usb: dwc3: gadget: allow testmodes changes via debugfs

This is very useful for low level Link Testing where
we might not have a USB Host stack, only a scope to
verify signal integrity.

Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 92 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c
index 433c97c15fc5..c7e85024fda8 100644
--- a/drivers/usb/dwc3/debugfs.c
+++ b/drivers/usb/dwc3/debugfs.c
@@ -46,6 +46,8 @@
 #include <linux/delay.h>
 #include <linux/uaccess.h>
 
+#include <linux/usb/ch9.h>
+
 #include "core.h"
 #include "gadget.h"
 #include "io.h"
@@ -464,6 +466,89 @@ static const struct file_operations dwc3_mode_fops = {
         .release                = single_release,
 };
 
+static int dwc3_testmode_show(struct seq_file *s, void *unused)
+{
+        struct dwc3             *dwc = s->private;
+        unsigned long           flags;
+        u32                     reg;
+
+        spin_lock_irqsave(&dwc->lock, flags);
+        reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+        reg &= DWC3_DCTL_TSTCTRL_MASK;
+        reg >>= 1;
+        spin_unlock_irqrestore(&dwc->lock, flags);
+
+        switch (reg) {
+        case 0:
+                seq_printf(s, "no test\n");
+                break;
+        case TEST_J:
+                seq_printf(s, "test_j\n");
+                break;
+        case TEST_K:
+                seq_printf(s, "test_k\n");
+                break;
+        case TEST_SE0_NAK:
+                seq_printf(s, "test_se0_nak\n");
+                break;
+        case TEST_PACKET:
+                seq_printf(s, "test_packet\n");
+                break;
+        case TEST_FORCE_EN:
+                seq_printf(s, "test_force_enable\n");
+                break;
+        default:
+                seq_printf(s, "UNKNOWN %d\n", reg);
+        }
+
+        return 0;
+}
+
+static int dwc3_testmode_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, dwc3_testmode_show, inode->i_private);
+}
+
+static ssize_t dwc3_testmode_write(struct file *file,
+                const char __user *ubuf, size_t count, loff_t *ppos)
+{
+        struct seq_file         *s = file->private_data;
+        struct dwc3             *dwc = s->private;
+        unsigned long           flags;
+        u32                     testmode = 0;
+        char                    buf[32];
+
+        if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+                return -EFAULT;
+
+        if (!strncmp(buf, "test_j", 6))
+                testmode = TEST_J;
+        else if (!strncmp(buf, "test_k", 6))
+                testmode = TEST_K;
+        else if (!strncmp(buf, "test_se0_nak", 13))
+                testmode = TEST_SE0_NAK;
+        else if (!strncmp(buf, "test_packet", 12))
+                testmode = TEST_PACKET;
+        else if (!strncmp(buf, "test_force_enable", 18))
+                testmode = TEST_FORCE_EN;
+        else
+                testmode = 0;
+
+        spin_lock_irqsave(&dwc->lock, flags);
+        dwc3_gadget_set_test_mode(dwc, testmode);
+        spin_unlock_irqrestore(&dwc->lock, flags);
+
+        return count;
+}
+
+static const struct file_operations dwc3_testmode_fops = {
+        .open                   = dwc3_testmode_open,
+        .write                  = dwc3_testmode_write,
+        .read                   = seq_read,
+        .llseek                 = seq_lseek,
+        .release                = single_release,
+};
+
 int __devinit dwc3_debugfs_init(struct dwc3 *dwc)
 {
         struct dentry           *root;
@@ -492,6 +577,13 @@ int __devinit dwc3_debugfs_init(struct dwc3 *dwc)
                 goto err1;
         }
 
+        file = debugfs_create_file("testmode", S_IRUGO | S_IWUSR, root,
+                        dwc, &dwc3_testmode_fops);
+        if (IS_ERR(file)) {
+                ret = PTR_ERR(file);
+                goto err1;
+        }
+
         return 0;
 
 err1: