diff options
author | Roger Tseng <rogerable@realtek.com> | 2015-01-21 10:09:21 (GMT) |
---|---|---|
committer | Lee Jones <lee.jones@linaro.org> | 2015-01-22 16:08:02 (GMT) |
commit | bb400d2120bd253d73661c452b18485d2d5b42dd (patch) | |
tree | 686ede6c3d3404102019913178d4a0a501c299ec /drivers/mfd | |
parent | c7f15d43a5c59c6cedb438e02032060558303589 (diff) | |
download | linux-bb400d2120bd253d73661c452b18485d2d5b42dd.tar.xz |
mfd: rtsx_usb: Defer autosuspend while card exists
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@realtek.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/mfd')
-rw-r--r-- | drivers/mfd/rtsx_usb.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/mfd/rtsx_usb.c b/drivers/mfd/rtsx_usb.c index 210d1f8..ede5024 100644 --- a/drivers/mfd/rtsx_usb.c +++ b/drivers/mfd/rtsx_usb.c @@ -681,9 +681,27 @@ static void rtsx_usb_disconnect(struct usb_interface *intf) #ifdef CONFIG_PM static int rtsx_usb_suspend(struct usb_interface *intf, pm_message_t message) { + struct rtsx_ucr *ucr = + (struct rtsx_ucr *)usb_get_intfdata(intf); + u16 val = 0; + 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; } |