From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 11 Sep 2013 16:07:05 +0100 From: Mark Brown To: David Woodhouse Message-ID: <20130911150705.GT29403@sirena.org.uk> References: <20980858CB6D3A4BAE95CA194937D5E73EA0C7F4@DBDE04.ent.ti.com> <522817D7.1010206@freescale.com> <522D3B79.3060707@freescale.com> <20130909151450.GI29403@sirena.org.uk> <522EC33B.9000009@freescale.com> <20130910180704.GB29403@sirena.org.uk> <522FD78A.6080900@freescale.com> <20130911104126.GN29403@sirena.org.uk> <52304BFF.4060007@freescale.com> <1378908315.2627.392.camel@shinybook.infradead.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="rOxm5kX/3wI4eitB" Content-Disposition: inline In-Reply-To: <1378908315.2627.392.camel@shinybook.infradead.org> Subject: Re: [PATCH v3 0/8] Add the Quadspi driver for vf610-twr Cc: "devicetree@vger.kernel.org" , "computersforpeace@gmail.com" , "b44548@freescale.com" , "thomas.langer@lantiq.com" , "b18965@freescale.com" , "dedekind1@gmail.com" , "linux-doc@vger.kernel.org" , "linux-spi@vger.kernel.org" , Huang Shijie , "linux-mtd@lists.infradead.org" , "Gupta, Pekon" , "kernel@pengutronix.de" , "lznuaa@gmail.com" , "shawn.guo@linaro.org" , Huang Shijie , "linux-arm-kernel@lists.infradead.org" List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --rOxm5kX/3wI4eitB Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Sep 11, 2013 at 03:05:15PM +0100, David Woodhouse wrote: > Why can't the flash driver *provide* the required information? Yeah, that's my question too... > So far I seem to have got it into my head that we have a SPI controller > which is connected to more than one device, and we can't send commands > to one without sending to the other... and that means that we have to > send a *NOP* to the "unwanted" device. Is that right? That shouldn't be the case, SPI has a chip select line which is asserted to talk to a particular chip, while it's not asserted the slaves should ignore any activity on the bus. If activity on one slave affects another something is broken, this is the first time I noticed that being an issue but I might've missed some of the MTD side of this thread. --rOxm5kX/3wI4eitB Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.21 (GNU/Linux) iQIcBAEBAgAGBQJSMIcSAAoJELSic+t+oim9fkMQAI/Ep5QSXbRc/J33NxMd3s9c 2DrV5RgCfuYcqfOiMdTTnrRx7IYWc4yYvch72U/CtOSb4gfmdGM9ZKJAoHCpL+tD YW25DYDGLFRaBtu+hwAB9UvnvjXIwHBnGdRDuoNmnsAiPAQr8Atw2e5v/W3C3cdE husLhhKCAKMJ45NyRE/ZO1sCKXFCMMr5ZnyKR/LOjLNYD54dMV0NXTkWASK4T8fo D3qE1AfP9RsL5qMjSMHwys+WEleI9XO7JJOW3BSfLReQO7qGVKnfDN2GlRztDzvh WCtE+kk6zlVYFu0H4lFpGRPprvcYrdcbn3NJgHIpsQpb3TL9p8IkJ+HpBnpGmLV5 QD3Ny2FUKR3J1Jajyob6e4pilccnosYickj4Uf6tXvb+tuiGodhLGC0bsZIaWgEf vFevtPkCRAHBz6D5BJ31qnZAxvyduoxb2wTCXqgd7t8W1iBKUYAyMx5pueh4+H71 /kFut1tbeI8bejcMh9JRfLX2Va9Zt9uQlw5COTcdo+MPm0zJSX/TbV4jvJ3sSHRB WNIMrH8uHDsizMPvVbeb7TDuqsgUSMRvsOKgyQIryb54QlII9qkLfDLZvyZF2Jxl 2SRc803otfLIR2/pni9yq5NLUdAYoRiTpjQs2fxm4tICpiP7KI3YDMNIO1gdInDN QZog5lj2QOg/WmKD5MLE =3v7l -----END PGP SIGNATURE----- --rOxm5kX/3wI4eitB--