diff mbox

[Quantal,1/2] mfd: rtsx: Optimize card detect flow

Message ID 1362558903-9403-1-git-send-email-adam.lee@canonical.com
State New
Headers show

Commit Message

Adam Lee March 6, 2013, 8:35 a.m. UTC 
BugLink: http://launchpad.net/bugs/1148892

1. Schedule card detect work at the end of the ISR
2. Callback function ops->cd_deglitch may delay for a period of time.
It is not proper to call this callback when local irq disabled.
3. Card detect flow can't be executed in parallel with other card reader
operations, so it's better to be protected by mutex.

Signed-off-by: Wei WANG <wei_wang@realsil.com.cn>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
(cherry-picked from commit 504decc0a063e6a09a1e5b203ca68bc21dfffde9 upstream)
Signed-off-by: Adam Lee <adam.lee@canonical.com>
---
 drivers/mfd/rtsx_pcr.c |   31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

Comments

Stefan Bader March 6, 2013, 10:58 a.m. UTC | #1 
Both seem cherry picks, the justification in the bug report is a bit sparse (or
formally not existing). Both went in with 3.9, so I would wonder whether those
should not be made requests/proposals for upstream stable inclusion. Though I'd
leave the decision to the stable team.

-Stefan
Tim Gardner March 6, 2013, 1:39 p.m. UTC | #2
diff mbox

Patch

diff --git a/drivers/mfd/rtsx_pcr.c b/drivers/mfd/rtsx_pcr.c
index 8048d4c..f67f015 100644
--- a/drivers/mfd/rtsx_pcr.c
+++ b/drivers/mfd/rtsx_pcr.c
@@ -748,7 +748,7 @@  static void rtsx_pci_card_detect(struct work_struct *work)
 	struct delayed_work *dwork;
 	struct rtsx_pcr *pcr;
 	unsigned long flags;
-	unsigned int card_detect = 0;
+	unsigned int card_detect = 0, card_inserted, card_removed;
 	u32 irq_status;
 
 	dwork = to_delayed_work(work);
@@ -756,25 +756,32 @@  static void rtsx_pci_card_detect(struct work_struct *work)
 
 	dev_dbg(&(pcr->pci->dev), "--> %s\n", __func__);
 
+	mutex_lock(&pcr->pcr_mutex);
 	spin_lock_irqsave(&pcr->lock, flags);
 
 	irq_status = rtsx_pci_readl(pcr, RTSX_BIPR);
 	dev_dbg(&(pcr->pci->dev), "irq_status: 0x%08x\n", irq_status);
 
-	if (pcr->card_inserted || pcr->card_removed) {
+	irq_status &= CARD_EXIST;
+	card_inserted = pcr->card_inserted & irq_status;
+	card_removed = pcr->card_removed;
+	pcr->card_inserted = 0;
+	pcr->card_removed = 0;
+
+	spin_unlock_irqrestore(&pcr->lock, flags);
+
+	if (card_inserted || card_removed) {
 		dev_dbg(&(pcr->pci->dev),
 				"card_inserted: 0x%x, card_removed: 0x%x\n",
-				pcr->card_inserted, pcr->card_removed);
+				card_inserted, card_removed);
 
 		if (pcr->ops->cd_deglitch)
-			pcr->card_inserted = pcr->ops->cd_deglitch(pcr);
+			card_inserted = pcr->ops->cd_deglitch(pcr);
 
-		card_detect = pcr->card_inserted | pcr->card_removed;
-		pcr->card_inserted = 0;
-		pcr->card_removed = 0;
+		card_detect = card_inserted | card_removed;
 	}
 
-	spin_unlock_irqrestore(&pcr->lock, flags);
+	mutex_unlock(&pcr->pcr_mutex);
 
 	if ((card_detect & SD_EXIST) && pcr->slots[RTSX_SD_CARD].card_event)
 		pcr->slots[RTSX_SD_CARD].card_event(
@@ -826,10 +833,6 @@  static irqreturn_t rtsx_pci_isr(int irq, void *dev_id)
 		}
 	}
 
-	if (pcr->card_inserted || pcr->card_removed)
-		schedule_delayed_work(&pcr->carddet_work,
-				msecs_to_jiffies(200));
-
 	if (int_reg & (NEED_COMPLETE_INT | DELINK_INT)) {
 		if (int_reg & (TRANS_FAIL_INT | DELINK_INT)) {
 			pcr->trans_result = TRANS_RESULT_FAIL;
@@ -842,6 +845,10 @@  static irqreturn_t rtsx_pci_isr(int irq, void *dev_id)
 		}
 	}
 
+	if (pcr->card_inserted || pcr->card_removed)
+		schedule_delayed_work(&pcr->carddet_work,
+				msecs_to_jiffies(200));
+
 	spin_unlock(&pcr->lock);
 	return IRQ_HANDLED;
 }