From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH v2 2/3] mtd: m25p80: consider max message size in m25p80_read Date: Sat, 24 Dec 2016 11:20:22 +0100 Message-ID: <1bd5f31a-a32e-12ce-10af-1a17955f5ab6@gmail.com> References: <6c95366c-7fcc-ef4c-033a-f9f6e152a669@gmail.com> <20160816164204.GV9347@sirena.org.uk> <2e31fbe7-bbc7-8fed-ccbf-dd9ae4d220e1@atmel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: Cyrille Pitchen , Heiner Kallweit , Mark Brown , Brian Norris , MTD Maling List , "linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" To: Michal Suchanek Return-path: In-Reply-To: Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: On 12/23/2016 10:04 PM, Michal Suchanek wrote: > Hello, Hi, > On 23 December 2016 at 19:53, Marek Vasut wrote: >> On 12/23/2016 04:33 PM, Cyrille Pitchen wrote: >>> Le 17/08/2016 à 21:09, Heiner Kallweit a écrit : >>>> Consider a message size limit when calculating the maximum amount >>>> of data that can be read. >>>> >>>> Signed-off-by: Heiner Kallweit >>> >>> Applied to git://github.com/spi-nor/linux.git >> >> Is that the concensus now that we should fix controller crappiness on >> driver level ? Or did I miss the point of this patch ? >> > > In general most controllers do have some limit on the amount of data > they can transfer at once. My observations suggest otherwise. > For some you can apply workaround at controller driver level and for > some it's not practical. > > Also for some the limit is lower so it is more likely hit. > > I guess you can call controllers that have both of these limitations > crappy but that's what's in the silicone out there. > > If you have better solution to the problem please share it in detail. I don't have a solution, but I am quite sure that if we now set a precedent that each and every device driver should take care of each and every controller's quirk, we have a lot of unpleasant work ahead of us and it will be quite the maintanance burden. The separations between device driver and controller driver has been weakened and I don't think that's good. -- Best regards, Marek Vasut -- 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