1 files changed, 95 insertions, 49 deletions

diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
index 21d973fc6be2..d10f9561990c 100644
--- a/drivers/platform/chrome/cros_ec_debugfs.c
+++ b/drivers/platform/chrome/cros_ec_debugfs.c
@@ -7,6 +7,7 @@
 #include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/fs.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/platform_data/cros_ec_commands.h>
@@ -25,6 +26,10 @@
 
 #define CIRC_ADD(idx, size, value)	(((idx) + (value)) & ((size) - 1))
 
+static unsigned int log_poll_period_ms = LOG_POLL_SEC * MSEC_PER_SEC;
+module_param(log_poll_period_ms, uint, 0644);
+MODULE_PARM_DESC(log_poll_period_ms, "EC log polling period(ms)");
+
 /* waitqueue for log readers */
 static DECLARE_WAIT_QUEUE_HEAD(cros_ec_debugfs_log_wq);
 
@@ -38,6 +43,8 @@ static DECLARE_WAIT_QUEUE_HEAD(cros_ec_debugfs_log_wq);
  * @log_mutex: mutex to protect circular buffer
  * @log_poll_work: recurring task to poll EC for new console log data
  * @panicinfo_blob: panicinfo debugfs blob
+ * @notifier_panic: notifier_block to let kernel to flush buffered log
+ *                  when EC panic
  */
 struct cros_ec_debugfs {
 	struct cros_ec_dev *ec;
@@ -49,11 +56,12 @@ struct cros_ec_debugfs {
 	struct delayed_work log_poll_work;
 	/* EC panicinfo */
 	struct debugfs_blob_wrapper panicinfo_blob;
+	struct notifier_block notifier_panic;
 };
 
 /*
  * We need to make sure that the EC log buffer on the UART is large enough,
- * so that it is unlikely enough to overlow within LOG_POLL_SEC.
+ * so that it is unlikely enough to overlow within log_poll_period_ms.
  */
 static void cros_ec_console_log_work(struct work_struct *__work)
 {
@@ -115,7 +123,7 @@ static void cros_ec_console_log_work(struct work_struct *__work)
 
 resched:
 	schedule_delayed_work(&debug_info->log_poll_work,
-			      msecs_to_jiffies(LOG_POLL_SEC * 1000));
+			      msecs_to_jiffies(log_poll_period_ms));
 }
 
 static int cros_ec_console_log_open(struct inode *inode, struct file *file)
@@ -199,22 +207,15 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
 	char read_buf[EC_USB_PD_MAX_PORTS * 40], *p = read_buf;
 	struct cros_ec_debugfs *debug_info = file->private_data;
 	struct cros_ec_device *ec_dev = debug_info->ec->ec_dev;
-	struct {
-		struct cros_ec_command msg;
-		union {
-			struct ec_response_usb_pd_control_v1 resp;
-			struct ec_params_usb_pd_control params;
-		};
-	} __packed ec_buf;
-	struct cros_ec_command *msg;
-	struct ec_response_usb_pd_control_v1 *resp;
-	struct ec_params_usb_pd_control *params;
+	DEFINE_RAW_FLEX(struct cros_ec_command, msg, data,
+			MAX(sizeof(struct ec_response_usb_pd_control_v1),
+			    sizeof(struct ec_params_usb_pd_control)));
+	struct ec_response_usb_pd_control_v1 *resp =
+			(struct ec_response_usb_pd_control_v1 *)msg->data;
+	struct ec_params_usb_pd_control *params =
+			(struct ec_params_usb_pd_control *)msg->data;
 	int i;
 
-	msg = &ec_buf.msg;
-	params = (struct ec_params_usb_pd_control *)msg->data;
-	resp = (struct ec_response_usb_pd_control_v1 *)msg->data;
-
 	msg->command = EC_CMD_USB_PD_CONTROL;
 	msg->version = 1;
 	msg->insize = sizeof(*resp);
@@ -245,17 +246,15 @@ static ssize_t cros_ec_pdinfo_read(struct file *file,
 
 static bool cros_ec_uptime_is_supported(struct cros_ec_device *ec_dev)
 {
-	struct {
-		struct cros_ec_command cmd;
-		struct ec_response_uptime_info resp;
-	} __packed msg = {};
+	DEFINE_RAW_FLEX(struct cros_ec_command, msg, data,
+			sizeof(struct ec_response_uptime_info));
 	int ret;
 
