| Laxman Dewangan | 56fb8de | 2013-12-20 18:54:00 +0530 | [diff] [blame] | 1 | /* |
| 2 | * Power off driver for ams AS3722 device. |
| 3 | * |
| 4 | * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. |
| 5 | * |
| 6 | * Author: Laxman Dewangan <ldewangan@nvidia.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms and conditions of the GNU General Public License, |
| 10 | * version 2, as published by the Free Software Foundation. |
| 11 | * |
| 12 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 13 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 14 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 15 | * more details. |
| 16 | */ |
| 17 | |
| 18 | #include <linux/mfd/as3722.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/of.h> |
| 21 | #include <linux/of_device.h> |
| 22 | #include <linux/platform_device.h> |
| 23 | #include <linux/slab.h> |
| 24 | |
| 25 | struct as3722_poweroff { |
| 26 | struct device *dev; |
| 27 | struct as3722 *as3722; |
| 28 | }; |
| 29 | |
| 30 | static struct as3722_poweroff *as3722_pm_poweroff; |
| 31 | |
| 32 | static void as3722_pm_power_off(void) |
| 33 | { |
| 34 | int ret; |
| 35 | |
| 36 | if (!as3722_pm_poweroff) { |
| 37 | pr_err("AS3722 poweroff is not initialised\n"); |
| 38 | return; |
| 39 | } |
| 40 | |
| 41 | ret = as3722_update_bits(as3722_pm_poweroff->as3722, |
| 42 | AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF); |
| 43 | if (ret < 0) |
| 44 | dev_err(as3722_pm_poweroff->dev, |
| 45 | "RESET_CONTROL_REG update failed, %d\n", ret); |
| 46 | } |
| 47 | |
| 48 | static int as3722_poweroff_probe(struct platform_device *pdev) |
| 49 | { |
| 50 | struct as3722_poweroff *as3722_poweroff; |
| 51 | struct device_node *np = pdev->dev.parent->of_node; |
| 52 | |
| 53 | if (!np) |
| 54 | return -EINVAL; |
| 55 | |
| 56 | if (!of_property_read_bool(np, "ams,system-power-controller")) |
| 57 | return 0; |
| 58 | |
| 59 | as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff), |
| 60 | GFP_KERNEL); |
| 61 | if (!as3722_poweroff) |
| 62 | return -ENOMEM; |
| 63 | |
| 64 | as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent); |
| 65 | as3722_poweroff->dev = &pdev->dev; |
| 66 | as3722_pm_poweroff = as3722_poweroff; |
| 67 | if (!pm_power_off) |
| 68 | pm_power_off = as3722_pm_power_off; |
| 69 | |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | static int as3722_poweroff_remove(struct platform_device *pdev) |
| 74 | { |
| 75 | if (pm_power_off == as3722_pm_power_off) |
| 76 | pm_power_off = NULL; |
| 77 | as3722_pm_poweroff = NULL; |
| 78 | |
| 79 | return 0; |
| 80 | } |
| 81 | |
| 82 | static struct platform_driver as3722_poweroff_driver = { |
| 83 | .driver = { |
| 84 | .name = "as3722-power-off", |
| 85 | .owner = THIS_MODULE, |
| 86 | }, |
| 87 | .probe = as3722_poweroff_probe, |
| 88 | .remove = as3722_poweroff_remove, |
| 89 | }; |
| 90 | |
| 91 | module_platform_driver(as3722_poweroff_driver); |
| 92 | |
| 93 | MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device"); |
| 94 | MODULE_ALIAS("platform:as3722-power-off"); |
| 95 | MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); |
| 96 | MODULE_LICENSE("GPL v2"); |