[linux-2.6-block.git] / drivers / hwspinlock / sirf_hwspinlock.c

// SPDX-License-Identifier: GPL-2.0
/*
 * SIRF hardware spinlock driver
 *
 * Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/hwspinlock.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_address.h>

#include "hwspinlock_internal.h"

struct sirf_hwspinlock {
	void __iomem *io_base;
	struct hwspinlock_device bank;
};

/* Number of Hardware Spinlocks*/
#define	HW_SPINLOCK_NUMBER	30

/* Hardware spinlock register offsets */
#define HW_SPINLOCK_BASE	0x404
#define HW_SPINLOCK_OFFSET(x)	(HW_SPINLOCK_BASE + 0x4 * (x))

static int sirf_hwspinlock_trylock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	/* attempt to acquire the lock by reading value == 1 from it */
	return !!readl(lock_addr);
}

static void sirf_hwspinlock_unlock(struct hwspinlock *lock)
{
	void __iomem *lock_addr = lock->priv;

	/* release the lock by writing 0 to it */
	writel(0, lock_addr);
}

static const struct hwspinlock_ops sirf_hwspinlock_ops = {
	.trylock = sirf_hwspinlock_trylock,
	.unlock = sirf_hwspinlock_unlock,
};

static int sirf_hwspinlock_probe(struct platform_device *pdev)
{
	struct sirf_hwspinlock *hwspin;
	struct hwspinlock *hwlock;
	int idx, ret;

	if (!pdev->dev.of_node)
		return -ENODEV;

	hwspin = devm_kzalloc(&pdev->dev,
			      struct_size(hwspin, bank.lock,
					  HW_SPINLOCK_NUMBER),
			      GFP_KERNEL);
	if (!hwspin)
		return -ENOMEM;

	/* retrieve io base */
	hwspin->io_base = of_iomap(pdev->dev.of_node, 0);
	if (!hwspin->io_base)
		return -ENOMEM;

	for (idx = 0; idx < HW_SPINLOCK_NUMBER; idx++) {
		hwlock = &hwspin->bank.lock[idx];
		hwlock->priv = hwspin->io_base + HW_SPINLOCK_OFFSET(idx);
	}

	platform_set_drvdata(pdev, hwspin);

	pm_runtime_enable(&pdev->dev);

	ret = hwspin_lock_register(&hwspin->bank, &pdev->dev,
				   &sirf_hwspinlock_ops, 0,
				   HW_SPINLOCK_NUMBER);
	if (ret)
		goto reg_failed;

	return 0;

reg_failed:
	pm_runtime_disable(&pdev->dev);
	iounmap(hwspin->io_base);

	return ret;
}

static int sirf_hwspinlock_remove(struct platform_device *pdev)
{
	struct sirf_hwspinlock *hwspin = platform_get_drvdata(pdev);
	int ret;

	ret = hwspin_lock_unregister(&hwspin->bank);
	if (ret) {
		dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
		return ret;
	}

	pm_runtime_disable(&pdev->dev);

	iounmap(hwspin->io_base);

	return 0;
}

static const struct of_device_id sirf_hwpinlock_ids[] = {
	{ .compatible = "sirf,hwspinlock", },
	{},
};
MODULE_DEVICE_TABLE(of, sirf_hwpinlock_ids);

static struct platform_driver sirf_hwspinlock_driver = {
	.probe = sirf_hwspinlock_probe,
	.remove = sirf_hwspinlock_remove,
	.driver = {
		.name = "atlas7_hwspinlock",
		.of_match_table = of_match_ptr(sirf_hwpinlock_ids),
	},
};

