meson-aoclk.c

 1// SPDX-License-Identifier: GPL-2.0+
 2/*
 3 * Amlogic Meson-AXG Clock Controller Driver
 4 *
 5 * Copyright (c) 2016 BayLibre, SAS.
 6 * Author: Neil Armstrong <narmstrong@baylibre.com>
 7 *
 8 * Copyright (c) 2018 Amlogic, inc.
 9 * Author: Qiufang Dai <qiufang.dai@amlogic.com>
10 * Author: Yixun Lan <yixun.lan@amlogic.com>
11 */
12
13#include <linux/platform_device.h>
14#include <linux/reset-controller.h>
15#include <linux/mfd/syscon.h>
16#include <linux/of.h>
17#include <linux/module.h>
18
19#include <linux/slab.h>
20#include "meson-aoclk.h"
21#include "clk-regmap.h"
22
23static int meson_aoclk_do_reset(struct reset_controller_dev *rcdev,
24			       unsigned long id)
25{
26	struct meson_aoclk_reset_controller *rstc =
27		container_of(rcdev, struct meson_aoclk_reset_controller, reset);
28
29	return regmap_write(rstc->regmap, rstc->data->reset_reg,
30			    BIT(rstc->data->reset[id]));
31}
32
33static const struct reset_control_ops meson_aoclk_reset_ops = {
34	.reset = meson_aoclk_do_reset,
35};
36
37int meson_aoclkc_probe(struct platform_device *pdev)
38{
39	struct meson_aoclk_reset_controller *rstc;
40	const struct meson_clkc_data *clkc_data;
41	const struct meson_aoclk_data *data;
42	struct device *dev = &pdev->dev;
43	struct device_node *np;
44	struct regmap *regmap;
45	int ret;
46
47	clkc_data = of_device_get_match_data(dev);
48	if (!clkc_data)
49		return -EINVAL;
50
51	ret = meson_clkc_syscon_probe(pdev);
52	if (ret)
53		return ret;
54
55	data = container_of(clkc_data, struct meson_aoclk_data,
56			    clkc_data);
57
58	rstc = devm_kzalloc(dev, sizeof(*rstc), GFP_KERNEL);
59	if (!rstc)
60		return -ENOMEM;
61
62	np = of_get_parent(dev->of_node);
63	regmap = syscon_node_to_regmap(np);
64	of_node_put(np);
65	if (IS_ERR(regmap)) {
66		dev_err(dev, "failed to get regmap\n");
67		return PTR_ERR(regmap);
68	}
69
70	/* Reset Controller */
71	rstc->data = data;
72	rstc->regmap = regmap;
73	rstc->reset.ops = &meson_aoclk_reset_ops;
74	rstc->reset.nr_resets = data->num_reset;
75	rstc->reset.of_node = dev->of_node;
76	ret = devm_reset_controller_register(dev, &rstc->reset);
77	if (ret) {
78		dev_err(dev, "failed to register reset controller\n");
79		return ret;
80	}
81
82	return 0;
83}
84EXPORT_SYMBOL_NS_GPL(meson_aoclkc_probe, "CLK_MESON");
85
86MODULE_DESCRIPTION("Amlogic Always-ON Clock Controller helpers");
87MODULE_LICENSE("GPL");
88MODULE_IMPORT_NS("CLK_MESON");