--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Logging driver for ChromeOS EC based USBPD Charger.
+ *
+ * Copyright 2018 Google LLC.
+ */
+
+#include <linux/ktime.h>
+#include <linux/math64.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+#define DRV_NAME "cros-usbpd-logger"
+
+#define CROS_USBPD_MAX_LOG_ENTRIES 30
+#define CROS_USBPD_LOG_UPDATE_DELAY msecs_to_jiffies(60000)
+#define CROS_USBPD_DATA_SIZE 16
+#define CROS_USBPD_LOG_RESP_SIZE (sizeof(struct ec_response_pd_log) + \
+ CROS_USBPD_DATA_SIZE)
+#define CROS_USBPD_BUFFER_SIZE (sizeof(struct cros_ec_command) + \
+ CROS_USBPD_LOG_RESP_SIZE)
+/* Buffer for building the PDLOG string */
+#define BUF_SIZE 80
+
+struct logger_data {
+ struct device *dev;
+ struct cros_ec_dev *ec_dev;
+ u8 ec_buffer[CROS_USBPD_BUFFER_SIZE];
+ struct delayed_work log_work;
+ struct workqueue_struct *log_workqueue;
+};
+
+static const char * const chg_type_names[] = {
+ "None", "PD", "Type-C", "Proprietary", "DCP", "CDP", "SDP",
+ "Other", "VBUS"
+};
+
+static const char * const role_names[] = {
+ "Disconnected", "SRC", "SNK", "SNK (not charging)"
+};
+
+static const char * const fault_names[] = {
+ "---", "OCP", "fast OCP", "OVP", "Discharge"
+};
+
+static int append_str(char *buf, int pos, const char *fmt, ...)
+{
+ va_list args;
+ int i;
+
+ va_start(args, fmt);
+ i = vsnprintf(buf + pos, BUF_SIZE - pos, fmt, args);
+ va_end(args);
+
+ return i;
+}
+
+static struct ec_response_pd_log *ec_get_log_entry(struct logger_data *logger)
+{
+ struct cros_ec_dev *ec_dev = logger->ec_dev;
+ struct cros_ec_command *msg;
+ int ret;
+
+ msg = (struct cros_ec_command *)logger->ec_buffer;
+
+ msg->command = ec_dev->cmd_offset + EC_CMD_PD_GET_LOG_ENTRY;
+ msg->insize = CROS_USBPD_LOG_RESP_SIZE;
+
+ ret = cros_ec_cmd_xfer_status(ec_dev->ec_dev, msg);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ return (struct ec_response_pd_log *)msg->data;
+}
+
+static void cros_usbpd_print_log_entry(struct ec_response_pd_log *r,
+ ktime_t tstamp)
+{
+ const char *fault, *role, *chg_type;
+ struct usb_chg_measures *meas;
+ struct mcdp_info *minfo;
+ int role_idx, type_idx;
+ char buf[BUF_SIZE + 1];
+ struct rtc_time rt;
+ int len = 0;
+ s32 rem;
+ int i;
+
+ /* The timestamp is the number of 1024th of seconds in the past */
+ tstamp = ktime_sub_us(tstamp, r->timestamp << PD_LOG_TIMESTAMP_SHIFT);
+ rt = rtc_ktime_to_tm(tstamp);
+
+ switch (r->type) {
+ case PD_EVENT_MCU_CHARGE:
+ if (r->data & CHARGE_FLAGS_OVERRIDE)
+ len += append_str(buf, len, "override ");
+
+ if (r->data & CHARGE_FLAGS_DELAYED_OVERRIDE)
+ len += append_str(buf, len, "pending_override ");
+
+ role_idx = r->data & CHARGE_FLAGS_ROLE_MASK;
+ role = role_idx < ARRAY_SIZE(role_names) ?
+ role_names[role_idx] : "Unknown";
+
+ type_idx = (r->data & CHARGE_FLAGS_TYPE_MASK)
+ >> CHARGE_FLAGS_TYPE_SHIFT;
+
+ chg_type = type_idx < ARRAY_SIZE(chg_type_names) ?
+ chg_type_names[type_idx] : "???";
+
+ if (role_idx == USB_PD_PORT_POWER_DISCONNECTED ||
+ role_idx == USB_PD_PORT_POWER_SOURCE) {
+ len += append_str(buf, len, "%s", role);
+ break;
+ }
+
+ meas = (struct usb_chg_measures *)r->payload;
+ len += append_str(buf, len, "%s %s %s %dmV max %dmV / %dmA",
+ role, r->data & CHARGE_FLAGS_DUAL_ROLE ?
