HID: huion: Switch to generating report descriptor
Switch to generating tablet pen report descriptor from a template and
parameters retrieved from string descriptor 0x64.
Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-huion.c b/drivers/hid/hid-huion.c
index 46c425b..6c811c1 100644
--- a/drivers/hid/hid-huion.c
+++ b/drivers/hid/hid-huion.c
@@ -16,67 +16,89 @@
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/usb.h>
+#include <asm/unaligned.h>
#include "usbhid/usbhid.h"
#include "hid-ids.h"
-/* Original tablet report descriptor size */
-#define HUION_TABLET_RDESC_ORIG_SIZE 177
+/* Report descriptor template placeholder head */
+#define HUION_PH_HEAD 0xFE, 0xED, 0x1D
-/* Fixed tablet report descriptor */
-static __u8 huion_tablet_rdesc_fixed[] = {
- 0x05, 0x0D, /* Usage Page (Digitizer), */
- 0x09, 0x02, /* Usage (Pen), */
- 0xA1, 0x01, /* Collection (Application), */
- 0x85, 0x07, /* Report ID (7), */
- 0x09, 0x20, /* Usage (Stylus), */
- 0xA0, /* Collection (Physical), */
- 0x14, /* Logical Minimum (0), */
- 0x25, 0x01, /* Logical Maximum (1), */
- 0x75, 0x01, /* Report Size (1), */
- 0x09, 0x42, /* Usage (Tip Switch), */
- 0x09, 0x44, /* Usage (Barrel Switch), */
- 0x09, 0x46, /* Usage (Tablet Pick), */
- 0x95, 0x03, /* Report Count (3), */
- 0x81, 0x02, /* Input (Variable), */
- 0x95, 0x03, /* Report Count (3), */
- 0x81, 0x03, /* Input (Constant, Variable), */
- 0x09, 0x32, /* Usage (In Range), */
- 0x95, 0x01, /* Report Count (1), */
- 0x81, 0x02, /* Input (Variable), */
- 0x95, 0x01, /* Report Count (1), */
- 0x81, 0x03, /* Input (Constant, Variable), */
- 0x75, 0x10, /* Report Size (16), */
- 0x95, 0x01, /* Report Count (1), */
- 0xA4, /* Push, */
- 0x05, 0x01, /* Usage Page (Desktop), */
- 0x65, 0x13, /* Unit (Inch), */
- 0x55, 0xFD, /* Unit Exponent (-3), */
- 0x34, /* Physical Minimum (0), */
- 0x09, 0x30, /* Usage (X), */
- 0x46, 0x40, 0x1F, /* Physical Maximum (8000), */
- 0x26, 0x00, 0x7D, /* Logical Maximum (32000), */
- 0x81, 0x02, /* Input (Variable), */
- 0x09, 0x31, /* Usage (Y), */
- 0x46, 0x88, 0x13, /* Physical Maximum (5000), */
- 0x26, 0x20, 0x4E, /* Logical Maximum (20000), */
- 0x81, 0x02, /* Input (Variable), */
- 0xB4, /* Pop, */
- 0x09, 0x30, /* Usage (Tip Pressure), */
- 0x26, 0xFF, 0x07, /* Logical Maximum (2047), */
- 0x81, 0x02, /* Input (Variable), */
- 0xC0, /* End Collection, */
- 0xC0 /* End Collection */
+/* Report descriptor template placeholder IDs */
+enum huion_ph_id {
+ HUION_PH_ID_X_LM,
+ HUION_PH_ID_X_PM,
+ HUION_PH_ID_Y_LM,
+ HUION_PH_ID_Y_PM,
+ HUION_PH_ID_PRESSURE_LM,
+ HUION_PH_ID_NUM
+};
+
+/* Report descriptor template placeholder */
+#define HUION_PH(_ID) HUION_PH_HEAD, HUION_PH_ID_##_ID
+
+/* Fixed report descriptor template */
+static const __u8 huion_tablet_rdesc_template[] = {
+ 0x05, 0x0D, /* Usage Page (Digitizer), */
+ 0x09, 0x02, /* Usage (Pen), */
+ 0xA1, 0x01, /* Collection (Application), */
+ 0x85, 0x07, /* Report ID (7), */
+ 0x09, 0x20, /* Usage (Stylus), */
+ 0xA0, /* Collection (Physical), */
+ 0x14, /* Logical Minimum (0), */
+ 0x25, 0x01, /* Logical Maximum (1), */
+ 0x75, 0x01, /* Report Size (1), */
+ 0x09, 0x42, /* Usage (Tip Switch), */
+ 0x09, 0x44, /* Usage (Barrel Switch), */
+ 0x09, 0x46, /* Usage (Tablet Pick), */
+ 0x95, 0x03, /* Report Count (3), */
+ 0x81, 0x02, /* Input (Variable), */
+ 0x95, 0x03, /* Report Count (3), */
+ 0x81, 0x03, /* Input (Constant, Variable), */
+ 0x09, 0x32, /* Usage (In Range), */
+ 0x95, 0x01, /* Report Count (1), */
+ 0x81, 0x02, /* Input (Variable), */
+ 0x95, 0x01, /* Report Count (1), */
+ 0x81, 0x03, /* Input (Constant, Variable), */
+ 0x75, 0x10, /* Report Size (16), */
+ 0x95, 0x01, /* Report Count (1), */
+ 0xA4, /* Push, */
+ 0x05, 0x01, /* Usage Page (Desktop), */
