HID: asus: Add i2c touchpad support

Update the hid-asus module to add multitouch support for the Asus i2c touchpad.

This patch aims to resolve the issue raised here:
https://bugzilla.kernel.org/show_bug.cgi?id=120181

The issue is in relation to an Asus touchpad device which currently does not
have multitouch support.

The device currently falls through to the hid-generic driver which
treats the device as a mouse.

This patch aims to add the multitouch support.

[jkosina@suse.cz: move most of the 'patch comment' into actual changelog]
[jkosina@suse.cz: drop hunk that changes ->name of the driver]
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Brendan McGrath <redmcg@redmandi.dyndns.org>
Signed-off-by: Victor Vlasenko <victor.vlasenko@sysgears.com>
Signed-off-by: Frederik Wenigwieser <frederik.wenigwieser@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

4 files changed, 296 insertions, 7 deletions

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index cd4599c0523b..f8f251c20e2d 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -138,7 +138,7 @@ config HID_ASUS
         tristate "Asus"
         depends on I2C_HID
         ---help---
-        Support for Asus notebook built-in keyboard via i2c.
+        Support for Asus notebook built-in keyboard and touchpad via i2c.
 
         Supported devices:
         - EeeBook X205TA
diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index 7a811ec4f2e1..d40ed9fdf68d 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -11,6 +11,12 @@
  *  This module based on hid-ortek by
  *  Copyright (c) 2010 Johnathon Harris <jmharris@gmail.com>
  *  Copyright (c) 2011 Jiri Kosina
+ *
+ *  This module has been updated to add support for Asus i2c touchpad.
+ *
+ *  Copyright (c) 2016 Brendan McGrath <redmcg@redmandi.dyndns.org>
+ *  Copyright (c) 2016 Victor Vlasenko <victor.vlasenko@sysgears.com>
+ *  Copyright (c) 2016 Frederik Wenigwieser <frederik.wenigwieser@gmail.com>
  */
 
 /*
@@ -20,16 +26,287 @@
  * any later version.
  */
 
-#include <linux/device.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/input/mt.h>
 
 #include "hid-ids.h"
 
