Merge tag 'mvebu-fixes-3.17' of git://git.infradead.org/linux-mvebu into next/fixes...

[cascardo/linux.git] / drivers / hid / hid-huion.c

diff --git a/drivers/hid/hid-huion.c b/drivers/hid/hid-huion.c
index 60f44cd..61b68ca 100644 (file)
--- a/drivers/hid/hid-huion.c
+++ b/drivers/hid/hid-huion.c
@@ -84,6 +84,15 @@ static const __u8 huion_tablet_rdesc_template[] = {
        0xC0                    /*  End Collection                          */
 };
 
+/* Parameter indices */
+enum huion_prm {
+       HUION_PRM_X_LM          = 1,
+       HUION_PRM_Y_LM          = 2,
+       HUION_PRM_PRESSURE_LM   = 4,
+       HUION_PRM_RESOLUTION    = 5,
+       HUION_PRM_NUM
+};
+
 /* Driver data */
 struct huion_drvdata {
        __u8 *rdesc;
@@ -115,7 +124,12 @@ static int huion_tablet_enable(struct hid_device *hdev)
        int rc;
        struct usb_device *usb_dev = hid_to_usb_dev(hdev);
        struct huion_drvdata *drvdata = hid_get_drvdata(hdev);
-       __le16 buf[6];
+       __le16 *buf = NULL;
+       size_t len;
+       s32 params[HUION_PH_ID_NUM];
+       s32 resolution;
+       __u8 *p;
+       s32 v;
 
        /*
         * Read string descriptor containing tablet parameters. The specific
@@ -123,65 +137,79 @@ static int huion_tablet_enable(struct hid_device *hdev)
         * driver traffic.
         * NOTE: This enables fully-functional tablet mode.
         */
+       len = HUION_PRM_NUM * sizeof(*buf);
+       buf = kmalloc(len, GFP_KERNEL);
+       if (buf == NULL) {
+               hid_err(hdev, "failed to allocate parameter buffer\n");
+               rc = -ENOMEM;
+               goto cleanup;
+       }
        rc = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
                                USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
                                (USB_DT_STRING << 8) + 0x64,
-                               0x0409, buf, sizeof(buf),
+                               0x0409, buf, len,
                                USB_CTRL_GET_TIMEOUT);
-       if (rc == -EPIPE)
-               hid_warn(hdev, "device parameters not found\n");
-       else if (rc < 0)
-               hid_warn(hdev, "failed to get device parameters: %d\n", rc);
-       else if (rc != sizeof(buf))
-               hid_warn(hdev, "invalid device parameters\n");
-       else {
-               s32 params[HUION_PH_ID_NUM];
-               s32 resolution;
-               __u8 *p;
-               s32 v;
+       if (rc == -EPIPE) {
+               hid_err(hdev, "device parameters not found\n");
+               rc = -ENODEV;
+               goto cleanup;
+       } else if (rc < 0) {
+               hid_err(hdev, "failed to get device parameters: %d\n", rc);
+               rc = -ENODEV;
+               goto cleanup;
+       } else if (rc != len) {
+               hid_err(hdev, "invalid device parameters\n");
+               rc = -ENODEV;
+               goto cleanup;
+       }
 
-               /* Extract device parameters */
-               params[HUION_PH_ID_X_LM] = le16_to_cpu(buf[1]);
-               params[HUION_PH_ID_Y_LM] = le16_to_cpu(buf[2]);
-               params[HUION_PH_ID_PRESSURE_LM] = le16_to_cpu(buf[4]);
-               resolution = le16_to_cpu(buf[5]);
-               if (resolution == 0) {
-                       params[HUION_PH_ID_X_PM] = 0;
-                       params[HUION_PH_ID_Y_PM] = 0;
-               } else {
-                       params[HUION_PH_ID_X_PM] = params[HUION_PH_ID_X_LM] *
-                                                       1000 / resolution;
-                       params[HUION_PH_ID_Y_PM] = params[HUION_PH_ID_Y_LM] *
-                                                       1000 / resolution;
-               }
+       /* Extract device parameters */
+       params[HUION_PH_ID_X_LM] = le16_to_cpu(buf[HUION_PRM_X_LM]);
+       params[HUION_PH_ID_Y_LM] = le16_to_cpu(buf[HUION_PRM_Y_LM]);
+       params[HUION_PH_ID_PRESSURE_LM] =
+               le16_to_cpu(buf[HUION_PRM_PRESSURE_LM]);
+       resolution = le16_to_cpu(buf[HUION_PRM_RESOLUTION]);
+       if (resolution == 0) {
+               params[HUION_PH_ID_X_PM] = 0;
+               params[HUION_PH_ID_Y_PM] = 0;
+       } else {
+               params[HUION_PH_ID_X_PM] = params[HUION_PH_ID_X_LM] *
+                                               1000 / resolution;
+               params[HUION_PH_ID_Y_PM] = params[HUION_PH_ID_Y_LM] *
+                                               1000 / resolution;
+       }
 
-               /* Allocate fixed report descriptor */
-               drvdata->rdesc = devm_kmalloc(&hdev->dev,
-                                       sizeof(huion_tablet_rdesc_template),
-                                       GFP_KERNEL);
-               if (drvdata->rdesc == NULL) {
-                       hid_err(hdev, "failed to allocate fixed rdesc\n");
-                       return -ENOMEM;
-               }
-               drvdata->rsize = sizeof(huion_tablet_rdesc_template);
+       /* Allocate fixed report descriptor */
+       drvdata->rdesc = devm_kmalloc(&hdev->dev,
+                               sizeof(huion_tablet_rdesc_template),
+                               GFP_KERNEL);
+       if (drvdata->rdesc == NULL) {
+               hid_err(hdev, "failed to allocate fixed rdesc\n");
+               rc = -ENOMEM;
+               goto cleanup;
+       }
+       drvdata->rsize = sizeof(huion_tablet_rdesc_template);
 
-               /* Format fixed report descriptor */
-               memcpy(drvdata->rdesc, huion_tablet_rdesc_template,
-                       drvdata->rsize);
-               for (p = drvdata->rdesc;
-                    p <= drvdata->rdesc + drvdata->rsize - 4;) {
-                       if (p[0] == 0xFE && p[1] == 0xED && p[2] == 0x1D &&
-                           p[3] < sizeof(params)) {
-                               v = params[p[3]];
-                               put_unaligned(cpu_to_le32(v), (s32 *)p);
-                               p += 4;
-                       } else {
-                               p++;
-                       }
+       /* Format fixed report descriptor */
+       memcpy(drvdata->rdesc, huion_tablet_rdesc_template,
+               drvdata->rsize);
+       for (p = drvdata->rdesc;
+            p <= drvdata->rdesc + drvdata->rsize - 4;) {
+               if (p[0] == 0xFE && p[1] == 0xED && p[2] == 0x1D &&
+                   p[3] < sizeof(params)) {
+                       v = params[p[3]];
+                       put_unaligned(cpu_to_le32(v), (s32 *)p);
+                       p += 4;
+               } else {
+                       p++;
                }
        }
 
-       return 0;
+       rc = 0;
+
+cleanup:
+       kfree(buf);
+       return rc;
 }
 
 static int huion_probe(struct hid_device *hdev, const struct hid_device_id *id)