1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2013, The Linux Foundation. All rights reserved. 3 */ 4 5 #include <linux/delay.h> 6 #include <linux/err.h> 7 #include <linux/init.h> 8 #include <linux/kernel.h> 9 #include <linux/io.h> 10 #include <linux/of.h> 11 #include <linux/platform_device.h> 12 #include <linux/module.h> 13 #include <linux/reboot.h> 14 #include <linux/pm.h> 15 16 static void __iomem *msm_ps_hold; 17 static int deassert_pshold(struct notifier_block *nb, unsigned long action, 18 void *data) 19 { 20 writel(0, msm_ps_hold); 21 mdelay(10000); 22 23 return NOTIFY_DONE; 24 } 25 26 static struct notifier_block restart_nb = { 27 .notifier_call = deassert_pshold, 28 .priority = 128, 29 }; 30 31 static void do_msm_poweroff(void) 32 { 33 deassert_pshold(&restart_nb, 0, NULL); 34 } 35 36 static int msm_restart_probe(struct platform_device *pdev) 37 { 38 struct device *dev = &pdev->dev; 39 struct resource *mem; 40 41 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 42 msm_ps_hold = devm_ioremap_resource(dev, mem); 43 if (IS_ERR(msm_ps_hold)) 44 return PTR_ERR(msm_ps_hold); 45 46 register_restart_handler(&restart_nb); 47 48 pm_power_off = do_msm_poweroff; 49 50 return 0; 51 } 52 53 static const struct of_device_id of_msm_restart_match[] = { 54 { .compatible = "qcom,pshold", }, 55 {}, 56 }; 57 MODULE_DEVICE_TABLE(of, of_msm_restart_match); 58 59 static struct platform_driver msm_restart_driver = { 60 .probe = msm_restart_probe, 61 .driver = { 62 .name = "msm-restart", 63 .of_match_table = of_match_ptr(of_msm_restart_match), 64 }, 65 }; 66 67 static int __init msm_restart_init(void) 68 { 69 return platform_driver_register(&msm_restart_driver); 70 } 71 device_initcall(msm_restart_init); 72