+ "DRP" : "Charger",
+ chg_type, meas->voltage_now,
+ meas->voltage_max, meas->current_max);
+ break;
+ case PD_EVENT_ACC_RW_FAIL:
+ len += append_str(buf, len, "RW signature check failed");
+ break;
+ case PD_EVENT_PS_FAULT:
+ fault = r->data < ARRAY_SIZE(fault_names) ? fault_names[r->data]
+ : "???";
+ len += append_str(buf, len, "Power supply fault: %s", fault);
+ break;
+ case PD_EVENT_VIDEO_DP_MODE:
+ len += append_str(buf, len, "DP mode %sabled", r->data == 1 ?
+ "en" : "dis");
+ break;
+ case PD_EVENT_VIDEO_CODEC:
+ minfo = (struct mcdp_info *)r->payload;
+ len += append_str(buf, len, "HDMI info: family:%04x chipid:%04x ",
+ MCDP_FAMILY(minfo->family),
+ MCDP_CHIPID(minfo->chipid));
+ len += append_str(buf, len, "irom:%d.%d.%d fw:%d.%d.%d",
+ minfo->irom.major, minfo->irom.minor,
+ minfo->irom.build, minfo->fw.major,
+ minfo->fw.minor, minfo->fw.build);
+ break;
+ default:
+ len += append_str(buf, len, "Event %02x (%04x) [", r->type,
+ r->data);
+
+ for (i = 0; i < PD_LOG_SIZE(r->size_port); i++)
+ len += append_str(buf, len, "%02x ", r->payload[i]);
+
+ len += append_str(buf, len, "]");
+ break;
+ }
+
+ div_s64_rem(ktime_to_ms(tstamp), MSEC_PER_SEC, &rem);
+ pr_info("PDLOG %d/%02d/%02d %02d:%02d:%02d.%03d P%d %s\n",
+ rt.tm_year + 1900, rt.tm_mon + 1, rt.tm_mday,
+ rt.tm_hour, rt.tm_min, rt.tm_sec, rem,
+ PD_LOG_PORT(r->size_port), buf);
+}
+
+static void cros_usbpd_log_check(struct work_struct *work)
+{
+ struct logger_data *logger = container_of(to_delayed_work(work),
+ struct logger_data,
+ log_work);
+ struct device *dev = logger->dev;
+ struct ec_response_pd_log *r;
+ int entries = 0;
+ ktime_t now;
+
+ while (entries++ < CROS_USBPD_MAX_LOG_ENTRIES) {
+ r = ec_get_log_entry(logger);
+ now = ktime_get_real();
+ if (IS_ERR(r)) {
+ dev_dbg(dev, "Cannot get PD log %ld\n", PTR_ERR(r));
+ break;
+ }
+ if (r->type == PD_EVENT_NO_ENTRY)
+ break;
+
+ cros_usbpd_print_log_entry(r, now);
+ }
+
+ queue_delayed_work(logger->log_workqueue, &logger->log_work,
+ CROS_USBPD_LOG_UPDATE_DELAY);
+}
+
+static int cros_usbpd_logger_probe(struct platform_device *pd)
+{
+ struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
+ struct device *dev = &pd->dev;
+ struct logger_data *logger;
+
+ logger = devm_kzalloc(dev, sizeof(*logger), GFP_KERNEL);
+ if (!logger)
+ return -ENOMEM;
+
+ logger->dev = dev;
+ logger->ec_dev = ec_dev;
+
+ platform_set_drvdata(pd, logger);
+
+ /* Retrieve PD event logs periodically */
+ INIT_DELAYED_WORK(&logger->log_work, cros_usbpd_log_check);
+ logger->log_workqueue = create_singlethread_workqueue("cros_usbpd_log");
+ queue_delayed_work(logger->log_workqueue, &logger->log_work,
+ CROS_USBPD_LOG_UPDATE_DELAY);
+
+ return 0;
+}
+
+static int cros_usbpd_logger_remove(struct platform_device *pd)
+{
+ struct logger_data *logger = platform_get_drvdata(pd);
+
+ cancel_delayed_work_sync(&logger->log_work);
+
+ return 0;
+}
+
+static int __maybe_unused cros_usbpd_logger_resume(struct device *dev)
+{
+ struct logger_data *logger = dev_get_drvdata(dev);
+
+ queue_delayed_work(logger->log_workqueue, &logger->log_work,
+ CROS_USBPD_LOG_UPDATE_DELAY);
+
+ return 0;
+}
+
+static int __maybe_unused cros_usbpd_logger_suspend(struct device *dev)
+{
+ struct logger_data *logger = dev_get_drvdata(dev);
+
+ cancel_delayed_work_sync(&logger->log_work);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(cros_usbpd_logger_pm_ops, cros_usbpd_logger_suspend,
+ cros_usbpd_logger_resume);
+
+static struct platform_driver cros_usbpd_logger_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .pm = &cros_usbpd_logger_pm_ops,
+ },
+ .probe = cros_usbpd_logger_probe,
+ .remove = cros_usbpd_logger_remove,
+};
+
+module_platform_driver(cros_usbpd_logger_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Logging driver for ChromeOS EC USBPD Charger.");
+MODULE_ALIAS("platform:" DRV_NAME);