Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S945107AbcJSPau (ORCPT ); Wed, 19 Oct 2016 11:30:50 -0400 Received: from mail-lf0-f45.google.com ([209.85.215.45]:34127 "EHLO mail-lf0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S942974AbcJSPar (ORCPT ); Wed, 19 Oct 2016 11:30:47 -0400 Subject: Re: [PATCH] mtd: nand: Add OX820 NAND Support To: dwmw2@infradead.org, computersforpeace@gmail.com, boris.brezillon@free-electrons.com, richard@nod.at References: <20161019145523.6763-1-narmstrong@baylibre.com> Cc: linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-oxnas@lists.tuxfamily.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, daniel@makrotopia.org From: Neil Armstrong Organization: Baylibre Message-ID: <12212beb-d152-9b49-3c06-227956e84207@baylibre.com> Date: Wed, 19 Oct 2016 17:30:38 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <20161019145523.6763-1-narmstrong@baylibre.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9035 Lines: 298 On 10/19/2016 04:55 PM, Neil Armstrong wrote: > Add NAND driver to support the Oxford Semiconductor OX820 NAND Controller. > This is a simple memory mapped NAND controller with single chip select and > software ECC. > > Signed-off-by: Neil Armstrong Forgot Acked-by: Rob Herring Will add in v2 if a respin is needed. > --- > .../devicetree/bindings/mtd/oxnas-nand.txt | 24 +++ > drivers/mtd/nand/Kconfig | 5 + > drivers/mtd/nand/Makefile | 1 + > drivers/mtd/nand/oxnas_nand.c | 204 +++++++++++++++++++++ > 4 files changed, 234 insertions(+) > create mode 100644 Documentation/devicetree/bindings/mtd/oxnas-nand.txt > create mode 100644 drivers/mtd/nand/oxnas_nand.c > > Changes since RFC http://lkml.kernel.org/r/20161018090927.1990-1-narmstrong@baylibre.com : > - Avoid using chip->IO_ADDR* > - Use new DT structure > - Assign a chip for the subnode > - Use the nand_hw_control structure > - Cleanup probe > - Cleanup cmd_ctrl by using a context ctrl offset used in write_bytes > > diff --git a/Documentation/devicetree/bindings/mtd/oxnas-nand.txt b/Documentation/devicetree/bindings/mtd/oxnas-nand.txt > new file mode 100644 > index 0000000..83b684d > --- /dev/null > +++ b/Documentation/devicetree/bindings/mtd/oxnas-nand.txt > @@ -0,0 +1,24 @@ > +* Oxford Semiconductor OXNAS NAND Controller > + > +Please refer to nand.txt for generic information regarding MTD NAND bindings. > + > +Required properties: > + - compatible: "oxsemi,ox820-nand" > + - reg: Base address and length for NAND mapped memory. > + > +Optional Properties: > + - clocks: phandle to the NAND gate clock if needed. > + - resets: phandle to the NAND reset control if needed. > + > +Example: > + > +nand: nand@41000000 { > + compatible = "oxsemi,ox820-nand"; > + reg = <0x41000000 0x100000>; > + nand-ecc-mode = "soft"; > + clocks = <&stdclk CLK_820_NAND>; > + resets = <&reset RESET_NAND>; > + #address-cells = <1>; > + #size-cells = <1>; > + status = "disabled"; > +}; > diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig > index 7b7a887..c023125 100644 > --- a/drivers/mtd/nand/Kconfig > +++ b/drivers/mtd/nand/Kconfig > @@ -426,6 +426,11 @@ config MTD_NAND_ORION > No board specific support is done by this driver, each board > must advertise a platform_device for the driver to attach. > > +config MTD_NAND_OXNAS > + tristate "NAND Flash support for Oxford Semiconductor SoC" > + help > + This enables the NAND flash controller on Oxford Semiconductor SoCs. > + > config MTD_NAND_FSL_ELBC > tristate "NAND support for Freescale eLBC controllers" > depends on FSL_SOC > diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile > index cafde6f..05fc054 100644 > --- a/drivers/mtd/nand/Makefile > +++ b/drivers/mtd/nand/Makefile > @@ -35,6 +35,7 @@ obj-$(CONFIG_MTD_NAND_TMIO) += tmio_nand.o > obj-$(CONFIG_MTD_NAND_PLATFORM) += plat_nand.o > obj-$(CONFIG_MTD_NAND_PASEMI) += pasemi_nand.o > obj-$(CONFIG_MTD_NAND_ORION) += orion_nand.o > +obj-$(CONFIG_MTD_NAND_OXNAS) += oxnas_nand.o > obj-$(CONFIG_MTD_NAND_FSL_ELBC) += fsl_elbc_nand.o > obj-$(CONFIG_MTD_NAND_FSL_IFC) += fsl_ifc_nand.o > obj-$(CONFIG_MTD_NAND_FSL_UPM) += fsl_upm.o > diff --git a/drivers/mtd/nand/oxnas_nand.c b/drivers/mtd/nand/oxnas_nand.c > new file mode 100644 > index 0000000..a9fe1ac > --- /dev/null > +++ b/drivers/mtd/nand/oxnas_nand.c > @@ -0,0 +1,204 @@ > +/* > + * Oxford Semiconductor OXNAS NAND driver > + > + * Copyright (C) 2016 Neil Armstrong > + * Heavily based on plat_nand.c : > + * Author: Vitaly Wool > + * Copyright (C) 2013 Ma Haijun > + * Copyright (C) 