1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Logging driver for ChromeOS EC based USBPD Charger.
4  *
5  * Copyright 2018 Google LLC.
6  */
7 
8 #include <linux/ktime.h>
9 #include <linux/math64.h>
10 #include <linux/module.h>
11 #include <linux/platform_data/cros_ec_commands.h>
12 #include <linux/platform_data/cros_ec_proto.h>
13 #include <linux/platform_device.h>
14 #include <linux/rtc.h>
15 
16 #define DRV_NAME "cros-usbpd-logger"
17 
18 #define CROS_USBPD_MAX_LOG_ENTRIES	30
19 #define CROS_USBPD_LOG_UPDATE_DELAY	msecs_to_jiffies(60000)
20 #define CROS_USBPD_DATA_SIZE		16
21 #define CROS_USBPD_LOG_RESP_SIZE	(sizeof(struct ec_response_pd_log) + \
22 					 CROS_USBPD_DATA_SIZE)
23 #define CROS_USBPD_BUFFER_SIZE		(sizeof(struct cros_ec_command) + \
24 					 CROS_USBPD_LOG_RESP_SIZE)
25 /* Buffer for building the PDLOG string */
26 #define BUF_SIZE	80
27 
28 struct logger_data {
29 	struct device *dev;
30 	struct cros_ec_dev *ec_dev;
31 	u8 ec_buffer[CROS_USBPD_BUFFER_SIZE];
32 	struct delayed_work log_work;
33 	struct workqueue_struct *log_workqueue;
34 };
35 
36 static const char * const chg_type_names[] = {
37 	"None", "PD", "Type-C", "Proprietary", "DCP", "CDP", "SDP",
38 	"Other", "VBUS"
39 };
40 
41 static const char * const role_names[] = {
42 	"Disconnected", "SRC", "SNK", "SNK (not charging)"
43 };
44 
45 static const char * const fault_names[] = {
46 	"---", "OCP", "fast OCP", "OVP", "Discharge"
47 };
48 
49 __printf(3, 4)
50 static int append_str(char *buf, int pos, const char *fmt, ...)
51 {
52 	va_list args;
53 	int i;
54 
55 	va_start(args, fmt);
56 	i = vsnprintf(buf + pos, BUF_SIZE - pos, fmt, args);
57 	va_end(args);
58 
59 	return i;
60 }
61 
62 static struct ec_response_pd_log *ec_get_log_entry(struct logger_data *logger)
63 {
64 	struct cros_ec_dev *ec_dev = logger->ec_dev;
65 	struct cros_ec_command *msg;
66 	int ret;
67 
68 	msg = (struct cros_ec_command *)logger->ec_buffer;
69 
70 	msg->command = ec_dev->cmd_offset + EC_CMD_PD_GET_LOG_ENTRY;
71 	msg->insize = CROS_USBPD_LOG_RESP_SIZE;
72 
73 	ret = cros_ec_cmd_xfer_status(ec_dev->ec_dev, msg);
74 	if (ret < 0)
75 		return ERR_PTR(ret);
76 
77 	return (struct ec_response_pd_log *)msg->data;
78 }
79 
80 static void cros_usbpd_print_log_entry(struct ec_response_pd_log *r,
81 				       ktime_t tstamp)
82 {
83 	const char *fault, *role, *chg_type;
84 	struct usb_chg_measures *meas;
85 	struct mcdp_info *minfo;
86 	int role_idx, type_idx;
87 	char buf[BUF_SIZE + 1];
88 	struct rtc_time rt;
89 	int len = 0;
90 	s32 rem;
91 	int i;
92 
93 	/* The timestamp is the number of 1024th of seconds in the past */
94 	tstamp = ktime_sub_us(tstamp, r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
95 	rt = rtc_ktime_to_tm(tstamp);
96 
97 	switch (r->type) {
98 	case PD_EVENT_MCU_CHARGE:
99 		if (r->data & CHARGE_FLAGS_OVERRIDE)
100 			len += append_str(buf, len, "override ");
101 
102 		if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
103 			len += append_str(buf, len, "pending_override ");
104 
105 		role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
106 		role = role_idx < ARRAY_SIZE(role_names) ?
107 			role_names[role_idx] : "Unknown";
108 
109 		type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
110 			 >> CHARGE_FLAGS_TYPE_SHIFT;
111 
112 		chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
113 			chg_type_names[type_idx] : "???";
114 
115 		if (role_idx == USB_PD_PORT_POWER_DISCONNECTED ||
116 		    role_idx == USB_PD_PORT_POWER_SOURCE) {
117 			len += append_str(buf, len, "%s", role);
118 			break;
119 		}
120 
121 		meas = (struct usb_chg_measures *)r->payload;
122 		len += append_str(buf, len, "%s %s %s %dmV max %dmV / %dmA",
123 				  role,	r->data & CHARGE_FLAGS_DUAL_ROLE ?
124 				  "DRP" : "Charger",
125 				  chg_type, meas->voltage_now,
126 				  meas->voltage_max, meas->current_max);
127 		break;
128 	case PD_EVENT_ACC_RW_FAIL:
129 		len += append_str(buf, len, "RW signature check failed");
130 		break;
131 	case PD_EVENT_PS_FAULT:
132 		fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
133 							  : "???";
134 		len += append_str(buf, len, "Power supply fault: %s", fault);
135 		break;
136 	case PD_EVENT_VIDEO_DP_MODE:
137 		len += append_str(buf, len, "DP mode %sabled", r->data == 1 ?
