From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753530AbbJ0Hmp (ORCPT ); Tue, 27 Oct 2015 03:42:45 -0400 Received: from down.free-electrons.com ([37.187.137.238]:59688 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753210AbbJ0HmD (ORCPT ); Tue, 27 Oct 2015 03:42:03 -0400 Date: Tue, 27 Oct 2015 08:42:00 +0100 From: Boris Brezillon To: Brian Norris Cc: , , Ezequiel Garcia , Marek Vasut , Scott Wood , Josh Wu , Robert Jarzmik , Kyungmin Park , Han Xu , Huang Shijie Subject: Re: [PATCH 1/5] mtd: ofpart: grab device tree node directly from master device node Message-ID: <20151027084200.2434180f@bbrezillon> In-Reply-To: <1445913070-17950-2-git-send-email-computersforpeace@gmail.com> References: <1445913070-17950-1-git-send-email-computersforpeace@gmail.com> <1445913070-17950-2-git-send-email-computersforpeace@gmail.com> X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.27; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Brian, On Mon, 26 Oct 2015 19:31:06 -0700 Brian Norris wrote: > It seems more logical to use a device node directly associated with the > MTD master device (i.e., mtd->dev.of_node field) rather than requiring > auxiliary partition parser information to be passed in by the driver in > a separate struct. > > This patch supports the mtd->dev.of_node field, deprecates the parser > data 'of_node' field, and begins using the new convention for nand_base. > Other NAND driver conversions may now follow. > > Additional side benefit to assigning mtd->dev.of_node rather than using > parser data: the driver core will automatically create a device -> node > symlink for us. I like the idea, but how about pushing the solution even further and killing the ->flash_node field which AFAICT is rendered useless by your patch? Best Regards, Boris > > Signed-off-by: Brian Norris > --- > drivers/mtd/nand/nand_base.c | 3 +++ > drivers/mtd/ofpart.c | 18 ++++++++++-------- > drivers/mtd/spi-nor/spi-nor.c | 1 + > include/linux/mtd/partitions.h | 4 +++- > 4 files changed, 17 insertions(+), 9 deletions(-) > > diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c > index cc74142938b0..d2e7fee2ac37 100644 > --- a/drivers/mtd/nand/nand_base.c > +++ b/drivers/mtd/nand/nand_base.c > @@ -3990,6 +3990,9 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips, > int ret; > > if (chip->flash_node) { > + /* MTD can automatically handle DT partitions, etc. */ > + mtd->dev.of_node = chip->flash_node; > + > ret = nand_dt_init(mtd, chip, chip->flash_node); > if (ret) > return ret; > diff --git a/drivers/mtd/ofpart.c b/drivers/mtd/ofpart.c > index aa26c32e1bc2..a5dfd73cfc7d 100644 > --- a/drivers/mtd/ofpart.c > +++ b/drivers/mtd/ofpart.c > @@ -35,10 +35,11 @@ static int parse_ofpart_partitions(struct mtd_info *master, > int nr_parts, i; > > > - if (!data) > - return 0; > - > - node = data->of_node; > + /* > + * of_node can be provided through auxiliary parser data or (preferred) > + * by assigning the master device > + */ > + node = data && data->of_node ? data->of_node : master->dev.of_node; > if (!node) > return 0; > > @@ -120,10 +121,11 @@ static int parse_ofoldpart_partitions(struct mtd_info *master, > } *part; > const char *names; > > - if (!data) > - return 0; > - > - dp = data->of_node; > + /* > + * of_node can be provided through auxiliary parser data or (preferred) > + * by assigning the master device > + */ > + dp = data && data->of_node ? data->of_node : master->dev.of_node; > if (!dp) > return 0; > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index 49883905a434..8f9080c6db63 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -1258,6 +1258,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > mtd->flags |= MTD_NO_ERASE; > > mtd->dev.parent = dev; > + mtd->dev.of_node = np; > nor->page_size = info->page_size; > mtd->writebufsize = nor->page_size; > > diff --git a/include/linux/mtd/partitions.h b/include/linux/mtd/partitions.h > index 6a35e6de5da1..e742f34b67eb 100644 > --- a/include/linux/mtd/partitions.h > +++ b/include/linux/mtd/partitions.h > @@ -56,7 +56,9 @@ struct device_node; > /** > * struct mtd_part_parser_data - used to pass data to MTD partition parsers. > * @origin: for RedBoot, start address of MTD device > - * @of_node: for OF parsers, device node containing partitioning information > + * @of_node: for OF parsers, device node containing partitioning information. > + * This field is deprecated, as the device node should simply be > + * assigned to the master struct device. > */ > struct mtd_part_parser_data { > unsigned long origin; -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com