summaryrefslogtreecommitdiff
path: root/drivers/media/platform/cros-ec-cec/cros-ec-cec.c
blob: 7bc4d8a9af287a515e13fbaae7df0b41550b2067 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
// SPDX-License-Identifier: GPL-2.0+
/*
 * CEC driver for ChromeOS Embedded Controller
 *
 * Copyright (c) 2018 BayLibre, SAS
 * Author: Neil Armstrong <narmstrong@baylibre.com>
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/dmi.h>
#include <linux/pci.h>
#include <linux/cec.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <media/cec.h>
#include <media/cec-notifier.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>

#define DRV_NAME	"cros-ec-cec"

/**
 * struct cros_ec_cec - Driver data for EC CEC
 *
 * @cros_ec: Pointer to EC device
 * @notifier: Notifier info for responding to EC events
 * @adap: CEC adapter
 * @notify: CEC notifier pointer
 * @rx_msg: storage for a received message
 */
struct cros_ec_cec {
	struct cros_ec_device *cros_ec;
	struct notifier_block notifier;
	struct cec_adapter *adap;
	struct cec_notifier *notify;
	struct cec_msg rx_msg;
};

static void handle_cec_message(struct cros_ec_cec *cros_ec_cec)
{
	struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec;
	uint8_t *cec_message = cros_ec->event_data.data.cec_message;
	unsigned int len = cros_ec->event_size;

	cros_ec_cec->rx_msg.len = len;
	memcpy(cros_ec_cec->rx_msg.msg, cec_message, len);

	cec_received_msg(cros_ec_cec->adap, &cros_ec_cec->rx_msg);
}

static void handle_cec_event(struct cros_ec_cec *cros_ec_cec)
{
	struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec;
	uint32_t events = cros_ec->event_data.data.cec_events;

	if (events & EC_MKBP_CEC_SEND_OK)
		cec_transmit_attempt_done(cros_ec_cec->adap,
					  CEC_TX_STATUS_OK);

	/* FW takes care of all retries, tell core to avoid more retries */
	if (events & EC_MKBP_CEC_SEND_FAILED)
		cec_transmit_attempt_done(cros_ec_cec->adap,
					  CEC_TX_STATUS_MAX_RETRIES |
					  CEC_TX_STATUS_NACK);
}

static int cros_ec_cec_event(struct notifier_block *nb,
			     unsigned long queued_during_suspend,
			     void *_notify)
{
	struct cros_ec_cec *cros_ec_cec;
	struct cros_ec_device *cros_ec;

	cros_ec_cec = container_of(nb, struct cros_ec_cec, notifier);
	cros_ec = cros_ec_cec->cros_ec;

	if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_EVENT) {
		handle_cec_event(cros_ec_cec);
		return NOTIFY_OK;
	}

	if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_MESSAGE) {
		handle_cec_message(cros_ec_cec);
		return NOTIFY_OK;
	}

	return NOTIFY_DONE;
}

static int cros_ec_cec_set_log_addr(struct cec_adapter *adap, u8 logical_addr)
{
	struct cros_ec_cec *cros_ec_cec = adap->priv;
	struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec;
	struct {
		struct cros_ec_command msg;
		struct ec_params_cec_set data;
	} __packed msg = {};
	int ret;

	msg.msg.command = EC_CMD_CEC_SET;
	msg.msg.outsize = sizeof(msg.data);
	msg.data.cmd = CEC_CMD_LOGICAL_ADDRESS;
	msg.data.val = logical_addr;

	ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
	if (ret < 0) {
		dev_err(cros_ec->dev,
			"error setting CEC logical address on EC: %d\n", ret);
		return ret;
	}

	return 0;
}

static int cros_ec_cec_transmit(struct cec_adapter *adap, u8 attempts,
				u32 signal_free_time, struct cec_msg *cec_msg)
{
	struct cros_ec_cec *cros_ec_cec = adap->priv;
	struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec;
	struct {
		struct cros_ec_command msg;
		struct ec_params_cec_write data;
	} __packed msg = {};
	int ret;

	msg.msg.command = EC_CMD_CEC_WRITE_MSG;
	msg.msg.outsize = cec_msg->len;
	memcpy(msg.data.msg, cec_msg->msg, cec_msg->len);

	ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
	if (ret < 0) {
		dev_err(cros_ec->dev,
			"error writing CEC msg on EC: %d\n", ret);
		return ret;
	}

	return 0;
}

static int cros_ec_cec_adap_enable(struct cec_adapter *adap, bool enable)
{
	struct cros_ec_cec *cros_ec_cec = adap->priv;
	struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec;
	struct {
		struct cros_ec_command msg;
		struct ec_params_cec_set data;
	} __packed msg = {};
	int ret;

	msg.msg.command = EC_CMD_CEC_SET;
	msg.msg.outsize = sizeof(msg.data);
	msg.data.cmd = CEC_CMD_ENABLE;
	msg.data.val = enable;

	ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
	if (ret < 0) {
		dev_err(cros_ec->dev,
			"error %sabling CEC on EC: %d\n",
			(enable ? "en" : "dis"), ret);
		return ret;
	}

	return 0;
}

static const struct cec_adap_ops cros_ec_cec_ops = {
	.adap_enable = cros_ec_cec_adap_enable,
	.adap_log_addr = cros_ec_cec_set_log_addr,
	.adap_transmit = cros_ec_cec_transmit,
};

