projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 15270587 ZG |
2 | /* |
| 3 | * Copyright (c) 2016-2017 Linaro Ltd. | |
| 4 | * Copyright (c) 2016-2017 HiSilicon Technologies Co., Ltd. | |
| 15270587 ZG |
5 | */ |
| 6 | #include <linux/kernel.h> | |
| 7 | #include <linux/mfd/syscon.h> | |
| 8 | #include <linux/module.h> | |
| 9 | #include <linux/of_device.h> | |
| 10 | #include <linux/platform_device.h> | |
| 11 | #include <linux/regmap.h> | |
| 12 | #include <linux/reset-controller.h> | |
| 13 | ||
| 14 | struct hi3660_reset_controller { | |
| 15 | struct reset_controller_dev rst; | |
| 16 | struct regmap *map; | |
| 17 | }; | |
| 18 | ||
| 19 | #define to_hi3660_reset_controller(_rst) \ | |
| 20 | container_of(_rst, struct hi3660_reset_controller, rst) | |
| 21 | ||
| 22 | static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev, | |
| 23 | unsigned long idx, bool assert) | |
| 24 | { | |
| 25 | struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev); | |
| 26 | unsigned int offset = idx >> 8; | |
| 27 | unsigned int mask = BIT(idx & 0x1f); | |
| 28 | ||
| 29 | if (assert) | |
| 30 | return regmap_write(rc->map, offset, mask); | |
| 31 | else | |
| 32 | return regmap_write(rc->map, offset + 4, mask); | |
| 33 | } | |
| 34 | ||
| 35 | static int hi3660_reset_assert(struct reset_controller_dev *rcdev, | |
| 36 | unsigned long idx) | |
| 37 | { | |
| 38 | return hi3660_reset_program_hw(rcdev, idx, true); | |
| 39 | } | |
| 40 | ||
| 41 | static int hi3660_reset_deassert(struct reset_controller_dev *rcdev, | |
| 42 | unsigned long idx) | |
| 43 | { | |
| 44 | return hi3660_reset_program_hw(rcdev, idx, false); | |
| 45 | } | |
| 46 | ||
| 47 | static int hi3660_reset_dev(struct reset_controller_dev *rcdev, | |
| 48 | unsigned long idx) | |
| 49 | { | |
| 50 | int err; | |
| 51 | ||
| 52 | err = hi3660_reset_assert(rcdev, idx); | |
| 53 | if (err) | |
| 54 | return err; | |
| 55 | ||
| 56 | return hi3660_reset_deassert(rcdev, idx); | |
| 57 | } | |
| 58 | ||
| 59 | static struct reset_control_ops hi3660_reset_ops = { | |
| 60 | .reset = hi3660_reset_dev, | |
| 61 | .assert = hi3660_reset_assert, | |
| 62 | .deassert = hi3660_reset_deassert, | |
| 63 | }; | |
| 64 | ||
| 65 | static int hi3660_reset_xlate(struct reset_controller_dev *rcdev, | |
| 66 | const struct of_phandle_args *reset_spec) | |
| 67 | { | |
| 68 | unsigned int offset, bit; | |
| 69 | ||
| 70 | offset = reset_spec->args[0]; | |
| 71 | bit = reset_spec->args[1]; | |
| 72 | ||
| 73 | return (offset << 8) | bit; | |
| 74 | } | |
| 75 | ||
| 76 | static int hi3660_reset_probe(struct platform_device *pdev) | |
| 77 | { | |
| 78 | struct hi3660_reset_controller *rc; | |
| 79 | struct device_node *np = pdev->dev.of_node; | |
| 80 | struct device *dev = &pdev->dev; | |
| 81 | ||
| 82 | rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL); | |
| 83 | if (!rc) | |
| 84 | return -ENOMEM; | |
| 85 | ||
| 86 | rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon"); | |
| 87 | if (IS_ERR(rc->map)) { | |
| 88 | dev_err(dev, "failed to get hi3660,rst-syscon\n"); | |
| 89 | return PTR_ERR(rc->map); | |
| 90 | } | |
| 91 | ||
| 92 | rc->rst.ops = &hi3660_reset_ops, | |
| 93 | rc->rst.of_node = np; | |
| 94 | rc->rst.of_reset_n_cells = 2; | |
| 95 | rc->rst.of_xlate = hi3660_reset_xlate; | |
| 96 | ||
| 97 | return reset_controller_register(&rc->rst); | |
| 98 | } | |
| 99 | ||
| 100 | static const struct of_device_id hi3660_reset_match[] = { | |
| 101 | { .compatible = "hisilicon,hi3660-reset", }, | |
| 102 | {}, | |
| 103 | }; | |
| 104 | MODULE_DEVICE_TABLE(of, hi3660_reset_match); | |
| 105 | ||
| 106 | static struct platform_driver hi3660_reset_driver = { | |
| 107 | .probe = hi3660_reset_probe, | |
| 108 | .driver = { | |
| 109 | .name = "hi3660-reset", | |
| 110 | .of_match_table = hi3660_reset_match, | |
| 111 | }, | |
| 112 | }; | |
| 113 | ||
| 114 | static int __init hi3660_reset_init(void) | |
| 115 | { | |
| 116 | return platform_driver_register(&hi3660_reset_driver); | |
| 117 | } | |
| 118 | arch_initcall(hi3660_reset_init); | |
| 119 | ||
| 120 | MODULE_LICENSE("GPL"); | |
| 121 | MODULE_ALIAS("platform:hi3660-reset"); | |
| 122 | MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver"); |