[linux-2.6-block.git] / drivers / gpio / gpio-mlxbf2.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/acpi.h>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/resource.h>
#include <linux/spinlock.h>
#include <linux/types.h>

/*
 * There are 3 YU GPIO blocks:
 * gpio[0]: HOST_GPIO0->HOST_GPIO31
 * gpio[1]: HOST_GPIO32->HOST_GPIO63
 * gpio[2]: HOST_GPIO64->HOST_GPIO69
 */
#define MLXBF2_GPIO_MAX_PINS_PER_BLOCK 32

/*
 * arm_gpio_lock register:
 * bit[31]	lock status: active if set
 * bit[15:0]	set lock
 * The lock is enabled only if 0xd42f is written to this field
 */
#define YU_ARM_GPIO_LOCK_ADDR		0x2801088
#define YU_ARM_GPIO_LOCK_SIZE		0x8
#define YU_LOCK_ACTIVE_BIT(val)		(val >> 31)
#define YU_ARM_GPIO_LOCK_ACQUIRE	0xd42f
#define YU_ARM_GPIO_LOCK_RELEASE	0x0

/*
 * gpio[x] block registers and their offset
 */
#define YU_GPIO_DATAIN			0x04
#define YU_GPIO_MODE1			0x08
#define YU_GPIO_MODE0			0x0c
#define YU_GPIO_DATASET			0x14
#define YU_GPIO_DATACLEAR		0x18
#define YU_GPIO_MODE1_CLEAR		0x50
#define YU_GPIO_MODE0_SET		0x54
#define YU_GPIO_MODE0_CLEAR		0x58

#ifdef CONFIG_PM
struct mlxbf2_gpio_context_save_regs {
	u32 gpio_mode0;
	u32 gpio_mode1;
};
#endif

/* BlueField-2 gpio block context structure. */
struct mlxbf2_gpio_context {
	struct gpio_chip gc;

	/* YU GPIO blocks address */
	void __iomem *gpio_io;

#ifdef CONFIG_PM
	struct mlxbf2_gpio_context_save_regs *csave_regs;
#endif
};

/* BlueField-2 gpio shared structure. */
struct mlxbf2_gpio_param {
	void __iomem *io;
	struct resource *res;
	struct mutex *lock;
};

static struct resource yu_arm_gpio_lock_res = {
	.start = YU_ARM_GPIO_LOCK_ADDR,
	.end   = YU_ARM_GPIO_LOCK_ADDR + YU_ARM_GPIO_LOCK_SIZE - 1,
	.name  = "YU_ARM_GPIO_LOCK",
};

static DEFINE_MUTEX(yu_arm_gpio_lock_mutex);

static struct mlxbf2_gpio_param yu_arm_gpio_lock_param = {
	.res = &yu_arm_gpio_lock_res,
	.lock = &yu_arm_gpio_lock_mutex,
};

/* Request memory region and map yu_arm_gpio_lock resource */
static int mlxbf2_gpio_get_lock_res(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct resource *res;
	resource_size_t size;
	int ret = 0;

	mutex_lock(yu_arm_gpio_lock_param.lock);

	/* Check if the memory map already exists */
	if (yu_arm_gpio_lock_param.io)
		goto exit;

	res = yu_arm_gpio_lock_param.res;
	size = resource_size(res);

	if (!devm_request_mem_region(dev, res->start, size, res->name)) {
		ret = -EFAULT;
		goto exit;
	}

	yu_arm_gpio_lock_param.io = devm_ioremap(dev, res->start, size);
	if (!yu_arm_gpio_lock_param.io)
		ret = -ENOMEM;

exit:
	mutex_unlock(yu_arm_gpio_lock_param.lock);

	return ret;
}

/*
 * Acquire the YU arm_gpio_lock to be able to change the direction
 * mode. If the lock_active bit is already set, return an error.
 */
static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
{
	u32 arm_gpio_lock_val;

	mutex_lock(yu_arm_gpio_lock_param.lock);
	spin_lock(&gs->gc.bgpio_lock);

	arm_gpio_lock_val = readl(yu_arm_gpio_lock_param.io);

