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 #define GEN1_REASON_SHIFT 2 18 #define GEN2_REASON_SHIFT 1 19 20 #define NO_REASON_SHIFT 0 21 22 struct pm8916_pon { 23 struct device *dev; 24 struct regmap *regmap; 25 u32 baseaddr; 26 struct reboot_mode_driver reboot_mode; 27 long reason_shift; 28 }; 29 30 static int pm8916_reboot_mode_write(struct reboot_mode_driver *reboot, 31 unsigned int magic) 32 { 33 struct pm8916_pon *pon = container_of 34 (reboot, struct pm8916_pon, reboot_mode); 35 int ret; 36 37 ret = regmap_update_bits(pon->regmap, 38 pon->baseaddr + PON_SOFT_RB_SPARE, 39 GENMASK(7, pon->reason_shift), 40 magic << pon->reason_shift); 41 if (ret < 0) 42 dev_err(pon->dev, "update reboot mode bits failed\n"); 43 44 return ret; 45 } 46 47 static int pm8916_pon_probe(struct platform_device *pdev) 48 { 49 struct pm8916_pon *pon; 50 long reason_shift; 51 int error; 52 53 pon = devm_kzalloc(&pdev->dev, sizeof(*pon), GFP_KERNEL); 54 if (!pon) 55 return -ENOMEM; 56 57 pon->dev = &pdev->dev; 58 59 pon->regmap = dev_get_regmap(pdev->dev.parent, NULL); 60 if (!pon->regmap) { 61 dev_err(&pdev->dev, "failed to locate regmap\n"); 62 return -ENODEV; 63 } 64 65 error = of_property_read_u32(pdev->dev.of_node, "reg", 66 &pon->baseaddr); 67 if (error) 68 return error; 69 70 reason_shift = (long)of_device_get_match_data(&pdev->dev); 71 72 if (reason_shift != NO_REASON_SHIFT) { 73 pon->reboot_mode.dev = &pdev->dev; 74 pon->reason_shift = reason_shift; 75 pon->reboot_mode.write = pm8916_reboot_mode_write; 76 error = devm_reboot_mode_register(&pdev->dev, &pon->reboot_mode); 77 if (error) { 78 dev_err(&pdev->dev, "can't register reboot mode\n"); 79 return error; 80 } 81 } 82 83 platform_set_drvdata(pdev, pon); 84 85 return devm_of_platform_populate(&pdev->dev); 86 } 87 88 static const struct of_device_id pm8916_pon_id_table[] = { 89 { .compatible = "qcom,pm8916-pon", .data = (void *)GEN1_REASON_SHIFT }, 90 { .compatible = "qcom,pm8941-pon", .data = (void *)NO_REASON_SHIFT }, 91 { .compatible = "qcom,pms405-pon", .data = (void *)GEN1_REASON_SHIFT }, 92 { .compatible = "qcom,pm8998-pon", .data = (void *)GEN2_REASON_SHIFT }, 93 { .compatible = "qcom,pmk8350-pon", .data = (void *)GEN2_REASON_SHIFT }, 94 { } 95 }; 96 MODULE_DEVICE_TABLE(of, pm8916_pon_id_table); 97 98 static struct platform_driver pm8916_pon_driver = { 99 .probe = pm8916_pon_probe, 100 .driver = { 101 .name = "pm8916-pon", 102 .of_match_table = pm8916_pon_id_table, 103 }, 104 }; 105 module_platform_driver(pm8916_pon_driver); 106 107 MODULE_DESCRIPTION("pm8916 Power On driver"); 108 MODULE_LICENSE("GPL v2"); 109