1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Power off driver for ams AS3722 device. 4 * 5 * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. 6 * 7 * Author: Laxman Dewangan <ldewangan@nvidia.com> 8 */ 9 10 #include <linux/mfd/as3722.h> 11 #include <linux/module.h> 12 #include <linux/of.h> 13 #include <linux/platform_device.h> 14 #include <linux/slab.h> 15 16 struct as3722_poweroff { 17 struct device *dev; 18 struct as3722 *as3722; 19 }; 20 21 static struct as3722_poweroff *as3722_pm_poweroff; 22 23 static void as3722_pm_power_off(void) 24 { 25 int ret; 26 27 if (!as3722_pm_poweroff) { 28 pr_err("AS3722 poweroff is not initialised\n"); 29 return; 30 } 31 32 ret = as3722_update_bits(as3722_pm_poweroff->as3722, 33 AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF); 34 if (ret < 0) 35 dev_err(as3722_pm_poweroff->dev, 36 "RESET_CONTROL_REG update failed, %d\n", ret); 37 } 38 39 static int as3722_poweroff_probe(struct platform_device *pdev) 40 { 41 struct as3722_poweroff *as3722_poweroff; 42 struct device_node *np = pdev->dev.parent->of_node; 43 44 if (!np) 45 return -EINVAL; 46 47 if (!of_property_read_bool(np, "ams,system-power-controller")) 48 return 0; 49 50 as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff), 51 GFP_KERNEL); 52 if (!as3722_poweroff) 53 return -ENOMEM; 54 55 as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent); 56 as3722_poweroff->dev = &pdev->dev; 57 as3722_pm_poweroff = as3722_poweroff; 58 if (!pm_power_off) 59 pm_power_off = as3722_pm_power_off; 60 61 return 0; 62 } 63 64 static int as3722_poweroff_remove(struct platform_device *pdev) 65 { 66 if (pm_power_off == as3722_pm_power_off) 67 pm_power_off = NULL; 68 as3722_pm_poweroff = NULL; 69 70 return 0; 71 } 72 73 static struct platform_driver as3722_poweroff_driver = { 74 .driver = { 75 .name = "as3722-power-off", 76 }, 77 .probe = as3722_poweroff_probe, 78 .remove = as3722_poweroff_remove, 79 }; 80 81 module_platform_driver(as3722_poweroff_driver); 82 83 MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device"); 84 MODULE_ALIAS("platform:as3722-power-off"); 85 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 86