	/*
	 * When lock active bit[31] is set, ModeX is write enabled
	 */
	if (YU_LOCK_ACTIVE_BIT(arm_gpio_lock_val)) {
		spin_unlock(&gs->gc.bgpio_lock);
		mutex_unlock(yu_arm_gpio_lock_param.lock);
		return -EINVAL;
	}

	writel(YU_ARM_GPIO_LOCK_ACQUIRE, yu_arm_gpio_lock_param.io);

	return 0;
}

/*
 * Release the YU arm_gpio_lock after changing the direction mode.
 */
static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
{
	writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
	spin_unlock(&gs->gc.bgpio_lock);
	mutex_unlock(yu_arm_gpio_lock_param.lock);
}

/*
 * mode0 and mode1 are both locked by the gpio_lock field.
 *
 * Together, mode0 and mode1 define the gpio Mode dependeing also
 * on Reg_DataOut.
 *
 * {mode1,mode0}:{Reg_DataOut=0,Reg_DataOut=1}->{DataOut=0,DataOut=1}
 *
 * {0,0}:Reg_DataOut{0,1}->{Z,Z} Input PAD
 * {0,1}:Reg_DataOut{0,1}->{0,1} Full drive Output PAD
 * {1,0}:Reg_DataOut{0,1}->{0,Z} 0-set PAD to low, 1-float
 * {1,1}:Reg_DataOut{0,1}->{Z,1} 0-float, 1-set PAD to high
 */

/*
 * Set input direction:
 * {mode1,mode0} = {0,0}
 */
static int mlxbf2_gpio_direction_input(struct gpio_chip *chip,
				       unsigned int offset)
{
	struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
	int ret;

	/*
	 * Although the arm_gpio_lock was set in the probe function, check again
	 * if it is still enabled to be able to write to the ModeX registers.
	 */
	ret = mlxbf2_gpio_lock_acquire(gs);
	if (ret < 0)
		return ret;

	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_CLEAR);
	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);

	mlxbf2_gpio_lock_release(gs);

	return ret;
}

/*
 * Set output direction:
 * {mode1,mode0} = {0,1}
 */
static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
					unsigned int offset,
					int value)
{
	struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
	int ret = 0;

	/*
	 * Although the arm_gpio_lock was set in the probe function,
	 * check again it is still enabled to be able to write to the
	 * ModeX registers.
	 */
	ret = mlxbf2_gpio_lock_acquire(gs);
	if (ret < 0)
		return ret;

	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);
	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_SET);

	mlxbf2_gpio_lock_release(gs);

	return ret;
}

/* BlueField-2 GPIO driver initialization routine. */
static int
mlxbf2_gpio_probe(struct platform_device *pdev)
{
	struct mlxbf2_gpio_context *gs;
	struct device *dev = &pdev->dev;
	struct gpio_chip *gc;
	struct resource *res;
	unsigned int npins;
	int ret;

	gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
	if (!gs)
		return -ENOMEM;

	/* YU GPIO block address */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENODEV;

	gs->gpio_io = devm_ioremap(dev, res->start, resource_size(res));
	if (!gs->gpio_io)
		return -ENOMEM;

	ret = mlxbf2_gpio_get_lock_res(pdev);
	if (ret) {
		dev_err(dev, "Failed to get yu_arm_gpio_lock resource\n");
		return ret;
	}

	if (device_property_read_u32(dev, "npins", &npins))
		npins = MLXBF2_GPIO_MAX_PINS_PER_BLOCK;

	gc = &gs->gc;

	ret = bgpio_init(gc, dev, 4,
			gs->gpio_io + YU_GPIO_DATAIN,
			gs->gpio_io + YU_GPIO_DATASET,
			gs->gpio_io + YU_GPIO_DATACLEAR,
			NULL,
			NULL,
			0);

	gc->direction_input = mlxbf2_gpio_direction_input;
	gc->direction_output = mlxbf2_gpio_direction_output;
	gc->ngpio = npins;
	gc->owner = THIS_MODULE;

	platform_set_drvdata(pdev, gs);

	ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
	if (ret) {
		dev_err(dev, "Failed adding memory mapped gpiochip\n");
		return ret;
	}

	return 0;
}

#ifdef CONFIG_PM
static int mlxbf2_gpio_suspend(struct platform_device *pdev,
				pm_message_t state)
{
	struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);

	gs->csave_regs->gpio_mode0 = readl(gs->gpio_io +
		YU_GPIO_MODE0);
	gs->csave_regs->gpio_mode1 = readl(gs->gpio_io +
		YU_GPIO_MODE1);

	return 0;
}

static int mlxbf2_gpio_resume(struct platform_device *pdev)
{
	struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);

