On Wed, Nov 25, 2015 at 10:26:12PM +0200, Andy Shevchenko wrote:
> On Wed, Nov 25, 2015 at 12:28 AM, Konstantin Shkolnyy
> <konstantin.shkolnyy@xxxxxxxxx> wrote:
> > Added tx_empty callback needed for generic wait-until-sent support.
> > Without this function, when the port is closed usbserial can't know that
> > there are still data in the chip's transmit FIFO. The chip gets disabled
> > and untransmitted data lost. When the actual byte count is reported by
> > tx-empty the close can be delayed until all data are sent.
> >
>
> > /*
> > + * Read how many bytes are waiting in the TX queue.
> > + */
>
> One line?
Not necessarily for a function header.
> > +static bool cp210x_tx_empty(struct usb_serial_port *port)
> > +{
> > + int err;
> > + u32 count;
> > +
> > + err = cp210x_get_tx_queue_byte_count(port, &count);
>
> > + if (!err && count)
> > + return false;
> > +
> > + return true;
>
> return err || !count;
Nah, I don't consider that an improvement.
I prefer separating the error and success paths, for example:
if (err)
return true;
return !count;
but the current code is also ok.
> Btw, can be count left uninitialized?
Yes, but that's not an issue. Clearly separating the success and errors
paths as I suggested above would make that more obvious however.
I'll fix that up before applying.
Thanks,
Johan
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
