lkml.org 
[lkml]   [2015]   [Jul]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] extcon: Fix extcon_cable_get_state() from getting old state after notification
Date
Currently the extcon code notifiers the interested listeners
before it updates the extcon state with the new state.
This will cause the listeners that use extcon_cable_get_state()
to get the stale state and loose the new state.

Fix this by first changing the extcon state variable and then
notifying listeners.

Signed-off-by: Roger Quadros <rogerq@ti.com>
---
drivers/extcon/extcon.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
index 868c6e2..26d1e1e 100644
--- a/drivers/extcon/extcon.c
+++ b/drivers/extcon/extcon.c
@@ -275,19 +275,25 @@ int extcon_update_state(struct extcon_dev *edev, u32 mask, u32 state)
spin_lock_irqsave(&edev->lock, flags);

if (edev->state != ((edev->state & ~mask) | (state & mask))) {
+ u32 old_state;
+
if (check_mutually_exclusive(edev, (edev->state & ~mask) |
(state & mask))) {
spin_unlock_irqrestore(&edev->lock, flags);
return -EPERM;
}

+ old_state = edev->state;
+ edev->state &= ~mask;
+ edev->state |= state & mask;
+
for (index = 0; index < edev->max_supported; index++) {
- if (is_extcon_changed(edev->state, state, index, &attached))
- raw_notifier_call_chain(&edev->nh[index], attached, edev);
+ if (is_extcon_changed(old_state, edev->state, index,
+ &attached))
+ raw_notifier_call_chain(&edev->nh[index],
+ attached, edev);
}

- edev->state &= ~mask;
- edev->state |= state & mask;

/* This could be in interrupt handler */
prop_buf = (char *)get_zeroed_page(GFP_ATOMIC);
--
2.1.4


\
 
 \ /
  Last update: 2015-07-06 17:01    [W:0.101 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site