1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2017-18 Linaro Limited 3 4 #include <linux/delay.h> 5 #include <linux/errno.h> 6 #include <linux/kernel.h> 7 #include <linux/module.h> 8 #include <linux/of.h> 9 #include <linux/of_platform.h> 10 #include <linux/platform_device.h> 11 #include <linux/reboot.h> 12 #include <linux/reboot-mode.h> 13 #include <linux/regmap.h> 14 15 #define PON_SOFT_RB_SPARE 0x8f 16 17 struct pm8916_pon { 18 struct device *dev; 19 struct regmap *regmap; 20 u32 baseaddr; 21 struct reboot_mode_driver reboot_mode; 22 }; 23 24 static int pm8916_reboot_mode_write(struct reboot_mode_driver *reboot, 25 unsigned int magic) 26 { 27 struct pm8916_pon *pon = container_of 28 (reboot, struct pm8916_pon, reboot_mode); 29 int ret; 30 31 ret = regmap_update_bits(pon->regmap, 32 pon->baseaddr + PON_SOFT_RB_SPARE, 33 0xfc, magic << 2); 34 if (ret < 0) 35 dev_err(pon->dev, "update reboot mode bits failed\n"); 36 37 return ret; 38 } 39 40 static int pm8916_pon_probe(struct platform_device *pdev) 41 { 42 struct pm8916_pon *pon; 43 int error; 44 45 pon = devm_kzalloc(&pdev->dev, sizeof(*pon), GFP_KERNEL); 46 if (!pon) 47 return -ENOMEM; 48 49 pon->dev = &pdev->dev; 50 51 pon->regmap = dev_get_regmap(pdev->dev.parent, NULL); 52 if (!pon->regmap) { 53 dev_err(&pdev->dev, "failed to locate regmap\n"); 54 return -ENODEV; 55 } 56 57 error = of_property_read_u32(pdev->dev.of_node, "reg", 58 &pon->baseaddr); 59 if (error) 60 return error; 61 62 pon->reboot_mode.dev = &pdev->dev; 63 pon->reboot_mode.write = pm8916_reboot_mode_write; 64 error = devm_reboot_mode_register(&pdev->dev, &pon->reboot_mode); 65 if (error) { 66 dev_err(&pdev->dev, "can't register reboot mode\n"); 67 return error; 68 } 69 70 platform_set_drvdata(pdev, pon); 71 72 return devm_of_platform_populate(&pdev->dev); 73 } 74 75 static const struct of_device_id pm8916_pon_id_table[] = { 76 { .compatible = "qcom,pm8916-pon" }, 77 { .compatible = "qcom,pms405-pon" }, 78 { } 79 }; 80 MODULE_DEVICE_TABLE(of, pm8916_pon_id_table); 81 82 static struct platform_driver pm8916_pon_driver = { 83 .probe = pm8916_pon_probe, 84 .driver = { 85 .name = "pm8916-pon", 86 .of_match_table = of_match_ptr(pm8916_pon_id_table), 87 }, 88 }; 89 module_platform_driver(pm8916_pon_driver); 90 91 MODULE_DESCRIPTION("pm8916 Power On driver"); 92 MODULE_LICENSE("GPL v2"); 93