138 				  "en" : "dis");
139 		break;
140 	case PD_EVENT_VIDEO_CODEC:
141 		minfo = (struct mcdp_info *)r->payload;
142 		len += append_str(buf, len, "HDMI info: family:%04x chipid:%04x ",
143 				  MCDP_FAMILY(minfo->family),
144 				  MCDP_CHIPID(minfo->chipid));
145 		len += append_str(buf, len, "irom:%d.%d.%d fw:%d.%d.%d",
146 				  minfo->irom.major, minfo->irom.minor,
147 				  minfo->irom.build, minfo->fw.major,
148 				  minfo->fw.minor, minfo->fw.build);
149 		break;
150 	default:
151 		len += append_str(buf, len, "Event %02x (%04x) [", r->type,
152 				  r->data);
153 
154 		for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
155 			len += append_str(buf, len, "%02x ", r->payload[i]);
156 
157 		len += append_str(buf, len, "]");
158 		break;
159 	}
160 
161 	div_s64_rem(ktime_to_ms(tstamp), MSEC_PER_SEC, &rem);
162 	pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03d P%d %s\n",
163 		rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
164 		rt.tm_hour, rt.tm_min, rt.tm_sec, rem,
165 		PD_LOG_PORT(r->size_port), buf);
166 }
167 
168 static void cros_usbpd_log_check(struct work_struct *work)
169 {
170 	struct logger_data *logger = container_of(to_delayed_work(work),
171 						  struct logger_data,
172 						  log_work);
173 	struct device *dev = logger->dev;
174 	struct ec_response_pd_log *r;
175 	int entries = 0;
176 	ktime_t now;
177 
178 	while (entries++ < CROS_USBPD_MAX_LOG_ENTRIES) {
179 		r = ec_get_log_entry(logger);
180 		now = ktime_get_real();
181 		if (IS_ERR(r)) {
182 			dev_dbg(dev, "Cannot get PD log %ld\n", PTR_ERR(r));
183 			break;
184 		}
185 		if (r->type == PD_EVENT_NO_ENTRY)
186 			break;
187 
188 		cros_usbpd_print_log_entry(r, now);
189 	}
190 
191 	queue_delayed_work(logger->log_workqueue, &logger->log_work,
192 			   CROS_USBPD_LOG_UPDATE_DELAY);
193 }
194 
195 static int cros_usbpd_logger_probe(struct platform_device *pd)
196 {
197 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
198 	struct device *dev = &pd->dev;
199 	struct logger_data *logger;
200 
201 	logger = devm_kzalloc(dev, sizeof(*logger), GFP_KERNEL);
202 	if (!logger)
203 		return -ENOMEM;
204 
205 	logger->dev = dev;
206 	logger->ec_dev = ec_dev;
207 
208 	platform_set_drvdata(pd, logger);
209 
210 	/* Retrieve PD event logs periodically */
211 	INIT_DELAYED_WORK(&logger->log_work, cros_usbpd_log_check);
212 	logger->log_workqueue =	create_singlethread_workqueue("cros_usbpd_log");
213 	if (!logger->log_workqueue)
214 		return -ENOMEM;
215 
216 	queue_delayed_work(logger->log_workqueue, &logger->log_work,
217 			   CROS_USBPD_LOG_UPDATE_DELAY);
218 
219 	return 0;
220 }
221 
222 static int cros_usbpd_logger_remove(struct platform_device *pd)
223 {
224 	struct logger_data *logger = platform_get_drvdata(pd);
225 
226 	cancel_delayed_work_sync(&logger->log_work);
227 	destroy_workqueue(logger->log_workqueue);
228 
229 	return 0;
230 }
231 
232 static int __maybe_unused cros_usbpd_logger_resume(struct device *dev)
233 {
234 	struct logger_data *logger = dev_get_drvdata(dev);
235 
236 	queue_delayed_work(logger->log_workqueue, &logger->log_work,
237 			   CROS_USBPD_LOG_UPDATE_DELAY);
238 
239 	return 0;
240 }
241 
242 static int __maybe_unused cros_usbpd_logger_suspend(struct device *dev)
243 {
244 	struct logger_data *logger = dev_get_drvdata(dev);
245 
246 	cancel_delayed_work_sync(&logger->log_work);
247 
248 	return 0;
249 }
250 
251 static SIMPLE_DEV_PM_OPS(cros_usbpd_logger_pm_ops, cros_usbpd_logger_suspend,
252 			 cros_usbpd_logger_resume);
253 
254 static struct platform_driver cros_usbpd_logger_driver = {
255 	.driver = {
256 		.name = DRV_NAME,
257 		.pm = &cros_usbpd_logger_pm_ops,
258 	},
259 	.probe = cros_usbpd_logger_probe,
260 	.remove = cros_usbpd_logger_remove,
261 };
262 
263 module_platform_driver(cros_usbpd_logger_driver);
264 
265 MODULE_LICENSE("GPL v2");
266 MODULE_DESCRIPTION("Logging driver for ChromeOS EC USBPD Charger.");
267 MODULE_ALIAS("platform:" DRV_NAME);
268