usb: chipidea: move role to debugfs

Manual role switching function is there for debugging purposes, so has
to move to debugfs.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/core.c

@@ -280,38 +280,6 @@ static void ci_role_work(struct work_struct *work)
 	}
 }
 
-static ssize_t show_role(struct device *dev, struct device_attribute *attr,
-			 char *buf)
-{
-	struct ci13xxx *ci = dev_get_drvdata(dev);
-
-	return sprintf(buf, "%s\n", ci_role(ci)->name);
-}
-
-static ssize_t store_role(struct device *dev, struct device_attribute *attr,
-			  const char *buf, size_t count)
-{
-	struct ci13xxx *ci = dev_get_drvdata(dev);
-	enum ci_role role;
-	int ret;
-
-	for (role = CI_ROLE_HOST; role < CI_ROLE_END; role++)
-		if (ci->roles[role] && !strcmp(buf, ci->roles[role]->name))
-			break;
-
-	if (role == CI_ROLE_END || role == ci->role)
-		return -EINVAL;
-
-	ci_role_stop(ci);
-	ret = ci_role_start(ci, role);
-	if (ret)
-		return ret;
-
-	return count;
-}
-
-static DEVICE_ATTR(role, S_IRUSR | S_IWUSR, show_role, store_role);
-
 static irqreturn_t ci_irq(int irq, void *data)
 {
 	struct ci13xxx *ci = data;
@@ -484,17 +452,11 @@ static int ci_hdrc_probe(struct platform_device *pdev)
 	if (ret)
 		goto stop;
 
-	ret = device_create_file(dev, &dev_attr_role);
-	if (ret)
-		goto rm_attr;
-
 	if (ci->is_otg)
 		hw_write(ci, OP_OTGSC, OTGSC_IDIE, OTGSC_IDIE);
 
 	return ret;
 
-rm_attr:
-	device_remove_file(dev, &dev_attr_role);
 stop:
 	ci_role_stop(ci);
 rm_wq:
@@ -510,7 +472,6 @@ static int ci_hdrc_remove(struct platform_device *pdev)
 
 	flush_workqueue(ci->wq);
 	destroy_workqueue(ci->wq);
-	device_remove_file(ci->dev, &dev_attr_role);
 	free_irq(ci->irq, ci);
 	ci_role_stop(ci);
 

drivers/usb/chipidea/debug.c

@@ -199,6 +199,55 @@ static const struct file_operations ci_requests_fops = {
 	.release	= single_release,
 };
 
+static int ci_role_show(struct seq_file *s, void *data)
+{
+	struct ci13xxx *ci = s->private;
+
+	seq_printf(s, "%s\n", ci_role(ci)->name);
+
+	return 0;
+}
+
+static ssize_t ci_role_write(struct file *file, const char __user *ubuf,
+			     size_t count, loff_t *ppos)
+{
+	struct seq_file *s = file->private_data;
+	struct ci13xxx *ci = s->private;
+	enum ci_role role;
+	char buf[8];
+	int ret;
+
+	if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+		return -EFAULT;
+
+	for (role = CI_ROLE_HOST; role < CI_ROLE_END; role++)
+		if (ci->roles[role] &&
+		    !strncmp(buf, ci->roles[role]->name,
+			     strlen(ci->roles[role]->name)))
+			break;
+
+	if (role == CI_ROLE_END || role == ci->role)
+		return -EINVAL;
+
+	ci_role_stop(ci);
+	ret = ci_role_start(ci, role);
+
+	return ret ? ret : count;
+}
+
+static int ci_role_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, ci_role_show, inode->i_private);
+}
+
+static const struct file_operations ci_role_fops = {
+	.open		= ci_role_open,
+	.write		= ci_role_write,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
 /**
  * dbg_create_files: initializes the attribute interface
  * @ci: device
@@ -230,6 +279,11 @@ int dbg_create_files(struct ci13xxx *ci)
 
 	dent = debugfs_create_file("requests", S_IRUGO, ci->debugfs, ci,
 				   &ci_requests_fops);
+	if (!dent)
+		goto err;
+
+	dent = debugfs_create_file("role", S_IRUGO | S_IWUSR, ci->debugfs, ci,
+				   &ci_role_fops);
 	if (dent)
 		return 0;
 err: