A card insertion happens after the lastest polling before reader is
suspended may never have a chance to be detected. Under current 1-HZ
polling interval setting in mmc_core, the worst case of such
undetectablility is about 1 second.
To further reduce the undetectability, detect card slot again in suspend
method and defer the autosuspend if the slot is loaded. The default 2
second autosuspend delay of USB subsystem should let the next polling
detects the card.
Signed-off-by: Roger Tseng <rogerable@xxxxxxxxxxx>
---
drivers/mfd/rtsx_usb.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/mfd/rtsx_usb.c b/drivers/mfd/rtsx_usb.c
index 076694126e5d..63883fd025c0 100644
--- a/drivers/mfd/rtsx_usb.c
+++ b/drivers/mfd/rtsx_usb.c
@@ -687,6 +687,20 @@ static int rtsx_usb_suspend(struct usb_interface *intf, pm_message_t message)
dev_dbg(&intf->dev, "%s called with pm message 0x%04x\n",
__func__, message.event);
+ if (PMSG_IS_AUTO(message)) {
+ if (mutex_trylock(&ucr->dev_mutex)) {
+ rtsx_usb_get_card_status(ucr, &val);
+ mutex_unlock(&ucr->dev_mutex);
+
+ /* Defer the autosuspend if card exists */
+ if (val & (SD_CD | MS_CD))
+ return -EAGAIN;
+ } else {
+ /* There is an ongoing operation*/
+ return -EAGAIN;
+ }
+ }
+
return 0;
}
--
2.1.3
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