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| author | Alan Stern <stern@rowland.harvard.edu> | 2011-02-23 15:28:18 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-23 13:03:46 -0700 |
| commit | 366a91fbe3eeaf11c7bc380e854c7096bcb976dd (patch) | |
| tree | c58efa89519be35bf2dbc63916a15ad754c3f8a1 /include | |
| parent | 2ac31a250c7d0cf642cc183bcf55e571ada867f6 (diff) | |
USB: serial drivers need to use larger bulk-in buffers
commit 969e3033ae7733a0af8f7742ca74cd16c0857e71 upstream.
When a driver doesn't know how much data a device is going to send,
the buffer size should be at least as big as the endpoint's maxpacket
value. The serial drivers don't follow this rule; many of them
request only 256-byte bulk-in buffers. As a result, they suffer
overflow errors if a high-speed device wants to send a lot of data,
because high-speed bulk endpoints are required to have a maxpacket
size of 512.
This patch (as1450) fixes the problem by using the driver's
bulk_in_size value as a minimum, always allocating buffers no smaller
than the endpoint's maxpacket size.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Flynn Marquardt <flynn@flynnux.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/usb/serial.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h index c9049139a7a..45f3b9db425 100644 --- a/include/linux/usb/serial.h +++ b/include/linux/usb/serial.h @@ -191,7 +191,8 @@ static inline void usb_set_serial_data(struct usb_serial *serial, void *data) * @id_table: pointer to a list of usb_device_id structures that define all * of the devices this structure can support. * @num_ports: the number of different ports this device will have. - * @bulk_in_size: bytes to allocate for bulk-in buffer (0 = end-point size) + * @bulk_in_size: minimum number of bytes to allocate for bulk-in buffer + * (0 = end-point size) * @bulk_out_size: bytes to allocate for bulk-out buffer (0 = end-point size) * @calc_num_ports: pointer to a function to determine how many ports this * device has dynamically. It will be called after the probe() |