1 /*
2  * AXP20x PMIC USB power supply status driver
3  *
4  * Copyright (C) 2015 Hans de Goede <hdegoede@redhat.com>
5  * Copyright (C) 2014 Bruno Prémont <bonbons@linux-vserver.org>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under  the terms of the GNU General  Public License as published by the
9  * Free Software Foundation;  either version 2 of the License, or (at your
10  * option) any later version.
11  */
12 
13 #include <linux/device.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/kernel.h>
17 #include <linux/mfd/axp20x.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/platform_device.h>
21 #include <linux/power_supply.h>
22 #include <linux/regmap.h>
23 #include <linux/slab.h>
24 
25 #define DRVNAME "axp20x-usb-power-supply"
26 
27 #define AXP20X_PWR_STATUS_VBUS_PRESENT	BIT(5)
28 #define AXP20X_PWR_STATUS_VBUS_USED	BIT(4)
29 
30 #define AXP20X_USB_STATUS_VBUS_VALID	BIT(2)
31 
32 #define AXP20X_VBUS_VHOLD_uV(b)		(4000000 + (((b) >> 3) & 7) * 100000)
33 #define AXP20X_VBUS_CLIMIT_MASK		3
34 #define AXP20X_VBUC_CLIMIT_900mA	0
35 #define AXP20X_VBUC_CLIMIT_500mA	1
36 #define AXP20X_VBUC_CLIMIT_100mA	2
37 #define AXP20X_VBUC_CLIMIT_NONE		3
38 
39 #define AXP20X_ADC_EN1_VBUS_CURR	BIT(2)
40 #define AXP20X_ADC_EN1_VBUS_VOLT	BIT(3)
41 
42 #define AXP20X_VBUS_MON_VBUS_VALID	BIT(3)
43 
44 struct axp20x_usb_power {
45 	struct device_node *np;
46 	struct regmap *regmap;
47 	struct power_supply *supply;
48 };
49 
50 static irqreturn_t axp20x_usb_power_irq(int irq, void *devid)
51 {
52 	struct axp20x_usb_power *power = devid;
53 
54 	power_supply_changed(power->supply);
55 
56 	return IRQ_HANDLED;
57 }
58 
59 static int axp20x_usb_power_get_property(struct power_supply *psy,
60 	enum power_supply_property psp, union power_supply_propval *val)
61 {
62 	struct axp20x_usb_power *power = power_supply_get_drvdata(psy);
63 	unsigned int input, v;
64 	int ret;
65 
66 	switch (psp) {
67 	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
68 		ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
69 		if (ret)
70 			return ret;
71 
72 		val->intval = AXP20X_VBUS_VHOLD_uV(v);
73 		return 0;
74 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
75 		ret = axp20x_read_variable_width(power->regmap,
76 						 AXP20X_VBUS_V_ADC_H, 12);
77 		if (ret < 0)
78 			return ret;
79 
80 		val->intval = ret * 1700; /* 1 step = 1.7 mV */
81 		return 0;
82 	case POWER_SUPPLY_PROP_CURRENT_MAX:
83 		ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
84 		if (ret)
85 			return ret;
86 
87 		switch (v & AXP20X_VBUS_CLIMIT_MASK) {
88 		case AXP20X_VBUC_CLIMIT_100mA:
89 			if (of_device_is_compatible(power->np,
90 					"x-powers,axp202-usb-power-supply")) {
91 				val->intval = 100000;
92 			} else {
93 				val->intval = -1; /* No 100mA limit */
94 			}
95 			break;
96 		case AXP20X_VBUC_CLIMIT_500mA:
97 			val->intval = 500000;
98 			break;
99 		case AXP20X_VBUC_CLIMIT_900mA:
100 			val->intval = 900000;
101 			break;
102 		case AXP20X_VBUC_CLIMIT_NONE:
103 			val->intval = -1;
104 			break;
105 		}
106 		return 0;
107 	case POWER_SUPPLY_PROP_CURRENT_NOW:
108 		ret = axp20x_read_variable_width(power->regmap,
109 						 AXP20X_VBUS_I_ADC_H, 12);
110 		if (ret < 0)
111 			return ret;
112 
113 		val->intval = ret * 375; /* 1 step = 0.375 mA */
114 		return 0;
115 	default:
116 		break;
117 	}
118 
119 	/* All the properties below need the input-status reg value */
120 	ret = regmap_read(power->regmap, AXP20X_PWR_INPUT_STATUS, &input);
121 	if (ret)
122 		return ret;
123 
124 	switch (psp) {
125 	case POWER_SUPPLY_PROP_HEALTH:
126 		if (!(input & AXP20X_PWR_STATUS_VBUS_PRESENT)) {
127 			val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
128 			break;
129 		}
130 
131 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
132 
133 		if (of_device_is_compatible(power->np,
134 				"x-powers,axp202-usb-power-supply")) {
135 			ret = regmap_read(power->regmap,
136 					  AXP20X_USB_OTG_STATUS, &v);
137 			if (ret)
138 				return ret;
139 
140 			if (!(v & AXP20X_USB_STATUS_VBUS_VALID))
141 				val->intval =
142 					POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
143 		}
144 		break;
145 	case POWER_SUPPLY_PROP_PRESENT:
146 		val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_PRESENT);
147 		break;
148 	case POWER_SUPPLY_PROP_ONLINE:
149 		val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_USED);
150 		break;
151 	default:
152 		return -EINVAL;
153 	}
154 
155 	return 0;
156 }
157 
158 static enum power_supply_property axp20x_usb_power_properties[] = {
159 	POWER_SUPPLY_PROP_HEALTH,