module_platform_driver(sirf_hwspinlock_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("SIRF Hardware spinlock driver");
MODULE_AUTHOR("Wei Chen <wei.chen@csr.com>");
Commit	Line	Data
50a52280	1	// SPDX-License-Identifier: GPL-2.0
cc16d664 WC	2	/*
	3	* SIRF hardware spinlock driver
	4	*
	5	* Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company.
cc16d664 WC	6	*/
	7
	8	#include <linux/kernel.h>
	9	#include <linux/module.h>
	10	#include <linux/device.h>
	11	#include <linux/io.h>
	12	#include <linux/pm_runtime.h>
	13	#include <linux/slab.h>
	14	#include <linux/spinlock.h>
	15	#include <linux/hwspinlock.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/of.h>
	18	#include <linux/of_address.h>
	19
	20	#include "hwspinlock_internal.h"
	21
	22	struct sirf_hwspinlock {
	23	void __iomem *io_base;
	24	struct hwspinlock_device bank;
	25	};
	26
	27	/* Number of Hardware Spinlocks*/
	28	#define HW_SPINLOCK_NUMBER 30
	29
	30	/* Hardware spinlock register offsets */
	31	#define HW_SPINLOCK_BASE 0x404
	32	#define HW_SPINLOCK_OFFSET(x) (HW_SPINLOCK_BASE + 0x4 * (x))
	33
	34	static int sirf_hwspinlock_trylock(struct hwspinlock *lock)
	35	{
	36	void __iomem *lock_addr = lock->priv;
	37
	38	/* attempt to acquire the lock by reading value == 1 from it */
	39	return !!readl(lock_addr);
	40	}
	41
	42	static void sirf_hwspinlock_unlock(struct hwspinlock *lock)
	43	{
	44	void __iomem *lock_addr = lock->priv;
	45
	46	/* release the lock by writing 0 to it */
	47	writel(0, lock_addr);
	48	}
	49
	50	static const struct hwspinlock_ops sirf_hwspinlock_ops = {
	51	.trylock = sirf_hwspinlock_trylock,
	52	.unlock = sirf_hwspinlock_unlock,
	53	};
	54
	55	static int sirf_hwspinlock_probe(struct platform_device *pdev)
	56	{
	57	struct sirf_hwspinlock *hwspin;
	58	struct hwspinlock *hwlock;
	59	int idx, ret;
	60
	61	if (!pdev->dev.of_node)
	62	return -ENODEV;
	63
0ed2dd03 KC	64	hwspin = devm_kzalloc(&pdev->dev,
	65	struct_size(hwspin, bank.lock,
	66	HW_SPINLOCK_NUMBER),
	67	GFP_KERNEL);
cc16d664 WC	68	if (!hwspin)
	69	return -ENOMEM;
	70
	71	/* retrieve io base */
	72	hwspin->io_base = of_iomap(pdev->dev.of_node, 0);
	73	if (!hwspin->io_base)
	74	return -ENOMEM;
	75
	76	for (idx = 0; idx < HW_SPINLOCK_NUMBER; idx++) {
	77	hwlock = &hwspin->bank.lock[idx];
	78	hwlock->priv = hwspin->io_base + HW_SPINLOCK_OFFSET(idx);
	79	}
	80
	81	platform_set_drvdata(pdev, hwspin);
	82
	83	pm_runtime_enable(&pdev->dev);
	84
	85	ret = hwspin_lock_register(&hwspin->bank, &pdev->dev,
	86	&sirf_hwspinlock_ops, 0,
	87	HW_SPINLOCK_NUMBER);
	88	if (ret)
	89	goto reg_failed;
	90
	91	return 0;
	92
	93	reg_failed:
	94	pm_runtime_disable(&pdev->dev);
	95	iounmap(hwspin->io_base);
	96
	97	return ret;
	98	}
	99
	100	static int sirf_hwspinlock_remove(struct platform_device *pdev)
	101	{
	102	struct sirf_hwspinlock *hwspin = platform_get_drvdata(pdev);
	103	int ret;
	104
	105	ret = hwspin_lock_unregister(&hwspin->bank);
	106	if (ret) {
	107	dev_err(&pdev->dev, "%s failed: %d\n", __func__, ret);
	108	return ret;
	109	}
	110
	111	pm_runtime_disable(&pdev->dev);
	112
	113	iounmap(hwspin->io_base);
	114
	115	return 0;
	116	}
	117
	118	static const struct of_device_id sirf_hwpinlock_ids[] = {
	119	{ .compatible = "sirf,hwspinlock", },
	120	{},
	121	};
	122	MODULE_DEVICE_TABLE(of, sirf_hwpinlock_ids);
	123
	124	static struct platform_driver sirf_hwspinlock_driver = {
	125	.probe = sirf_hwspinlock_probe,
	126	.remove = sirf_hwspinlock_remove,
	127	.driver = {
	128	.name = "atlas7_hwspinlock",
	129	.of_match_table = of_match_ptr(sirf_hwpinlock_ids),
	130	},
	131	};
132
133	module_platform_driver(sirf_hwspinlock_driver);
134
135	MODULE_LICENSE("GPL v2");
136	MODULE_DESCRIPTION("SIRF Hardware spinlock driver");
137	MODULE_AUTHOR("Wei Chen <wei.chen@csr.com>");