	writel(gs->csave_regs->gpio_mode0, gs->gpio_io +
		YU_GPIO_MODE0);
	writel(gs->csave_regs->gpio_mode1, gs->gpio_io +
		YU_GPIO_MODE1);

	return 0;
}
#endif

static const struct acpi_device_id mlxbf2_gpio_acpi_match[] = {
	{ "MLNXBF22", 0 },
	{},
};
MODULE_DEVICE_TABLE(acpi, mlxbf2_gpio_acpi_match);

static struct platform_driver mlxbf2_gpio_driver = {
	.driver = {
		.name = "mlxbf2_gpio",
		.acpi_match_table = ACPI_PTR(mlxbf2_gpio_acpi_match),
	},
	.probe    = mlxbf2_gpio_probe,
#ifdef CONFIG_PM
	.suspend  = mlxbf2_gpio_suspend,
	.resume   = mlxbf2_gpio_resume,
#endif
};

module_platform_driver(mlxbf2_gpio_driver);

MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver");
MODULE_AUTHOR("Mellanox Technologies");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
bc0ae0e7 AM	1	// SPDX-License-Identifier: GPL-2.0
	2
	3	#include <linux/acpi.h>
	4	#include <linux/bitfield.h>
	5	#include <linux/bitops.h>
	6	#include <linux/device.h>
	7	#include <linux/gpio/driver.h>
	8	#include <linux/io.h>
	9	#include <linux/ioport.h>
	10	#include <linux/kernel.h>
	11	#include <linux/module.h>
	12	#include <linux/platform_device.h>
	13	#include <linux/pm.h>
	14	#include <linux/resource.h>
	15	#include <linux/spinlock.h>
	16	#include <linux/types.h>
bc0ae0e7 AM	17
	18	/*
	19	* There are 3 YU GPIO blocks:
	20	* gpio[0]: HOST_GPIO0->HOST_GPIO31
	21	* gpio[1]: HOST_GPIO32->HOST_GPIO63
	22	* gpio[2]: HOST_GPIO64->HOST_GPIO69
	23	*/
	24	#define MLXBF2_GPIO_MAX_PINS_PER_BLOCK 32
	25
	26	/*
	27	* arm_gpio_lock register:
	28	* bit[31] lock status: active if set
	29	* bit[15:0] set lock
	30	* The lock is enabled only if 0xd42f is written to this field
	31	*/
	32	#define YU_ARM_GPIO_LOCK_ADDR 0x2801088
	33	#define YU_ARM_GPIO_LOCK_SIZE 0x8
	34	#define YU_LOCK_ACTIVE_BIT(val) (val >> 31)
	35	#define YU_ARM_GPIO_LOCK_ACQUIRE 0xd42f
	36	#define YU_ARM_GPIO_LOCK_RELEASE 0x0
	37
	38	/*
	39	* gpio[x] block registers and their offset
	40	*/
	41	#define YU_GPIO_DATAIN 0x04
	42	#define YU_GPIO_MODE1 0x08
	43	#define YU_GPIO_MODE0 0x0c
	44	#define YU_GPIO_DATASET 0x14
	45	#define YU_GPIO_DATACLEAR 0x18
	46	#define YU_GPIO_MODE1_CLEAR 0x50
	47	#define YU_GPIO_MODE0_SET 0x54
	48	#define YU_GPIO_MODE0_CLEAR 0x58
	49
	50	#ifdef CONFIG_PM
	51	struct mlxbf2_gpio_context_save_regs {
	52	u32 gpio_mode0;
	53	u32 gpio_mode1;
	54	};
	55	#endif
	56
	57	/* BlueField-2 gpio block context structure. */
	58	struct mlxbf2_gpio_context {
	59	struct gpio_chip gc;
	60
	61	/* YU GPIO blocks address */
	62	void __iomem *gpio_io;
	63
	64	#ifdef CONFIG_PM
	65	struct mlxbf2_gpio_context_save_regs *csave_regs;
	66	#endif
	67	};
	68
	69	/* BlueField-2 gpio shared structure. */
	70	struct mlxbf2_gpio_param {
	71	void __iomem *io;
	72	struct resource *res;
	73	struct mutex *lock;
	74	};
	75
	76	static struct resource yu_arm_gpio_lock_res = {
	77	.start = YU_ARM_GPIO_LOCK_ADDR,
	78	.end = YU_ARM_GPIO_LOCK_ADDR + YU_ARM_GPIO_LOCK_SIZE - 1,
	79	.name = "YU_ARM_GPIO_LOCK",
	80	};
81
82	static DEFINE_MUTEX(yu_arm_gpio_lock_mutex);
83
84	static struct mlxbf2_gpio_param yu_arm_gpio_lock_param = {
85	.res = &yu_arm_gpio_lock_res,
86	.lock = &yu_arm_gpio_lock_mutex,
87	};
88
89	/* Request memory region and map yu_arm_gpio_lock resource */
90	static int mlxbf2_gpio_get_lock_res(struct platform_device *pdev)
91	{
