From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ivan T. Ivanov" Subject: Re: [PATCH v2] spi: core: Validate lenght of the transfers in message Date: Mon, 17 Feb 2014 09:41:38 +0200 Message-ID: <1392622898.17130.8.camel@iivanov-dev> References: <1392444566-23605-1-git-send-email-iivanov@mm-sol.com> <20140216142512.GR4524@book.gsilab.sittig.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Mark Brown , linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Gerhard Sittig Return-path: In-Reply-To: <20140216142512.GR4524-kDjWylLy9wD0K7fsECOQyeGNnDKD8DIp@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Hi, On Sun, 2014-02-16 at 15:25 +0100, Gerhard Sittig wrote: > On Sat, Feb 15, 2014 at 08:09 +0200, Ivan T. Ivanov wrote: > > > > From: "Ivan T. Ivanov" > > > > SPI transfer lenght should be a power-of-two multiple > > of eight bits. > > Please re-check for "lenght" typos in subjects and commit logs > (code comments appear to be correct already). Thanks, will correct them. > > > The commit message still confuses me. You don't check that the > length of an SPI transfer has a power-of-two length in bytes. > > Instead what the check implements is IIUC > - pad "odd" bits-per-word settings before the check to full 1/2/4 > byte length specs (this is the power-of-two thing) > - the total length of the SPI transfer cannot be empty (which I'd > consider an optimization, not a violation, and may need a > separate discussion) I am not sure that I understand this one. I will say "the total length of the SPI transfer _should not_ be empty". There is no check for this currently. > - the total length of the SPI transfer must be such that each > "word" must be provided within a full 1/2/4 byte entity, with > padding bits if the bits-per-word is "odd" > > Is this a misunderstanding on my side? A terminology thing? To > me, the "SPI transfer" is the total payload and may have any > arbitrary length. What you check for is a constraint on the > transfer's length derived from or based on the "word length" > ('word' in SPI context). > > So the code may be appropriate, yet the description may need an > update, to not have the next person ask the same questions again. > I just forgot to update commit message. Will try to be more careful next time. Regards, Ivan > > virtually yours > Gerhard Sittig -- 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