On Fri, May 31, 2019 at 03:01:28PM +0100, Russell King - ARM Linux admin wrote: > On Fri, May 31, 2019 at 03:56:58PM +0200, Uwe Kleine-König wrote: > > Unless I miss something (which is quite possible given that it's quite > > some time ago I looked into mctrl_gpio) with mctrl_gpio_init_noauto() > > having a CTS-gpio is just ignored unless the modem ctrl lines are > > explicitely requestet while with mctrl_gpio_init() it results in an > > error. Isn't the error the better alternative? > > Unless the serial driver polls the modem control line status, which > the SA1100 driver continues to do in exactly the same way after this > conversion. > > Do you suggest that we just regress the driver by ripping out this > support that no one has had any problems with, and that is known to > work sufficiently in its day, just because we now don't like it? No, of course not. A nice improvement would be to teach gpio_mctrl (or serial core?) about polling. But this is of course out of scope for this patch, so I suggest to stay with mctrl_gpio_init_noauto and document the lack of irq-capability somewhere prominently such that someone who picks up converting mctrl_gpio_init_noauto to mctrl_gpio_init notices this problem before actually hitting it. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |
