From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 323B5C3567B for ; Thu, 27 Feb 2020 16:36:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11AB62469C for ; Thu, 27 Feb 2020 16:36:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730313AbgB0Qgf (ORCPT ); Thu, 27 Feb 2020 11:36:35 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:39652 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729970AbgB0Qge (ORCPT ); Thu, 27 Feb 2020 11:36:34 -0500 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id EFBD52963F3; Thu, 27 Feb 2020 16:36:32 +0000 (GMT) Date: Thu, 27 Feb 2020 17:36:30 +0100 From: Boris Brezillon To: Pratyush Yadav Cc: Tudor Ambarus , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Mark Brown , Rob Herring , Mark Rutland , devicetree@vger.kernel.org, Sekhar Nori , linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, linux-mtd@lists.infradead.org Subject: Re: [PATCH v2 03/11] spi: spi-mem: allow specifying whether an op is DTR or not Message-ID: <20200227173630.40da81da@collabora.com> In-Reply-To: <20200226093703.19765-4-p.yadav@ti.com> References: <20200226093703.19765-1-p.yadav@ti.com> <20200226093703.19765-4-p.yadav@ti.com> Organization: Collabora X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 26 Feb 2020 15:06:55 +0530 Pratyush Yadav wrote: > Each phase is given a separate 'is_dtr' field so mixed protocols like > 4S-4D-4D can be supported. > > Also add the mode bits SPI_RX_DTR and SPI_TX_DTR so controllers can > specify whether they support DTR modes or not. > > Signed-off-by: Pratyush Yadav > --- > drivers/spi/spi-mem.c | 23 +++++++++++++++++++++++ > include/linux/spi/spi-mem.h | 8 ++++++++ > 2 files changed, 31 insertions(+) > > diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c > index e5a46f0eb93b..cb13e0878b95 100644 > --- a/drivers/spi/spi-mem.c > +++ b/drivers/spi/spi-mem.c > @@ -99,6 +99,16 @@ void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr, > } > EXPORT_SYMBOL_GPL(spi_controller_dma_unmap_mem_op_data); > > +static int spi_check_dtr_req(struct spi_mem *mem, bool tx) > +{ > + u32 mode = mem->spi->mode; > + > + if ((tx && (mode & SPI_TX_DTR)) || (!tx && (mode & SPI_RX_DTR))) > + return 0; > + > + return -ENOTSUPP; > +} > + > static int spi_check_buswidth_req(struct spi_mem *mem, u8 buswidth, bool tx) > { > u32 mode = mem->spi->mode; > @@ -154,6 +164,19 @@ bool spi_mem_default_supports_op(struct spi_mem *mem, > op->data.dir == SPI_MEM_DATA_OUT)) > return false; > > + if (op->cmd.is_dtr && spi_check_dtr_req(mem, true)) > + return false; > + > + if (op->addr.is_dtr && spi_check_dtr_req(mem, true)) > + return false; > + > + if (op->dummy.is_dtr && spi_check_dtr_req(mem, true)) > + return false; > + > + if (op->data.dir != SPI_MEM_NO_DATA && op->data.is_dtr && > + spi_check_dtr_req(mem, op->data.dir == SPI_MEM_DATA_OUT)) > + return false; > + Not all controllers use spi_mem_default_supports_op(). Those should be patched to reject DTR ops too. > return true; > } > EXPORT_SYMBOL_GPL(spi_mem_default_supports_op); > diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h > index af9ff2f0f1b2..4669082b4e3b 100644 > --- a/include/linux/spi/spi-mem.h > +++ b/include/linux/spi/spi-mem.h > @@ -71,6 +71,7 @@ enum spi_mem_data_dir { > * struct spi_mem_op - describes a SPI memory operation > * @cmd.buswidth: number of IO lines used to transmit the command > * @cmd.opcode: operation opcode > + * @cmd.is_dtr: whether the command opcode should be sent in DTR mode or not > * @addr.nbytes: number of address bytes to send. Can be zero if the operation > * does not need to send an address > * @addr.buswidth: number of IO lines used to transmit the address cycles > @@ -78,10 +79,13 @@ enum spi_mem_data_dir { > * Note that only @addr.nbytes are taken into account in this > * address value, so users should make sure the value fits in the > * assigned number of bytes. > + * @addr.is_dtr: whether the address should be sent in DTR mode or not > * @dummy.nbytes: number of dummy bytes to send after an opcode or address. Can > * be zero if the operation does not require dummy bytes > * @dummy.buswidth: number of IO lanes used to transmit the dummy bytes > + * @dummy.is_dtr: whether the dummy bytes should be sent in DTR mode or not > * @data.buswidth: number of IO lanes used to send/receive the data > + * @data.is_dtr: whether the data should be sent in DTR mode or not > * @data.dir: direction of the transfer > * @data.nbytes: number of data bytes to send/receive. Can be zero if the > * operation does not involve transferring data > @@ -92,21 +96,25 @@ struct spi_mem_op { > struct { > u8 buswidth; > u8 opcode; > + bool is_dtr; Hm, maybe use a bitfield here so we can pack other fields if needed. Also not convince the 'is_' prefix is useful. u8 dtr : 1; > } cmd; > > struct { > u8 nbytes; > u8 buswidth; Maybe move the dtr field here so the compiler can pack things instead of adding extra padding for the u64 alignment. u8 dtr : 1; > u64 val; > + bool is_dtr; > } addr; > > struct { > u8 nbytes; > u8 buswidth; > + bool is_dtr; > } dummy; > > struct { > u8 buswidth; > + bool is_dtr; > enum spi_mem_data_dir dir; > unsigned int nbytes; > union {