1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * MFD core driver for Ricoh RN5T618 PMIC
4  *
5  * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
6  * Copyright (C) 2016 Toradex AG
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/i2c.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/mfd/core.h>
14 #include <linux/mfd/rn5t618.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/reboot.h>
19 #include <linux/regmap.h>
20 
21 static const struct mfd_cell rn5t618_cells[] = {
22 	{ .name = "rn5t618-regulator" },
23 	{ .name = "rn5t618-wdt" },
24 };
25 
26 static const struct mfd_cell rc5t619_cells[] = {
27 	{ .name = "rn5t618-adc" },
28 	{ .name = "rn5t618-power" },
29 	{ .name = "rn5t618-regulator" },
30 	{ .name = "rc5t619-rtc" },
31 	{ .name = "rn5t618-wdt" },
32 };
33 
rn5t618_volatile_reg(struct device * dev,unsigned int reg)34 static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg)
35 {
36 	switch (reg) {
37 	case RN5T618_WATCHDOGCNT:
38 	case RN5T618_DCIRQ:
39 	case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL:
40 	case RN5T618_ADCCNT3:
41 	case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3:
42 	case RN5T618_IR_GPR:
43 	case RN5T618_IR_GPF:
44 	case RN5T618_MON_IOIN:
45 	case RN5T618_INTMON:
46 	case RN5T618_RTC_CTRL1 ... RN5T618_RTC_CTRL2:
47 	case RN5T618_RTC_SECONDS ... RN5T618_RTC_YEAR:
48 	case RN5T618_CHGCTL1:
49 	case RN5T618_REGISET1 ... RN5T618_REGISET2:
50 	case RN5T618_CHGSTATE:
51 	case RN5T618_CHGCTRL_IRR ... RN5T618_CHGERR_MONI:
52 	case RN5T618_GCHGDET:
53 	case RN5T618_CONTROL ... RN5T618_CC_AVEREG0:
54 		return true;
55 	default:
56 		return false;
57 	}
58 }
59 
60 static const struct regmap_config rn5t618_regmap_config = {
61 	.reg_bits	= 8,
62 	.val_bits	= 8,
63 	.volatile_reg	= rn5t618_volatile_reg,
64 	.max_register	= RN5T618_MAX_REG,
65 	.cache_type	= REGCACHE_RBTREE,
66 };
67 
68 static const struct regmap_irq rc5t619_irqs[] = {
69 	REGMAP_IRQ_REG(RN5T618_IRQ_SYS, 0, BIT(0)),
70 	REGMAP_IRQ_REG(RN5T618_IRQ_DCDC, 0, BIT(1)),
71 	REGMAP_IRQ_REG(RN5T618_IRQ_RTC, 0, BIT(2)),
72 	REGMAP_IRQ_REG(RN5T618_IRQ_ADC, 0, BIT(3)),
73 	REGMAP_IRQ_REG(RN5T618_IRQ_GPIO, 0, BIT(4)),
74 	REGMAP_IRQ_REG(RN5T618_IRQ_CHG, 0, BIT(6)),
75 };
76 
77 static const struct regmap_irq_chip rc5t619_irq_chip = {
78 	.name = "rc5t619",
79 	.irqs = rc5t619_irqs,
80 	.num_irqs = ARRAY_SIZE(rc5t619_irqs),
81 	.num_regs = 1,
82 	.status_base = RN5T618_INTMON,
83 	.unmask_base = RN5T618_INTEN,
84 };
85 
86 static struct i2c_client *rn5t618_pm_power_off;
87 static struct notifier_block rn5t618_restart_handler;
88 
rn5t618_irq_init(struct rn5t618 * rn5t618)89 static int rn5t618_irq_init(struct rn5t618 *rn5t618)
90 {
91 	const struct regmap_irq_chip *irq_chip = NULL;
92 	int ret;
93 
94 	if (!rn5t618->irq)
95 		return 0;
96 
97 	switch (rn5t618->variant) {
98 	case RC5T619:
99 		irq_chip = &rc5t619_irq_chip;
100 		break;
101 	default:
102 		dev_err(rn5t618->dev, "Currently no IRQ support for variant %d\n",
103 			(int)rn5t618->variant);
104 		return -ENOENT;
105 	}
106 
107 	ret = devm_regmap_add_irq_chip(rn5t618->dev, rn5t618->regmap,
108 				       rn5t618->irq,
109 				       IRQF_TRIGGER_LOW | IRQF_ONESHOT,
110 				       0, irq_chip, &rn5t618->irq_data);
111 	if (ret)
112 		dev_err(rn5t618->dev, "Failed to register IRQ chip\n");
113 
114 	return ret;
115 }
116 
rn5t618_trigger_poweroff_sequence(bool repower)117 static void rn5t618_trigger_poweroff_sequence(bool repower)
118 {
119 	int ret;
120 
121 	/* disable automatic repower-on */
122 	ret = i2c_smbus_read_byte_data(rn5t618_pm_power_off, RN5T618_REPCNT);
123 	if (ret < 0)
124 		goto err;
125 
126 	ret &= ~RN5T618_REPCNT_REPWRON;
127 	if (repower)
128 		ret |= RN5T618_REPCNT_REPWRON;
129 
130 	ret = i2c_smbus_write_byte_data(rn5t618_pm_power_off,
131 					RN5T618_REPCNT, (u8)ret);
132 	if (ret < 0)
133 		goto err;
134 
135 	/* start power-off sequence */
136 	ret = i2c_smbus_read_byte_data(rn5t618_pm_power_off, RN5T618_SLPCNT);
137 	if (ret < 0)
138 		goto err;
139 
140 	ret |= RN5T618_SLPCNT_SWPWROFF;
141 
142 	ret = i2c_smbus_write_byte_data(rn5t618_pm_power_off,
143 					RN5T618_SLPCNT, (u8)ret);
144 	if (ret < 0)
145 		goto err;
146 
147 	return;
148 
149 err:
150 	dev_alert(&rn5t618_pm_power_off->dev, "Failed to shutdown (err = %d)\n", ret);
151 }
152 
rn5t618_power_off(void)153 static void rn5t618_power_off(void)
154 {
155 	rn5t618_trigger_poweroff_sequence(false);
156 }
157 
rn5t618_restart(struct notifier_block * this,unsigned long mode,void * cmd)158 static int rn5t618_restart(struct notifier_block *this,
159 			    unsigned long mode, void *cmd)
160 {
161 	rn5t618_trigger_poweroff_sequence(true);
162 
163 	/*
164 	 * Re-power factor detection on PMIC side is not instant. 1ms
165 	 * proved to be enough time until reset takes effect.
