1 /*
2 * Intel Cherry Trail ACPI INT33FE pseudo device driver
3 *
4 * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Some Intel Cherry Trail based device which ship with Windows 10, have
11 * this weird INT33FE ACPI device with a CRS table with 4 I2cSerialBusV2
12 * resources, for 4 different chips attached to various i2c busses:
13 * 1. The Whiskey Cove pmic, which is also described by the INT34D3 ACPI device
14 * 2. Maxim MAX17047 Fuel Gauge Controller
15 * 3. FUSB302 USB Type-C Controller
16 * 4. PI3USB30532 USB switch
17 *
18 * So this driver is a stub / pseudo driver whose only purpose is to
19 * instantiate i2c-clients for chips 2 - 4, so that standard i2c drivers
20 * for these chips can bind to the them.
21 */
22
23 #include <linux/acpi.h>
24 #include <linux/i2c.h>
25 #include <linux/interrupt.h>
26 #include <linux/module.h>
27 #include <linux/regulator/consumer.h>
28 #include <linux/slab.h>
29
30 #define EXPECTED_PTYPE 4
31
32 struct cht_int33fe_data {
33 struct i2c_client *max17047;
34 struct i2c_client *fusb302;
35 struct i2c_client *pi3usb30532;
36 /* Contain a list-head must be per device */
37 struct device_connection connections[3];
38 };
39
40 /*
41 * Grrr I severly dislike buggy BIOS-es. At least one BIOS enumerates
42 * the max17047 both through the INT33FE ACPI device (it is right there
43 * in the resources table) as well as through a separate MAX17047 device.
44 *
45 * These helpers are used to work around this by checking if an i2c-client
46 * for the max17047 has already been registered.
47 */
cht_int33fe_check_for_max17047(struct device * dev,void * data)48 static int cht_int33fe_check_for_max17047(struct device *dev, void *data)
49 {
50 struct i2c_client **max17047 = data;
51 struct acpi_device *adev;
52 const char *hid;
53
54 adev = ACPI_COMPANION(dev);
55 if (!adev)
56 return 0;
57
58 hid = acpi_device_hid(adev);
59
60 /* The MAX17047 ACPI node doesn't have an UID, so we don't check that */
61 if (strcmp(hid, "MAX17047"))
62 return 0;
63
64 *max17047 = to_i2c_client(dev);
65 return 1;
66 }
67
cht_int33fe_find_max17047(void)68 static struct i2c_client *cht_int33fe_find_max17047(void)
69 {
70 struct i2c_client *max17047 = NULL;
71
72 i2c_for_each_dev(&max17047, cht_int33fe_check_for_max17047);
73 return max17047;
74 }
75
76 static const char * const max17047_suppliers[] = { "bq24190-charger" };
77
78 static const struct property_entry max17047_props[] = {
79 PROPERTY_ENTRY_STRING_ARRAY("supplied-from", max17047_suppliers),
80 { }
81 };
82
83 static const struct property_entry fusb302_props[] = {
84 PROPERTY_ENTRY_STRING("fcs,extcon-name", "cht_wcove_pwrsrc"),
85 PROPERTY_ENTRY_U32("fcs,max-sink-microvolt", 12000000),
86 PROPERTY_ENTRY_U32("fcs,max-sink-microamp", 3000000),
87 PROPERTY_ENTRY_U32("fcs,max-sink-microwatt", 36000000),
88 { }
89 };
90
cht_int33fe_probe(struct i2c_client * client)91 static int cht_int33fe_probe(struct i2c_client *client)
92 {
93 struct device *dev = &client->dev;
94 struct i2c_board_info board_info;
95 struct cht_int33fe_data *data;
96 struct i2c_client *max17047;
97 struct regulator *regulator;
98 unsigned long long ptyp;
99 acpi_status status;
100 int fusb302_irq;
101 int ret;
102
103 status = acpi_evaluate_integer(ACPI_HANDLE(dev), "PTYP", NULL, &ptyp);
104 if (ACPI_FAILURE(status)) {
105 dev_err(dev, "Error getting PTYPE\n");
106 return -ENODEV;
107 }
108
109 /*
110 * The same ACPI HID is used for different configurations check PTYP
111 * to ensure that we are dealing with the expected config.
112 */
113 if (ptyp != EXPECTED_PTYPE)
114 return -ENODEV;
115
116 /* Check presence of INT34D3 (hardware-rev 3) expected for ptype == 4 */
117 if (!acpi_dev_present("INT34D3", "1", 3)) {
118 dev_err(dev, "Error PTYPE == %d, but no INT34D3 device\n",
119 EXPECTED_PTYPE);
120 return -ENODEV;
121 }
122
123 /*
124 * We expect the WC PMIC to be paired with a TI bq24292i charger-IC.
125 * We check for the bq24292i vbus regulator here, this has 2 purposes:
126 * 1) The bq24292i allows charging with up to 12V, setting the fusb302's
127 * max-snk voltage to 12V with another charger-IC is not good.
128 * 2) For the fusb302 driver to get the bq24292i vbus regulator, the
129 * regulator-map, which is part of the bq24292i regulator_init_data,
130 * must be registered before the fusb302 is instantiated, otherwise
131 * it will end up with a dummy-regulator.
132 * Note "cht_wc_usb_typec_vbus" comes from the regulator_init_data
133 * which is defined in i2c-cht-wc.c from where the bq24292i i2c-client
134 * gets instantiated. We use regulator_get_optional here so that we
135 * don't end up getting a dummy-regulator ourselves.