-	msg.cmd.command = EC_CMD_GET_UPTIME_INFO;
-	msg.cmd.insize = sizeof(msg.resp);
+	msg->command = EC_CMD_GET_UPTIME_INFO;
+	msg->insize = sizeof(struct ec_response_uptime_info);
 
-	ret = cros_ec_cmd_xfer_status(ec_dev, &msg.cmd);
-	if (ret == -EPROTO && msg.cmd.result == EC_RES_INVALID_COMMAND)
+	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
+	if (ret == -EPROTO && msg->result == EC_RES_INVALID_COMMAND)
 		return false;
 
 	/* Other errors maybe a transient error, do not rule about support. */
@@ -267,20 +266,17 @@ static ssize_t cros_ec_uptime_read(struct file *file, char __user *user_buf,
 {
 	struct cros_ec_debugfs *debug_info = file->private_data;
 	struct cros_ec_device *ec_dev = debug_info->ec->ec_dev;
-	struct {
-		struct cros_ec_command cmd;
-		struct ec_response_uptime_info resp;
-	} __packed msg = {};
-	struct ec_response_uptime_info *resp;
+	DEFINE_RAW_FLEX(struct cros_ec_command, msg, data,
+			sizeof(struct ec_response_uptime_info));
+	struct ec_response_uptime_info *resp =
+				(struct ec_response_uptime_info *)msg->data;
 	char read_buf[32];
 	int ret;
 
-	resp = (struct ec_response_uptime_info *)&msg.resp;
-
-	msg.cmd.command = EC_CMD_GET_UPTIME_INFO;
-	msg.cmd.insize = sizeof(*resp);
+	msg->command = EC_CMD_GET_UPTIME_INFO;
+	msg->insize = sizeof(*resp);
 
-	ret = cros_ec_cmd_xfer_status(ec_dev, &msg.cmd);
+	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
 	if (ret < 0)
 		return ret;
 
@@ -294,7 +290,6 @@ static const struct file_operations cros_ec_console_log_fops = {
 	.owner = THIS_MODULE,
 	.open = cros_ec_console_log_open,
 	.read = cros_ec_console_log_read,
-	.llseek = no_llseek,
 	.poll = cros_ec_console_log_poll,
 	.release = cros_ec_console_log_release,
 };
@@ -326,6 +321,7 @@ static int ec_read_version_supported(struct cros_ec_dev *ec)
 	if (!msg)
 		return 0;
 
+	msg->version = 1;
 	msg->command = EC_CMD_GET_CMD_VERSIONS + ec->cmd_offset;
 	msg->outsize = sizeof(*params);
 	msg->insize = sizeof(*response);
@@ -397,24 +393,48 @@ static void cros_ec_cleanup_console_log(struct cros_ec_debugfs *debug_info)
 	}
 }
 
-static int cros_ec_create_panicinfo(struct cros_ec_debugfs *debug_info)
+/*
+ * Returns the size of the panicinfo data fetched from the EC
+ */
+static int cros_ec_get_panicinfo(struct cros_ec_device *ec_dev, uint8_t *data,
+				 int data_size)
 {
-	struct cros_ec_device *ec_dev = debug_info->ec->ec_dev;
 	int ret;
 	struct cros_ec_command *msg;
-	int insize;
 
-	insize = ec_dev->max_response;
+	if (!data || data_size <= 0 || data_size > ec_dev->max_response)
+		return -EINVAL;
 
-	msg = devm_kzalloc(debug_info->ec->dev,
-			sizeof(*msg) + insize, GFP_KERNEL);
+	msg = kzalloc(sizeof(*msg) + data_size, GFP_KERNEL);
 	if (!msg)
 		return -ENOMEM;
 
 	msg->command = EC_CMD_GET_PANIC_INFO;
-	msg->insize = insize;
+	msg->insize = data_size;
 
