[linux-block.git] / drivers / gpio / gpio-amdpt.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Promontory GPIO driver
 *
 * Copyright (C) 2015 ASMedia Technology Inc.
 * Author: YD Tseng <yd_tseng@asmedia.com.tw>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio/driver.h>
#include <linux/spinlock.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>

#define PT_TOTAL_GPIO 8
#define PT_TOTAL_GPIO_EX 24

/* PCI-E MMIO register offsets */
#define PT_DIRECTION_REG   0x00
#define PT_INPUTDATA_REG   0x04
#define PT_OUTPUTDATA_REG  0x08
#define PT_CLOCKRATE_REG   0x0C
#define PT_SYNC_REG        0x28

struct pt_gpio_chip {
	struct gpio_chip         gc;
	void __iomem             *reg_base;
};

static int pt_gpio_request(struct gpio_chip *gc, unsigned offset)
{
	struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
	unsigned long flags;
	u32 using_pins;

	dev_dbg(gc->parent, "pt_gpio_request offset=%x\n", offset);

	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);

	using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
	if (using_pins & BIT(offset)) {
		dev_warn(gc->parent, "PT GPIO pin %x reconfigured\n",
			 offset);
		raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
		return -EINVAL;
	}

	writel(using_pins | BIT(offset), pt_gpio->reg_base + PT_SYNC_REG);

	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);

	return 0;
}

static void pt_gpio_free(struct gpio_chip *gc, unsigned offset)
{
	struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
	unsigned long flags;
	u32 using_pins;

	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);

	using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
	using_pins &= ~BIT(offset);
	writel(using_pins, pt_gpio->reg_base + PT_SYNC_REG);

	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);

	dev_dbg(gc->parent, "pt_gpio_free offset=%x\n", offset);
}

static int pt_gpio_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct pt_gpio_chip *pt_gpio;
	int ret = 0;

	if (!ACPI_COMPANION(dev)) {
		dev_err(dev, "PT GPIO device node not found\n");
		return -ENODEV;
	}

	pt_gpio = devm_kzalloc(dev, sizeof(struct pt_gpio_chip), GFP_KERNEL);
	if (!pt_gpio)
		return -ENOMEM;

	pt_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(pt_gpio->reg_base)) {
		dev_err(dev, "Failed to map MMIO resource for PT GPIO.\n");
		return PTR_ERR(pt_gpio->reg_base);
	}

	ret = bgpio_init(&pt_gpio->gc, dev, 4,
			 pt_gpio->reg_base + PT_INPUTDATA_REG,
			 pt_gpio->reg_base + PT_OUTPUTDATA_REG, NULL,
			 pt_gpio->reg_base + PT_DIRECTION_REG, NULL,
			 BGPIOF_READ_OUTPUT_REG_SET);
	if (ret) {
		dev_err(dev, "bgpio_init failed\n");
		return ret;
	}

	pt_gpio->gc.owner            = THIS_MODULE;
	pt_gpio->gc.request          = pt_gpio_request;
	pt_gpio->gc.free             = pt_gpio_free;
	pt_gpio->gc.ngpio            = (uintptr_t)device_get_match_data(dev);

	ret = gpiochip_add_data(&pt_gpio->gc, pt_gpio);
	if (ret) {
		dev_err(dev, "Failed to register GPIO lib\n");
		return ret;
	}

	platform_set_drvdata(pdev, pt_gpio);

	/* initialize register setting */
	writel(0, pt_gpio->reg_base + PT_SYNC_REG);
	writel(0, pt_gpio->reg_base + PT_CLOCKRATE_REG);

	dev_dbg(dev, "PT GPIO driver loaded\n");
	return ret;
}

static int pt_gpio_remove(struct platform_device *pdev)
{
	struct pt_gpio_chip *pt_gpio = platform_get_drvdata(pdev);

	gpiochip_remove(&pt_gpio->gc);

	return 0;
}

static const struct acpi_device_id pt_gpio_acpi_match[] = {
	{ "AMDF030", PT_TOTAL_GPIO },
	{ "AMDIF030", PT_TOTAL_GPIO },
	{ "AMDIF031", PT_TOTAL_GPIO_EX },
	{ },
};
MODULE_DEVICE_TABLE(acpi, pt_gpio_acpi_match);

static struct platform_driver pt_gpio_driver = {
	.driver = {
		.name = "pt-gpio",
		.acpi_match_table = ACPI_PTR(pt_gpio_acpi_match),
	},
	.probe = pt_gpio_probe,
	.remove = pt_gpio_remove,
};

