[linux-2.6-block.git] / drivers / gpio / gpio-hlwd.c

// SPDX-License-Identifier: GPL-2.0+
// Copyright (C) 2008-2009 The GameCube Linux Team
// Copyright (C) 2008,2009 Albert Herranz
// Copyright (C) 2017-2018 Jonathan Neuschäfer
//
// Nintendo Wii (Hollywood) GPIO driver

#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/slab.h>

/*
 * Register names and offsets courtesy of WiiBrew:
 * https://wiibrew.org/wiki/Hardware/Hollywood_GPIOs
 *
 * Note that for most registers, there are two versions:
 * - HW_GPIOB_* Is always accessible by the Broadway PowerPC core, but does
 *   always give access to all GPIO lines
 * - HW_GPIO_* Is only accessible by the Broadway PowerPC code if the memory
 *   firewall (AHBPROT) in the Hollywood chipset has been configured to allow
 *   such access.
 *
 * The ownership of each GPIO line can be configured in the HW_GPIO_OWNER
 * register: A one bit configures the line for access via the HW_GPIOB_*
 * registers, a zero bit indicates access via HW_GPIO_*. This driver uses
 * HW_GPIOB_*.
 */
#define HW_GPIOB_OUT		0x00
#define HW_GPIOB_DIR		0x04
#define HW_GPIOB_IN		0x08
#define HW_GPIOB_INTLVL		0x0c
#define HW_GPIOB_INTFLAG	0x10
#define HW_GPIOB_INTMASK	0x14
#define HW_GPIOB_INMIR		0x18
#define HW_GPIO_ENABLE		0x1c
#define HW_GPIO_OUT		0x20
#define HW_GPIO_DIR		0x24
#define HW_GPIO_IN		0x28
#define HW_GPIO_INTLVL		0x2c
#define HW_GPIO_INTFLAG		0x30
#define HW_GPIO_INTMASK		0x34
#define HW_GPIO_INMIR		0x38
#define HW_GPIO_OWNER		0x3c

struct hlwd_gpio {
	struct gpio_chip gpioc;
	void __iomem *regs;
};

static int hlwd_gpio_probe(struct platform_device *pdev)
{
	struct hlwd_gpio *hlwd;
	struct resource *regs_resource;
	u32 ngpios;
	int res;

	hlwd = devm_kzalloc(&pdev->dev, sizeof(*hlwd), GFP_KERNEL);
	if (!hlwd)
		return -ENOMEM;

	regs_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	hlwd->regs = devm_ioremap_resource(&pdev->dev, regs_resource);
	if (IS_ERR(hlwd->regs))
		return PTR_ERR(hlwd->regs);

	/*
	 * Claim all GPIOs using the OWNER register. This will not work on
	 * systems where the AHBPROT memory firewall hasn't been configured to
	 * permit PPC access to HW_GPIO_*.
	 *
	 * Note that this has to happen before bgpio_init reads the
	 * HW_GPIOB_OUT and HW_GPIOB_DIR, because otherwise it reads the wrong
	 * values.
	 */
	iowrite32be(0xffffffff, hlwd->regs + HW_GPIO_OWNER);

	res = bgpio_init(&hlwd->gpioc, &pdev->dev, 4,
			hlwd->regs + HW_GPIOB_IN, hlwd->regs + HW_GPIOB_OUT,
			NULL, hlwd->regs + HW_GPIOB_DIR, NULL,
			BGPIOF_BIG_ENDIAN_BYTE_ORDER);
	if (res < 0) {
		dev_warn(&pdev->dev, "bgpio_init failed: %d\n", res);
		return res;
	}

	res = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios);
	if (res)
		ngpios = 32;
	hlwd->gpioc.ngpio = ngpios;

	return devm_gpiochip_add_data(&pdev->dev, &hlwd->gpioc, hlwd);
}

static const struct of_device_id hlwd_gpio_match[] = {
	{ .compatible = "nintendo,hollywood-gpio", },
	{},
};
MODULE_DEVICE_TABLE(of, hlwd_gpio_match);

static struct platform_driver hlwd_gpio_driver = {
	.driver	= {
		.name		= "gpio-hlwd",
		.of_match_table	= hlwd_gpio_match,
	},
	.probe	= hlwd_gpio_probe,
};
module_platform_driver(hlwd_gpio_driver);

