From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH 3/4] tty: serial: bcm63xx_uart: add support for DT probing Date: Thu, 20 Feb 2014 08:18:41 -0800 Message-ID: <53062AE1.6000204@gmail.com> References: <1392852167-26243-1-git-send-email-f.fainelli@gmail.com> <4709421.TpqQL1VssO@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <4709421.TpqQL1VssO@wuerfel> Sender: linux-serial-owner@vger.kernel.org To: Arnd Bergmann , Jonas Gorski Cc: linux-serial@vger.kernel.org, "devicetree@vger.kernel.org" , Maxime Bizon , Greg Kroah-Hartman List-Id: devicetree@vger.kernel.org Hi Arnd, Le 20/02/2014 04:16, Arnd Bergmann a =E9crit : > On Thursday 20 February 2014 11:59:04 Jonas Gorski wrote: >> On Thu, Feb 20, 2014 at 2:29 AM, Florian Fainelli wrote: >>> 2014-02-19 16:00 GMT-08:00 Jonas Gorski : >>>> On Thu, Feb 20, 2014 at 12:22 AM, Florian Fainelli wrote: >>>>> @@ -857,6 +861,12 @@ static int bcm_uart_remove(struct platform_d= evice *pdev) >>>>> return 0; >>>>> } >>>>> >>>>> +static const struct of_device_id bcm63xx_of_match[] =3D { >>>>> + { .compatible =3D "brcm,bcm63xx-uart" }, >>>> >>>> From my understanding, this should be "brcm,bcm6345-uart", becaus= e >>>> this kind of uart appeared first on bcm6345 (well, maybe bcm6335, = no >>>> idea which one of these two was first, but the latter was never >>>> supported in mainline anyway). >>> >>> That's right, in fact, I think it might be desirable to handle both >>> compatible string, just as a hint that it is compatible with the >>> entire bcm63xx family. Would that work for you? >> >> I think using a "generic" compatible string is rather frowned upon >> (what do you do if there is eventually a bcm63xx chip with an >> incompatible uart?), but I'm no device tree expert. > > It's ok to have a generic name, it's wildcards like the xx above > that we try to avoid, since that breaks down when you get another > device in the same SoC family that is not compatible. This is differe= nt > from the Linux way of naming things. > > brcm,bcm6345-uart sounds good, if that is the closest we can get > to a generic name, working under the assumption that it's the oldest > implementation of this UART. Ideally we'd find someone with access > to the design documents of the SoC to tell us what the UART is really > called by whoever designed it (which may not even be Broadcom). This is just called an uart, it does not have any specific project name= =20 as far as I could see, and BCM6345 was indeed the very first SoC using = it. > > If we think there may be some level of variation between the UARTS > in the various bcm63xx SoCs, it would be good to list both the > specific model of the SoC as well as the generic name in "compatible"= , > so the driver can later detect those differences without requiring > an updated DT. Makes sense. So far this UART has been not modified (as far as a=20 programmer may be concerned) since its very first design in a BCM6345. > > A BCM63138 for instance could list this as > > compatible =3D "brcm,bcm62138-uart", "brcm-bcm6345-uart"; > > Arnd > -- To unsubscribe from this list: send the line "unsubscribe linux-serial"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html