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Bluetooth: hci_ll: Replace mdelay with msleep in download_firmware 

download_firmware() is never called from atomic context.

It is only called by ll_setup() that is called only via function pointer
"->setup" used in hci_uart_setup() in drivers/bluetooth/hci_serdev.c and
drivers/bluetooth/hci_ldisc.c. hci_uart_setup() is called only
via function pointer "->setup" used in hci_dev_do_open()
in net/bluetooth/hci_core.c.
All of the above functions do not enter atomic context.

Besides, ll_setup() calls msleep() and hci_dev_do_open calls mutex_lock().
So it indicates that all the above functions call functions that can sleep.

Despite never getting called from atomic context, download_firmware()
calls mdelay() for busy wait.
That is not necessary and can be replaced with msleep to avoid busy wait.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
hifive-unleashed-5.1
Jia-Ju Bai 2018-01-27 18:03:52 +08:00 committed by Marcel Holtmann
parent 1ebbf04627
commit 06633ee14d
1 changed files with 1 additions and 1 deletions
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2
drivers/bluetooth/hci_ll.c
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@ -650,7 +650,7 @@ static int download_firmware(struct ll_device *lldev)
break;
case ACTION_DELAY: /* sleep */
bt_dev_info(lldev->hu.hdev, "sleep command in scr");
mdelay(((struct bts_action_delay *)action_ptr)->msec);
msleep(((struct bts_action_delay *)action_ptr)->msec);
break;
}
len -= (sizeof(struct bts_action) +