MODULE_AUTHOR("Jonathan Neuschäfer <j.neuschaefer@gmx.net>");
MODULE_DESCRIPTION("Nintendo Wii GPIO driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
8f55fed3 JN	1	// SPDX-License-Identifier: GPL-2.0+
	2	// Copyright (C) 2008-2009 The GameCube Linux Team
	3	// Copyright (C) 2008,2009 Albert Herranz
	4	// Copyright (C) 2017-2018 Jonathan Neuschäfer
	5	//
	6	// Nintendo Wii (Hollywood) GPIO driver
	7
	8	#include <linux/gpio/driver.h>
	9	#include <linux/io.h>
	10	#include <linux/kernel.h>
	11	#include <linux/module.h>
	12	#include <linux/of.h>
	13	#include <linux/of_platform.h>
	14	#include <linux/slab.h>
	15
	16	/*
	17	* Register names and offsets courtesy of WiiBrew:
	18	* https://wiibrew.org/wiki/Hardware/Hollywood_GPIOs
	19	*
	20	* Note that for most registers, there are two versions:
	21	* - HW_GPIOB_* Is always accessible by the Broadway PowerPC core, but does
	22	* always give access to all GPIO lines
	23	* - HW_GPIO_* Is only accessible by the Broadway PowerPC code if the memory
	24	* firewall (AHBPROT) in the Hollywood chipset has been configured to allow
	25	* such access.
	26	*
	27	* The ownership of each GPIO line can be configured in the HW_GPIO_OWNER
	28	* register: A one bit configures the line for access via the HW_GPIOB_*
	29	* registers, a zero bit indicates access via HW_GPIO_*. This driver uses
	30	* HW_GPIOB_*.
	31	*/
	32	#define HW_GPIOB_OUT 0x00
	33	#define HW_GPIOB_DIR 0x04
	34	#define HW_GPIOB_IN 0x08
	35	#define HW_GPIOB_INTLVL 0x0c
	36	#define HW_GPIOB_INTFLAG 0x10
	37	#define HW_GPIOB_INTMASK 0x14
	38	#define HW_GPIOB_INMIR 0x18
	39	#define HW_GPIO_ENABLE 0x1c
	40	#define HW_GPIO_OUT 0x20
	41	#define HW_GPIO_DIR 0x24
	42	#define HW_GPIO_IN 0x28
	43	#define HW_GPIO_INTLVL 0x2c
	44	#define HW_GPIO_INTFLAG 0x30
	45	#define HW_GPIO_INTMASK 0x34
	46	#define HW_GPIO_INMIR 0x38
	47	#define HW_GPIO_OWNER 0x3c
	48
	49	struct hlwd_gpio {
	50	struct gpio_chip gpioc;
	51	void __iomem *regs;
	52	};
	53
	54	static int hlwd_gpio_probe(struct platform_device *pdev)
	55	{
	56	struct hlwd_gpio *hlwd;
	57	struct resource *regs_resource;
	58	u32 ngpios;
	59	int res;
	60
	61	hlwd = devm_kzalloc(&pdev->dev, sizeof(*hlwd), GFP_KERNEL);
	62	if (!hlwd)
	63	return -ENOMEM;
	64
65	regs_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
66	hlwd->regs = devm_ioremap_resource(&pdev->dev, regs_resource);
67	if (IS_ERR(hlwd->regs))
68	return PTR_ERR(hlwd->regs);
69
70	/*
71	* Claim all GPIOs using the OWNER register. This will not work on
72	* systems where the AHBPROT memory firewall hasn't been configured to
73	* permit PPC access to HW_GPIO_*.
74	*
75	* Note that this has to happen before bgpio_init reads the
76	* HW_GPIOB_OUT and HW_GPIOB_DIR, because otherwise it reads the wrong
77	* values.
78	*/
79	iowrite32be(0xffffffff, hlwd->regs + HW_GPIO_OWNER);
80
81	res = bgpio_init(&hlwd->gpioc, &pdev->dev, 4,
82	hlwd->regs + HW_GPIOB_IN, hlwd->regs + HW_GPIOB_OUT,
83	NULL, hlwd->regs + HW_GPIOB_DIR, NULL,
84	BGPIOF_BIG_ENDIAN_BYTE_ORDER);
85	if (res < 0) {
86	dev_warn(&pdev->dev, "bgpio_init failed: %d\n", res);
87	return res;
88	}
89
90	res = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios);
91	if (res)
92	ngpios = 32;
93	hlwd->gpioc.ngpio = ngpios;
94
95	return devm_gpiochip_add_data(&pdev->dev, &hlwd->gpioc, hlwd);
96	}
97
98	static const struct of_device_id hlwd_gpio_match[] = {
99	{ .compatible = "nintendo,hollywood-gpio", },
100	{},
101	};
102	MODULE_DEVICE_TABLE(of, hlwd_gpio_match);
103
104	static struct platform_driver hlwd_gpio_driver = {
105	.driver = {
106	.name = "gpio-hlwd",
107	.of_match_table = hlwd_gpio_match,
108	},
109	.probe = hlwd_gpio_probe,
110	};
111	module_platform_driver(hlwd_gpio_driver);
112
113	MODULE_AUTHOR("Jonathan Neuschäfer <j.neuschaefer@gmx.net>");
114	MODULE_DESCRIPTION("Nintendo Wii GPIO driver");
115	MODULE_LICENSE("GPL");