1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2018 MediaTek Inc.
4 *
5 * Author: Ryder Lee <ryder.lee@mediatek.com>
6 * Weijie Gao <weijie.gao@mediatek.com>
7 */
8
9 #include <common.h>
10 #include <dm.h>
11 #include <log.h>
12 #include <malloc.h>
13 #include <dm/lists.h>
14 #include <regmap.h>
15 #include <reset-uclass.h>
16 #include <syscon.h>
17 #include <dm/device-internal.h>
18 #include <linux/bitops.h>
19 #include <linux/err.h>
20
21 struct mediatek_reset_priv {
22 struct regmap *regmap;
23 u32 regofs;
24 u32 nr_resets;
25 };
26
mediatek_reset_assert(struct reset_ctl * reset_ctl)27 static int mediatek_reset_assert(struct reset_ctl *reset_ctl)
28 {
29 struct mediatek_reset_priv *priv = dev_get_priv(reset_ctl->dev);
30 int id = reset_ctl->id;
31
32 if (id >= priv->nr_resets)
33 return -EINVAL;
34
35 return regmap_update_bits(priv->regmap,
36 priv->regofs + ((id / 32) << 2), BIT(id % 32), BIT(id % 32));
37 }
38
mediatek_reset_deassert(struct reset_ctl * reset_ctl)39 static int mediatek_reset_deassert(struct reset_ctl *reset_ctl)
40 {
41 struct mediatek_reset_priv *priv = dev_get_priv(reset_ctl->dev);
42 int id = reset_ctl->id;
43
44 if (id >= priv->nr_resets)
45 return -EINVAL;
46
47 return regmap_update_bits(priv->regmap,
48 priv->regofs + ((id / 32) << 2), BIT(id % 32), 0);
49 }
50
51 struct reset_ops mediatek_reset_ops = {
52 .rst_assert = mediatek_reset_assert,
53 .rst_deassert = mediatek_reset_deassert,
54 };
55
mediatek_reset_probe(struct udevice * dev)56 static int mediatek_reset_probe(struct udevice *dev)
57 {
58 struct mediatek_reset_priv *priv = dev_get_priv(dev);
59
60 if (!priv->regofs && !priv->nr_resets)
61 return -EINVAL;
62
63 priv->regmap = syscon_node_to_regmap(dev_ofnode(dev));
64 if (IS_ERR(priv->regmap))
65 return PTR_ERR(priv->regmap);
66
67 return 0;
68 }
69
mediatek_reset_bind(struct udevice * pdev,u32 regofs,u32 num_regs)70 int mediatek_reset_bind(struct udevice *pdev, u32 regofs, u32 num_regs)
71 {
72 struct udevice *rst_dev;
73 struct mediatek_reset_priv *priv;
74 int ret;
75
76 ret = device_bind_driver_to_node(pdev, "mediatek_reset", "reset",
77 dev_ofnode(pdev), &rst_dev);
78 if (ret)
79 return ret;
80
81 priv = malloc(sizeof(struct mediatek_reset_priv));
82 priv->regofs = regofs;
83 priv->nr_resets = num_regs * 32;
84 dev_set_priv(rst_dev, priv);
85
86 return 0;
87 }
88
89 U_BOOT_DRIVER(mediatek_reset) = {
90 .name = "mediatek_reset",
91 .id = UCLASS_RESET,
92 .probe = mediatek_reset_probe,
93 .ops = &mediatek_reset_ops,
94 .priv_auto = sizeof(struct mediatek_reset_priv),
95 };
96