[PATCH 2/2] drivers: hid: warn feature report 0x81

[Henry Castro]

Unfortunately, my PS DualShock 4, does not support
the feature 0x81 to get the MAC address. Instead,
use a unique hash to fake a MAC address, so I can
use DS4 to play Retroarch :)

Signed-off-by: Henry Castro <hcvcastro@xxxxxxxxx>
---

> Just for reference if you want to try out if 0x12 works, you can try
> this code. This is from the new driver (ps_get_report is from
> hid-playstation, but you can just use one of the existing hid calls)
> if you wanted to try.

It works with my 2 DS4 =)


		if (sc->hdev->bus == BUS_USB) {
			buf = kzalloc(DS4_FEATURE_REPORT_PAIRING_INFO_SIZE, GFP_KERNEL);
			if (!buf)
				return -ENOMEM;

			ret = hid_hw_raw_request(sc->hdev, DS4_FEATURE_REPORT_PAIRING_INFO, buf,
						 DS4_FEATURE_REPORT_PAIRING_INFO_SIZE, HID_FEATURE_REPORT,
						 HID_REQ_GET_REPORT);
			if (ret != DS4_FEATURE_REPORT_PAIRING_INFO_SIZE) {
				hid_err(sc->hdev, "Failed to retrieve DualShock4 pairing info:%pe\n", ERR_PTR(ret));
				goto out_free;
			}

			memcpy(sc->mac_address, &buf[1], sizeof(sc->mac_address));




 drivers/hid/hid-sony.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/hid/hid-sony.c b/drivers/hid/hid-sony.c
index 656caa07b25f..e3e9c58887cf 100644
--- a/drivers/hid/hid-sony.c
+++ b/drivers/hid/hid-sony.c
@@ -2641,13 +2641,14 @@ static int sony_check_add(struct sony_sc *sc)
 				HID_REQ_GET_REPORT);

 		if (ret != DS4_FEATURE_REPORT_0x81_SIZE) {
-			hid_err(sc->hdev, "failed to retrieve feature report 0x81 with the DualShock 4 MAC address\n");
-			ret = ret < 0 ? ret : -EINVAL;
-			goto out_free;
+			uint32_t hash = full_name_hash(NULL, dev_name(&sc->hdev->dev),
+						       strlen(dev_name(&sc->hdev->dev)));
+			hid_warn(sc->hdev, "failed to retrieve feature report 0x81 with the DualShock 4 MAC address\n");
+			memcpy(sc->mac_address, &hash, sizeof(hash));
+		} else {
+			memcpy(sc->mac_address, &buf[1], sizeof(sc->mac_address));
 		}

-		memcpy(sc->mac_address, &buf[1], sizeof(sc->mac_address));
-
 		snprintf(sc->hdev->uniq, sizeof(sc->hdev->uniq),
 			 "%pMR", sc->mac_address);
 	} else if ((sc->quirks & SIXAXIS_CONTROLLER_USB) ||
--
2.20.1