Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757436Ab2ENRnh (ORCPT ); Mon, 14 May 2012 13:43:37 -0400 Received: from nbd.name ([46.4.11.11]:55578 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757399Ab2ENRnf (ORCPT ); Mon, 14 May 2012 13:43:35 -0400 From: John Crispin To: Ralf Baechle Cc: linux-mips@linux-mips.org, John Crispin , Grant Likely , linux-kernel@vger.kernel.org Subject: [RESEND PATCH V2 09/17] GPIO: MIPS: lantiq: convert gpio-ebu to OF and move it to subsystem Date: Mon, 14 May 2012 19:42:35 +0200 Message-Id: <1337017363-14424-9-git-send-email-blogic@openwrt.org> X-Mailer: git-send-email 1.7.9.1 In-Reply-To: <1337017363-14424-1-git-send-email-blogic@openwrt.org> References: <1337017363-14424-1-git-send-email-blogic@openwrt.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10749 Lines: 366 Implements OF support and moves the driver from arch/mips/lantiq/xway/ to the gpio subsystem. By attaching hardware latches to the External Bus Unit (EBU) on Lantiq SoC, it is possible to create output only gpios. This driver configures a special memory address, which when written to, outputs 16 bit to the latches. This driver makes use of of_mm_gpio. Signed-off-by: John Crispin Cc: Grant Likely Cc: linux-kernel@vger.kernel.org --- This patch is part of a series moving the mips/lantiq target to OF and clkdev support. The patch, once Acked, should go upstream via Ralf's MIPS tree. arch/mips/lantiq/xway/Makefile | 2 +- arch/mips/lantiq/xway/gpio_ebu.c | 126 ------------------------------ drivers/gpio/Kconfig | 8 ++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-mm-lantiq.c | 157 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 167 insertions(+), 127 deletions(-) delete mode 100644 arch/mips/lantiq/xway/gpio_ebu.c create mode 100644 drivers/gpio/gpio-mm-lantiq.c diff --git a/arch/mips/lantiq/xway/Makefile b/arch/mips/lantiq/xway/Makefile index d0a0c96..dc3194f 100644 --- a/arch/mips/lantiq/xway/Makefile +++ b/arch/mips/lantiq/xway/Makefile @@ -1 +1 @@ -obj-y := prom.o sysctrl.o clk.o reset.o gpio.o gpio_ebu.o dma.o +obj-y := prom.o sysctrl.o clk.o reset.o gpio.o dma.o diff --git a/arch/mips/lantiq/xway/gpio_ebu.c b/arch/mips/lantiq/xway/gpio_ebu.c deleted file mode 100644 index b91c7f1..0000000 --- a/arch/mips/lantiq/xway/gpio_ebu.c +++ /dev/null @@ -1,126 +0,0 @@ -/* - * 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. - * - * Copyright (C) 2010 John Crispin - */ - -#include -#include -#include -#include -#include -#include -#include - -#include - -/* - * By attaching hardware latches to the EBU it is possible to create output - * only gpios. This driver configures a special memory address, which when - * written to outputs 16 bit to the latches. - */ - -#define LTQ_EBU_BUSCON 0x1e7ff /* 16 bit access, slowest timing */ -#define LTQ_EBU_WP 0x80000000 /* write protect bit */ - -/* we keep a shadow value of the last value written to the ebu */ -static int ltq_ebu_gpio_shadow = 0x0; -static void __iomem *ltq_ebu_gpio_membase; - -static void ltq_ebu_apply(void) -{ - unsigned long flags; - - spin_lock_irqsave(&ebu_lock, flags); - ltq_ebu_w32(LTQ_EBU_BUSCON, LTQ_EBU_BUSCON1); - *((__u16 *)ltq_ebu_gpio_membase) = ltq_ebu_gpio_shadow; - ltq_ebu_w32(LTQ_EBU_BUSCON | LTQ_EBU_WP, LTQ_EBU_BUSCON1); - spin_unlock_irqrestore(&ebu_lock, flags); -} - -static void ltq_ebu_set(struct gpio_chip *chip, unsigned offset, int value) -{ - if (value) - ltq_ebu_gpio_shadow |= (1 << offset); - else - ltq_ebu_gpio_shadow &= ~(1 << offset); - ltq_ebu_apply(); -} - -static int ltq_ebu_direction_output(struct gpio_chip *chip, unsigned offset, - int value) -{ - ltq_ebu_set(chip, offset, value); - - return 0; -} - -static struct gpio_chip ltq_ebu_chip = { - .label = "ltq_ebu", - .direction_output = ltq_ebu_direction_output, - .set = ltq_ebu_set, - .base = 72, - .ngpio = 16, - .can_sleep = 1, - .owner = THIS_MODULE, -}; - -static int ltq_ebu_probe(struct platform_device *pdev) -{ - int ret = 0; - struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - - if (!res) { - dev_err(&pdev->dev, "failed to get memory resource\n"); - return -ENOENT; - } - - res = devm_request_mem_region(&pdev->dev, res->start, - resource_size(res), dev_name(&pdev->dev)); - if (!res) { - dev_err(&pdev->dev, "failed to request memory resource\n"); - return -EBUSY; - } - - ltq_ebu_gpio_membase = devm_ioremap_nocache(&pdev->dev, res->start, - resource_size(res)); - if (!ltq_ebu_gpio_membase) { - dev_err(&pdev->dev, "Failed to ioremap mem region\n"); - return -ENOMEM; - } - - /* grab the default shadow value passed form the platform code */ - ltq_ebu_gpio_shadow = (unsigned int) pdev->dev.platform_data; - - /* tell the ebu controller which memory address we will be using */ - ltq_ebu_w32(pdev->resource->start | 0x1, LTQ_EBU_ADDRSEL1); - - /* write protect the region */ - ltq_ebu_w32(LTQ_EBU_BUSCON | LTQ_EBU_WP, LTQ_EBU_BUSCON1); - - ret = gpiochip_add(<q_ebu_chip); - if (!ret) - ltq_ebu_apply(); - return ret; -} - -static struct platform_driver ltq_ebu_driver = { - .probe = ltq_ebu_probe, - .driver = { - .name = "ltq_ebu", - .owner = THIS_MODULE, - }, -}; - -static int __init ltq_ebu_init(void) -{ - int ret = platform_driver_register(<q_ebu_driver); - - if (ret) - pr_info("ltq_ebu : Error registering platfom driver!"); - return ret; -} - -postcore_initcall(ltq_ebu_init); diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 4875071..8fae079 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -96,6 +96,14 @@ config GPIO_EP93XX depends on ARCH_EP93XX select GPIO_GENERIC +config GPIO_MM_LANTIQ + bool "Lantiq Memory mapped GPIOs" + depends on LANTIQ && SOC_XWAY + help + This enables support for memory mapped GPIOs on the External Bus Unit + (EBU) found on Lantiq SoCs. The gpios are output only as they are + created by attaching a 16bit latch to the bus. + config GPIO_MPC5200 def_bool y depends on PPC_MPC52xx diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 6447841..ed1c96d 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_GPIO_MC33880) += gpio-mc33880.o obj-$(CONFIG_GPIO_MC9S08DZ60) += gpio-mc9s08dz60.o obj-$(CONFIG_GPIO_MCP23S08) += gpio-mcp23s08.o obj-$(CONFIG_GPIO_ML_IOH) += gpio-ml-ioh.o +obj-$(CONFIG_GPIO_MM_LANTIQ) += gpio-mm-lantiq.o obj-$(CONFIG_GPIO_MPC5200) += gpio-mpc5200.o obj-$(CONFIG_GPIO_MPC8XXX) += gpio-mpc8xxx.o obj-$(CONFIG_GPIO_MSM_V1) += gpio-msm-v1.o diff --git a/drivers/gpio/gpio-mm-lantiq.c b/drivers/gpio/gpio-mm-lantiq.c new file mode 100644 index 0000000..9296801 --- /dev/null +++ b/drivers/gpio/gpio-mm-lantiq.c @@ -0,0 +1,157 @@ +/* + * 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. + * + * Copyright (C) 2012 John Crispin + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* + * By attaching hardware latches to the EBU it is possible to create output + * only gpios. This driver configures a special memory address, which when + * written to outputs 16 bit to the latches. + */ + +#define LTQ_EBU_BUSCON 0x1e7ff /* 16 bit access, slowest timing */ +#define LTQ_EBU_WP 0x80000000 /* write protect bit */ + +struct ltq_mm { + struct of_mm_gpio_chip mmchip; + u16 shadow; /* shadow the latches state */ +}; + +/* + * ltq_mm_apply - write the shadow value to the ebu address. + * @chip: Pointer to our private data structure. + * + * Write the shadow value to the EBU to set the gpios. We need to set the + * global EBU lock to make sure that PCI/MTD dont break. + */ +static void ltq_mm_apply(struct ltq_mm *chip) +{ + unsigned long flags; + + spin_lock_irqsave(&ebu_lock, flags); + ltq_ebu_w32(LTQ_EBU_BUSCON, LTQ_EBU_BUSCON1); + *((__u16 *)chip->mmchip.regs) = chip->shadow; + ltq_ebu_w32(LTQ_EBU_BUSCON | LTQ_EBU_WP, LTQ_EBU_BUSCON1); + spin_unlock_irqrestore(&ebu_lock, flags); +} + +/* + * ltq_mm_set - gpio_chip->set - set gpios. + * @gc: Pointer to gpio_chip device structure. + * @gpio: GPIO signal number. + * @val: Value to be written to specified signal. + * + * Set the shadow value and call ltq_mm_apply. + */ +static void ltq_mm_set(struct gpio_chip *gc, unsigned offset, int value) +{ + struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc); + struct ltq_mm *chip = + container_of(mm_gc, struct ltq_mm, mmchip); + + if (value) + chip->shadow |= (1 << offset); + else + chip->shadow &= ~(1 << offset); + ltq_mm_apply(chip); +} + +/* + * ltq_mm_dir_out - gpio_chip->dir_out - set gpio direction. + * @gc: Pointer to gpio_chip device structure. + * @gpio: GPIO signal number. + * @val: Value to be written to specified signal. + * + * Same as ltq_mm_set, always returns 0. + */ +static int ltq_mm_dir_out(struct gpio_chip *gc, unsigned offset, int value) +{ + ltq_mm_set(gc, offset, value); + + return 0; +} + +/* + * ltq_mm_save_regs - Set initial values of GPIO pins + * @mm_gc: pointer to memory mapped GPIO chip structure + */ +static void ltq_mm_save_regs(struct of_mm_gpio_chip *mm_gc) +{ + struct ltq_mm *chip = + container_of(mm_gc, struct ltq_mm, mmchip); + + /* tell the ebu controller which memory address we will be using */ + ltq_ebu_w32(CPHYSADDR(chip->mmchip.regs) | 0x1, LTQ_EBU_ADDRSEL1); + + ltq_mm_apply(chip); +} + +static int ltq_mm_probe(struct platform_device *pdev) +{ + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + struct ltq_mm *chip; + const __be32 *shadow; + int ret = 0; + + if (!res) { + dev_err(&pdev->dev, "failed to get memory resource\n"); + return -ENOENT; + } + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->mmchip.gc.ngpio = 16; + chip->mmchip.gc.label = "gpio-mm-ltq"; + chip->mmchip.gc.direction_output = ltq_mm_dir_out; + chip->mmchip.gc.set = ltq_mm_set; + chip->mmchip.save_regs = ltq_mm_save_regs; + + /* store the shadow value if one was passed by the devicetree */ + shadow = of_get_property(pdev->dev.of_node, "lantiq,shadow", NULL); + if (shadow) + chip->shadow = *shadow; + + ret = of_mm_gpiochip_add(pdev->dev.of_node, &chip->mmchip); + if (ret) + kfree(chip); + return ret; +} + +static const struct of_device_id ltq_mm_match[] = { + { .compatible = "lantiq,gpio-mm" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ltq_mm_match); + +static struct platform_driver ltq_mm_driver = { + .probe = ltq_mm_probe, + .driver = { + .name = "gpio-mm-ltq", + .owner = THIS_MODULE, + .of_match_table = ltq_mm_match, + }, +}; + +static int __init ltq_mm_init(void) +{ + return platform_driver_register(<q_mm_driver); +} + +subsys_initcall(ltq_mm_init); -- 1.7.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/