166 	 */
167 	mdelay(1);
168 
169 	return NOTIFY_DONE;
170 }
171 
172 static const struct of_device_id rn5t618_of_match[] = {
173 	{ .compatible = "ricoh,rn5t567", .data = (void *)RN5T567 },
174 	{ .compatible = "ricoh,rn5t618", .data = (void *)RN5T618 },
175 	{ .compatible = "ricoh,rc5t619", .data = (void *)RC5T619 },
176 	{ }
177 };
178 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
179 
rn5t618_i2c_probe(struct i2c_client * i2c)180 static int rn5t618_i2c_probe(struct i2c_client *i2c)
181 {
182 	const struct of_device_id *of_id;
183 	struct rn5t618 *priv;
184 	int ret;
185 
186 	of_id = of_match_device(rn5t618_of_match, &i2c->dev);
187 	if (!of_id) {
188 		dev_err(&i2c->dev, "Failed to find matching DT ID\n");
189 		return -EINVAL;
190 	}
191 
192 	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
193 	if (!priv)
194 		return -ENOMEM;
195 
196 	i2c_set_clientdata(i2c, priv);
197 	priv->variant = (long)of_id->data;
198 	priv->irq = i2c->irq;
199 	priv->dev = &i2c->dev;
200 
201 	priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
202 	if (IS_ERR(priv->regmap)) {
203 		ret = PTR_ERR(priv->regmap);
204 		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
205 		return ret;
206 	}
207 
208 	if (priv->variant == RC5T619)
209 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
210 					   rc5t619_cells,
211 					   ARRAY_SIZE(rc5t619_cells),
212 					   NULL, 0, NULL);
213 	else
214 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
215 					   rn5t618_cells,
216 					   ARRAY_SIZE(rn5t618_cells),
217 					   NULL, 0, NULL);
218 	if (ret) {
219 		dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
220 		return ret;
221 	}
222 
223 	rn5t618_pm_power_off = i2c;
224 	if (of_device_is_system_power_controller(i2c->dev.of_node)) {
225 		if (!pm_power_off)
226 			pm_power_off = rn5t618_power_off;
227 		else
228 			dev_warn(&i2c->dev, "Poweroff callback already assigned\n");
229 	}
230 
231 	rn5t618_restart_handler.notifier_call = rn5t618_restart;
232 	rn5t618_restart_handler.priority = 192;
233 
234 	ret = register_restart_handler(&rn5t618_restart_handler);
235 	if (ret) {
236 		dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret);
237 		return ret;
238 	}
239 
240 	return rn5t618_irq_init(priv);
241 }
242 
rn5t618_i2c_remove(struct i2c_client * i2c)243 static void rn5t618_i2c_remove(struct i2c_client *i2c)
244 {
245 	if (i2c == rn5t618_pm_power_off) {
246 		rn5t618_pm_power_off = NULL;
247 		pm_power_off = NULL;
248 	}
249 
250 	unregister_restart_handler(&rn5t618_restart_handler);
251 }
252 
rn5t618_i2c_suspend(struct device * dev)253 static int __maybe_unused rn5t618_i2c_suspend(struct device *dev)
254 {
255 	struct rn5t618 *priv = dev_get_drvdata(dev);
256 
257 	if (priv->irq)
258 		disable_irq(priv->irq);
259 
260 	return 0;
261 }
262 
rn5t618_i2c_resume(struct device * dev)263 static int __maybe_unused rn5t618_i2c_resume(struct device *dev)
264 {
265 	struct rn5t618 *priv = dev_get_drvdata(dev);
266 
267 	if (priv->irq)
268 		enable_irq(priv->irq);
269 
270 	return 0;
271 }
272 
273 static SIMPLE_DEV_PM_OPS(rn5t618_i2c_dev_pm_ops,
274 			rn5t618_i2c_suspend,
275 			rn5t618_i2c_resume);
276 
277 static struct i2c_driver rn5t618_i2c_driver = {
278 	.driver = {
279 		.name = "rn5t618",
280 		.of_match_table = of_match_ptr(rn5t618_of_match),
281 		.pm = &rn5t618_i2c_dev_pm_ops,
282 	},
283 	.probe_new = rn5t618_i2c_probe,
284 	.remove = rn5t618_i2c_remove,
285 };
286 
287 module_i2c_driver(rn5t618_i2c_driver);
288 
289 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
290 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver");
291 MODULE_LICENSE("GPL v2");
292