xref: /linux/drivers/usb/typec/ucsi/ucsi_acpi.c (revision df02351331671abb26788bc13f6d276e26ae068f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * UCSI ACPI driver
4  *
5  * Copyright (C) 2017, Intel Corporation
6  * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
7  */
8 
9 #include <linux/platform_device.h>
10 #include <linux/module.h>
11 #include <linux/acpi.h>
12 #include <linux/dmi.h>
13 
14 #include "ucsi.h"
15 
16 #define UCSI_DSM_UUID		"6f8398c2-7ca4-11e4-ad36-631042b5008f"
17 #define UCSI_DSM_FUNC_WRITE	1
18 #define UCSI_DSM_FUNC_READ	2
19 
20 struct ucsi_acpi {
21 	struct device *dev;
22 	struct ucsi *ucsi;
23 	void *base;
24 	bool check_bogus_event;
25 	guid_t guid;
26 	u64 cmd;
27 };
28 
ucsi_acpi_dsm(struct ucsi_acpi * ua,int func)29 static int ucsi_acpi_dsm(struct ucsi_acpi *ua, int func)
30 {
31 	union acpi_object *obj;
32 
33 	obj = acpi_evaluate_dsm(ACPI_HANDLE(ua->dev), &ua->guid, 1, func,
34 				NULL);
35 	if (!obj) {
36 		dev_err(ua->dev, "%s: failed to evaluate _DSM %d\n",
37 			__func__, func);
38 		return -EIO;
39 	}
40 
41 	ACPI_FREE(obj);
42 	return 0;
43 }
44 
ucsi_acpi_read_version(struct ucsi * ucsi,u16 * version)45 static int ucsi_acpi_read_version(struct ucsi *ucsi, u16 *version)
46 {
47 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
48 	int ret;
49 
50 	ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
51 	if (ret)
52 		return ret;
53 
54 	memcpy(version, ua->base + UCSI_VERSION, sizeof(*version));
55 
56 	return 0;
57 }
58 
ucsi_acpi_read_cci(struct ucsi * ucsi,u32 * cci)59 static int ucsi_acpi_read_cci(struct ucsi *ucsi, u32 *cci)
60 {
61 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
62 
63 	memcpy(cci, ua->base + UCSI_CCI, sizeof(*cci));
64 
65 	return 0;
66 }
67 
ucsi_acpi_poll_cci(struct ucsi * ucsi,u32 * cci)68 static int ucsi_acpi_poll_cci(struct ucsi *ucsi, u32 *cci)
69 {
70 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
71 	int ret;
72 
73 	ret = ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_READ);
74 	if (ret)
75 		return ret;
76 
77 	return ucsi_acpi_read_cci(ucsi, cci);
78 }
79 
ucsi_acpi_read_message_in(struct ucsi * ucsi,void * val,size_t val_len)80 static int ucsi_acpi_read_message_in(struct ucsi *ucsi, void *val, size_t val_len)
81 {
82 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
83 
84 	memcpy(val, ua->base + UCSI_MESSAGE_IN, val_len);
85 
86 	return 0;
87 }
88 
ucsi_acpi_async_control(struct ucsi * ucsi,u64 command)89 static int ucsi_acpi_async_control(struct ucsi *ucsi, u64 command)
90 {
91 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
92 
93 	memcpy(ua->base + UCSI_CONTROL, &command, sizeof(command));
94 	ua->cmd = command;
95 
96 	return ucsi_acpi_dsm(ua, UCSI_DSM_FUNC_WRITE);
97 }
98 
99 static const struct ucsi_operations ucsi_acpi_ops = {
100 	.read_version = ucsi_acpi_read_version,
101 	.read_cci = ucsi_acpi_read_cci,
102 	.poll_cci = ucsi_acpi_poll_cci,
103 	.read_message_in = ucsi_acpi_read_message_in,
104 	.sync_control = ucsi_sync_control_common,
105 	.async_control = ucsi_acpi_async_control
106 };
107 
ucsi_gram_sync_control(struct ucsi * ucsi,u64 command,u32 * cci,void * val,size_t len)108 static int ucsi_gram_sync_control(struct ucsi *ucsi, u64 command, u32 *cci,
109 				  void *val, size_t len)
110 {
111 	u16 bogus_change = UCSI_CONSTAT_POWER_LEVEL_CHANGE |
112 			   UCSI_CONSTAT_PDOS_CHANGE;
113 	struct ucsi_acpi *ua = ucsi_get_drvdata(ucsi);
114 	int ret;
115 
116 	ret = ucsi_sync_control_common(ucsi, command, cci, val, len);
117 	if (ret < 0)
118 		return ret;
119 
120 	if (UCSI_COMMAND(ua->cmd) == UCSI_GET_PDOS &&
121 	    ua->cmd & UCSI_GET_PDOS_PARTNER_PDO(1) &&
122 	    ua->cmd & UCSI_GET_PDOS_SRC_PDOS)
123 		ua->check_bogus_event = true;
124 
125 	if (UCSI_COMMAND(ua->cmd) == UCSI_GET_CONNECTOR_STATUS &&
126 	    ua->check_bogus_event) {
127 		/* Clear the bogus change */
128 		if (*(u16 *)val == bogus_change)
129 			*(u16 *)val = 0;
130 
131 		ua->check_bogus_event = false;
132 	}
133 
134 	return ret;
135 }
136 