+ 0x65, 0x13, /* Unit (Inch), */
+ 0x55, 0xFD, /* Unit Exponent (-3), */
+ 0x34, /* Physical Minimum (0), */
+ 0x09, 0x30, /* Usage (X), */
+ 0x27, HUION_PH(X_LM), /* Logical Maximum (PLACEHOLDER), */
+ 0x47, HUION_PH(X_PM), /* Physical Maximum (PLACEHOLDER), */
+ 0x81, 0x02, /* Input (Variable), */
+ 0x09, 0x31, /* Usage (Y), */
+ 0x27, HUION_PH(Y_LM), /* Logical Maximum (PLACEHOLDER), */
+ 0x47, HUION_PH(Y_PM), /* Physical Maximum (PLACEHOLDER), */
+ 0x81, 0x02, /* Input (Variable), */
+ 0xB4, /* Pop, */
+ 0x09, 0x30, /* Usage (Tip Pressure), */
+ 0x27,
+ HUION_PH(PRESSURE_LM), /* Logical Maximum (PLACEHOLDER), */
+ 0x81, 0x02, /* Input (Variable), */
+ 0xC0, /* End Collection, */
+ 0xC0 /* End Collection */
+};
+
+/* Driver data */
+struct huion_drvdata {
+ __u8 *rdesc;
+ unsigned int rsize;
};
static __u8 *huion_report_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
+ struct huion_drvdata *drvdata = hid_get_drvdata(hdev);
switch (hdev->product) {
case USB_DEVICE_ID_HUION_TABLET:
- if (*rsize == HUION_TABLET_RDESC_ORIG_SIZE) {
- rdesc = huion_tablet_rdesc_fixed;
- *rsize = sizeof(huion_tablet_rdesc_fixed);
+ if (drvdata->rdesc != NULL) {
+ rdesc = drvdata->rdesc;
+ *rsize = drvdata->rsize;
}
break;
}
@@ -84,57 +106,124 @@
}
/**
- * Enable fully-functional tablet mode by reading special string
- * descriptor.
+ * Enable fully-functional tablet mode and determine device parameters.
*
* @hdev: HID device
- *
- * The specific string descriptor and data were discovered by sniffing
- * the Windows driver traffic.
*/
static int huion_tablet_enable(struct hid_device *hdev)
{
int rc;
- char buf[22];
+ struct usb_device *usb_dev = hid_to_usb_dev(hdev);
+ struct huion_drvdata *drvdata = hid_get_drvdata(hdev);
+ u16 buf[6];
- rc = usb_string(hid_to_usb_dev(hdev), 0x64, buf, sizeof(buf));
- if (rc < 0)
- return rc;
+ /*
+ * Read string descriptor containing tablet parameters. The specific
+ * string descriptor and data were discovered by sniffing the Windows
+ * driver traffic.
+ * NOTE: This enables fully-functional tablet mode.
+ */
+ 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),
+ 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;
+
+ /* 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;
+ }
+
+ /* 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);
+
+ /* 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;
}
static int huion_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
- int ret;
+ int rc;
+ struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
+ struct huion_drvdata *drvdata;
- ret = hid_parse(hdev);
- if (ret) {
- hid_err(hdev, "parse failed\n");
- goto err;
+ /* Allocate and assign driver data */
+ drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
+ if (drvdata == NULL) {
+ hid_err(hdev, "failed to allocate driver data\n");
+ return -ENOMEM;
}
-
- ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
- if (ret) {
- hid_err(hdev, "hw start failed\n");
- goto err;
- }
+ hid_set_drvdata(hdev, drvdata);
switch (id->product) {
case USB_DEVICE_ID_HUION_TABLET:
- ret = huion_tablet_enable(hdev);
- if (ret) {
- hid_err(hdev, "tablet enabling failed\n");
- goto enabling_err;
+ /* If this is the pen interface */
+ if (intf->cur_altsetting->desc.bInterfaceNumber == 0) {
+ rc = huion_tablet_enable(hdev);
+ if (rc) {
+ hid_err(hdev, "tablet enabling failed\n");
+ return rc;
+ }
}
break;
}
+ rc = hid_parse(hdev);
+ if (rc) {
+ hid_err(hdev, "parse failed\n");
+ return rc;
+ }
+
+ rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+ if (rc) {
+ hid_err(hdev, "hw start failed\n");
+ return rc;
+ }
+
return 0;
-enabling_err:
- hid_hw_stop(hdev);
-err:
- return ret;
}
static int huion_raw_event(struct hid_device *hdev, struct hid_report *report,