module_platform_driver(pt_gpio_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("YD Tseng <yd_tseng@asmedia.com.tw>");
MODULE_DESCRIPTION("AMD Promontory GPIO Driver");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
6057d40f YT	2	/*
	3	* AMD Promontory GPIO driver
	4	*
	5	* Copyright (C) 2015 ASMedia Technology Inc.
	6	* Author: YD Tseng <yd_tseng@asmedia.com.tw>
6057d40f YT	7	*/
	8
	9	#include <linux/kernel.h>
	10	#include <linux/module.h>
	11	#include <linux/gpio/driver.h>
	12	#include <linux/spinlock.h>
	13	#include <linux/acpi.h>
	14	#include <linux/platform_device.h>
	15
	16	#define PT_TOTAL_GPIO 8
2ac5eb84	17	#define PT_TOTAL_GPIO_EX 24
6057d40f YT	18
	19	/* PCI-E MMIO register offsets */
	20	#define PT_DIRECTION_REG 0x00
	21	#define PT_INPUTDATA_REG 0x04
	22	#define PT_OUTPUTDATA_REG 0x08
	23	#define PT_CLOCKRATE_REG 0x0C
	24	#define PT_SYNC_REG 0x28
	25
	26	struct pt_gpio_chip {
	27	struct gpio_chip gc;
	28	void __iomem *reg_base;
6057d40f YT	29	};
6057d40f YT	30
6057d40f YT	31	static int pt_gpio_request(struct gpio_chip *gc, unsigned offset)
6057d40f YT	32	{
fb722887	33	struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
6057d40f YT	34	unsigned long flags;
	35	u32 using_pins;
	36
58383c78	37	dev_dbg(gc->parent, "pt_gpio_request offset=%x\n", offset);
6057d40f	38
3c938cc5	39	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
6057d40f YT	40
	41	using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
	42	if (using_pins & BIT(offset)) {
58383c78 LW	43	dev_warn(gc->parent, "PT GPIO pin %x reconfigured\n",
58383c78 LW	44	offset);
3c938cc5	45	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
6057d40f YT	46	return -EINVAL;
	47	}
	48
	49	writel(using_pins \| BIT(offset), pt_gpio->reg_base + PT_SYNC_REG);
	50
3c938cc5	51	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
6057d40f YT	52
	53	return 0;
	54	}
	55
	56	static void pt_gpio_free(struct gpio_chip *gc, unsigned offset)
	57	{
fb722887	58	struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc);
6057d40f YT	59	unsigned long flags;
	60	u32 using_pins;
	61
3c938cc5	62	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
6057d40f YT	63
	64	using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG);
	65	using_pins &= ~BIT(offset);
	66	writel(using_pins, pt_gpio->reg_base + PT_SYNC_REG);
	67
3c938cc5	68	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
6057d40f	69
58383c78	70	dev_dbg(gc->parent, "pt_gpio_free offset=%x\n", offset);
6057d40f YT	71	}
6057d40f YT	72
6057d40f YT	73	static int pt_gpio_probe(struct platform_device *pdev)
	74	{
	75	struct device *dev = &pdev->dev;
6057d40f	76	struct pt_gpio_chip *pt_gpio;
6057d40f YT	77	int ret = 0;
6057d40f YT	78
f0b2731b	79	if (!ACPI_COMPANION(dev)) {
6057d40f YT	80	dev_err(dev, "PT GPIO device node not found\n");
	81	return -ENODEV;
	82	}
	83
	84	pt_gpio = devm_kzalloc(dev, sizeof(struct pt_gpio_chip), GFP_KERNEL);
	85	if (!pt_gpio)
	86	return -ENOMEM;
	87
bb17a27a	88	pt_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0);
6057d40f	89	if (IS_ERR(pt_gpio->reg_base)) {
2b3fee36	90	dev_err(dev, "Failed to map MMIO resource for PT GPIO.\n");
6057d40f YT	91	return PTR_ERR(pt_gpio->reg_base);
	92	}
	93
574b782e AL	94	ret = bgpio_init(&pt_gpio->gc, dev, 4,
	95	pt_gpio->reg_base + PT_INPUTDATA_REG,
	96	pt_gpio->reg_base + PT_OUTPUTDATA_REG, NULL,
	97	pt_gpio->reg_base + PT_DIRECTION_REG, NULL,
	98	BGPIOF_READ_OUTPUT_REG_SET);
	99	if (ret) {
2b3fee36	100	dev_err(dev, "bgpio_init failed\n");
574b782e AL	101	return ret;
574b782e AL	102	}
6057d40f	103
6057d40f	104	pt_gpio->gc.owner = THIS_MODULE;
6057d40f YT	105	pt_gpio->gc.request = pt_gpio_request;
6057d40f YT	106	pt_gpio->gc.free = pt_gpio_free;
2ac5eb84	107	pt_gpio->gc.ngpio = (uintptr_t)device_get_match_data(dev);
448cf905	108
fb722887	109	ret = gpiochip_add_data(&pt_gpio->gc, pt_gpio);
6057d40f	110	if (ret) {
2b3fee36	111	dev_err(dev, "Failed to register GPIO lib\n");
6057d40f YT	112	return ret;
	113	}
	114
	115	platform_set_drvdata(pdev, pt_gpio);
	116
	117	/* initialize register setting */
	118	writel(0, pt_gpio->reg_base + PT_SYNC_REG);
	119	writel(0, pt_gpio->reg_base + PT_CLOCKRATE_REG);
	120
2b3fee36	121	dev_dbg(dev, "PT GPIO driver loaded\n");
6057d40f YT	122	return ret;
	123	}
	124
	125	static int pt_gpio_remove(struct platform_device *pdev)
	126	{
	127	struct pt_gpio_chip *pt_gpio = platform_get_drvdata(pdev);
	128
	129	gpiochip_remove(&pt_gpio->gc);
	130
	131	return 0;
	132	}
	133
	134	static const struct acpi_device_id pt_gpio_acpi_match[] = {
2ac5eb84 HY	135	{ "AMDF030", PT_TOTAL_GPIO },
	136	{ "AMDIF030", PT_TOTAL_GPIO },
	137	{ "AMDIF031", PT_TOTAL_GPIO_EX },
6057d40f YT	138	{ },
	139	};
	140	MODULE_DEVICE_TABLE(acpi, pt_gpio_acpi_match);
	141
	142	static struct platform_driver pt_gpio_driver = {
	143	.driver = {
	144	.name = "pt-gpio",
	145	.acpi_match_table = ACPI_PTR(pt_gpio_acpi_match),
	146	},
	147	.probe = pt_gpio_probe,
	148	.remove = pt_gpio_remove,
	149	};
	150
	151	module_platform_driver(pt_gpio_driver);
	152
	153	MODULE_LICENSE("GPL");
	154	MODULE_AUTHOR("YD Tseng <yd_tseng@asmedia.com.tw>");
	155	MODULE_DESCRIPTION("AMD Promontory GPIO Driver");