Re: [PATCH 1/3] USB: serial: ports: add minor and port number

[Johan Hovold <jhovold@gmail.com>]

On Wed, Jun 05, 2013 at 10:55:39AM -0700, Greg KH wrote:
> From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> The usb_serial_port structure had the number field, which was the minor
> number for the port, which almost no one really cared about.  They
> really wanted the number of the port within the device, which you had to
> subtract from the minor of the parent usb_serial_device structure.  To
> clean this up, provide the real minor number of the port, and the number
> of the port within the serial device separately, as these numbers might
> not be related in the future.
> 
> Bonus is that this cleans up a lot of logic in the drivers, and saves
> lines overall.
> 
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

> --- a/drivers/usb/serial/io_edgeport.c
> +++ b/drivers/usb/serial/io_edgeport.c

> @@ -2302,7 +2293,7 @@ static int send_cmd_write_baud_rate(stru
>  
>  	/* Restore original value to disable access to divisor latch */
>  	MAKE_CMD_WRITE_REG(&currCmd, &cmdLen, number, LCR,
> -						edge_port->shadowLCR);
> +			   edge_port->shadowLCR);

Unintended indentation change?

>  	status = write_cmd_usb(edge_port, cmdBuffer, cmdLen);
>  	if (status) {

> --- a/drivers/usb/serial/whiteheat.c
> +++ b/drivers/usb/serial/whiteheat.c

> @@ -649,7 +649,7 @@ static void firm_setup_port(struct tty_s
>  	struct whiteheat_port_settings port_settings;
>  	unsigned int cflag = tty->termios.c_cflag;
>  
> -	port_settings.port = port->number + 1;
> +	port_settings.port = port->port_number + 1;

This is a bug that should be fixed separately and backported, as it
prevents port configuration (e.g. set_termios) for ports with minor
number greater than 0.

I took the liberty to prepare a separate patch for v3.10, which you
could rebase the series on.

>  	/* get the byte size */
>  	switch (cflag & CSIZE) {

> --- a/include/linux/usb/serial.h
> +++ b/include/linux/usb/serial.h
> @@ -37,7 +37,8 @@
>   * @serial: pointer back to the struct usb_serial owner of this port.
>   * @port: pointer to the corresponding tty_port for this port.
>   * @lock: spinlock to grab when updating portions of this structure.
> - * @number: the number of the port (the minor number).
> + * @minor: the minor number of the port
> + * @port_number: the port number of this struct usb_serial_device (starts at 0)

Maybe 

	@port_number: the struct usb_serial port number of this port (starts at 0)

or something similar, would be more clear?

>   * @interrupt_in_buffer: pointer to the interrupt in buffer for this port.
>   * @interrupt_in_urb: pointer to the interrupt in struct urb for this port.
>   * @interrupt_in_endpointAddress: endpoint address for the interrupt in pipe

Looks good otherwise.

Thanks,
Johan