[PATCH v2 1/2] usb: mtu3: add a vbus debugfs interface

From: Chunfeng Yun
Date: Thu Aug 03 2017 - 22:33:00 EST


Provides a new vbus debugfs interface used to turn on/off vbus
regulator, it also can be used to get/put reference count of
vbus, due to sometimes we need keep it alive when manually switch
mtu3 to device mode.

Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
---
drivers/usb/mtu3/mtu3_dr.c | 58 ++++++++++++++++++++++++++++++++++++++------
1 file changed, 50 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3_dr.c b/drivers/usb/mtu3/mtu3_dr.c
index 11a0d3b..5602561 100644
--- a/drivers/usb/mtu3/mtu3_dr.c
+++ b/drivers/usb/mtu3/mtu3_dr.c
@@ -322,23 +322,65 @@ static ssize_t ssusb_mode_write(struct file *file,
.release = single_release,
};

+static int ssusb_vbus_show(struct seq_file *sf, void *unused)
+{
+ struct ssusb_mtk *ssusb = sf->private;
+ struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
+
+ seq_printf(sf, "vbus state: %s\n(echo on/off)\n",
+ regulator_is_enabled(otg_sx->vbus) ? "on" : "off");
+
+ return 0;
+}
+
+static int ssusb_vbus_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, ssusb_vbus_show, inode->i_private);
+}
+
+static ssize_t ssusb_vbus_write(struct file *file,
+ const char __user *ubuf, size_t count, loff_t *ppos)
+{
+ struct seq_file *sf = file->private_data;
+ struct ssusb_mtk *ssusb = sf->private;
+ struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
+ char buf[16];
+ bool enable;
+
+ if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+ return -EFAULT;
+
+ if (kstrtobool(buf, &enable)) {
+ dev_err(ssusb->dev, "wrong setting\n");
+ return -EINVAL;
+ }
+
+ ssusb_set_vbus(otg_sx, enable);
+
+ return count;
+}
+
+static const struct file_operations ssusb_vbus_fops = {
+ .open = ssusb_vbus_open,
+ .write = ssusb_vbus_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static void ssusb_debugfs_init(struct ssusb_mtk *ssusb)
{
struct dentry *root;
- struct dentry *file;

root = debugfs_create_dir(dev_name(ssusb->dev), usb_debug_root);
- if (IS_ERR_OR_NULL(root)) {
- if (!root)
- dev_err(ssusb->dev, "create debugfs root failed\n");
+ if (!root) {
+ dev_err(ssusb->dev, "create debugfs root failed\n");
return;
}
ssusb->dbgfs_root = root;

- file = debugfs_create_file("mode", S_IRUGO | S_IWUSR, root,
- ssusb, &ssusb_mode_fops);
- if (!file)
- dev_dbg(ssusb->dev, "create debugfs mode failed\n");
+ debugfs_create_file("mode", 0644, root, ssusb, &ssusb_mode_fops);
+ debugfs_create_file("vbus", 0644, root, ssusb, &ssusb_vbus_fops);
}

static void ssusb_debugfs_exit(struct ssusb_mtk *ssusb)
--
1.7.9.5