diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/otg/ulpi.c | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/drivers/usb/otg/ulpi.c b/drivers/usb/otg/ulpi.c index ccc81950822b..e0d2a5c504cc 100644 --- a/drivers/usb/otg/ulpi.c +++ b/drivers/usb/otg/ulpi.c @@ -137,6 +137,32 @@ 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; @@ -155,10 +181,13 @@ static int ulpi_init(struct otg_transceiver *otg) for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++) if (ulpi_ids[i] == ULPI_ID(vid, pid)) - return ulpi_set_flags(otg); + 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) |