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