| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Copyright (C) 2019 MediaTek Inc. |
| 4 | * Author Freddy Hsin <freddy.hsin@mediatek.com> |
| 5 | */ |
| 6 | |
| 7 | #include <linux/init.h> |
| 8 | #include <linux/module.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/of.h> |
| 11 | #include <linux/platform_device.h> |
| 12 | #include <linux/reboot.h> |
| 13 | #include <linux/regmap.h> |
| 14 | #include <linux/of_address.h> |
| 15 | #include <linux/reboot-mode.h> |
| 16 | |
| 17 | static const struct regmap_config mtk_regmap_config = { |
| 18 | .reg_bits = 32, |
| 19 | .val_bits = 32, |
| 20 | .reg_stride = 4, |
| 21 | }; |
| 22 | |
| 23 | struct mtk_reboot_mode { |
| 24 | struct regmap *map; |
| 25 | struct reboot_mode_driver reboot; |
| 26 | u32 offset; |
| 27 | u32 mask; |
| 28 | }; |
| 29 | |
| 30 | static int mtk_reboot_mode_write(struct reboot_mode_driver *reboot, |
| 31 | unsigned int magic) |
| 32 | { |
| 33 | struct mtk_reboot_mode *mtk_rbm; |
| 34 | int ret; |
| 35 | |
| 36 | mtk_rbm = container_of(reboot, struct mtk_reboot_mode, reboot); |
| 37 | |
| 38 | ret = regmap_update_bits(mtk_rbm->map, mtk_rbm->offset, |
| 39 | mtk_rbm->mask, magic); |
| 40 | if (ret < 0) |
| 41 | dev_info(reboot->dev, "update reboot mode bits failed\n"); |
| 42 | |
| 43 | return ret; |
| 44 | } |
| 45 | |
| 46 | static int mtk_regmap_lookup_by_phandle(struct device *dev, |
| 47 | struct mtk_reboot_mode *mtk_rbm) |
| 48 | { |
| 49 | struct device_node *toprgu_np; |
| 50 | struct device_node *np = dev->of_node; |
| 51 | void __iomem *base; |
| 52 | |
| 53 | toprgu_np = of_parse_phandle(np, "regmap", 0); |
| 54 | if (!toprgu_np) |
| 55 | return -EINVAL; |
| 56 | |
| 57 | if (!of_device_is_compatible(toprgu_np, "mediatek,toprgu")) |
| 58 | return -EINVAL; |
| 59 | |
| 60 | base = of_iomap(toprgu_np, 0); |
| 61 | if (IS_ERR(base)) |
| 62 | return PTR_ERR(base); |
| 63 | |
| 64 | mtk_rbm->map = devm_regmap_init_mmio(dev, base, |
| 65 | &mtk_regmap_config); |
| 66 | return PTR_ERR_OR_ZERO(mtk_rbm->map); |
| 67 | } |
| 68 | |
| 69 | static int mtk_reboot_mode_probe(struct platform_device *pdev) |
| 70 | { |
| 71 | int ret; |
| 72 | struct mtk_reboot_mode *mtk_rbm; |
| 73 | |
| 74 | mtk_rbm = devm_kzalloc(&pdev->dev, sizeof(*mtk_rbm), GFP_KERNEL); |
| 75 | if (!mtk_rbm) |
| 76 | return -ENOMEM; |
| 77 | |
| 78 | mtk_rbm->reboot.dev = &pdev->dev; |
| 79 | mtk_rbm->reboot.write = mtk_reboot_mode_write; |
| 80 | mtk_rbm->mask = 0xf; |
| 81 | |
| 82 | ret = mtk_regmap_lookup_by_phandle(&pdev->dev, mtk_rbm); |
| 83 | if (ret) { |
| 84 | dev_info(&pdev->dev, "Couldn't create the toprgu regmap\n"); |
| 85 | return -EINVAL; |
| 86 | } |
| 87 | |
| 88 | if (of_property_read_u32(pdev->dev.of_node, "offset", |
| 89 | &mtk_rbm->offset)) |
| 90 | return -EINVAL; |
| 91 | |
| 92 | of_property_read_u32(pdev->dev.of_node, "mask", &mtk_rbm->mask); |
| 93 | |
| 94 | ret = devm_reboot_mode_register(&pdev->dev, &mtk_rbm->reboot); |
| 95 | if (ret) |
| 96 | dev_info(&pdev->dev, "can't register reboot mode\n"); |
| 97 | |
| 98 | return ret; |
| 99 | } |
| 100 | |
| 101 | static const struct of_device_id mtk_reboot_mode_of_match[] = { |
| 102 | { .compatible = "toprgu-reboot-mode" }, |
| 103 | {} |
| 104 | }; |
| 105 | MODULE_DEVICE_TABLE(of, mtk_reboot_mode_of_match); |
| 106 | |
| 107 | static struct platform_driver mtk_reboot_mode_driver = { |
| 108 | .probe = mtk_reboot_mode_probe, |
| 109 | .driver = { |
| 110 | .name = "toprgu-reboot-mode", |
| 111 | .of_match_table = mtk_reboot_mode_of_match, |
| 112 | }, |
| 113 | }; |
| 114 | module_platform_driver(mtk_reboot_mode_driver); |
| 115 | |
| 116 | MODULE_AUTHOR("Freddy Hsin <freddy.hsin@mediatek.com>"); |
| 117 | MODULE_DESCRIPTION("Mediatek reboot mode driver"); |
| 118 | MODULE_LICENSE("GPL v2"); |