 	ret = cros_ec_cmd_xfer_status(ec_dev, msg);
+	if (ret < 0)
+		goto free;
+
+	memcpy(data, msg->data, data_size);
+
+free:
+	kfree(msg);
+	return ret;
+}
+
+static int cros_ec_create_panicinfo(struct cros_ec_debugfs *debug_info)
+{
+	struct cros_ec_device *ec_dev = debug_info->ec->ec_dev;
+	int ret;
+	void *data;
+
+	data = devm_kzalloc(debug_info->ec->dev, ec_dev->max_response,
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	ret = cros_ec_get_panicinfo(ec_dev, data, ec_dev->max_response);
 	if (ret < 0) {
 		ret = 0;
 		goto free;
@@ -424,19 +444,35 @@ static int cros_ec_create_panicinfo(struct cros_ec_debugfs *debug_info)
 	if (ret == 0)
 		goto free;
 
-	debug_info->panicinfo_blob.data = msg->data;
+	debug_info->panicinfo_blob.data = data;
 	debug_info->panicinfo_blob.size = ret;
 
-	debugfs_create_blob("panicinfo", S_IFREG | 0444, debug_info->dir,
+	debugfs_create_blob("panicinfo", 0444, debug_info->dir,
 			    &debug_info->panicinfo_blob);
 
 	return 0;
 
 free:
-	devm_kfree(debug_info->ec->dev, msg);
+	devm_kfree(debug_info->ec->dev, data);
 	return ret;
 }
 
+static int cros_ec_debugfs_panic_event(struct notifier_block *nb,
+				       unsigned long queued_during_suspend, void *_notify)
+{
+	struct cros_ec_debugfs *debug_info =
+		container_of(nb, struct cros_ec_debugfs, notifier_panic);
+
+	if (debug_info->log_buffer.buf) {
+		/* Force log poll work to run immediately */
+		mod_delayed_work(debug_info->log_poll_work.wq, &debug_info->log_poll_work, 0);
+		/* Block until log poll work finishes */
+		flush_delayed_work(&debug_info->log_poll_work);
+	}
+
+	return NOTIFY_DONE;
+}
+
 static int cros_ec_debugfs_probe(struct platform_device *pd)
 {
 	struct cros_ec_dev *ec = dev_get_drvdata(pd->dev.parent);
@@ -473,6 +509,12 @@ static int cros_ec_debugfs_probe(struct platform_device *pd)
 	debugfs_create_u16("suspend_timeout_ms", 0664, debug_info->dir,
 			   &ec->ec_dev->suspend_timeout_ms);
 
+	debug_info->notifier_panic.notifier_call = cros_ec_debugfs_panic_event;
+	ret = blocking_notifier_chain_register(&ec->ec_dev->panic_notifier,
+					       &debug_info->notifier_panic);
+	if (ret)
+		goto remove_debugfs;
+
 	ec->debug_info = debug_info;
 
 	dev_set_drvdata(&pd->dev, ec);
@@ -484,14 +526,12 @@ remove_debugfs:
 	return ret;
 }
 
-static int cros_ec_debugfs_remove(struct platform_device *pd)
+static void cros_ec_debugfs_remove(struct platform_device *pd)
 {
 	struct cros_ec_dev *ec = dev_get_drvdata(pd->dev.parent);
 
 	debugfs_remove_recursive(ec->debug_info->dir);
 	cros_ec_cleanup_console_log(ec->debug_info);
-
-	return 0;
 }
 
 static int __maybe_unused cros_ec_debugfs_suspend(struct device *dev)
@@ -517,6 +557,12 @@ static int __maybe_unused cros_ec_debugfs_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(cros_ec_debugfs_pm_ops,
 			 cros_ec_debugfs_suspend, cros_ec_debugfs_resume);
 
+static const struct platform_device_id cros_ec_debugfs_id[] = {
+	{ DRV_NAME, 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(platform, cros_ec_debugfs_id);
+
 static struct platform_driver cros_ec_debugfs_driver = {
 	.driver = {
 		.name = DRV_NAME,
@@ -525,10 +571,10 @@ static struct platform_driver cros_ec_debugfs_driver = {
 	},
 	.probe = cros_ec_debugfs_probe,
 	.remove = cros_ec_debugfs_remove,
+	.id_table = cros_ec_debugfs_id,
 };
 
 module_platform_driver(cros_ec_debugfs_driver);
 
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Debug logs for ChromeOS EC");
-MODULE_ALIAS("platform:" DRV_NAME);