projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 09fb07bc FK |
1 | /* |
| 2 | * Generic Syscon Reboot Driver | |
| 3 | * | |
| 4 | * Copyright (c) 2013, Applied Micro Circuits Corporation | |
| 5 | * Author: Feng Kan <fkan@apm.com> | |
| 6 | * | |
| 7 | * This program is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU General Public License as | |
| 9 | * published by the Free Software Foundation; either version 2 of | |
| 10 | * the License, or (at your option) any later version. | |
| 11 | * | |
| 12 | * This program is distributed in the hope that it will be useful, | |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 15 | * GNU General Public License for more details. | |
| 16 | */ | |
| afaebbdb | 17 | #include <linux/delay.h> |
| 09fb07bc | 18 | #include <linux/io.h> |
| 09fb07bc FK |
19 | #include <linux/notifier.h> |
| 20 | #include <linux/mfd/syscon.h> | |
| afaebbdb FK |
21 | #include <linux/of_address.h> |
| 22 | #include <linux/of_device.h> | |
| 23 | #include <linux/platform_device.h> | |
| 09fb07bc | 24 | #include <linux/reboot.h> |
| afaebbdb | 25 | #include <linux/regmap.h> |
| 09fb07bc FK |
26 | |
| 27 | struct syscon_reboot_context { | |
| 28 | struct regmap *map; | |
| 29 | u32 offset; | |
| 30 | u32 mask; | |
| 31 | struct notifier_block restart_handler; | |
| 32 | }; | |
| 33 | ||
| 09fb07bc FK |
34 | static int syscon_restart_handle(struct notifier_block *this, |
| 35 | unsigned long mode, void *cmd) | |
| 36 | { | |
| afaebbdb FK |
37 | struct syscon_reboot_context *ctx = |
| 38 | container_of(this, struct syscon_reboot_context, | |
| 39 | restart_handler); | |
| 09fb07bc FK |
40 | |
| 41 | /* Issue the reboot */ | |
| afaebbdb | 42 | regmap_write(ctx->map, ctx->offset, ctx->mask); |
| 09fb07bc | 43 | |
| afaebbdb | 44 | mdelay(1000); |
| 09fb07bc FK |
45 | |
| 46 | pr_emerg("Unable to restart system\n"); | |
| 47 | return NOTIFY_DONE; | |
| 48 | } | |
| 49 | ||
| 50 | static int syscon_reboot_probe(struct platform_device *pdev) | |
| 51 | { | |
| 52 | struct syscon_reboot_context *ctx; | |
| 53 | struct device *dev = &pdev->dev; | |
| 54 | int err; | |
| 55 | ||
| 56 | ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); | |
| 57 | if (!ctx) | |
| 58 | return -ENOMEM; | |
| 59 | ||
| 60 | ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); | |
| 61 | if (IS_ERR(ctx->map)) | |
| 62 | return PTR_ERR(ctx->map); | |
| 63 | ||
| 64 | if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset)) | |
| 65 | return -EINVAL; | |
| 66 | ||
| 67 | if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask)) | |
| 68 | return -EINVAL; | |
| 69 | ||
| 70 | ctx->restart_handler.notifier_call = syscon_restart_handle; | |
| b81180b3 | 71 | ctx->restart_handler.priority = 192; |
| 09fb07bc FK |
72 | err = register_restart_handler(&ctx->restart_handler); |
| 73 | if (err) | |
| 74 | dev_err(dev, "can't register restart notifier (err=%d)\n", err); | |
| 75 | ||
| afaebbdb | 76 | return err; |
| 09fb07bc FK |
77 | } |
| 78 | ||
| 8fb08855 | 79 | static const struct of_device_id syscon_reboot_of_match[] = { |
| 09fb07bc FK |
80 | { .compatible = "syscon-reboot" }, |
| 81 | {} | |
| 82 | }; | |
| 83 | ||
| 84 | static struct platform_driver syscon_reboot_driver = { | |
| 85 | .probe = syscon_reboot_probe, | |
| 86 | .driver = { | |
| 87 | .name = "syscon-reboot", | |
| 88 | .of_match_table = syscon_reboot_of_match, | |
| 89 | }, | |
| 90 | }; | |
| 91 | module_platform_driver(syscon_reboot_driver); |