2012 John Crispin > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Nand commands */ > +#define OXNAS_NAND_CMD_ALE BIT(18) > +#define OXNAS_NAND_CMD_CLE BIT(19) > + > +#define OXNAS_NAND_MAX_CHIPS 1 > + > +struct oxnas_nand { > + struct nand_hw_control base; > + void __iomem *io_base; > + struct clk *clk; > + struct nand_chip *chips[OXNAS_NAND_MAX_CHIPS]; > + unsigned long ctrl; > +}; > + > +static uint8_t oxnas_nand_read_byte(struct mtd_info *mtd) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + struct oxnas_nand *oxnas = nand_get_controller_data(chip); > + > + return readb(oxnas->io_base); > +} > + > +static void oxnas_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + struct oxnas_nand *oxnas = nand_get_controller_data(chip); > + > + ioread8_rep(oxnas->io_base, buf, len); > +} > + > +static void oxnas_nand_write_buf(struct mtd_info *mtd, > + const uint8_t *buf, int len) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + struct oxnas_nand *oxnas = nand_get_controller_data(chip); > + > + iowrite8_rep(oxnas->io_base + oxnas->ctrl, buf, len); > +} > + > +/* Single CS command control */ > +static void oxnas_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, > + unsigned int ctrl) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + struct oxnas_nand *oxnas = nand_get_controller_data(chip); > + > + if (ctrl & NAND_CTRL_CHANGE) { > + if (ctrl & NAND_CLE) > + oxnas->ctrl = OXNAS_NAND_CMD_CLE; > + else if (ctrl & NAND_ALE) > + oxnas->ctrl = OXNAS_NAND_CMD_ALE; > + else > + oxnas->ctrl = 0; > + } > + > + if (cmd != NAND_CMD_NONE) > + writeb(cmd, oxnas->io_base + oxnas->ctrl); > +} > + > +/* > + * Probe for the NAND device. > + */ > +static int oxnas_nand_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct device_node *nand_np; > + struct oxnas_nand *oxnas; > + struct nand_chip *chip; > + struct mtd_info *mtd; > + struct resource *res; > + int nchips = 0; > + int count = 0; > + int err = 0; > + > + /* Allocate memory for the device structure (and zero it) */ > + oxnas = devm_kzalloc(&pdev->dev, sizeof(struct nand_chip), > + GFP_KERNEL); > + if (!oxnas) > + return -ENOMEM; > + > + nand_hw_control_init(&oxnas->base); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + oxnas->io_base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(oxnas->io_base)) > + return PTR_ERR(oxnas->io_base); > + > + oxnas->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(oxnas->clk)) > + oxnas->clk = NULL; > + > + /* Only a single chip node is supported */ > + count = of_get_child_count(np); > + if (count > 1) > + return -EINVAL; > + > + clk_prepare_enable(oxnas->clk); > + device_reset_optional(&pdev->dev); > + > + for_each_child_of_node(np, nand_np) { > + chip = devm_kzalloc(&pdev->dev, sizeof(struct nand_chip), > + GFP_KERNEL); > + if (!chip) > + return -ENOMEM; > + > + chip->controller = &oxnas->base; > + > + nand_set_flash_node(chip, nand_np); > + nand_set_controller_data(chip, oxnas); > + > + mtd = nand_to_mtd(chip); > + mtd->dev.parent = &pdev->dev; > + mtd->priv = chip; > + > + chip->cmd_ctrl = oxnas_nand_cmd_ctrl; > + chip->read_buf = oxnas_nand_read_buf; > + chip->read_byte = oxnas_nand_read_byte; > + chip->write_buf = oxnas_nand_write_buf; > + chip->chip_delay = 30; > + > + /* Scan to find existence of the device */ > + err = nand_scan(mtd, 1); > + if (err) > + return err; > + > + err = mtd_device_register(mtd, NULL, 0); > + if (err) { > + nand_release(mtd); > + return err; > + } > + > + oxnas->chips[nchips] = chip; > + ++nchips; > + } > + > + /* Exit if no chips found */ > + if (!nchips) > + return -ENODEV; > + > + platform_set_drvdata(pdev, oxnas); > + > + return 0; > +} > + > +static int oxnas_nand_remove(struct platform_device *pdev) > +{ > + struct oxnas_nand *oxnas = platform_get_drvdata(pdev); > + > + if (oxnas->chips[0]) > + nand_release(nand_to_mtd(oxnas->chips[0])); > + > + clk_disable_unprepare(oxnas->clk); > + > + return 0; > +} > + > +static const struct of_device_id oxnas_nand_match[] = { > + { .compatible = "oxsemi,ox820-nand" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, oxnas_nand_match); > + > +static struct platform_driver oxnas_nand_driver = { > + .probe = oxnas_nand_probe, > + .remove = oxnas_nand_remove, > + .driver = { > + .name = "oxnas_nand", > + .of_match_table = oxnas_nand_match, > + }, > +}; > + > +module_platform_driver(oxnas_nand_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Neil Armstrong "); > +MODULE_DESCRIPTION("Oxnas NAND driver"); > +MODULE_ALIAS("platform:oxnas_nand"); >