4.9-stable review patch. If anyone has any objections, please let me know.
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From: Chanwoo Choi cw00.choi@samsung.com
[ Upstream commit 01b4c9a1ae07a25d208cad0da7dd288007a22984 ]
This patch removes the potential problem of extcon_register_notifier() when edev parameter is NULL. When edev is NULL, this function returns the first extcon device which includes the sepecific external connector of second paramter. But, it don't guarantee the same operation in all cases. To remove this confusion and potential problem, this patch fixes it.
Signed-off-by: Chanwoo Choi cw00.choi@samsung.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/extcon/extcon.c | 35 ++++++++--------------------------- 1 file changed, 8 insertions(+), 27 deletions(-)
--- a/drivers/extcon/extcon.c +++ b/drivers/extcon/extcon.c @@ -906,35 +906,16 @@ int extcon_register_notifier(struct extc unsigned long flags; int ret, idx = -EINVAL;
- if (!nb) + if (!edev || !nb) return -EINVAL;
- if (edev) { - idx = find_cable_index_by_id(edev, id); - if (idx < 0) - return idx; - - spin_lock_irqsave(&edev->lock, flags); - ret = raw_notifier_chain_register(&edev->nh[idx], nb); - spin_unlock_irqrestore(&edev->lock, flags); - } else { - struct extcon_dev *extd; - - mutex_lock(&extcon_dev_list_lock); - list_for_each_entry(extd, &extcon_dev_list, entry) { - idx = find_cable_index_by_id(extd, id); - if (idx >= 0) - break; - } - mutex_unlock(&extcon_dev_list_lock); - - if (idx >= 0) { - edev = extd; - return extcon_register_notifier(extd, id, nb); - } else { - ret = -ENODEV; - } - } + idx = find_cable_index_by_id(edev, id); + if (idx < 0) + return idx; + + spin_lock_irqsave(&edev->lock, flags); + ret = raw_notifier_chain_register(&edev->nh[idx], nb); + spin_unlock_irqrestore(&edev->lock, flags);
return ret; }