xref: /openbmc/linux/drivers/mfd/rn5t618.c (revision f97769fd)
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-regulator" },
29 	{ .name = "rc5t619-rtc" },
30 	{ .name = "rn5t618-wdt" },
31 };
32 
33 static bool rn5t618_volatile_reg(struct device *dev, unsigned int reg)
34 {
35 	switch (reg) {
36 	case RN5T618_WATCHDOGCNT:
37 	case RN5T618_DCIRQ:
38 	case RN5T618_ILIMDATAH ... RN5T618_AIN0DATAL:
39 	case RN5T618_ADCCNT3:
40 	case RN5T618_IR_ADC1 ... RN5T618_IR_ADC3:
41 	case RN5T618_IR_GPR:
42 	case RN5T618_IR_GPF:
43 	case RN5T618_MON_IOIN:
44 	case RN5T618_INTMON:
45 	case RN5T618_RTC_CTRL1 ... RN5T618_RTC_CTRL2:
46 	case RN5T618_RTC_SECONDS ... RN5T618_RTC_YEAR:
47 	case RN5T618_CHGSTATE:
48 	case RN5T618_CHGCTRL_IRR ... RN5T618_CHGERR_MONI:
49 	case RN5T618_CONTROL ... RN5T618_CC_AVEREG0:
50 		return true;
51 	default:
52 		return false;
53 	}
54 }
55 
56 static const struct regmap_config rn5t618_regmap_config = {
57 	.reg_bits	= 8,
58 	.val_bits	= 8,
59 	.volatile_reg	= rn5t618_volatile_reg,
60 	.max_register	= RN5T618_MAX_REG,
61 	.cache_type	= REGCACHE_RBTREE,
62 };
63 
64 static const struct regmap_irq rc5t619_irqs[] = {
65 	REGMAP_IRQ_REG(RN5T618_IRQ_SYS, 0, BIT(0)),
66 	REGMAP_IRQ_REG(RN5T618_IRQ_DCDC, 0, BIT(1)),
67 	REGMAP_IRQ_REG(RN5T618_IRQ_RTC, 0, BIT(2)),
68 	REGMAP_IRQ_REG(RN5T618_IRQ_ADC, 0, BIT(3)),
69 	REGMAP_IRQ_REG(RN5T618_IRQ_GPIO, 0, BIT(4)),
70 	REGMAP_IRQ_REG(RN5T618_IRQ_CHG, 0, BIT(6)),
71 };
72 
73 static const struct regmap_irq_chip rc5t619_irq_chip = {
74 	.name = "rc5t619",
75 	.irqs = rc5t619_irqs,
76 	.num_irqs = ARRAY_SIZE(rc5t619_irqs),
77 	.num_regs = 1,
78 	.status_base = RN5T618_INTMON,
79 	.mask_base = RN5T618_INTEN,
80 	.mask_invert = true,
81 };
82 
83 static struct i2c_client *rn5t618_pm_power_off;
84 static struct notifier_block rn5t618_restart_handler;
85 
86 static int rn5t618_irq_init(struct rn5t618 *rn5t618)
87 {
88 	const struct regmap_irq_chip *irq_chip = NULL;
89 	int ret;
90 
91 	if (!rn5t618->irq)
92 		return 0;
93 
94 	switch (rn5t618->variant) {
95 	case RC5T619:
96 		irq_chip = &rc5t619_irq_chip;
97 		break;
98 	default:
99 		dev_err(rn5t618->dev, "Currently no IRQ support for variant %d\n",
100 			(int)rn5t618->variant);
101 		return -ENOENT;
102 	}
103 
104 	ret = devm_regmap_add_irq_chip(rn5t618->dev, rn5t618->regmap,
105 				       rn5t618->irq,
106 				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
107 				       0, irq_chip, &rn5t618->irq_data);
108 	if (ret)
109 		dev_err(rn5t618->dev, "Failed to register IRQ chip\n");
110 
111 	return ret;
112 }
113 
114 static void rn5t618_trigger_poweroff_sequence(bool repower)
115 {
116 	int ret;
117 
118 	/* disable automatic repower-on */
119 	ret = i2c_smbus_read_byte_data(rn5t618_pm_power_off, RN5T618_REPCNT);
120 	if (ret < 0)
121 		goto err;
122 
123 	ret &= ~RN5T618_REPCNT_REPWRON;
124 	if (repower)
125 		ret |= RN5T618_REPCNT_REPWRON;
126 
127 	ret = i2c_smbus_write_byte_data(rn5t618_pm_power_off,
128 					RN5T618_REPCNT, (u8)ret);
129 	if (ret < 0)
130 		goto err;
131 
132 	/* start power-off sequence */
133 	ret = i2c_smbus_read_byte_data(rn5t618_pm_power_off, RN5T618_SLPCNT);
134 	if (ret < 0)
135 		goto err;
136 
137 	ret |= RN5T618_SLPCNT_SWPWROFF;
138 
139 	ret = i2c_smbus_write_byte_data(rn5t618_pm_power_off,
140 					RN5T618_SLPCNT, (u8)ret);
141 	if (ret < 0)
142 		goto err;
143 
144 	return;
145 
146 err:
147 	dev_alert(&rn5t618_pm_power_off->dev, "Failed to shutdown (err = %d)\n", ret);
148 }
149 
150 static void rn5t618_power_off(void)
151 {
152 	rn5t618_trigger_poweroff_sequence(false);
153 }
154 
155 static int rn5t618_restart(struct notifier_block *this,
156 			    unsigned long mode, void *cmd)
157 {
158 	rn5t618_trigger_poweroff_sequence(true);
159 
160 	/*
161 	 * Re-power factor detection on PMIC side is not instant. 1ms
162 	 * proved to be enough time until reset takes effect.