#ifdef CONFIG_PM_SLEEP
static int cros_ec_cec_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev);

	if (device_may_wakeup(dev))
		enable_irq_wake(cros_ec_cec->cros_ec->irq);

	return 0;
}

static int cros_ec_cec_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev);

	if (device_may_wakeup(dev))
		disable_irq_wake(cros_ec_cec->cros_ec->irq);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(cros_ec_cec_pm_ops,
	cros_ec_cec_suspend, cros_ec_cec_resume);

#if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI)

/*
 * The Firmware only handles a single CEC interface tied to a single HDMI
 * connector we specify along with the DRM device name handling the HDMI output
 */

struct cec_dmi_match {
	char *sys_vendor;
	char *product_name;
	char *devname;
	char *conn;
};

static const struct cec_dmi_match cec_dmi_match_table[] = {
	/* Google Fizz */
	{ "Google", "Fizz", "0000:00:02.0", "Port B" },
};

static int cros_ec_cec_get_notifier(struct device *dev,
				    struct cec_notifier **notify)
{
	int i;

	for (i = 0 ; i < ARRAY_SIZE(cec_dmi_match_table) ; ++i) {
		const struct cec_dmi_match *m = &cec_dmi_match_table[i];

		if (dmi_match(DMI_SYS_VENDOR, m->sys_vendor) &&
		    dmi_match(DMI_PRODUCT_NAME, m->product_name)) {
			struct device *d;

			/* Find the device, bail out if not yet registered */
			d = bus_find_device_by_name(&pci_bus_type, NULL,
						    m->devname);
			if (!d)
				return -EPROBE_DEFER;

			*notify = cec_notifier_get_conn(d, m->conn);
			return 0;
		}
	}

	/* Hardware support must be added in the cec_dmi_match_table */
	dev_warn(dev, "CEC notifier not configured for this hardware\n");

	return -ENODEV;
}

#else

static int cros_ec_cec_get_notifier(struct device *dev,
				    struct cec_notifier **notify)
{
	return -ENODEV;
}

#endif

static int cros_ec_cec_probe(struct platform_device *pdev)
{
	struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent);
	struct cros_ec_device *cros_ec = ec_dev->ec_dev;
	struct cros_ec_cec *cros_ec_cec;
	int ret;

	cros_ec_cec = devm_kzalloc(&pdev->dev, sizeof(*cros_ec_cec),
				   GFP_KERNEL);
	if (!cros_ec_cec)
		return -ENOMEM;

	platform_set_drvdata(pdev, cros_ec_cec);
	cros_ec_cec->cros_ec = cros_ec;

	ret = cros_ec_cec_get_notifier(&pdev->dev, &cros_ec_cec->notify);
	if (ret)
		return ret;

	ret = device_init_wakeup(&pdev->dev, 1);
	if (ret) {
		dev_err(&pdev->dev, "failed to initialize wakeup\n");
		return ret;
	}

	cros_ec_cec->adap = cec_allocate_adapter(&cros_ec_cec_ops, cros_ec_cec,
						 DRV_NAME, CEC_CAP_DEFAULTS, 1);
	if (IS_ERR(cros_ec_cec->adap))
		return PTR_ERR(cros_ec_cec->adap);

	/* Get CEC events from the EC. */
	cros_ec_cec->notifier.notifier_call = cros_ec_cec_event;
	ret = blocking_notifier_chain_register(&cros_ec->event_notifier,
					       &cros_ec_cec->notifier);
	if (ret) {
		dev_err(&pdev->dev, "failed to register notifier\n");
		cec_delete_adapter(cros_ec_cec->adap);
		return ret;
	}

	ret = cec_register_adapter(cros_ec_cec->adap, &pdev->dev);
	if (ret < 0) {
		cec_delete_adapter(cros_ec_cec->adap);
		return ret;
	}

	cec_register_cec_notifier(cros_ec_cec->adap, cros_ec_cec->notify);

	return 0;
}

static int cros_ec_cec_remove(struct platform_device *pdev)
{
	struct cros_ec_cec *cros_ec_cec = platform_get_drvdata(pdev);
	struct device *dev = &pdev->dev;
	int ret;

	ret = blocking_notifier_chain_unregister(
			&cros_ec_cec->cros_ec->event_notifier,
			&cros_ec_cec->notifier);

	if (ret) {
		dev_err(dev, "failed to unregister notifier\n");
		return ret;
	}

	cec_unregister_adapter(cros_ec_cec->adap);

	if (cros_ec_cec->notify)
		cec_notifier_put(cros_ec_cec->notify);

	return 0;
}

static struct platform_driver cros_ec_cec_driver = {
	.probe = cros_ec_cec_probe,
	.remove  = cros_ec_cec_remove,
	.driver = {
		.name = DRV_NAME,
		.pm = &cros_ec_cec_pm_ops,
	},
};

module_platform_driver(cros_ec_cec_driver);

MODULE_DESCRIPTION("CEC driver for ChromeOS ECs");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);