1 files changed, 52 insertions, 8 deletions

diff --git a/drivers/usb/otg/ulpi.c b/drivers/usb/otg/ulpi.c
index ccc81950822b..059d9ac0ab5b 100644
--- a/drivers/usb/otg/ulpi.c
+++ b/drivers/usb/otg/ulpi.c
@@ -29,12 +29,23 @@
 #include <linux/usb/otg.h>
 #include <linux/usb/ulpi.h>
 
+
+struct ulpi_info {
+        unsigned int    id;
+        char            *name;
+};
+
 #define ULPI_ID(vendor, product) (((vendor) << 16) | (product))
+#define ULPI_INFO(_id, _name)           \
+        {                               \
+                .id     = (_id),        \
+                .name   = (_name),      \
+        }
 
 /* ULPI hardcoded IDs, used for probing */
-static unsigned int ulpi_ids[] = {
-        ULPI_ID(0x04cc, 0x1504),        /* NXP ISP1504 */
-        ULPI_ID(0x0424, 0x0006),        /* SMSC USB3319 */
+static struct ulpi_info ulpi_ids[] = {
+        ULPI_INFO(ULPI_ID(0x04cc, 0x1504), "NXP ISP1504"),
+        ULPI_INFO(ULPI_ID(0x0424, 0x0006), "SMSC USB3319"),
 };
 
 static int ulpi_set_otg_flags(struct otg_transceiver *otg)
@@ -137,6 +148,32 @@ static int ulpi_set_flags(struct otg_transceiver *otg)
         return ulpi_set_fc_flags(otg);
 }
 
+static int ulpi_check_integrity(struct otg_transceiver *otg)
+{
+        int ret, i;
+        unsigned int val = 0x55;
+
+        for (i = 0; i < 2; i++) {
+                ret = otg_io_write(otg, val, ULPI_SCRATCH);
+                if (ret < 0)
+                        return ret;
+
+                ret = otg_io_read(otg, ULPI_SCRATCH);
+                if (ret < 0)
+                        return ret;
+
+                if (ret != val) {
+                        pr_err("ULPI integrity check: failed!");
+                        return -ENODEV;
+                }
+                val = val << 1;
+        }
+
+        pr_info("ULPI integrity check: passed.\n");
+
+        return 0;
+}
+
 static int ulpi_init(struct otg_transceiver *otg)
 {
         int i, vid, pid, ret;
@@ -153,12 +190,19 @@ static int ulpi_init(struct otg_transceiver *otg)
 
         pr_info("ULPI transceiver vendor/product ID 0x%04x/0x%04x\n", vid, pid);
 
-        for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++)
-                if (ulpi_ids[i] == ULPI_ID(vid, pid))
-                        return ulpi_set_flags(otg);
+        for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++) {
+                if (ulpi_ids[i].id == ULPI_ID(vid, pid)) {
+                        pr_info("Found %s ULPI transceiver.\n",
+                                ulpi_ids[i].name);
+                        break;
+                }
+        }
+
+        ret = ulpi_check_integrity(otg);
+        if (ret)
+                return ret;
 
-        pr_err("ULPI ID does not match any known transceiver.\n");
-        return -ENODEV;
+        return ulpi_set_flags(otg);
 }
 
 static int ulpi_set_host(struct otg_transceiver *otg, struct usb_bus *host)