From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [RFC PATCH 5/8] mtd: rawnand: ams-delta: Request data port GPIO resource Date: Thu, 19 Jul 2018 08:28:34 +0200 Message-ID: <20180719082834.32827212@bbrezillon> References: <20180718235710.18242-1-jmkrzyszt@gmail.com> <20180718235710.18242-6-jmkrzyszt@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180718235710.18242-6-jmkrzyszt@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Janusz Krzysztofik Cc: Miquel Raynal , Tony Lindgren , Aaro Koskinen , Grygorii Strashko , Santosh Shilimkar , Kevin Hilman , Linus Walleij , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Artem Bityutskiy List-Id: linux-gpio@vger.kernel.org On Thu, 19 Jul 2018 01:57:07 +0200 Janusz Krzysztofik wrote: > 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, we can already > obtain exclusive access to the port by requesting an array of its GPIO > descriptors. For that to work on Amstrad Delta, respective GPIO lookup > table entries are added to the board init file. > > Signed-off-by: Janusz Krzysztofik > --- > arch/arm/mach-omap1/board-ams-delta.c | 11 ++++++++++- > drivers/mtd/nand/raw/ams-delta.c | 8 ++++++++ Can we split that in 2 patches: one adding data entries to the lookup table, and another one patching the driver to request the gpiod array. > 2 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c > index eedacdfe9725..16f7bbe47607 100644 > --- a/arch/arm/mach-omap1/board-ams-delta.c > +++ b/arch/arm/mach-omap1/board-ams-delta.c > @@ -337,7 +337,8 @@ static struct platform_device ams_delta_nand_device = { > .resource = ams_delta_nand_resources, > }; > > -#define OMAP_GPIO_LABEL "gpio-0-15" > +#define OMAP_GPIO_LABEL "gpio-0-15" > +#define OMAP_MPUIO_LABEL "mpuio" > > static struct gpiod_lookup_table ams_delta_nand_gpio_table = { > .table = { > @@ -349,6 +350,14 @@ static struct gpiod_lookup_table ams_delta_nand_gpio_table = { > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_NWE, "nwe", 0), > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_ALE, "ale", 0), > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_CLE, "cle", 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 0, "data", 0, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 1, "data", 1, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 2, "data", 2, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 3, "data", 3, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 4, "data", 4, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 5, "data", 5, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 6, "data", 6, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 7, "data", 7, 0), > { }, > }, > }; > diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c > index d7e4c9dbef67..ad62c0245458 100644 > --- a/drivers/mtd/nand/raw/ams-delta.c > +++ b/drivers/mtd/nand/raw/ams-delta.c > @@ -189,6 +189,7 @@ 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) > @@ -289,6 +290,13 @@ 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 output and set low */ > + data_gpiods = devm_gpiod_get_array(&pdev->dev, "data", GPIOD_OUT_LOW); > + 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); From mboxrd@z Thu Jan 1 00:00:00 1970 From: boris.brezillon@bootlin.com (Boris Brezillon) Date: Thu, 19 Jul 2018 08:28:34 +0200 Subject: [RFC PATCH 5/8] mtd: rawnand: ams-delta: Request data port GPIO resource In-Reply-To: <20180718235710.18242-6-jmkrzyszt@gmail.com> References: <20180718235710.18242-1-jmkrzyszt@gmail.com> <20180718235710.18242-6-jmkrzyszt@gmail.com> Message-ID: <20180719082834.32827212@bbrezillon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, 19 Jul 2018 01:57:07 +0200 Janusz Krzysztofik wrote: > 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, we can already > obtain exclusive access to the port by requesting an array of its GPIO > descriptors. For that to work on Amstrad Delta, respective GPIO lookup > table entries are added to the board init file. > > Signed-off-by: Janusz Krzysztofik > --- > arch/arm/mach-omap1/board-ams-delta.c | 11 ++++++++++- > drivers/mtd/nand/raw/ams-delta.c | 8 ++++++++ Can we split that in 2 patches: one adding data entries to the lookup table, and another one patching the driver to request the gpiod array. > 2 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c > index eedacdfe9725..16f7bbe47607 100644 > --- a/arch/arm/mach-omap1/board-ams-delta.c > +++ b/arch/arm/mach-omap1/board-ams-delta.c > @@ -337,7 +337,8 @@ static struct platform_device ams_delta_nand_device = { > .resource = ams_delta_nand_resources, > }; > > -#define OMAP_GPIO_LABEL "gpio-0-15" > +#define OMAP_GPIO_LABEL "gpio-0-15" > +#define OMAP_MPUIO_LABEL "mpuio" > > static struct gpiod_lookup_table ams_delta_nand_gpio_table = { > .table = { > @@ -349,6 +350,14 @@ static struct gpiod_lookup_table ams_delta_nand_gpio_table = { > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_NWE, "nwe", 0), > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_ALE, "ale", 0), > GPIO_LOOKUP(LATCH2_LABEL, LATCH2_PIN_NAND_CLE, "cle", 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 0, "data", 0, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 1, "data", 1, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 2, "data", 2, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 3, "data", 3, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 4, "data", 4, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 5, "data", 5, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 6, "data", 6, 0), > + GPIO_LOOKUP_IDX(OMAP_MPUIO_LABEL, 7, "data", 7, 0), > { }, > }, > }; > diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c > index d7e4c9dbef67..ad62c0245458 100644 > --- a/drivers/mtd/nand/raw/ams-delta.c > +++ b/drivers/mtd/nand/raw/ams-delta.c > @@ -189,6 +189,7 @@ 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) > @@ -289,6 +290,13 @@ 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 output and set low */ > + data_gpiods = devm_gpiod_get_array(&pdev->dev, "data", GPIOD_OUT_LOW); > + 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);