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/mod_devicetable.h>
 11#include <linux/module.h>
 12#include <linux/platform_data/cros_ec_commands.h>
 13#include <linux/platform_data/cros_ec_proto.h>
 14#include <linux/platform_device.h>
 15#include <linux/rtc.h>
 16
 17#define DRV_NAME "cros-usbpd-logger"
 18
 19#define CROS_USBPD_MAX_LOG_ENTRIES	30
 20#define CROS_USBPD_LOG_UPDATE_DELAY	msecs_to_jiffies(60000)
 21#define CROS_USBPD_DATA_SIZE		16
 22#define CROS_USBPD_LOG_RESP_SIZE	(sizeof(struct ec_response_pd_log) + \
 23					 CROS_USBPD_DATA_SIZE)
 24#define CROS_USBPD_BUFFER_SIZE		(sizeof(struct cros_ec_command) + \
 25					 CROS_USBPD_LOG_RESP_SIZE)
 26/* Buffer for building the PDLOG string */
 27#define BUF_SIZE	80
 28
 29struct logger_data {
 30	struct device *dev;
 31	struct cros_ec_dev *ec_dev;
 32	u8 ec_buffer[CROS_USBPD_BUFFER_SIZE];
 33	struct delayed_work log_work;
 34	struct workqueue_struct *log_workqueue;
 35};
 36
 37static const char * const chg_type_names[] = {
 38	"None", "PD", "Type-C", "Proprietary", "DCP", "CDP", "SDP",
 39	"Other", "VBUS"
 40};
 41
 42static const char * const role_names[] = {
 43	"Disconnected", "SRC", "SNK", "SNK (not charging)"
 44};
 45
 46static const char * const fault_names[] = {
 47	"---", "OCP", "fast OCP", "OVP", "Discharge"
 48};
 49
 50__printf(3, 4)
 51static int append_str(char *buf, int pos, const char *fmt, ...)
 52{
 53	va_list args;
 54	int i;
 55
 56	va_start(args, fmt);
 57	i = vsnprintf(buf + pos, BUF_SIZE - pos, fmt, args);
 58	va_end(args);
 59
 60	return i;
 61}
 62
 63static struct ec_response_pd_log *ec_get_log_entry(struct logger_data *logger)
 64{
 65	struct cros_ec_dev *ec_dev = logger->ec_dev;
 66	struct cros_ec_command *msg;
 67	int ret;
 68
 69	msg = (struct cros_ec_command *)logger->ec_buffer;
 70
 71	msg->command = ec_dev->cmd_offset + EC_CMD_PD_GET_LOG_ENTRY;
 72	msg->insize = CROS_USBPD_LOG_RESP_SIZE;
 73
 74	ret = cros_ec_cmd_xfer_status(ec_dev->ec_dev, msg);
 75	if (ret < 0)
 76		return ERR_PTR(ret);
 77
 78	return (struct ec_response_pd_log *)msg->data;
 79}
 80
 81static void cros_usbpd_print_log_entry(struct ec_response_pd_log *r,
 82				       ktime_t tstamp)
 83{
 84	const char *fault, *role, *chg_type;
 85	struct usb_chg_measures *meas;
 86	struct mcdp_info *minfo;
 87	int role_idx, type_idx;
 88	char buf[BUF_SIZE + 1];
 89	struct rtc_time rt;
 90	int len = 0;
 91	s32 rem;
 92	int i;
 93
 94	/* The timestamp is the number of 1024th of seconds in the past */
 95	tstamp = ktime_sub_us(tstamp, r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
 96	rt = rtc_ktime_to_tm(tstamp);
 97
 98	switch (r->type) {
 99	case PD_EVENT_MCU_CHARGE:
100		if (r->data & CHARGE_FLAGS_OVERRIDE)
101			len += append_str(buf, len, "override ");
102
103		if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
104			len += append_str(buf, len, "pending_override ");
105
106		role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
107		role = role_idx < ARRAY_SIZE(role_names) ?
108			role_names[role_idx] : "Unknown";
109
110		type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
111			 >> CHARGE_FLAGS_TYPE_SHIFT;
112
113		chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
114			chg_type_names[type_idx] : "???";
115
116		if (role_idx == USB_PD_PORT_POWER_DISCONNECTED ||
117		    role_idx == USB_PD_PORT_POWER_SOURCE) {
118			len += append_str(buf, len, "%s", role);
119			break;
120		}
121
122		meas = (struct usb_chg_measures *)r->payload;
123		len += append_str(buf, len, "%s %s %s %dmV max %dmV / %dmA",
124				  role,	r->data & CHARGE_FLAGS_DUAL_ROLE ?
125				  "DRP" : "Charger",
126				  chg_type, meas->voltage_now,
127				  meas->voltage_max, meas->current_max);
128		break;
129	case PD_EVENT_ACC_RW_FAIL:
130		len += append_str(buf, len, "RW signature check failed");
131		break;
132	case PD_EVENT_PS_FAULT:
133		fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
134							  : "???";
135		len += append_str(buf, len, "Power supply fault: %s", fault);
136		break;
137	case PD_EVENT_VIDEO_DP_MODE:
138		len += append_str(buf, len, "DP mode %sabled", r->data == 1 ?
