summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorIgor Grinberg <grinberg@compulab.co.il>2010-10-10 17:59:18 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2010-10-22 19:22:10 +0200
commita9138192d0e716c3e9714b3fe03543d93ebbad9f (patch)
tree9846352e032cf59df136953f1fb36d27839af9b1 /drivers
parentUSB: opticon: Whitespace fixes in opticon driver (diff)
downloadlinux-a9138192d0e716c3e9714b3fe03543d93ebbad9f.tar.xz
linux-a9138192d0e716c3e9714b3fe03543d93ebbad9f.zip
USB: otg/ulpi: improve ulpi phy detection.
Improve ulpi phy detection by utilizing the "scratch" register. Allow unknown ulpi phy work without the need to hard-code the id. Signed-off-by: Igor Grinberg <grinberg@compulab.co.il> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/usb/otg/ulpi.c35
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)