USB: otg/ulpi: bail out on read errors
otg_read may return errnos, so bail out correctly to prevent bogus
ID-numbers.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Daniel Mack <daniel@caiaq.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/otg/ulpi.c b/drivers/usb/otg/ulpi.c
index b1b3469..d331b22 100644
--- a/drivers/usb/otg/ulpi.c
+++ b/drivers/usb/otg/ulpi.c
@@ -59,12 +59,17 @@
static int ulpi_init(struct otg_transceiver *otg)
{
- int i, vid, pid;
+ int i, vid, pid, ret;
+ u32 ulpi_id = 0;
- vid = (otg_io_read(otg, ULPI_VENDOR_ID_HIGH) << 8) |
- otg_io_read(otg, ULPI_VENDOR_ID_LOW);
- pid = (otg_io_read(otg, ULPI_PRODUCT_ID_HIGH) << 8) |
- otg_io_read(otg, ULPI_PRODUCT_ID_LOW);
+ for (i = 0; i < 4; i++) {
+ ret = otg_io_read(otg, ULPI_PRODUCT_ID_HIGH - i);
+ if (ret < 0)
+ return ret;
+ ulpi_id = (ulpi_id << 8) | ret;
+ }
+ vid = ulpi_id & 0xffff;
+ pid = ulpi_id >> 16;
pr_info("ULPI transceiver vendor/product ID 0x%04x/0x%04x\n", vid, pid);