odroid-go-ultra-poweroff.c

  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
 23struct odroid_go_ultra_poweroff_data {
 24	struct device *dev;
 25	struct device *rk817;
 26	struct device *rk818;
 27};
 28
 29static 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
 68static void odroid_go_ultra_poweroff_put_pmic_device(void *data)
 69{
 70	struct device *dev = data;
 71
 72	put_device(dev);
 73}
 74
 75static 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
 95static 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}
131static struct platform_device *pdev;
132
133static 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
140static 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
163static 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
173module_init(odroid_go_ultra_poweroff_init);
174module_exit(odroid_go_ultra_poweroff_exit);
175
176MODULE_AUTHOR("Neil Armstrong <neil.armstrong@linaro.org>");
177MODULE_DESCRIPTION("Odroid Go Ultra poweroff driver");
178MODULE_LICENSE("GPL");