From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v7] serial: support for 16550A serial ports on LP-8x4x Date: Tue, 01 Mar 2016 13:06:41 +0200 Message-ID: <1456830401.13244.189.camel@linux.intel.com> References: <1456589675-25377-1-git-send-email-ynvich@gmail.com> <1456781209-11390-1-git-send-email-ynvich@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1456781209-11390-1-git-send-email-ynvich-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sergei Ianovich , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Alan Cox , Arnd Bergmann , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Greg Kroah-Hartman , Jiri Slaby , Heikki Krogerus , Peter Hurley , Masahiro Yamada , Paul Burton , Mans Rullgard , Joachim Eastwood , Scott Wood , Paul Gortmaker , Peter Ujfalusi , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , "open list:SERIAL DRIVERS" List-Id: linux-serial@vger.kernel.org On Tue, 2016-03-01 at 00:26 +0300, Sergei Ianovich wrote: > The patch adds support for 3 additional LP-8x4x built-in serial > ports. >=20 > The device can also host up to 8 extension cards with 4 serial ports > on each card for a total of 35 ports. However, I don't have > the hardware to test extension cards, so they are not supported, yet. >=20 > Signed-off-by: Sergei Ianovich > Reviewed-by: Heikki Krogerus =46ew more comments, mostly about style. > +static void lp8841_serial_set_termios(struct uart_port *port, > + struct ktermios *termios, struct ktermios *old) > +{ > +#ifdef BOTHER > + unsigned int cbaud; > +#endif > + unsigned int baud; > + unsigned int len; Since you are writing this to the register at the end maybe=C2=A0 =C2=A0- unsigned int -> u8 (write*b* =E2=80=94 exactly one byte) =C2=A0- len -> value (it's not only about data length) > + unsigned int old_csize =3D old ? old->c_cflag & CSIZE : CS8; > + struct lp8841_serial_data *data =3D port->private_data; > + > + /* We only support CS7 and CS8 */ > + while ((termios->c_cflag & CSIZE) !=3D CS7 && > + =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0(termios->c_cflag & CSIZE= ) !=3D CS8) { > + termios->c_cflag &=3D ~CSIZE; > + termios->c_cflag |=3D old_csize; > + old_csize =3D CS8; > + } > + > + serial8250_do_set_termios(port, termios, old); > + > + if ((termios->c_cflag & CSIZE) =3D=3D CS7) > + len =3D 9; > + else > + len =3D 10; > + > + if (termios->c_cflag & CSTOPB) > + len++; > + if (termios->c_cflag & PARENB) > + len++; > + if (!(termios->c_cflag & PARODD)) > + len++; > +#ifdef CMSPAR > + if (termios->c_cflag & CMSPAR) > + len++; > +#endif I don't know if someone likes it or not (up to you), but for me looks better to have ternary operators here: value +=3D (termios->c_cflag & CSTOPB) ? 1 : 0; value +=3D (termios->c_cflag & PARENB) ? 1 : 0; value +=3D (termios->c_cflag & PARODD) ? 0 : 1; #ifdef CMSPAR value +=3D (termios->c_cflag & CMSPAR) ? 1 : 0; #endif > + len -=3D 9; This one could be part of previous evaluation: =C2=A0value =3D (termios->c_cflag & CSIZE) =3D=3D CS7 ? 0 : 1; > + len &=3D 3; > + len <<=3D 3; Perhaps to define magic number (e.g. LP8841_DATA_LEN_SHIFT). > + > + baud =3D tty_termios_baud_rate(termios); > + > +#ifdef BOTHER > + /* We only support fixed rates */ > + cbaud =3D termios->c_cflag & CBAUD; > + > + if (cbaud =3D=3D BOTHER) { > + termios->c_cflag &=3D ~BOTHER; > + > + /* Don't rewrite B0 */ > + if (baud) { > + tty_termios_encode_baud_rate(termios, baud, > baud); > + baud =3D tty_termios_baud_rate(termios); > + > + /* Set sane default speed if we get 0 */ > + if (!baud) { > + baud =3D 9600; > + tty_termios_encode_baud_rate(termios > , > + baud, baud); I think you can call this unconditionally together with case > 115200. > + } > + } > + } > +#endif > + > + /* We only support up to 115200 */ > + if (baud > 115200) { > + baud =3D 115200; > + tty_termios_encode_baud_rate(termios, baud, baud); > + } Btw, can we use uart_get_baud_rate() here? > + writeb(len, data->ios_mem); > + > +} > +static int lp8841_serial_probe(struct platform_device *pdev) > +{ > + struct uart_8250_port uart =3D {}; {0} > + struct lp8841_serial_data *data; > + struct resource *mmres, *mires; > + int ret; > + > + mmres =3D platform_get_resource(pdev, IORESOURCE_MEM, 0); > + mires =3D platform_get_resource(pdev, IORESOURCE_MEM, 1); Perhaps move it down to be closer to devm_ioremap_resource() call. > + if (!mmres) > + return -ENODEV; > + > + data =3D devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + + mires =3D platform_get_resource(pdev, IORESOURCE_MEM, 1); > + data->ios_mem =3D devm_ioremap_resource(&pdev->dev, mires); > + if (IS_ERR(data->ios_mem)) > + return PTR_ERR(data->ios_mem); --=20 Andy Shevchenko Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html