1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2023 Neil Armstrong <neil.armstrong@linaro.org>
4  */
5 #include <linux/kernel.h>
6 #include <linux/init.h>
7 #include <linux/of.h>
8 #include <linux/platform_device.h>
9 #include <linux/mfd/rk808.h>
10 #include <linux/regmap.h>
11 #include <linux/module.h>
12 #include <linux/reboot.h>
13 #include <linux/i2c.h>
14 
15 /*
16  * The Odroid Go Ultra has 2 PMICs:
17  * - RK818 (manages the battery and USB-C power supply)
18  * - RK817
19  * Both PMICs feeds power to the S922X SoC, so they must be powered-off in sequence.
20  * Vendor does power-off the RK817 first, then the RK818 so here we follow this sequence.
21  */
22 
23 struct odroid_go_ultra_poweroff_data {
24 	struct device *dev;
25 	struct device *rk817;
26 	struct device *rk818;
27 };
28 
29 static int odroid_go_ultra_poweroff_prepare(struct sys_off_data *data)
30 {
31 	struct odroid_go_ultra_poweroff_data *poweroff_data = data->cb_data;
32 	struct regmap *rk817, *rk818;
33 	int ret;
34 
35 	/* RK817 Regmap */
36 	rk817 = dev_get_regmap(poweroff_data->rk817, NULL);
37 	if (!rk817) {
38 		dev_err(poweroff_data->dev, "failed to get rk817 regmap\n");
39 		return notifier_from_errno(-EINVAL);
40 	}
41 
42 	/* RK818 Regmap */
43 	rk818 = dev_get_regmap(poweroff_data->rk818, NULL);
44 	if (!rk818) {
45 		dev_err(poweroff_data->dev, "failed to get rk818 regmap\n");
46 		return notifier_from_errno(-EINVAL);
47 	}
48 
49 	dev_info(poweroff_data->dev, "Setting PMICs for power off");
50 
51 	/* RK817 */
52 	ret = regmap_update_bits(rk817, RK817_SYS_CFG(3), DEV_OFF, DEV_OFF);
53 	if (ret) {
54 		dev_err(poweroff_data->dev, "failed to poweroff rk817\n");
55 		return notifier_from_errno(ret);
56 	}
57 
58 	/* RK818 */
59 	ret = regmap_update_bits(rk818, RK818_DEVCTRL_REG, DEV_OFF, DEV_OFF);
60 	if (ret) {
61 		dev_err(poweroff_data->dev, "failed to poweroff rk818\n");
62 		return notifier_from_errno(ret);
63 	}
64 
65 	return NOTIFY_OK;
66 }
67 
68 static void odroid_go_ultra_poweroff_put_pmic_device(void *data)
69 {
70 	struct device *dev = data;
71 
72 	put_device(dev);
73 }
74 
75 static int odroid_go_ultra_poweroff_get_pmic_device(struct device *dev, const char *compatible,
76 						    struct device **pmic)
77 {
78 	struct device_node *pmic_node;
79 	struct i2c_client *pmic_client;
80 
81 	pmic_node = of_find_compatible_node(NULL, NULL, compatible);
82 	if (!pmic_node)
83 		return -ENODEV;
84 
85 	pmic_client = of_find_i2c_device_by_node(pmic_node);
86 	of_node_put(pmic_node);
87 	if (!pmic_client)
88 		return -EPROBE_DEFER;
89 
90 	*pmic = &pmic_client->dev;
91 
92 	return devm_add_action_or_reset(dev, odroid_go_ultra_poweroff_put_pmic_device, *pmic);
93 }
94 
95 static int odroid_go_ultra_poweroff_probe(struct platform_device *pdev)
96 {
97 	struct odroid_go_ultra_poweroff_data *poweroff_data;
98 	int ret;
99 
100 	poweroff_data = devm_kzalloc(&pdev->dev, sizeof(*poweroff_data), GFP_KERNEL);
101 	if (!poweroff_data)
102 		return -ENOMEM;
103 
104 	dev_set_drvdata(&pdev->dev, poweroff_data);
105 
106 	/* RK818 PMIC Device */
107 	ret = odroid_go_ultra_poweroff_get_pmic_device(&pdev->dev, "rockchip,rk818",
108 						       &poweroff_data->rk818);
109 	if (ret)
110 		return dev_err_probe(&pdev->dev, ret, "failed to get rk818 mfd data\n");
111 
112 	/* RK817 PMIC Device */
113 	ret = odroid_go_ultra_poweroff_get_pmic_device(&pdev->dev, "rockchip,rk817",
114 						       &poweroff_data->rk817);
115 	if (ret)
116 		return dev_err_probe(&pdev->dev, ret, "failed to get rk817 mfd data\n");
117 
118 	/* Register as SYS_OFF_MODE_POWER_OFF_PREPARE because regmap_update_bits may sleep */
119 	ret = devm_register_sys_off_handler(&pdev->dev,
120 					    SYS_OFF_MODE_POWER_OFF_PREPARE,
121 					    SYS_OFF_PRIO_DEFAULT,
122 					    odroid_go_ultra_poweroff_prepare,
123 					    poweroff_data);
124 	if (ret)
125 		return dev_err_probe(&pdev->dev, ret, "failed to register sys-off handler\n");
126 
127 	dev_info(&pdev->dev, "Registered Power-Off handler\n");
128 
129 	return 0;
130 }
131 static struct platform_device *pdev;
132 
133 static struct platform_driver odroid_go_ultra_poweroff_driver = {
134 	.driver = {
135 		.name	= "odroid-go-ultra-poweroff",
136 	},
137 	.probe = odroid_go_ultra_poweroff_probe,
138 };
139 
140 static int __init odroid_go_ultra_poweroff_init(void)
141 {
142 	int ret;
143 
144 	/* Only create when running on the Odroid Go Ultra device */
145 	if (!of_device_is_compatible(of_root, "hardkernel,odroid-go-ultra"))
146 		return -ENODEV;
147 
148 	ret = platform_driver_register(&odroid_go_ultra_poweroff_driver);
149 	if (ret)
150 		return ret;
151 
152 	pdev = platform_device_register_resndata(NULL, "odroid-go-ultra-poweroff", -1,
153 						 NULL, 0, NULL, 0);
154 
155 	if (IS_ERR(pdev)) {
156 		platform_driver_unregister(&odroid_go_ultra_poweroff_driver);
157 		return PTR_ERR(pdev);
158 	}
159 
160 	return 0;
161 }
162 
163 static void __exit odroid_go_ultra_poweroff_exit(void)
164 {
165 	/* Only delete when running on the Odroid Go Ultra device */
166 	if (!of_device_is_compatible(of_root, "hardkernel,odroid-go-ultra"))
167 		return;
168 
169 	platform_device_unregister(pdev);
170 	platform_driver_unregister(&odroid_go_ultra_poweroff_driver);
171 }
172 
173 module_init(odroid_go_ultra_poweroff_init);
174 module_exit(odroid_go_ultra_poweroff_exit);
175 
176 MODULE_AUTHOR("Neil Armstrong <neil.armstrong@linaro.org>");
177 MODULE_DESCRIPTION("Odroid Go Ultra poweroff driver");
178 MODULE_LICENSE("GPL");
179