139				  "en" : "dis");
140		break;
141	case PD_EVENT_VIDEO_CODEC:
142		minfo = (struct mcdp_info *)r->payload;
143		len += append_str(buf, len, "HDMI info: family:%04x chipid:%04x ",
144				  MCDP_FAMILY(minfo->family),
145				  MCDP_CHIPID(minfo->chipid));
146		len += append_str(buf, len, "irom:%d.%d.%d fw:%d.%d.%d",
147				  minfo->irom.major, minfo->irom.minor,
148				  minfo->irom.build, minfo->fw.major,
149				  minfo->fw.minor, minfo->fw.build);
150		break;
151	default:
152		len += append_str(buf, len, "Event %02x (%04x) [", r->type,
153				  r->data);
154
155		for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
156			len += append_str(buf, len, "%02x ", r->payload[i]);
157
158		len += append_str(buf, len, "]");
159		break;
160	}
161
162	div_s64_rem(ktime_to_ms(tstamp), MSEC_PER_SEC, &rem);
163	pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03d P%d %s\n",
164		rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
165		rt.tm_hour, rt.tm_min, rt.tm_sec, rem,
166		PD_LOG_PORT(r->size_port), buf);
167}
168
169static void cros_usbpd_log_check(struct work_struct *work)
170{
171	struct logger_data *logger = container_of(to_delayed_work(work),
172						  struct logger_data,
173						  log_work);
174	struct device *dev = logger->dev;
175	struct ec_response_pd_log *r;
176	int entries = 0;
177	ktime_t now;
178
179	while (entries++ < CROS_USBPD_MAX_LOG_ENTRIES) {
180		r = ec_get_log_entry(logger);
181		now = ktime_get_real();
182		if (IS_ERR(r)) {
183			dev_dbg(dev, "Cannot get PD log %ld\n", PTR_ERR(r));
184			break;
185		}
186		if (r->type == PD_EVENT_NO_ENTRY)
187			break;
188
189		cros_usbpd_print_log_entry(r, now);
190	}
191
192	queue_delayed_work(logger->log_workqueue, &logger->log_work,
193			   CROS_USBPD_LOG_UPDATE_DELAY);
194}
195
196static int cros_usbpd_logger_probe(struct platform_device *pd)
197{
198	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
199	struct device *dev = &pd->dev;
200	struct logger_data *logger;
201
202	logger = devm_kzalloc(dev, sizeof(*logger), GFP_KERNEL);
203	if (!logger)
204		return -ENOMEM;
205
206	logger->dev = dev;
207	logger->ec_dev = ec_dev;
208
209	platform_set_drvdata(pd, logger);
210
211	/* Retrieve PD event logs periodically */
212	INIT_DELAYED_WORK(&logger->log_work, cros_usbpd_log_check);
213	logger->log_workqueue =	create_singlethread_workqueue("cros_usbpd_log");
214	if (!logger->log_workqueue)
215		return -ENOMEM;
216
217	queue_delayed_work(logger->log_workqueue, &logger->log_work,
218			   CROS_USBPD_LOG_UPDATE_DELAY);
219
220	return 0;
221}
222
223static void cros_usbpd_logger_remove(struct platform_device *pd)
224{
225	struct logger_data *logger = platform_get_drvdata(pd);
226
227	cancel_delayed_work_sync(&logger->log_work);
228	destroy_workqueue(logger->log_workqueue);
229}
230
231static int __maybe_unused cros_usbpd_logger_resume(struct device *dev)
232{
233	struct logger_data *logger = dev_get_drvdata(dev);
234
235	queue_delayed_work(logger->log_workqueue, &logger->log_work,
236			   CROS_USBPD_LOG_UPDATE_DELAY);
237
238	return 0;
239}
240
241static int __maybe_unused cros_usbpd_logger_suspend(struct device *dev)
242{
243	struct logger_data *logger = dev_get_drvdata(dev);
244
245	cancel_delayed_work_sync(&logger->log_work);
246
247	return 0;
248}
249
250static SIMPLE_DEV_PM_OPS(cros_usbpd_logger_pm_ops, cros_usbpd_logger_suspend,
251			 cros_usbpd_logger_resume);
252
253static const struct platform_device_id cros_usbpd_logger_id[] = {
254	{ DRV_NAME, 0 },
255	{}
256};
257MODULE_DEVICE_TABLE(platform, cros_usbpd_logger_id);
258
259static struct platform_driver cros_usbpd_logger_driver = {
260	.driver = {
261		.name = DRV_NAME,
262		.pm = &cros_usbpd_logger_pm_ops,
263	},
264	.probe = cros_usbpd_logger_probe,
265	.remove = cros_usbpd_logger_remove,
266	.id_table = cros_usbpd_logger_id,
267};
268
269module_platform_driver(cros_usbpd_logger_driver);
270
271MODULE_LICENSE("GPL v2");
272MODULE_DESCRIPTION("Logging driver for ChromeOS EC USBPD Charger.");