| Zhangfei Gao | 1527058 | 2016-12-06 09:51:32 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016-2017 Linaro Ltd. |
| 3 | * Copyright (c) 2016-2017 HiSilicon Technologies Co., Ltd. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version 2 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | */ |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/mfd/syscon.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/of_device.h> |
| 14 | #include <linux/platform_device.h> |
| 15 | #include <linux/regmap.h> |
| 16 | #include <linux/reset-controller.h> |
| 17 | |
| 18 | struct hi3660_reset_controller { |
| 19 | struct reset_controller_dev rst; |
| 20 | struct regmap *map; |
| 21 | }; |
| 22 | |
| 23 | #define to_hi3660_reset_controller(_rst) \ |
| 24 | container_of(_rst, struct hi3660_reset_controller, rst) |
| 25 | |
| 26 | static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev, |
| 27 | unsigned long idx, bool assert) |
| 28 | { |
| 29 | struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev); |
| 30 | unsigned int offset = idx >> 8; |
| 31 | unsigned int mask = BIT(idx & 0x1f); |
| 32 | |
| 33 | if (assert) |
| 34 | return regmap_write(rc->map, offset, mask); |
| 35 | else |
| 36 | return regmap_write(rc->map, offset + 4, mask); |
| 37 | } |
| 38 | |
| 39 | static int hi3660_reset_assert(struct reset_controller_dev *rcdev, |
| 40 | unsigned long idx) |
| 41 | { |
| 42 | return hi3660_reset_program_hw(rcdev, idx, true); |
| 43 | } |
| 44 | |
| 45 | static int hi3660_reset_deassert(struct reset_controller_dev *rcdev, |
| 46 | unsigned long idx) |
| 47 | { |
| 48 | return hi3660_reset_program_hw(rcdev, idx, false); |
| 49 | } |
| 50 | |
| 51 | static int hi3660_reset_dev(struct reset_controller_dev *rcdev, |
| 52 | unsigned long idx) |
| 53 | { |
| 54 | int err; |
| 55 | |
| 56 | err = hi3660_reset_assert(rcdev, idx); |
| 57 | if (err) |
| 58 | return err; |
| 59 | |
| 60 | return hi3660_reset_deassert(rcdev, idx); |
| 61 | } |
| 62 | |
| 63 | static struct reset_control_ops hi3660_reset_ops = { |
| 64 | .reset = hi3660_reset_dev, |
| 65 | .assert = hi3660_reset_assert, |
| 66 | .deassert = hi3660_reset_deassert, |
| 67 | }; |
| 68 | |
| 69 | static int hi3660_reset_xlate(struct reset_controller_dev *rcdev, |
| 70 | const struct of_phandle_args *reset_spec) |
| 71 | { |
| 72 | unsigned int offset, bit; |
| 73 | |
| 74 | offset = reset_spec->args[0]; |
| 75 | bit = reset_spec->args[1]; |
| 76 | |
| 77 | return (offset << 8) | bit; |
| 78 | } |
| 79 | |
| 80 | static int hi3660_reset_probe(struct platform_device *pdev) |
| 81 | { |
| 82 | struct hi3660_reset_controller *rc; |
| 83 | struct device_node *np = pdev->dev.of_node; |
| 84 | struct device *dev = &pdev->dev; |
| 85 | |
| 86 | rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL); |
| 87 | if (!rc) |
| 88 | return -ENOMEM; |
| 89 | |
| 90 | rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon"); |
| 91 | if (IS_ERR(rc->map)) { |
| 92 | dev_err(dev, "failed to get hi3660,rst-syscon\n"); |
| 93 | return PTR_ERR(rc->map); |
| 94 | } |
| 95 | |
| 96 | rc->rst.ops = &hi3660_reset_ops, |
| 97 | rc->rst.of_node = np; |
| 98 | rc->rst.of_reset_n_cells = 2; |
| 99 | rc->rst.of_xlate = hi3660_reset_xlate; |
| 100 | |
| 101 | return reset_controller_register(&rc->rst); |
| 102 | } |
| 103 | |
| 104 | static const struct of_device_id hi3660_reset_match[] = { |
| 105 | { .compatible = "hisilicon,hi3660-reset", }, |
| 106 | {}, |
| 107 | }; |
| 108 | MODULE_DEVICE_TABLE(of, hi3660_reset_match); |
| 109 | |
| 110 | static struct platform_driver hi3660_reset_driver = { |
| 111 | .probe = hi3660_reset_probe, |
| 112 | .driver = { |
| 113 | .name = "hi3660-reset", |
| 114 | .of_match_table = hi3660_reset_match, |
| 115 | }, |
| 116 | }; |
| 117 | |
| 118 | static int __init hi3660_reset_init(void) |
| 119 | { |
| 120 | return platform_driver_register(&hi3660_reset_driver); |
| 121 | } |
| 122 | arch_initcall(hi3660_reset_init); |
| 123 | |
| 124 | MODULE_LICENSE("GPL"); |
| 125 | MODULE_ALIAS("platform:hi3660-reset"); |
| 126 | MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver"); |