136 */
137 regulator = regulator_get_optional(dev, "cht_wc_usb_typec_vbus");
138 if (IS_ERR(regulator)) {
139 ret = PTR_ERR(regulator);
140 return (ret == -ENODEV) ? -EPROBE_DEFER : ret;
141 }
142 regulator_put(regulator);
143
144 /* The FUSB302 uses the irq at index 1 and is the only irq user */
145 fusb302_irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 1);
146 if (fusb302_irq < 0) {
147 if (fusb302_irq != -EPROBE_DEFER)
148 dev_err(dev, "Error getting FUSB302 irq\n");
149 return fusb302_irq;
150 }
151
152 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
153 if (!data)
154 return -ENOMEM;
155
156 /* Work around BIOS bug, see comment on cht_int33fe_find_max17047 */
157 max17047 = cht_int33fe_find_max17047();
158 if (max17047) {
159 /* Pre-existing i2c-client for the max17047, add device-props */
160 ret = device_add_properties(&max17047->dev, max17047_props);
161 if (ret)
162 return ret;
163 /* And re-probe to get the new device-props applied. */
164 ret = device_reprobe(&max17047->dev);
165 if (ret)
166 dev_warn(dev, "Reprobing max17047 error: %d\n", ret);
167 } else {
168 memset(&board_info, 0, sizeof(board_info));
169 strlcpy(board_info.type, "max17047", I2C_NAME_SIZE);
170 board_info.dev_name = "max17047";
171 board_info.properties = max17047_props;
172 data->max17047 = i2c_acpi_new_device(dev, 1, &board_info);
173 if (!data->max17047)
174 return -EPROBE_DEFER; /* Wait for i2c-adapter to load */
175 }
176
177 data->connections[0].endpoint[0] = "i2c-fusb302";
178 data->connections[0].endpoint[1] = "i2c-pi3usb30532";
179 data->connections[0].id = "typec-switch";
180 data->connections[1].endpoint[0] = "i2c-fusb302";
181 data->connections[1].endpoint[1] = "i2c-pi3usb30532";
182 data->connections[1].id = "typec-mux";
183 data->connections[2].endpoint[0] = "i2c-fusb302";
184 data->connections[2].endpoint[1] = "intel_xhci_usb_sw-role-switch";
185 data->connections[2].id = "usb-role-switch";
186
187 device_connection_add(&data->connections[0]);
188 device_connection_add(&data->connections[1]);
189 device_connection_add(&data->connections[2]);
190
191 memset(&board_info, 0, sizeof(board_info));
192 strlcpy(board_info.type, "typec_fusb302", I2C_NAME_SIZE);
193 board_info.dev_name = "fusb302";
194 board_info.properties = fusb302_props;
195 board_info.irq = fusb302_irq;
196
197 data->fusb302 = i2c_acpi_new_device(dev, 2, &board_info);
198 if (!data->fusb302)
199 goto out_unregister_max17047;
200
201 memset(&board_info, 0, sizeof(board_info));
202 board_info.dev_name = "pi3usb30532";
203 strlcpy(board_info.type, "pi3usb30532", I2C_NAME_SIZE);
204
205 data->pi3usb30532 = i2c_acpi_new_device(dev, 3, &board_info);
206 if (!data->pi3usb30532)
207 goto out_unregister_fusb302;
208
209 i2c_set_clientdata(client, data);
210
211 return 0;
212
213 out_unregister_fusb302:
214 i2c_unregister_device(data->fusb302);
215
216 out_unregister_max17047:
217 if (data->max17047)
218 i2c_unregister_device(data->max17047);
219
220 device_connection_remove(&data->connections[2]);
221 device_connection_remove(&data->connections[1]);
222 device_connection_remove(&data->connections[0]);
223
224 return -EPROBE_DEFER; /* Wait for the i2c-adapter to load */
225 }
226
cht_int33fe_remove(struct i2c_client * i2c)227 static int cht_int33fe_remove(struct i2c_client *i2c)
228 {
229 struct cht_int33fe_data *data = i2c_get_clientdata(i2c);
230
231 i2c_unregister_device(data->pi3usb30532);
232 i2c_unregister_device(data->fusb302);
233 if (data->max17047)
234 i2c_unregister_device(data->max17047);
235
236 device_connection_remove(&data->connections[2]);
237 device_connection_remove(&data->connections[1]);
238 device_connection_remove(&data->connections[0]);
239
240 return 0;
241 }
242
243 static const struct i2c_device_id cht_int33fe_i2c_id[] = {
244 { }
245 };
246 MODULE_DEVICE_TABLE(i2c, cht_int33fe_i2c_id);
247
248 static const struct acpi_device_id cht_int33fe_acpi_ids[] = {
249 { "INT33FE", },
250 { }
251 };
252 MODULE_DEVICE_TABLE(acpi, cht_int33fe_acpi_ids);
253
254 static struct i2c_driver cht_int33fe_driver = {
255 .driver = {
256 .name = "Intel Cherry Trail ACPI INT33FE driver",
257 .acpi_match_table = ACPI_PTR(cht_int33fe_acpi_ids),
258 },
259 .probe_new = cht_int33fe_probe,
260 .remove = cht_int33fe_remove,
261 .id_table = cht_int33fe_i2c_id,
262 .disable_i2c_core_irq_mapping = true,
263 };
264
265 module_i2c_driver(cht_int33fe_driver);
266
267 MODULE_DESCRIPTION("Intel Cherry Trail ACPI INT33FE pseudo device driver");
268 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
269 MODULE_LICENSE("GPL");
270