163 	 */
164 	mdelay(1);
165 
166 	return NOTIFY_DONE;
167 }
168 
169 static const struct of_device_id rn5t618_of_match[] = {
170 	{ .compatible = "ricoh,rn5t567", .data = (void *)RN5T567 },
171 	{ .compatible = "ricoh,rn5t618", .data = (void *)RN5T618 },
172 	{ .compatible = "ricoh,rc5t619", .data = (void *)RC5T619 },
173 	{ }
174 };
175 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
176 
177 static int rn5t618_i2c_probe(struct i2c_client *i2c)
178 {
179 	const struct of_device_id *of_id;
180 	struct rn5t618 *priv;
181 	int ret;
182 
183 	of_id = of_match_device(rn5t618_of_match, &i2c->dev);
184 	if (!of_id) {
185 		dev_err(&i2c->dev, "Failed to find matching DT ID\n");
186 		return -EINVAL;
187 	}
188 
189 	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
190 	if (!priv)
191 		return -ENOMEM;
192 
193 	i2c_set_clientdata(i2c, priv);
194 	priv->variant = (long)of_id->data;
195 	priv->irq = i2c->irq;
196 	priv->dev = &i2c->dev;
197 
198 	priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
199 	if (IS_ERR(priv->regmap)) {
200 		ret = PTR_ERR(priv->regmap);
201 		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
202 		return ret;
203 	}
204 
205 	if (priv->variant == RC5T619)
206 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
207 					   rc5t619_cells,
208 					   ARRAY_SIZE(rc5t619_cells),
209 					   NULL, 0, NULL);
210 	else
211 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
212 					   rn5t618_cells,
213 					   ARRAY_SIZE(rn5t618_cells),
214 					   NULL, 0, NULL);
215 	if (ret) {
216 		dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
217 		return ret;
218 	}
219 
220 	rn5t618_pm_power_off = i2c;
221 	if (of_device_is_system_power_controller(i2c->dev.of_node)) {
222 		if (!pm_power_off)
223 			pm_power_off = rn5t618_power_off;
224 		else
225 			dev_warn(&i2c->dev, "Poweroff callback already assigned\n");
226 	}
227 
228 	rn5t618_restart_handler.notifier_call = rn5t618_restart;
229 	rn5t618_restart_handler.priority = 192;
230 
231 	ret = register_restart_handler(&rn5t618_restart_handler);
232 	if (ret) {
233 		dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret);
234 		return ret;
235 	}
236 
237 	return rn5t618_irq_init(priv);
238 }
239 
240 static int rn5t618_i2c_remove(struct i2c_client *i2c)
241 {
242 	if (i2c == rn5t618_pm_power_off) {
243 		rn5t618_pm_power_off = NULL;
244 		pm_power_off = NULL;
245 	}
246 
247 	unregister_restart_handler(&rn5t618_restart_handler);
248 
249 	return 0;
250 }
251 
252 static int __maybe_unused rn5t618_i2c_suspend(struct device *dev)
253 {
254 	struct rn5t618 *priv = dev_get_drvdata(dev);
255 
256 	if (priv->irq)
257 		disable_irq(priv->irq);
258 
259 	return 0;
260 }
261 
262 static int __maybe_unused rn5t618_i2c_resume(struct device *dev)
263 {
264 	struct rn5t618 *priv = dev_get_drvdata(dev);
265 
266 	if (priv->irq)
267 		enable_irq(priv->irq);
268 
269 	return 0;
270 }
271 
272 static SIMPLE_DEV_PM_OPS(rn5t618_i2c_dev_pm_ops,
273 			rn5t618_i2c_suspend,
274 			rn5t618_i2c_resume);
275 
276 static struct i2c_driver rn5t618_i2c_driver = {
277 	.driver = {
278 		.name = "rn5t618",
279 		.of_match_table = of_match_ptr(rn5t618_of_match),
280 		.pm = &rn5t618_i2c_dev_pm_ops,
281 	},
282 	.probe_new = rn5t618_i2c_probe,
283 	.remove = rn5t618_i2c_remove,
284 };
285 
286 module_i2c_driver(rn5t618_i2c_driver);
287 
288 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
289 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver");
290 MODULE_LICENSE("GPL v2");
291