /* Use DMA for this req. */
#define SDHCI_DEVICE_DEAD (1<<3) /* Device unresponsive */
#define SDHCI_SDR50_NEEDS_TUNING (1<<4) /* SDR50 needs tuning */
-#define SDHCI_NEEDS_RETUNING (1<<5) /* Host needs retuning */
#define SDHCI_AUTO_CMD12 (1<<6) /* Auto CMD12 support */
#define SDHCI_AUTO_CMD23 (1<<7) /* Auto CMD23 support */
#define SDHCI_PV_ENABLED (1<<8) /* Preset value enabled */
#define SDHCI_SDIO_IRQ_ENABLED (1<<9) /* SDIO irq enabled */
#define SDHCI_SDR104_NEEDS_TUNING (1<<10) /* SDR104/HS200 needs tuning */
-#define SDHCI_USING_RETUNING_TIMER (1<<11) /* Host is using a retuning timer for the card */
#define SDHCI_USE_64_BIT_DMA (1<<12) /* Use 64-bit DMA */
#define SDHCI_HS400_TUNING (1<<13) /* Tuning for HS400 */

@@ -201,7 +199,6 @@ struct sdhci_host {
unsigned int tuning_count; /* Timer count for re-tuning */
unsigned int tuning_mode; /* Re-tuning mode supported by host */
#define SDHCI_TUNING_MODE_1 0
- struct timer_list tuning_timer; /* Timer for tuning */

unsigned long private[0] ____cacheline_aligned;
};
--
1.9.1