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v5.9
  1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
  2/*
  3 * Amlogic Meson Reset Controller driver
  4 *
  5 * Copyright (c) 2016 BayLibre, SAS.
  6 * Author: Neil Armstrong <narmstrong@baylibre.com>
  7 */
  8#include <linux/err.h>
  9#include <linux/init.h>
 10#include <linux/io.h>
 11#include <linux/of.h>
 12#include <linux/platform_device.h>
 13#include <linux/reset-controller.h>
 14#include <linux/slab.h>
 15#include <linux/types.h>
 16#include <linux/of_device.h>
 17
 
 18#define BITS_PER_REG	32
 19
 20struct meson_reset_param {
 21	int reg_count;
 22	int level_offset;
 23};
 24
 25struct meson_reset {
 26	void __iomem *reg_base;
 27	const struct meson_reset_param *param;
 28	struct reset_controller_dev rcdev;
 29	spinlock_t lock;
 30};
 31
 32static int meson_reset_reset(struct reset_controller_dev *rcdev,
 33			      unsigned long id)
 34{
 35	struct meson_reset *data =
 36		container_of(rcdev, struct meson_reset, rcdev);
 37	unsigned int bank = id / BITS_PER_REG;
 38	unsigned int offset = id % BITS_PER_REG;
 39	void __iomem *reg_addr = data->reg_base + (bank << 2);
 40
 41	writel(BIT(offset), reg_addr);
 42
 43	return 0;
 44}
 45
 46static int meson_reset_level(struct reset_controller_dev *rcdev,
 47			    unsigned long id, bool assert)
 48{
 49	struct meson_reset *data =
 50		container_of(rcdev, struct meson_reset, rcdev);
 51	unsigned int bank = id / BITS_PER_REG;
 52	unsigned int offset = id % BITS_PER_REG;
 53	void __iomem *reg_addr;
 54	unsigned long flags;
 55	u32 reg;
 56
 57	reg_addr = data->reg_base + data->param->level_offset + (bank << 2);
 58
 59	spin_lock_irqsave(&data->lock, flags);
 60
 61	reg = readl(reg_addr);
 62	if (assert)
 63		writel(reg & ~BIT(offset), reg_addr);
 64	else
 65		writel(reg | BIT(offset), reg_addr);
 66
 67	spin_unlock_irqrestore(&data->lock, flags);
 68
 69	return 0;
 70}
 71
 72static int meson_reset_assert(struct reset_controller_dev *rcdev,
 73			      unsigned long id)
 74{
 75	return meson_reset_level(rcdev, id, true);
 76}
 77
 78static int meson_reset_deassert(struct reset_controller_dev *rcdev,
 79				unsigned long id)
 80{
 81	return meson_reset_level(rcdev, id, false);
 82}
 83
 84static const struct reset_control_ops meson_reset_ops = {
 85	.reset		= meson_reset_reset,
 86	.assert		= meson_reset_assert,
 87	.deassert	= meson_reset_deassert,
 88};
 89
 90static const struct meson_reset_param meson8b_param = {
 91	.reg_count	= 8,
 92	.level_offset	= 0x7c,
 93};
 94
 95static const struct meson_reset_param meson_a1_param = {
 96	.reg_count	= 3,
 97	.level_offset	= 0x40,
 98};
 99
100static const struct of_device_id meson_reset_dt_ids[] = {
101	 { .compatible = "amlogic,meson8b-reset",    .data = &meson8b_param},
102	 { .compatible = "amlogic,meson-gxbb-reset", .data = &meson8b_param},
103	 { .compatible = "amlogic,meson-axg-reset",  .data = &meson8b_param},
104	 { .compatible = "amlogic,meson-a1-reset",   .data = &meson_a1_param},
105	 { /* sentinel */ },
106};
107
108static int meson_reset_probe(struct platform_device *pdev)
109{
110	struct meson_reset *data;
111	struct resource *res;
112
113	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
114	if (!data)
115		return -ENOMEM;
116
117	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
118	data->reg_base = devm_ioremap_resource(&pdev->dev, res);
119	if (IS_ERR(data->reg_base))
120		return PTR_ERR(data->reg_base);
121
122	data->param = of_device_get_match_data(&pdev->dev);
123	if (!data->param)
124		return -ENODEV;
125
126	platform_set_drvdata(pdev, data);
127
128	spin_lock_init(&data->lock);
129
130	data->rcdev.owner = THIS_MODULE;
131	data->rcdev.nr_resets = data->param->reg_count * BITS_PER_REG;
132	data->rcdev.ops = &meson_reset_ops;
133	data->rcdev.of_node = pdev->dev.of_node;
134
135	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
136}
137
138static struct platform_driver meson_reset_driver = {
139	.probe	= meson_reset_probe,
140	.driver = {
141		.name		= "meson_reset",
142		.of_match_table	= meson_reset_dt_ids,
143	},
144};
145builtin_platform_driver(meson_reset_driver);
v5.4
  1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
  2/*
  3 * Amlogic Meson Reset Controller driver
  4 *
  5 * Copyright (c) 2016 BayLibre, SAS.
  6 * Author: Neil Armstrong <narmstrong@baylibre.com>
  7 */
  8#include <linux/err.h>
  9#include <linux/init.h>
 10#include <linux/io.h>
 11#include <linux/of.h>
 12#include <linux/platform_device.h>
 13#include <linux/reset-controller.h>
 14#include <linux/slab.h>
 15#include <linux/types.h>
 16#include <linux/of_device.h>
 17
 18#define REG_COUNT	8
 19#define BITS_PER_REG	32
 20#define LEVEL_OFFSET	0x7c
 
