This patch adds debugfs to set the "b-device" mode for using a board
which is not connected to the ID pin (e.g. CN11 on Salvator-X).
If we want to use peripheral mode on such a board, we have to disable
VBUS output first. So, this patch can set such a mode as the following:
# mount -t debugfs none /sys/kernel/debug
# modprobe renesas_usb3
# modprobe g_mass_storage file=/dev/shm/test.bin
# echo 1 > /sys/kernel/debug/ee020000.usb/b_device
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
drivers/usb/gadget/udc/renesas_usb3.c | 78 ++++++++++++++++++++++++++++++++++-
1 file changed, 76 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index d827832..3415d32 100644
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -8,6 +8,7 @@
* the Free Software Foundation; version 2 of the License.
*/
+#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
@@ -20,6 +21,7 @@
#include <linux/pm_runtime.h>
#include <linux/sizes.h>
#include <linux/slab.h>
+#include <linux/uaccess.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
@@ -344,6 +346,7 @@ struct renesas_usb3 {
bool workaround_for_vbus;
bool extcon_host; /* check id and set EXTCON_USB_HOST */
bool extcon_usb; /* check vbus and set EXTCON_USB */
+ bool forced_b_device;
};
#define gadget_to_renesas_usb3(_gadget) \
@@ -660,7 +663,9 @@ static void usb3_mode_config(struct renesas_usb3 *usb3, bool host, bool a_dev)
spin_lock_irqsave(&usb3->lock, flags);
usb3_set_mode(usb3, host);
usb3_vbus_out(usb3, a_dev);
- if (!host && a_dev) /* for A-Peripheral */
+ /* for A-Peripheral or forced B-device mode */
+ if ((!host && a_dev) ||
+ (usb3->workaround_for_vbus && usb3->forced_b_device))
usb3_connect(usb3);
spin_unlock_irqrestore(&usb3->lock, flags);
}
@@ -674,7 +679,7 @@ static void usb3_check_id(struct renesas_usb3 *usb3)
{
usb3->extcon_host = usb3_is_a_device(usb3);
- if (usb3->extcon_host)
+ if (usb3->extcon_host && !usb3->forced_b_device)
usb3_mode_config(usb3, true, true);
else
usb3_mode_config(usb3, false, false);
@@ -2266,6 +2271,9 @@ static ssize_t role_store(struct device *dev, struct device_attribute *attr,
if (!usb3->driver)
return -ENODEV;
+ if (usb3->forced_b_device)
+ return -EBUSY;
+
if (!strncmp(buf, "host", strlen("host")))
new_mode_is_host = true;
else if (!strncmp(buf, "peripheral", strlen("peripheral")))
@@ -2293,6 +2301,70 @@ static ssize_t role_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RW(role);
+static int renesas_usb3_b_device_show(struct seq_file *s, void *unused)
+{
+ struct renesas_usb3 *usb3 = s->private;
+
+ seq_printf(s, "%d\n", usb3->forced_b_device);
+
+ return 0;
+}
+
+static int renesas_usb3_b_device_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, renesas_usb3_b_device_show, inode->i_private);
+}
+
+static ssize_t renesas_usb3_b_device_write(struct file *file,
+ const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ struct seq_file *s = file->private_data;
+ struct renesas_usb3 *usb3 = s->private;
+ char buf[32];
+
+ if (!usb3->driver)
+ return -ENODEV;
+
+ if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+ return -EFAULT;
+
+ if (!strncmp(buf, "1", 1))
+ usb3->forced_b_device = true;
+ else
+ usb3->forced_b_device = false;
+
+ /* Let this driver call usb3_connect() anyway */
+ usb3_check_id(usb3);
+
+ return count;
+}
+
+static const struct file_operations renesas_usb3_b_device_fops = {
+ .open = renesas_usb3_b_device_open,
+ .write = renesas_usb3_b_device_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void renesas_usb3_debugfs_init(struct renesas_usb3 *usb3,
+ struct device *dev)
+{
+ struct dentry *root, *file;
+
+ root = debugfs_create_dir(dev_name(dev), NULL);
+ if (IS_ERR_OR_NULL(root)) {
+ dev_info(dev, "%s: Can't create the root\n", __func__);
+ return;
+ }
+
+ file = debugfs_create_file("b_device", 0644, root, usb3,
+ &renesas_usb3_b_device_fops);
+ if (!file)
+ dev_info(dev, "%s: Can't create debugfs mode\n", __func__);
+}
+
/*------- platform_driver ------------------------------------------------*/
static int renesas_usb3_remove(struct platform_device *pdev)
{
@@ -2510,6 +2582,8 @@ static int renesas_usb3_probe(struct platform_device *pdev)
usb3->workaround_for_vbus = priv->workaround_for_vbus;
+ renesas_usb3_debugfs_init(usb3, &pdev->dev);
+
dev_info(&pdev->dev, "probed\n");
return 0;
--
1.9.1
--
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