| Carlo Caione | ad855ea | 2016-08-27 15:43:46 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Amlogic eFuse Driver |
| 3 | * |
| 4 | * Copyright (c) 2016 Endless Computers, Inc. |
| 5 | * Author: Carlo Caione <carlo@endlessm.com> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms of version 2 of the GNU General Public License as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 14 | * more details. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/nvmem-provider.h> |
| 19 | #include <linux/of.h> |
| 20 | #include <linux/platform_device.h> |
| 21 | |
| 22 | #include <linux/firmware/meson/meson_sm.h> |
| 23 | |
| 24 | static int meson_efuse_read(void *context, unsigned int offset, |
| 25 | void *val, size_t bytes) |
| 26 | { |
| 27 | u8 *buf = val; |
| 28 | int ret; |
| 29 | |
| 30 | ret = meson_sm_call_read(buf, SM_EFUSE_READ, offset, |
| 31 | bytes, 0, 0, 0); |
| 32 | if (ret < 0) |
| 33 | return ret; |
| 34 | |
| 35 | return 0; |
| 36 | } |
| 37 | |
| 38 | static struct nvmem_config econfig = { |
| 39 | .name = "meson-efuse", |
| 40 | .owner = THIS_MODULE, |
| 41 | .stride = 1, |
| 42 | .word_size = 1, |
| 43 | .read_only = true, |
| 44 | }; |
| 45 | |
| 46 | static const struct of_device_id meson_efuse_match[] = { |
| 47 | { .compatible = "amlogic,meson-gxbb-efuse", }, |
| 48 | { /* sentinel */ }, |
| 49 | }; |
| 50 | MODULE_DEVICE_TABLE(of, meson_efuse_match); |
| 51 | |
| 52 | static int meson_efuse_probe(struct platform_device *pdev) |
| 53 | { |
| 54 | struct nvmem_device *nvmem; |
| 55 | unsigned int size; |
| 56 | |
| 57 | if (meson_sm_call(SM_EFUSE_USER_MAX, &size, 0, 0, 0, 0, 0) < 0) |
| 58 | return -EINVAL; |
| 59 | |
| 60 | econfig.dev = &pdev->dev; |
| 61 | econfig.reg_read = meson_efuse_read; |
| 62 | econfig.size = size; |
| 63 | |
| 64 | nvmem = nvmem_register(&econfig); |
| 65 | if (IS_ERR(nvmem)) |
| 66 | return PTR_ERR(nvmem); |
| 67 | |
| 68 | platform_set_drvdata(pdev, nvmem); |
| 69 | |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | static int meson_efuse_remove(struct platform_device *pdev) |
| 74 | { |
| 75 | struct nvmem_device *nvmem = platform_get_drvdata(pdev); |
| 76 | |
| 77 | return nvmem_unregister(nvmem); |
| 78 | } |
| 79 | |
| 80 | static struct platform_driver meson_efuse_driver = { |
| 81 | .probe = meson_efuse_probe, |
| 82 | .remove = meson_efuse_remove, |
| 83 | .driver = { |
| 84 | .name = "meson-efuse", |
| 85 | .of_match_table = meson_efuse_match, |
| 86 | }, |
| 87 | }; |
| 88 | |
| 89 | module_platform_driver(meson_efuse_driver); |
| 90 | |
| 91 | MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>"); |
| 92 | MODULE_DESCRIPTION("Amlogic Meson NVMEM driver"); |
| 93 | MODULE_LICENSE("GPL v2"); |