platform/chrome: cros_ec: Separate logic for getting panic info

Create a separate function called cros_ec_get_panicinfo for getting
panic info from EC.

Currently cros_ec_create_panicinfo is the only caller.

Signed-off-by: Rob Barnes <robbarnes@google.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20230410165817.932449-1-robbarnes@google.com

diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
index a98c529..414ebff 100644 (file)
--- a/drivers/platform/chrome/cros_ec_debugfs.c
+++ b/drivers/platform/chrome/cros_ec_debugfs.c
@@ -400,24 +400,48 @@ 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;
@@ -427,7 +451,7 @@ 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,
@@ -436,7 +460,7 @@ static int cros_ec_create_panicinfo(struct cros_ec_debugfs *debug_info)
        return 0;
 
 free:
-       devm_kfree(debug_info->ec->dev, msg);
+       devm_kfree(debug_info->ec->dev, data);
        return ret;
 }