From mboxrd@z Thu Jan 1 00:00:00 1970 From: Janusz Krzysztofik Subject: [RFC PATCH v2 04/12] mtd: rawnand: ams-delta: request data port GPIO resource Date: Tue, 7 Aug 2018 00:29:10 +0200 Message-ID: <20180806222918.12644-5-jmkrzyszt@gmail.com> References: <20180718235710.18242-1-jmkrzyszt@gmail.com> <20180806222918.12644-1-jmkrzyszt@gmail.com> Return-path: In-Reply-To: <20180806222918.12644-1-jmkrzyszt@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Boris Brezillon , Linus Walleij Cc: Jonathan Corbet , Miquel Raynal , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Tony Lindgren , Aaro Koskinen , linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-mtd@lists.infradead.org, linux-doc@vger.kernel.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Janusz Krzysztofik List-Id: linux-omap@vger.kernel.org Data port used by the driver is actually an OMAP MPUIO device, already under control of gpio-omap driver. For that reason we used to not request the memory region of the port as that would fail because the region is already busy. Despite that, we are still accessing the port by just ioremapping it and performing read/write operations. Moreover, we are doing that without any proteciton from other users legally manipulating the port pins over GPIO API. The plan is to convert the driver to access the port over functions exposed by the gpio-omap driver. Before that happens, already prevent from other users accessing the port pins by requesting an array of its GPIO descriptors. Signed-off-by: Janusz Krzysztofik --- drivers/mtd/nand/raw/ams-delta.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c index 48233d638d2a..09d6901fc94d 100644 --- a/drivers/mtd/nand/raw/ams-delta.c +++ b/drivers/mtd/nand/raw/ams-delta.c @@ -161,6 +161,7 @@ static int ams_delta_init(struct platform_device *pdev) struct mtd_info *mtd; struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); void __iomem *io_base; + struct gpio_descs *data_gpiods; int err = 0; if (!res) @@ -261,6 +262,13 @@ static int ams_delta_init(struct platform_device *pdev) dev_err(&pdev->dev, "CLE GPIO request failed (%d)\n", err); goto out_mtd; } + /* Request array of data pins, initialize them as input */ + data_gpiods = devm_gpiod_get_array(&pdev->dev, "data", GPIOD_IN); + if (IS_ERR(data_gpiods)) { + err = PTR_ERR(data_gpiods); + dev_err(&pdev->dev, "data GPIO request failed: %d\n", err); + goto out_mtd; + } /* Scan to find existence of the device */ err = nand_scan(mtd, 1); -- 2.16.4