From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Ungerer Subject: Re: [PATCH v2] spi: orion: support armada extended baud rates Date: Fri, 05 Sep 2014 23:11:38 +1000 Message-ID: <5409B68A.7010604@uclinux.org> References: <1409835268-29555-1-git-send-email-gerg@uclinux.org> <5409057A.6090900@uclinux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-spi , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" To: Geert Uytterhoeven Return-path: In-Reply-To: Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Hi Geert, On 05/09/14 17:36, Geert Uytterhoeven wrote: > Hi Greg, > > On Fri, Sep 5, 2014 at 2:36 AM, Greg Ungerer wrote: >>> Are the Orion rates and register bits a subset of the Armada ones? >>> I.e. does the Armada work with the Orion setup? >> The bits used by the orion are a subset (bits 0-4 of the SPI >> configuration register) of those used by the armada (bits 0-4 and >> 6-7). >> >> In practice the defined prescalar values for the orion do give >> the same divisor for the same bits set on armada. The extra bits >> on the armada let you get to lower SPI baudrates (which is more of >> a problem on the armada with its higher core clocks). > OK, so the answer is yes. > >>>> This change introduces a new device tree compatible device name >>>> "armada-spi". This is used in place of "orion-spi" on the Armada SoC >>>> parts. >>>> - compatible = "marvell,orion-spi"; >>>> + compatible = "marvell,armada-spi"; >>> If the answer to my above question is yes, you want to keep >>> "marvell,orion-spi" as a fallback. >> Do you mean like this? >> >> compatible = "marvell,orion-spi", "marvell,armada-spi"; > No, the other way around (from most-specific to least-specific): > > compatible = "marvell,armada-spi", "marvell,orion-spi" > > So the Armada version is used if available, and the Orion version > is used as a fallback. Ok, got it. Thanks. Regards Greg > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds > -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html