xref: /openbmc/linux/drivers/mfd/rn5t618.c (revision 95298d63)
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 		return true;
48 	default:
49 		return false;
50 	}
51 }
52 
53 static const struct regmap_config rn5t618_regmap_config = {
54 	.reg_bits	= 8,
55 	.val_bits	= 8,
56 	.volatile_reg	= rn5t618_volatile_reg,
57 	.max_register	= RN5T618_MAX_REG,
58 	.cache_type	= REGCACHE_RBTREE,
59 };
60 
61 static const struct regmap_irq rc5t619_irqs[] = {
62 	REGMAP_IRQ_REG(RN5T618_IRQ_SYS, 0, BIT(0)),
63 	REGMAP_IRQ_REG(RN5T618_IRQ_DCDC, 0, BIT(1)),
64 	REGMAP_IRQ_REG(RN5T618_IRQ_RTC, 0, BIT(2)),
65 	REGMAP_IRQ_REG(RN5T618_IRQ_ADC, 0, BIT(3)),
66 	REGMAP_IRQ_REG(RN5T618_IRQ_GPIO, 0, BIT(4)),
67 	REGMAP_IRQ_REG(RN5T618_IRQ_CHG, 0, BIT(6)),
68 };
69 
70 static const struct regmap_irq_chip rc5t619_irq_chip = {
71 	.name = "rc5t619",
72 	.irqs = rc5t619_irqs,
73 	.num_irqs = ARRAY_SIZE(rc5t619_irqs),
74 	.num_regs = 1,
75 	.status_base = RN5T618_INTMON,
76 	.mask_base = RN5T618_INTEN,
77 	.mask_invert = true,
78 };
79 
80 static struct rn5t618 *rn5t618_pm_power_off;
81 static struct notifier_block rn5t618_restart_handler;
82 
83 static int rn5t618_irq_init(struct rn5t618 *rn5t618)
84 {
85 	const struct regmap_irq_chip *irq_chip = NULL;
86 	int ret;
87 
88 	if (!rn5t618->irq)
89 		return 0;
90 
91 	switch (rn5t618->variant) {
92 	case RC5T619:
93 		irq_chip = &rc5t619_irq_chip;
94 		break;
95 	default:
96 		dev_err(rn5t618->dev, "Currently no IRQ support for variant %d\n",
97 			(int)rn5t618->variant);
98 		return -ENOENT;
99 	}
100 
101 	ret = devm_regmap_add_irq_chip(rn5t618->dev, rn5t618->regmap,
102 				       rn5t618->irq,
103 				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
104 				       0, irq_chip, &rn5t618->irq_data);
105 	if (ret)
106 		dev_err(rn5t618->dev, "Failed to register IRQ chip\n");
107 
108 	return ret;
109 }
110 
111 static void rn5t618_trigger_poweroff_sequence(bool repower)
112 {
113 	/* disable automatic repower-on */
114 	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT,
115 			   RN5T618_REPCNT_REPWRON,
116 			   repower ? RN5T618_REPCNT_REPWRON : 0);
117 	/* start power-off sequence */
118 	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT,
119 			   RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF);
120 }
121 
122 static void rn5t618_power_off(void)
123 {
124 	rn5t618_trigger_poweroff_sequence(false);
125 }
126 
127 static int rn5t618_restart(struct notifier_block *this,
128 			    unsigned long mode, void *cmd)
129 {
130 	rn5t618_trigger_poweroff_sequence(true);
131 
132 	/*
133 	 * Re-power factor detection on PMIC side is not instant. 1ms
134 	 * proved to be enough time until reset takes effect.
