Re: [PATCH 2/2] bluetooth: raise HCI_CMD_TIMEOUT from 2s to 8s
From: Marcel Holtmann <marcel@holtmann.org>
Date: 2014-05-31 05:32:36
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Hi Alexander,
quoted hunk ↗ jump to hunk
The reasoning to do this is the following: - If a timeout occurs, the HCI-communication is broken afterwards and the dongle isn't usable anymore. - If it works after e.g. waiting 4s everyone is still happy but if it just breaks after only waiting 2s nothing is gained. - Having to wait some more seconds until an error occurs doesn't change anything. So there is no disadvantage in rasing the timeout but a great advantage in case the dongle needs more than 2s to process an HCI command. E.g. I had sometimes HCI command timeouts at boot (but never after the BT stack was successfull started). I assume the reason might be the USB-probing which happend before through the bootloader, which might have confused the dongle such that it needs a bit more time, but I'm not sure. Together with the patch which limits the timeout only to the actual time the dongle needs to process an HCI command (and doesn't include the time the kernel needs to process the answer to an HCI command), my problems were gone. Signed-off-by: Alexander Holler <redacted> --- include/net/bluetooth/hci.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index be150cf..d50fd34 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h@@ -180,7 +180,7 @@ enum {#define HCI_DISCONN_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */ #define HCI_PAIRING_TIMEOUT msecs_to_jiffies(60000) /* 60 seconds */ #define HCI_INIT_TIMEOUT msecs_to_jiffies(10000) /* 10 seconds */ -#define HCI_CMD_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */ +#define HCI_CMD_TIMEOUT msecs_to_jiffies(8000) /* 8 seconds */ #define HCI_ACL_TX_TIMEOUT msecs_to_jiffies(45000) /* 45 seconds */ #define HCI_AUTO_OFF_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */ #define HCI_POWER_OFF_TIMEOUT msecs_to_jiffies(5000) /* 5 seconds */
I think moving the command timeout handling into a delayed work struct might actually solve this problem nicely and does not force us to increase the timeout. A chip that does not respond for 8 seconds is a pretty bad chip. Regards Marcel