137 static const struct ucsi_operations ucsi_gram_ops = {
138 	.read_version = ucsi_acpi_read_version,
139 	.read_cci = ucsi_acpi_read_cci,
140 	.poll_cci = ucsi_acpi_poll_cci,
141 	.read_message_in = ucsi_acpi_read_message_in,
142 	.sync_control = ucsi_gram_sync_control,
143 	.async_control = ucsi_acpi_async_control
144 };
145 
146 static const struct dmi_system_id ucsi_acpi_quirks[] = {
147 	{
148 		.matches = {
149 			DMI_MATCH(DMI_SYS_VENDOR, "LG Electronics"),
150 			DMI_MATCH(DMI_PRODUCT_FAMILY, "LG gram PC"),
151 			DMI_MATCH(DMI_PRODUCT_NAME, "90Q"),
152 		},
153 		.driver_data = (void *)&ucsi_gram_ops,
154 	},
155 	{ }
156 };
157 
ucsi_acpi_notify(acpi_handle handle,u32 event,void * data)158 static void ucsi_acpi_notify(acpi_handle handle, u32 event, void *data)
159 {
160 	struct ucsi_acpi *ua = data;
161 	u32 cci;
162 	int ret;
163 
164 	ret = ua->ucsi->ops->read_cci(ua->ucsi, &cci);
165 	if (ret)
166 		return;
167 
168 	ucsi_notify_common(ua->ucsi, cci);
169 }
170 
ucsi_acpi_probe(struct platform_device * pdev)171 static int ucsi_acpi_probe(struct platform_device *pdev)
172 {
173 	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
174 	const struct ucsi_operations *ops = &ucsi_acpi_ops;
175 	const struct dmi_system_id *id;
176 	struct ucsi_acpi *ua;
177 	struct resource *res;
178 	acpi_status status;
179 	int ret;
180 
181 	if (adev->dep_unmet)
182 		return -EPROBE_DEFER;
183 
184 	ua = devm_kzalloc(&pdev->dev, sizeof(*ua), GFP_KERNEL);
185 	if (!ua)
186 		return -ENOMEM;
187 
188 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
189 	if (!res) {
190 		dev_err(&pdev->dev, "missing memory resource\n");
191 		return -ENODEV;
192 	}
193 
194 	ua->base = devm_memremap(&pdev->dev, res->start, resource_size(res), MEMREMAP_WB);
195 	if (IS_ERR(ua->base))
196 		return PTR_ERR(ua->base);
197 
198 	ret = guid_parse(UCSI_DSM_UUID, &ua->guid);
199 	if (ret)
200 		return ret;
201 
202 	ua->dev = &pdev->dev;
203 
204 	id = dmi_first_match(ucsi_acpi_quirks);
205 	if (id)
206 		ops = id->driver_data;
207 
208 	ua->ucsi = ucsi_create(&pdev->dev, ops);
209 	if (IS_ERR(ua->ucsi))
210 		return PTR_ERR(ua->ucsi);
211 
212 	ucsi_set_drvdata(ua->ucsi, ua);
213 
214 	status = acpi_install_notify_handler(ACPI_HANDLE(&pdev->dev),
215 					     ACPI_DEVICE_NOTIFY,
216 					     ucsi_acpi_notify, ua);
217 	if (ACPI_FAILURE(status)) {
218 		dev_err(&pdev->dev, "failed to install notify handler\n");
219 		ucsi_destroy(ua->ucsi);
220 		return -ENODEV;
221 	}
222 
223 	ret = ucsi_register(ua->ucsi);
224 	if (ret) {
225 		acpi_remove_notify_handler(ACPI_HANDLE(&pdev->dev),
226 					   ACPI_DEVICE_NOTIFY,
227 					   ucsi_acpi_notify);
228 		ucsi_destroy(ua->ucsi);
229 		return ret;
230 	}
231 
232 	platform_set_drvdata(pdev, ua);
233 
234 	return 0;
235 }
236 
ucsi_acpi_remove(struct platform_device * pdev)237 static void ucsi_acpi_remove(struct platform_device *pdev)
238 {
239 	struct ucsi_acpi *ua = platform_get_drvdata(pdev);
240 
241 	ucsi_unregister(ua->ucsi);
242 	ucsi_destroy(ua->ucsi);
243 
244 	acpi_remove_notify_handler(ACPI_HANDLE(&pdev->dev), ACPI_DEVICE_NOTIFY,
245 				   ucsi_acpi_notify);
246 }
247 
ucsi_acpi_resume(struct device * dev)248 static int ucsi_acpi_resume(struct device *dev)
249 {
250 	struct ucsi_acpi *ua = dev_get_drvdata(dev);
251 
252 	return ucsi_resume(ua->ucsi);
253 }
254 
255 static DEFINE_SIMPLE_DEV_PM_OPS(ucsi_acpi_pm_ops, NULL, ucsi_acpi_resume);
256 
257 static const struct acpi_device_id ucsi_acpi_match[] = {
258 	{ "PNP0CA0", 0 },
259 	{ },
260 };
261 MODULE_DEVICE_TABLE(acpi, ucsi_acpi_match);
262 
263 static struct platform_driver ucsi_acpi_platform_driver = {
264 	.driver = {
265 		.name = "ucsi_acpi",
266 		.pm = pm_ptr(&ucsi_acpi_pm_ops),
267 		.acpi_match_table = ACPI_PTR(ucsi_acpi_match),
268 	},
269 	.probe = ucsi_acpi_probe,
270 	.remove = ucsi_acpi_remove,
271 };
272 
273 module_platform_driver(ucsi_acpi_platform_driver);
274 
275 MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
276 MODULE_LICENSE("GPL v2");
277 MODULE_DESCRIPTION("UCSI ACPI driver");
278