135 	 */
136 	mdelay(1);
137 
138 	return NOTIFY_DONE;
139 }
140 
141 static const struct of_device_id rn5t618_of_match[] = {
142 	{ .compatible = "ricoh,rn5t567", .data = (void *)RN5T567 },
143 	{ .compatible = "ricoh,rn5t618", .data = (void *)RN5T618 },
144 	{ .compatible = "ricoh,rc5t619", .data = (void *)RC5T619 },
145 	{ }
146 };
147 MODULE_DEVICE_TABLE(of, rn5t618_of_match);
148 
149 static int rn5t618_i2c_probe(struct i2c_client *i2c)
150 {
151 	const struct of_device_id *of_id;
152 	struct rn5t618 *priv;
153 	int ret;
154 
155 	of_id = of_match_device(rn5t618_of_match, &i2c->dev);
156 	if (!of_id) {
157 		dev_err(&i2c->dev, "Failed to find matching DT ID\n");
158 		return -EINVAL;
159 	}
160 
161 	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
162 	if (!priv)
163 		return -ENOMEM;
164 
165 	i2c_set_clientdata(i2c, priv);
166 	priv->variant = (long)of_id->data;
167 	priv->irq = i2c->irq;
168 	priv->dev = &i2c->dev;
169 
170 	priv->regmap = devm_regmap_init_i2c(i2c, &rn5t618_regmap_config);
171 	if (IS_ERR(priv->regmap)) {
172 		ret = PTR_ERR(priv->regmap);
173 		dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
174 		return ret;
175 	}
176 
177 	if (priv->variant == RC5T619)
178 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
179 					   rc5t619_cells,
180 					   ARRAY_SIZE(rc5t619_cells),
181 					   NULL, 0, NULL);
182 	else
183 		ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_NONE,
184 					   rn5t618_cells,
185 					   ARRAY_SIZE(rn5t618_cells),
186 					   NULL, 0, NULL);
187 	if (ret) {
188 		dev_err(&i2c->dev, "failed to add sub-devices: %d\n", ret);
189 		return ret;
190 	}
191 
192 	rn5t618_pm_power_off = priv;
193 	if (of_device_is_system_power_controller(i2c->dev.of_node)) {
194 		if (!pm_power_off)
195 			pm_power_off = rn5t618_power_off;
196 		else
197 			dev_warn(&i2c->dev, "Poweroff callback already assigned\n");
198 	}
199 
200 	rn5t618_restart_handler.notifier_call = rn5t618_restart;
201 	rn5t618_restart_handler.priority = 192;
202 
203 	ret = register_restart_handler(&rn5t618_restart_handler);
204 	if (ret) {
205 		dev_err(&i2c->dev, "cannot register restart handler, %d\n", ret);
206 		return ret;
207 	}
208 
209 	return rn5t618_irq_init(priv);
210 }
211 
212 static int rn5t618_i2c_remove(struct i2c_client *i2c)
213 {
214 	struct rn5t618 *priv = i2c_get_clientdata(i2c);
215 
216 	if (priv == rn5t618_pm_power_off) {
217 		rn5t618_pm_power_off = NULL;
218 		pm_power_off = NULL;
219 	}
220 
221 	unregister_restart_handler(&rn5t618_restart_handler);
222 
223 	return 0;
224 }
225 
226 static int __maybe_unused rn5t618_i2c_suspend(struct device *dev)
227 {
228 	struct rn5t618 *priv = dev_get_drvdata(dev);
229 
230 	if (priv->irq)
231 		disable_irq(priv->irq);
232 
233 	return 0;
234 }
235 
236 static int __maybe_unused rn5t618_i2c_resume(struct device *dev)
237 {
238 	struct rn5t618 *priv = dev_get_drvdata(dev);
239 
240 	if (priv->irq)
241 		enable_irq(priv->irq);
242 
243 	return 0;
244 }
245 
246 static SIMPLE_DEV_PM_OPS(rn5t618_i2c_dev_pm_ops,
247 			rn5t618_i2c_suspend,
248 			rn5t618_i2c_resume);
249 
250 static struct i2c_driver rn5t618_i2c_driver = {
251 	.driver = {
252 		.name = "rn5t618",
253 		.of_match_table = of_match_ptr(rn5t618_of_match),
254 		.pm = &rn5t618_i2c_dev_pm_ops,
255 	},
256 	.probe_new = rn5t618_i2c_probe,
257 	.remove = rn5t618_i2c_remove,
258 };
259 
260 module_i2c_driver(rn5t618_i2c_driver);
261 
262 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
263 MODULE_DESCRIPTION("Ricoh RN5T567/618 MFD driver");
264 MODULE_LICENSE("GPL v2");
265