On Thu, 2017-05-11 at 16:13 +0200, Greg Kroah-Hartman wrote:
> 4.4-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Johan Hovold <johan@xxxxxxxxxx>
>
> commit 16620b483eaf7750413bae472f4363b6b959fcaa upstream.
>
> Interface numbers do not change when enabling alternate settings as
> comment and code in this driver suggested.
>
> Remove the confusing comment and redundant retrieval of the interface
> number in probe, while simplifying and renaming the interface-number
> helper.
This looks like cleanup with no functional impact, so unless it's needed
as preparation for something else I think it should be dropped.
Ben.
> Fixes: 4db2299da213 ("sierra: driver interface blacklisting")
> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>
> ---
> drivers/usb/serial/sierra.c | 28 +++++-----------------------
> 1 file changed, 5 insertions(+), 23 deletions(-)
>
> --- a/drivers/usb/serial/sierra.c
> +++ b/drivers/usb/serial/sierra.c
> @@ -137,24 +137,9 @@ static int is_himemory(const u8 ifnum,
> return 0;
> }
>
> -static int sierra_calc_interface(struct usb_serial *serial)
> +static u8 sierra_interface_num(struct usb_serial *serial)
> {
> - int interface;
> - struct usb_interface *p_interface;
> - struct usb_host_interface *p_host_interface;
> -
> - /* Get the interface structure pointer from the serial struct */
> - p_interface = serial->interface;
> -
> - /* Get a pointer to the host interface structure */
> - p_host_interface = p_interface->cur_altsetting;
> -
> - /* read the interface descriptor for this active altsetting
> - * to find out the interface number we are on
> - */
> - interface = p_host_interface->desc.bInterfaceNumber;
> -
> - return interface;
> + return serial->interface->cur_altsetting->desc.bInterfaceNumber;
> }
>
> static int sierra_probe(struct usb_serial *serial,
> @@ -165,7 +150,7 @@ static int sierra_probe(struct usb_seria
> u8 ifnum;
>
> udev = serial->dev;
> - ifnum = sierra_calc_interface(serial);
> + ifnum = sierra_interface_num(serial);
>
> /*
> * If this interface supports more than 1 alternate
> @@ -178,9 +163,6 @@ static int sierra_probe(struct usb_seria
> usb_set_interface(udev, ifnum, 1);
> }
>
> - /* ifnum could have changed - by calling usb_set_interface */
> - ifnum = sierra_calc_interface(serial);
> -
> if (is_blacklisted(ifnum,
> (struct sierra_iface_info *)id->driver_info)) {
> dev_dbg(&serial->dev->dev,
> @@ -342,7 +324,7 @@ static int sierra_send_setup(struct usb_
>
> /* If composite device then properly report interface */
> if (serial->num_ports == 1) {
> - interface = sierra_calc_interface(serial);
> + interface = sierra_interface_num(serial);
> /* Control message is sent only to interfaces with
> * interrupt_in endpoints
> */
> @@ -916,7 +898,7 @@ static int sierra_port_probe(struct usb_
> /* Determine actual memory requirements */
> if (serial->num_ports == 1) {
> /* Get interface number for composite device */
> - ifnum = sierra_calc_interface(serial);
> + ifnum = sierra_interface_num(serial);
> himemoryp = &typeB_interface_list;
> } else {
> /* This is really the usb-serial port number of the interface
>
>
>
--
Ben Hutchings
Software Developer, Codethink Ltd.