1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
4 */
5
6 #include <linux/bitops.h>
7 #include <linux/export.h>
8 #include <linux/regmap.h>
9 #include <linux/reset-controller.h>
10 #include <linux/delay.h>
11
12 #include "reset.h"
13
qcom_reset(struct reset_controller_dev * rcdev,unsigned long id)14 static int qcom_reset(struct reset_controller_dev *rcdev, unsigned long id)
15 {
16 struct qcom_reset_controller *rst = to_qcom_reset_controller(rcdev);
17
18 rcdev->ops->assert(rcdev, id);
19 udelay(rst->reset_map[id].udelay ?: 1); /* use 1 us as default */
20 rcdev->ops->deassert(rcdev, id);
21 return 0;
22 }
23
qcom_reset_set_assert(struct reset_controller_dev * rcdev,unsigned long id,bool assert)24 static int qcom_reset_set_assert(struct reset_controller_dev *rcdev,
25 unsigned long id, bool assert)
26 {
27 struct qcom_reset_controller *rst;
28 const struct qcom_reset_map *map;
29 u32 mask;
30
31 rst = to_qcom_reset_controller(rcdev);
32 map = &rst->reset_map[id];
33 mask = map->bitmask ? map->bitmask : BIT(map->bit);
34
35 regmap_update_bits(rst->regmap, map->reg, mask, assert ? mask : 0);
36
37 /* Read back the register to ensure write completion, ignore the value */
38 regmap_read(rst->regmap, map->reg, &mask);
39
40 return 0;
41 }
42
qcom_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)43 static int qcom_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
44 {
45 return qcom_reset_set_assert(rcdev, id, true);
46 }
47
qcom_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)48 static int qcom_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
49 {
50 return qcom_reset_set_assert(rcdev, id, false);
51 }
52
53 const struct reset_control_ops qcom_reset_ops = {
54 .reset = qcom_reset,
55 .assert = qcom_reset_assert,
56 .deassert = qcom_reset_deassert,
57 };
58 EXPORT_SYMBOL_GPL(qcom_reset_ops);
59