 
 
 
 21
 22struct meson_reset {
 23	void __iomem *reg_base;
 
 24	struct reset_controller_dev rcdev;
 25	spinlock_t lock;
 26};
 27
 28static int meson_reset_reset(struct reset_controller_dev *rcdev,
 29			      unsigned long id)
 30{
 31	struct meson_reset *data =
 32		container_of(rcdev, struct meson_reset, rcdev);
 33	unsigned int bank = id / BITS_PER_REG;
 34	unsigned int offset = id % BITS_PER_REG;
 35	void __iomem *reg_addr = data->reg_base + (bank << 2);
 36
 37	writel(BIT(offset), reg_addr);
 38
 39	return 0;
 40}
 41
 42static int meson_reset_level(struct reset_controller_dev *rcdev,
 43			    unsigned long id, bool assert)
 44{
 45	struct meson_reset *data =
 46		container_of(rcdev, struct meson_reset, rcdev);
 47	unsigned int bank = id / BITS_PER_REG;
 48	unsigned int offset = id % BITS_PER_REG;
 49	void __iomem *reg_addr = data->reg_base + LEVEL_OFFSET + (bank << 2);
 50	unsigned long flags;
 51	u32 reg;
 52
 
 
 53	spin_lock_irqsave(&data->lock, flags);
 54
 55	reg = readl(reg_addr);
 56	if (assert)
 57		writel(reg & ~BIT(offset), reg_addr);
 58	else
 59		writel(reg | BIT(offset), reg_addr);
 60
 61	spin_unlock_irqrestore(&data->lock, flags);
 62
 63	return 0;
 64}
 65
 66static int meson_reset_assert(struct reset_controller_dev *rcdev,
 67			      unsigned long id)
 68{
 69	return meson_reset_level(rcdev, id, true);
 70}
 71
 72static int meson_reset_deassert(struct reset_controller_dev *rcdev,
 73				unsigned long id)
 74{
 75	return meson_reset_level(rcdev, id, false);
 76}
 77
 78static const struct reset_control_ops meson_reset_ops = {
 79	.reset		= meson_reset_reset,
 80	.assert		= meson_reset_assert,
 81	.deassert	= meson_reset_deassert,
 82};
 83
 
 
 
 
 
 
 
 
 
 
 84static const struct of_device_id meson_reset_dt_ids[] = {
 85	 { .compatible = "amlogic,meson8b-reset" },
 86	 { .compatible = "amlogic,meson-gxbb-reset" },
 87	 { .compatible = "amlogic,meson-axg-reset" },
 
 88	 { /* sentinel */ },
 89};
 90
 91static int meson_reset_probe(struct platform_device *pdev)
 92{
 93	struct meson_reset *data;
 94	struct resource *res;
 95
 96	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 97	if (!data)
 98		return -ENOMEM;
 99
100	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
101	data->reg_base = devm_ioremap_resource(&pdev->dev, res);
102	if (IS_ERR(data->reg_base))
103		return PTR_ERR(data->reg_base);
104
 
 
 
 
105	platform_set_drvdata(pdev, data);
106
107	spin_lock_init(&data->lock);
108
109	data->rcdev.owner = THIS_MODULE;
110	data->rcdev.nr_resets = REG_COUNT * BITS_PER_REG;
111	data->rcdev.ops = &meson_reset_ops;
112	data->rcdev.of_node = pdev->dev.of_node;
113
114	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
115}
116
117static struct platform_driver meson_reset_driver = {
118	.probe	= meson_reset_probe,
119	.driver = {
120		.name		= "meson_reset",
121		.of_match_table	= meson_reset_dt_ids,
122	},
123};
124builtin_platform_driver(meson_reset_driver);