160 	POWER_SUPPLY_PROP_PRESENT,
161 	POWER_SUPPLY_PROP_ONLINE,
162 	POWER_SUPPLY_PROP_VOLTAGE_MIN,
163 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
164 	POWER_SUPPLY_PROP_CURRENT_MAX,
165 	POWER_SUPPLY_PROP_CURRENT_NOW,
166 };
167 
168 static enum power_supply_property axp22x_usb_power_properties[] = {
169 	POWER_SUPPLY_PROP_HEALTH,
170 	POWER_SUPPLY_PROP_PRESENT,
171 	POWER_SUPPLY_PROP_ONLINE,
172 	POWER_SUPPLY_PROP_VOLTAGE_MIN,
173 	POWER_SUPPLY_PROP_CURRENT_MAX,
174 };
175 
176 static const struct power_supply_desc axp20x_usb_power_desc = {
177 	.name = "axp20x-usb",
178 	.type = POWER_SUPPLY_TYPE_USB,
179 	.properties = axp20x_usb_power_properties,
180 	.num_properties = ARRAY_SIZE(axp20x_usb_power_properties),
181 	.get_property = axp20x_usb_power_get_property,
182 };
183 
184 static const struct power_supply_desc axp22x_usb_power_desc = {
185 	.name = "axp20x-usb",
186 	.type = POWER_SUPPLY_TYPE_USB,
187 	.properties = axp22x_usb_power_properties,
188 	.num_properties = ARRAY_SIZE(axp22x_usb_power_properties),
189 	.get_property = axp20x_usb_power_get_property,
190 };
191 
192 static int axp20x_usb_power_probe(struct platform_device *pdev)
193 {
194 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
195 	struct power_supply_config psy_cfg = {};
196 	struct axp20x_usb_power *power;
197 	static const char * const axp20x_irq_names[] = { "VBUS_PLUGIN",
198 		"VBUS_REMOVAL", "VBUS_VALID", "VBUS_NOT_VALID", NULL };
199 	static const char * const axp22x_irq_names[] = {
200 		"VBUS_PLUGIN", "VBUS_REMOVAL", NULL };
201 	static const char * const *irq_names;
202 	const struct power_supply_desc *usb_power_desc;
203 	int i, irq, ret;
204 
205 	if (!of_device_is_available(pdev->dev.of_node))
206 		return -ENODEV;
207 
208 	if (!axp20x) {
209 		dev_err(&pdev->dev, "Parent drvdata not set\n");
210 		return -EINVAL;
211 	}
212 
213 	power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL);
214 	if (!power)
215 		return -ENOMEM;
216 
217 	power->np = pdev->dev.of_node;
218 	power->regmap = axp20x->regmap;
219 
220 	if (of_device_is_compatible(power->np,
221 			"x-powers,axp202-usb-power-supply")) {
222 		/* Enable vbus valid checking */
223 		ret = regmap_update_bits(power->regmap, AXP20X_VBUS_MON,
224 					 AXP20X_VBUS_MON_VBUS_VALID,
225 					 AXP20X_VBUS_MON_VBUS_VALID);
226 		if (ret)
227 			return ret;
228 
229 		/* Enable vbus voltage and current measurement */
230 		ret = regmap_update_bits(power->regmap, AXP20X_ADC_EN1,
231 			AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT,
232 			AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT);
233 		if (ret)
234 			return ret;
235 
236 		usb_power_desc = &axp20x_usb_power_desc;
237 		irq_names = axp20x_irq_names;
238 	} else if (of_device_is_compatible(power->np,
239 			"x-powers,axp221-usb-power-supply")) {
240 		usb_power_desc = &axp22x_usb_power_desc;
241 		irq_names = axp22x_irq_names;
242 	} else {
243 		dev_err(&pdev->dev, "Unsupported AXP variant: %ld\n",
244 			axp20x->variant);
245 		return -EINVAL;
246 	}
247 
248 	psy_cfg.of_node = pdev->dev.of_node;
249 	psy_cfg.drv_data = power;
250 
251 	power->supply = devm_power_supply_register(&pdev->dev, usb_power_desc,
252 						   &psy_cfg);
253 	if (IS_ERR(power->supply))
254 		return PTR_ERR(power->supply);
255 
256 	/* Request irqs after registering, as irqs may trigger immediately */
257 	for (i = 0; irq_names[i]; i++) {
258 		irq = platform_get_irq_byname(pdev, irq_names[i]);
259 		if (irq < 0) {
260 			dev_warn(&pdev->dev, "No IRQ for %s: %d\n",
261 				 irq_names[i], irq);
262 			continue;
263 		}
264 		irq = regmap_irq_get_virq(axp20x->regmap_irqc, irq);
265 		ret = devm_request_any_context_irq(&pdev->dev, irq,
266 				axp20x_usb_power_irq, 0, DRVNAME, power);
267 		if (ret < 0)
268 			dev_warn(&pdev->dev, "Error requesting %s IRQ: %d\n",
269 				 irq_names[i], ret);
270 	}
271 
272 	return 0;
273 }
274 
275 static const struct of_device_id axp20x_usb_power_match[] = {
276 	{ .compatible = "x-powers,axp202-usb-power-supply" },
277 	{ .compatible = "x-powers,axp221-usb-power-supply" },
278 	{ }
279 };
280 MODULE_DEVICE_TABLE(of, axp20x_usb_power_match);
281 
282 static struct platform_driver axp20x_usb_power_driver = {
283 	.probe = axp20x_usb_power_probe,
284 	.driver = {
285 		.name = DRVNAME,
286 		.of_match_table = axp20x_usb_power_match,
287 	},
288 };
289 
290 module_platform_driver(axp20x_usb_power_driver);
291 
292 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
293 MODULE_DESCRIPTION("AXP20x PMIC USB power supply status driver");
294 MODULE_LICENSE("GPL");
295