92	struct device *dev = &pdev->dev;
93	struct resource *res;
94	resource_size_t size;
95	int ret = 0;
96
97	mutex_lock(yu_arm_gpio_lock_param.lock);
98
99	/* Check if the memory map already exists */
100	if (yu_arm_gpio_lock_param.io)
101	goto exit;
102
103	res = yu_arm_gpio_lock_param.res;
104	size = resource_size(res);
105
106	if (!devm_request_mem_region(dev, res->start, size, res->name)) {
107	ret = -EFAULT;
108	goto exit;
109	}
110
111	yu_arm_gpio_lock_param.io = devm_ioremap(dev, res->start, size);
66d8ad67 WY	112	if (!yu_arm_gpio_lock_param.io)
66d8ad67 WY	113	ret = -ENOMEM;
bc0ae0e7 AM	114
	115	exit:
	116	mutex_unlock(yu_arm_gpio_lock_param.lock);
	117
	118	return ret;
	119	}
	120
	121	/*
	122	* Acquire the YU arm_gpio_lock to be able to change the direction
	123	* mode. If the lock_active bit is already set, return an error.
	124	*/
	125	static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
	126	{
	127	u32 arm_gpio_lock_val;
	128
bc0ae0e7	129	mutex_lock(yu_arm_gpio_lock_param.lock);
e6862430	130	spin_lock(&gs->gc.bgpio_lock);
bc0ae0e7 AM	131
	132	arm_gpio_lock_val = readl(yu_arm_gpio_lock_param.io);
	133
	134	/*
	135	* When lock active bit[31] is set, ModeX is write enabled
	136	*/
	137	if (YU_LOCK_ACTIVE_BIT(arm_gpio_lock_val)) {
bc0ae0e7	138	spin_unlock(&gs->gc.bgpio_lock);
e6862430	139	mutex_unlock(yu_arm_gpio_lock_param.lock);
bc0ae0e7 AM	140	return -EINVAL;
	141	}
	142
	143	writel(YU_ARM_GPIO_LOCK_ACQUIRE, yu_arm_gpio_lock_param.io);
	144
	145	return 0;
	146	}
	147
	148	/*
	149	* Release the YU arm_gpio_lock after changing the direction mode.
	150	*/
	151	static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
	152	{
	153	writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
bc0ae0e7	154	spin_unlock(&gs->gc.bgpio_lock);
e6862430	155	mutex_unlock(yu_arm_gpio_lock_param.lock);
bc0ae0e7 AM	156	}
	157
	158	/*
	159	* mode0 and mode1 are both locked by the gpio_lock field.
	160	*
	161	* Together, mode0 and mode1 define the gpio Mode dependeing also
	162	* on Reg_DataOut.
	163	*
	164	* {mode1,mode0}:{Reg_DataOut=0,Reg_DataOut=1}->{DataOut=0,DataOut=1}
	165	*
	166	* {0,0}:Reg_DataOut{0,1}->{Z,Z} Input PAD
	167	* {0,1}:Reg_DataOut{0,1}->{0,1} Full drive Output PAD
	168	* {1,0}:Reg_DataOut{0,1}->{0,Z} 0-set PAD to low, 1-float
	169	* {1,1}:Reg_DataOut{0,1}->{Z,1} 0-float, 1-set PAD to high
	170	*/
	171
	172	/*
	173	* Set input direction:
	174	* {mode1,mode0} = {0,0}
	175	*/
	176	static int mlxbf2_gpio_direction_input(struct gpio_chip *chip,
	177	unsigned int offset)
	178	{
	179	struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
	180	int ret;
	181
	182	/*
	183	* Although the arm_gpio_lock was set in the probe function, check again
	184	* if it is still enabled to be able to write to the ModeX registers.
	185	*/
	186	ret = mlxbf2_gpio_lock_acquire(gs);
	187	if (ret < 0)
	188	return ret;
	189
	190	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_CLEAR);
	191	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);
	192
	193	mlxbf2_gpio_lock_release(gs);
	194
	195	return ret;
	196	}
	197
	198	/*
	199	* Set output direction:
	200	* {mode1,mode0} = {0,1}
	201	*/
	202	static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
	203	unsigned int offset,
	204	int value)
	205	{
	206	struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
