From patchwork Sun Dec 18 10:00:49 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jamie Iles X-Patchwork-Id: 132058 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2B101B6FFC for ; Sun, 18 Dec 2011 21:02:42 +1100 (EST) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1RcDYB-0001D5-IL; Sun, 18 Dec 2011 10:00:59 +0000 Received: from mail-we0-f177.google.com ([74.125.82.177]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1RcDY8-0001Cr-TT for linux-mtd@lists.infradead.org; Sun, 18 Dec 2011 10:00:58 +0000 Received: by wera10 with SMTP id a10so1121681wer.36 for ; Sun, 18 Dec 2011 02:00:53 -0800 (PST) Received: by 10.216.134.162 with SMTP id s34mr5407996wei.59.1324202453480; Sun, 18 Dec 2011 02:00:53 -0800 (PST) Received: from localhost (cpc1-chap8-2-0-cust194.aztw.cable.virginmedia.com. [94.169.120.195]) by mx.google.com with ESMTPS id dw6sm20836774wib.12.2011.12.18.02.00.51 (version=TLSv1/SSLv3 cipher=OTHER); Sun, 18 Dec 2011 02:00:51 -0800 (PST) From: Jamie Iles To: linux-mtd@lists.infradead.org Subject: [PATCH] mtd: gpio-nand: add device tree bindings Date: Sun, 18 Dec 2011 10:00:49 +0000 Message-Id: <1324202449-13820-1-git-send-email-jamie@jamieiles.com> X-Mailer: git-send-email 1.7.5.4 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Scott Wood , Jamie Iles , David Woodhouse , Grant Likely , Artem Bityutskiy X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Add device tree bindings so that the gpio-nand driver may be instantiated from the device tree. This also allows the partitions to be specified in the device tree. v7: - restore runtime device tree/non device tree detection v6: - convert to mtd_device_parse_register() v5: - fold dt config helpers into a single gpio_nand_of_get_config() v4: - get io sync address from gpio-control-nand,io-sync-reg property rather than a resource - clarified a few details in the binding v3: - remove redundant cast and a couple of whitespace/naming changes v2: - add CONFIG_OF guards for non-dt platforms - compatible becomes gpio-control-nand - clarify some binding details Cc: David Woodhouse Cc: Artem Bityutskiy Cc: Scott Wood Cc: Grant Likely Signed-off-by: Jamie Iles --- .../devicetree/bindings/mtd/gpio-control-nand.txt | 44 ++++++++ drivers/mtd/nand/gpio.c | 115 ++++++++++++++++++-- 2 files changed, 152 insertions(+), 7 deletions(-) create mode 100644 Documentation/devicetree/bindings/mtd/gpio-control-nand.txt diff --git a/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt new file mode 100644 index 0000000..719f4dc --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt @@ -0,0 +1,44 @@ +GPIO assisted NAND flash + +The GPIO assisted NAND flash uses a memory mapped interface to +read/write the NAND commands and data and GPIO pins for the control +signals. + +Required properties: +- compatible : "gpio-control-nand" +- reg : should specify localbus chip select and size used for the chip. The + resource describes the data bus connected to the NAND flash and all accesses + are made in native endianness. +- #address-cells, #size-cells : Must be present if the device has sub-nodes + representing partitions. +- gpios : specifies the gpio pins to control the NAND device. nwp is an + optional gpio and may be set to 0 if not present. + +Optional properties: +- bank-width : Width (in bytes) of the device. If not present, the width + defaults to 1 byte. +- chip-delay : chip dependent delay for transferring data from array to + read registers (tR). If not present then a default of 20us is used. +- gpio-control-nand,io-sync-reg : A 64-bit physical address for a read + location used to guard against bus reordering with regards to accesses to + the GPIO's and the NAND flash data bus. If present, then after changing + GPIO state and before and after command byte writes, this register will be + read to ensure that the GPIO accesses have completed. + +Examples: + +gpio-nand@1,0 { + compatible = "gpio-control-nand"; + reg = <1 0x0000 0x2>; + #address-cells = <1>; + #size-cells = <1>; + gpios = <&banka 1 0 /* rdy */ + &banka 2 0 /* nce */ + &banka 3 0 /* ale */ + &banka 4 0 /* cle */ + 0 /* nwp */>; + + partition@0 { + ... + }; +}; diff --git a/drivers/mtd/nand/gpio.c b/drivers/mtd/nand/gpio.c index 2c2060b..d4b5609 100644 --- a/drivers/mtd/nand/gpio.c +++ b/drivers/mtd/nand/gpio.c @@ -27,6 +27,9 @@ #include #include #include +#include +#include +#include struct gpiomtd { void __iomem *io_sync; @@ -171,6 +174,96 @@ static int gpio_nand_devready(struct mtd_info *mtd) return gpio_get_value(gpiomtd->plat.gpio_rdy); } +#ifdef CONFIG_OF +static const struct of_device_id gpio_nand_id_table[] = { + { .compatible = "gpio-control-nand" }, + {} +}; +MODULE_DEVICE_TABLE(of, gpio_nand_id_table); + +static int gpio_nand_get_config_of(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + u32 val; + + if (!of_property_read_u32(dev->of_node, "bank-width", &val)) { + if (val == 2) { + plat->options |= NAND_BUSWIDTH_16; + } else if (val != 1) { + dev_err(dev, "invalid bank-width %u\n", val); + return -EINVAL; + } + } + + plat->gpio_rdy = of_get_gpio(dev->of_node, 0); + plat->gpio_nce = of_get_gpio(dev->of_node, 1); + plat->gpio_ale = of_get_gpio(dev->of_node, 2); + plat->gpio_cle = of_get_gpio(dev->of_node, 3); + plat->gpio_nwp = of_get_gpio(dev->of_node, 4); + + if (!of_property_read_u32(dev->of_node, "chip-delay", &val)) + plat->chip_delay = val; + + return 0; +} + +static struct resource *gpio_nand_get_io_sync_of(struct platform_device *pdev) +{ + struct resource *r = devm_kzalloc(&pdev->dev, sizeof(*r), GFP_KERNEL); + u64 addr; + + if (!r || of_property_read_u64(pdev->dev.of_node, + "gpio-control-nand,io-sync-reg", &addr)) + return NULL; + + r->start = addr; + r->end = r->start + 0x3; + r->flags = IORESOURCE_MEM; + + return r; +} +#else /* CONFIG_OF */ +#define gpio_nand_id_table NULL +static inline int gpio_nand_get_config_of(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + return -ENOSYS; +} + +static inline struct resource * +gpio_nand_get_io_sync_of(struct platform_device *pdev) +{ + return NULL +} +#endif /* CONFIG_OF */ + +static inline int gpio_nand_get_config(const struct device *dev, + struct gpio_nand_platdata *plat) +{ + int ret = gpio_nand_get_config_of(dev, plat); + + if (!ret) + return ret; + + if (dev->platform_data) { + memcpy(plat, dev->platform_data, sizeof(*plat)); + return 0; + } + + return -EINVAL; +} + +static inline struct resource * +gpio_nand_get_io_sync(struct platform_device *pdev) +{ + struct resource *r = gpio_nand_get_io_sync_of(pdev); + + if (r) + return r; + + return platform_get_resource(pdev, IORESOURCE_MEM, 1); +} + static int __devexit gpio_nand_remove(struct platform_device *dev) { struct gpiomtd *gpiomtd = platform_get_drvdata(dev); @@ -178,7 +271,7 @@ static int __devexit gpio_nand_remove(struct platform_device *dev) nand_release(&gpiomtd->mtd_info); - res = platform_get_resource(dev, IORESOURCE_MEM, 1); + res = gpio_nand_get_io_sync(dev); iounmap(gpiomtd->io_sync); if (res) release_mem_region(res->start, resource_size(res)); @@ -226,9 +319,10 @@ static int __devinit gpio_nand_probe(struct platform_device *dev) struct gpiomtd *gpiomtd; struct nand_chip *this; struct resource *res0, *res1; - int ret; + struct mtd_part_parser_data ppdata = {}; + int ret = 0; - if (!dev->dev.platform_data) + if (!dev->dev.of_node && !dev->dev.platform_data) return -EINVAL; res0 = platform_get_resource(dev, IORESOURCE_MEM, 0); @@ -248,7 +342,7 @@ static int __devinit gpio_nand_probe(struct platform_device *dev) goto err_map; } - res1 = platform_get_resource(dev, IORESOURCE_MEM, 1); + res1 = gpio_nand_get_io_sync(dev); if (res1) { gpiomtd->io_sync = request_and_remap(res1, 4, "NAND sync", &ret); if (!gpiomtd->io_sync) { @@ -257,7 +351,9 @@ static int __devinit gpio_nand_probe(struct platform_device *dev) } } - memcpy(&gpiomtd->plat, dev->dev.platform_data, sizeof(gpiomtd->plat)); + ret = gpio_nand_get_config(&dev->dev, &gpiomtd->plat); + if (ret) + goto err_nce; ret = gpio_request(gpiomtd->plat.gpio_nce, "NAND NCE"); if (ret) @@ -316,8 +412,12 @@ static int __devinit gpio_nand_probe(struct platform_device *dev) gpiomtd->plat.adjust_parts(&gpiomtd->plat, gpiomtd->mtd_info.size); - mtd_device_register(&gpiomtd->mtd_info, gpiomtd->plat.parts, - gpiomtd->plat.num_parts); + ppdata.of_node = dev->dev.of_node; + ret = mtd_device_parse_register(&gpiomtd->mtd_info, NULL, &ppdata, + gpiomtd->plat.parts, + gpiomtd->plat.num_parts); + if (ret) + goto err_wp; platform_set_drvdata(dev, gpiomtd); return 0; @@ -352,6 +452,7 @@ static struct platform_driver gpio_nand_driver = { .remove = gpio_nand_remove, .driver = { .name = "gpio-nand", + .of_match_table = gpio_nand_id_table, }, };