From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753222Ab3GBP6k (ORCPT ); Tue, 2 Jul 2013 11:58:40 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:46208 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752152Ab3GBP6j (ORCPT ); Tue, 2 Jul 2013 11:58:39 -0400 Date: Tue, 2 Jul 2013 18:58:27 +0300 From: Felipe Balbi To: Sourav Poddar CC: , , , , , , Subject: Re: [PATCHv2] drivers: spi: Add qspi flash controller Message-ID: <20130702155827.GA7626@arwen.pp.htv.fi> Reply-To: References: <1372755399-21769-1-git-send-email-sourav.poddar@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="xHFwDpU9dbj6ez1V" Content-Disposition: inline In-Reply-To: <1372755399-21769-1-git-send-email-sourav.poddar@ti.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --xHFwDpU9dbj6ez1V Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, Alright, so I spent some time looking at the SPI framework and : On Tue, Jul 02, 2013 at 02:26:39PM +0530, Sourav Poddar wrote: > +static int dra7xxx_qspi_start_transfer_one(struct spi_master *master, > + struct spi_message *m) > +{ > + struct dra7xxx_qspi *qspi =3D spi_master_get_devdata(master); > + struct spi_device *spi =3D m->spi; > + struct spi_transfer *t; > + int status =3D 0; > + int flags =3D 0; > + > + /* setup command reg */ > + qspi->cmd =3D 0; > + qspi->cmd |=3D QSPI_WLEN(8); this m->spi->bits_per_word; > + qspi->cmd |=3D QSPI_EN_CS(0); this should be m->spi->chip_select; > + qspi->cmd |=3D 0xfff; this will be a little tricky to count... because, I believe it should be something like: int count =3D 0; list_for_each_entry(t, &m->transfers, transfer_list) count +=3D t->len; frame_length =3D DIV_ROUND_UP(count, m->spi->bits_per_word); /* up to 4096 words */ frame_length =3D clamp(frame_length, 4096); qspi->cmd |=3D QSPI_FRAME_LENGTH(DIV_ROUND_UP(count, frame_length)); Now, it would've been better if SPI framework would already give us some sort of total_length field in struct spi_message which would be the sum of all spi_transfers. > + /* setup device control reg */ > + qspi->dc =3D 0; > + > + if (spi->mode & SPI_CPHA) > + qspi->dc |=3D QSPI_CKPHA(0); > + if (spi->mode & SPI_CPOL) > + qspi->dc |=3D QSPI_CKPOL(0); > + if (spi->mode & SPI_CS_HIGH) > + qspi->dc |=3D QSPI_CSPOL(0); all of these zeroes being passed to these macros should be m->spi->chip_select --=20 balbi --xHFwDpU9dbj6ez1V Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJR0vijAAoJEIaOsuA1yqREp2kP/32rbawdCtptwh5qLxCUeHsq t8dX+o2jD60H1YxzC7ezstOAKwoJTSlk/oKELw4TFZP6rWjTwkM1FiYXoeP/s0Qu pmH9XsF7Pmswj4pTq9DPOv/BseOF3ZSezYr3kGFE6DS2KNWGY2gpmoGgV8l76nyE zwvspPhmQITrpSyJ9WDZ+1bI6iMwRPGLL1/k6c4h6+65q6ml9kD5Xv/ZY2D9lyHJ KR9BbDETRF6lkNr4/elBE4zFCcUFsdDvQar45QWCwhHInk0BtkCKoareKdKQ3nAL xFWj8V5Hr9ARbWhk1tEUIjYBr8Y8l4ttd+iUGWvNM3cRKfYxRWu8VZpNEUERNiVp RtJE+dtnBsvbQo5C2q1HAU6AQlsfhJDSYS3/ZyLji1Ox+i/Sxo5KzznBuL3hqqU9 gofPP9PQ2xSbEn9q4orCM2x14bqhRuTCeweMskYs6UK82Vr2hEzYGL1EPg+vmdpn wpWiSZz0syunxSMrp2X2olWcbveE4+eUyLqCwDhnUPnFe8y63CgvMZwG8Y2Kqo7i B2j18wjtuFs3C/lSMb/r9EMWVIcBuTp6h1flzQAtD7v1i71a2RYCgaONem/9xdUs KYkFgoT5yPU5xgaRcSN2vuMI7u5+KG7Vq9mwrvVlkCkPbyip4F8h7xKlcSffs4gM isRaXBE/C/pY/8JTTQGB =mXSm -----END PGP SIGNATURE----- --xHFwDpU9dbj6ez1V--