From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: propper support of 5 wire SPI (SPI_READY signal) Date: Sun, 21 Feb 2016 04:56:41 +0900 Message-ID: <20160220195641.GE18327@sirena.org.uk> References: <56C6DB9E.5080905@rempel-privat.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="O2gaCPMlz9o7j9TI" Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Oleksij Rempel Return-path: Content-Disposition: inline In-Reply-To: <56C6DB9E.5080905-YEK0n+YFykbzxQdaRaTXBw@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: --O2gaCPMlz9o7j9TI Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, Feb 19, 2016 at 10:08:46AM +0100, Oleksij Rempel wrote: > i'm working on a project which depends on 5 Wire SPI communication. It > is probably identical to spi-davinci.c with SPI_READY signal. Only > difference is that SPI_READY is not supported by hardware, in this case > GPIO input is used. > Currently this project implements SPI_READY and CS on top of spidev > driver. What makes it really ugly, slow and complicated. > My question is, are there any better, upstreamable way to implement it? > For example directly insight of spi framework? Any suggestions and > comments are welcome. Unless the hardware support SPI_READY a GPIO is going to be as good as it gets I think, someone else might have better ideas but nothing springs to mind for me. I'd be OK with a GPIO based implementation in the core for systems that don't have hardware support for it but I don't see anything that'd be fundamentally better in terms of system performance right now. --O2gaCPMlz9o7j9TI Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWyMT3AAoJECTWi3JdVIfQyuoH/i64uMzUc9YdJOfNb2kJmB82 QIXh8B/inz8/V9mo1ytoqKe/+k1kRbOTR0BLekSCzY7zTaDYyMpoAb0Rn8Nhbpuu 9JLB0JaYD+ESEljsg+Q9jIzrK6l/c+vm/saqlzMPV68LUCr7xLuxTR849COJy3m6 4Z0iYMWoS5cUVAu8tP6T+vhmRO3szZjSKthOoEuuC8oPQpNhmL1tCbaIX/l21xtb wQ3l3mjUk+yqvTHuLrylTpt/crUs4zOCDfwnpnq7pKHG6HG4cygHm+7C38G9Tche VWE9XD9fxqrBAsC2vueUNO8ZiKQn/FWzPdSpR2ULkCDtpISbe8IPRNEvgtMYxII= =uc+X -----END PGP SIGNATURE----- --O2gaCPMlz9o7j9TI-- -- 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