	207	int ret = 0;
	208
	209	/*
	210	* Although the arm_gpio_lock was set in the probe function,
	211	* check again it is still enabled to be able to write to the
	212	* ModeX registers.
	213	*/
	214	ret = mlxbf2_gpio_lock_acquire(gs);
	215	if (ret < 0)
	216	return ret;
	217
	218	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);
	219	writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_SET);
220
221	mlxbf2_gpio_lock_release(gs);
222
223	return ret;
224	}
225
226	/* BlueField-2 GPIO driver initialization routine. */
227	static int
228	mlxbf2_gpio_probe(struct platform_device *pdev)
229	{
230	struct mlxbf2_gpio_context *gs;
231	struct device *dev = &pdev->dev;
232	struct gpio_chip *gc;
233	struct resource *res;
234	unsigned int npins;
235	int ret;
236
237	gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
238	if (!gs)
239	return -ENOMEM;
240
241	/* YU GPIO block address */
242	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
243	if (!res)
244	return -ENODEV;
245
246	gs->gpio_io = devm_ioremap(dev, res->start, resource_size(res));
247	if (!gs->gpio_io)
248	return -ENOMEM;
249
250	ret = mlxbf2_gpio_get_lock_res(pdev);
251	if (ret) {
252	dev_err(dev, "Failed to get yu_arm_gpio_lock resource\n");
253	return ret;
254	}
255
256	if (device_property_read_u32(dev, "npins", &npins))
257	npins = MLXBF2_GPIO_MAX_PINS_PER_BLOCK;
258
259	gc = &gs->gc;
260
261	ret = bgpio_init(gc, dev, 4,
262	gs->gpio_io + YU_GPIO_DATAIN,
263	gs->gpio_io + YU_GPIO_DATASET,
264	gs->gpio_io + YU_GPIO_DATACLEAR,
265	NULL,
266	NULL,
267	0);
268
269	gc->direction_input = mlxbf2_gpio_direction_input;
270	gc->direction_output = mlxbf2_gpio_direction_output;
271	gc->ngpio = npins;
272	gc->owner = THIS_MODULE;
273
274	platform_set_drvdata(pdev, gs);
275
276	ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
277	if (ret) {
278	dev_err(dev, "Failed adding memory mapped gpiochip\n");
279	return ret;
280	}
281
282	return 0;
283	}
284
285	#ifdef CONFIG_PM
286	static int mlxbf2_gpio_suspend(struct platform_device *pdev,
287	pm_message_t state)
288	{
289	struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);
290
291	gs->csave_regs->gpio_mode0 = readl(gs->gpio_io +
292	YU_GPIO_MODE0);
293	gs->csave_regs->gpio_mode1 = readl(gs->gpio_io +
294	YU_GPIO_MODE1);
295
296	return 0;
297	}
298
299	static int mlxbf2_gpio_resume(struct platform_device *pdev)
300	{
301	struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);
302
303	writel(gs->csave_regs->gpio_mode0, gs->gpio_io +
304	YU_GPIO_MODE0);
305	writel(gs->csave_regs->gpio_mode1, gs->gpio_io +
306	YU_GPIO_MODE1);
307
308	return 0;
309	}
310	#endif
311
312	static const struct acpi_device_id mlxbf2_gpio_acpi_match[] = {
313	{ "MLNXBF22", 0 },
314	{},
315	};
316	MODULE_DEVICE_TABLE(acpi, mlxbf2_gpio_acpi_match);
317
318	static struct platform_driver mlxbf2_gpio_driver = {
319	.driver = {
320	.name = "mlxbf2_gpio",
321	.acpi_match_table = ACPI_PTR(mlxbf2_gpio_acpi_match),
322	},
323	.probe = mlxbf2_gpio_probe,
324	#ifdef CONFIG_PM
325	.suspend = mlxbf2_gpio_suspend,
326	.resume = mlxbf2_gpio_resume,
327	#endif
328	};
329
330	module_platform_driver(mlxbf2_gpio_driver);
331
332	MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver");
333	MODULE_AUTHOR("Mellanox Technologies");
334	MODULE_LICENSE("GPL v2");