+MODULE_AUTHOR("Yusuke Fujimaki <usk.fujimaki@gmail.com>");
+MODULE_AUTHOR("Brendan McGrath <redmcg@redmandi.dyndns.org>");
+MODULE_AUTHOR("Victor Vlasenko <victor.vlasenko@sysgears.com>");
+MODULE_AUTHOR("Frederik Wenigwieser <frederik.wenigwieser@gmail.com>");
+MODULE_DESCRIPTION("Asus HID Keyboard and TouchPad");
+
+#define FEATURE_REPORT_ID 0x0d
+#define INPUT_REPORT_ID 0x5d
+
+#define INPUT_REPORT_SIZE 28
+
+#define MAX_CONTACTS 5
+
+#define MAX_X 2794
+#define MAX_Y 1758
+#define MAX_TOUCH_MAJOR 8
+#define MAX_PRESSURE 128
+
+#define CONTACT_DATA_SIZE 5
+
+#define BTN_LEFT_MASK 0x01
+#define CONTACT_TOOL_TYPE_MASK 0x80
+#define CONTACT_X_MSB_MASK 0xf0
+#define CONTACT_Y_MSB_MASK 0x0f
+#define CONTACT_TOUCH_MAJOR_MASK 0x07
+#define CONTACT_PRESSURE_MASK 0x7f
+
+#define QUIRK_FIX_NOTEBOOK_REPORT       BIT(0)
+#define QUIRK_NO_INIT_REPORTS           BIT(1)
+#define QUIRK_SKIP_INPUT_MAPPING        BIT(2)
+#define QUIRK_IS_MULTITOUCH             BIT(3)
+
+#define NOTEBOOK_QUIRKS                 QUIRK_FIX_NOTEBOOK_REPORT
+#define TOUCHPAD_QUIRKS                 (QUIRK_NO_INIT_REPORTS | \
+                                                 QUIRK_SKIP_INPUT_MAPPING | \
+                                                 QUIRK_IS_MULTITOUCH)
+
+#define TRKID_SGN       ((TRKID_MAX + 1) >> 1)
+
+struct asus_drvdata {
+        unsigned long quirks;
+        struct input_dev *input;
+};
+
+static void asus_report_contact_down(struct input_dev *input,
+                int toolType, u8 *data)
+{
+        int touch_major, pressure;
+        int x = (data[0] & CONTACT_X_MSB_MASK) << 4 | data[1];
+        int y = MAX_Y - ((data[0] & CONTACT_Y_MSB_MASK) << 8 | data[2]);
+
+        if (toolType == MT_TOOL_PALM) {
+                touch_major = MAX_TOUCH_MAJOR;
+                pressure = MAX_PRESSURE;
+        } else {
+                touch_major = (data[3] >> 4) & CONTACT_TOUCH_MAJOR_MASK;
+                pressure = data[4] & CONTACT_PRESSURE_MASK;
+        }
+
+        input_report_abs(input, ABS_MT_POSITION_X, x);
+        input_report_abs(input, ABS_MT_POSITION_Y, y);
+        input_report_abs(input, ABS_MT_TOUCH_MAJOR, touch_major);
+        input_report_abs(input, ABS_MT_PRESSURE, pressure);
+}
+
+/* Required for Synaptics Palm Detection */
+static void asus_report_tool_width(struct input_dev *input)
+{
+        struct input_mt *mt = input->mt;
+        struct input_mt_slot *oldest;
+        int oldid, count, i;
+
+        oldest = NULL;
+        oldid = mt->trkid;
+        count = 0;
+
+        for (i = 0; i < mt->num_slots; ++i) {
+                struct input_mt_slot *ps = &mt->slots[i];
+                int id = input_mt_get_value(ps, ABS_MT_TRACKING_ID);
+
+                if (id < 0)
+                        continue;
+                if ((id - oldid) & TRKID_SGN) {
+                        oldest = ps;
+                        oldid = id;
+                }
+                count++;
+        }
+
+        if (oldest) {
+                input_report_abs(input, ABS_TOOL_WIDTH,
+                        input_mt_get_value(oldest, ABS_MT_TOUCH_MAJOR));
+        }
+}
+
+static void asus_report_input(struct input_dev *input, u8 *data)
+{
+        int i;
+        u8 *contactData = data + 2;
+
+        for (i = 0; i < MAX_CONTACTS; i++) {
+                bool down = !!(data[1] & BIT(i+3));
+                int toolType = contactData[3] & CONTACT_TOOL_TYPE_MASK ?
+                                                MT_TOOL_PALM : MT_TOOL_FINGER;
+
+                input_mt_slot(input, i);
+                input_mt_report_slot_state(input, toolType, down);
+
+                if (down) {
+                        asus_report_contact_down(input, toolType, contactData);
+                        contactData += CONTACT_DATA_SIZE;
+                }
+        }
+
+        input_report_key(input, BTN_LEFT, data[1] & BTN_LEFT_MASK);
+        asus_report_tool_width(input);
+
+        input_mt_sync_frame(input);
+        input_sync(input);
+}
+
+static int asus_raw_event(struct hid_device *hdev,
+                struct hid_report *report, u8 *data, int size)
+{
+        struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+        if (drvdata->quirks & QUIRK_IS_MULTITOUCH &&
+                                         data[0] == INPUT_REPORT_ID &&
+                                                size == INPUT_REPORT_SIZE) {
+                asus_report_input(drvdata->input, data);
+                return 1;
+        }
+
+        return 0;
+}
+
+static int asus_input_configured(struct hid_device *hdev, struct hid_input *hi)
+{
+        struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+        if (drvdata->quirks & QUIRK_IS_MULTITOUCH) {
+                int ret;
+                struct input_dev *input = hi->input;
+
+                input_set_abs_params(input, ABS_MT_POSITION_X, 0, MAX_X, 0, 0);
+                input_set_abs_params(input, ABS_MT_POSITION_Y, 0, MAX_Y, 0, 0);
+                input_set_abs_params(input, ABS_TOOL_WIDTH, 0, MAX_TOUCH_MAJOR, 0, 0);
+                input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, MAX_TOUCH_MAJOR, 0, 0);
+                input_set_abs_params(input, ABS_MT_PRESSURE, 0, MAX_PRESSURE, 0, 0);
+
+                __set_bit(BTN_LEFT, input->keybit);
+                __set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
+
+                ret = input_mt_init_slots(input, MAX_CONTACTS, INPUT_MT_POINTER);
+
+                if (ret) {
+                        hid_err(hdev, "Asus input mt init slots failed: %d\n", ret);
+                        return ret;
+                }
+
+                drvdata->input = input;
+        }
+
+        return 0;
+}
+
+static int asus_input_mapping(struct hid_device *hdev,
+                struct hid_input *hi, struct hid_field *field,
+                struct hid_usage *usage, unsigned long **bit,
+                int *max)
+{
+        struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+        if (drvdata->quirks & QUIRK_SKIP_INPUT_MAPPING) {
+                /* Don't map anything from the HID report.
+                 * We do it all manually in asus_input_configured
+                 */
+                return -1;
+        }
+
+        return 0;
+}
+
+static int asus_start_multitouch(struct hid_device *hdev)
+{
+        int ret;
+        const unsigned char buf[] = { FEATURE_REPORT_ID, 0x00, 0x03, 0x01, 0x00 };
+        unsigned char *dmabuf = kmemdup(buf, sizeof(buf), GFP_KERNEL);
+
+        if (!dmabuf) {
+                ret = -ENOMEM;
+                hid_err(hdev, "Asus failed to alloc dma buf: %d\n", ret);
+                return ret;
+        }
+
+        ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, sizeof(buf),
+                                        HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+
+        kfree(dmabuf);
+
+        if (ret != sizeof(buf)) {
+                hid_err(hdev, "Asus failed to start multitouch: %d\n", ret);
+                return ret;
+        }
+
+        return 0;
+}
+
+static int __maybe_unused asus_reset_resume(struct hid_device *hdev)
+{
+        struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+        if (drvdata->quirks & QUIRK_IS_MULTITOUCH)
+                return asus_start_multitouch(hdev);
+
+        return 0;
+}
+
+static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+        int ret;
+        struct asus_drvdata *drvdata;
+
+        drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
+        if (drvdata == NULL) {
+                hid_err(hdev, "Can't alloc Asus descriptor\n");
+                return -ENOMEM;
+        }
+
+        hid_set_drvdata(hdev, drvdata);
+
+        drvdata->quirks = id->driver_data;
+
+        if (drvdata->quirks & QUIRK_NO_INIT_REPORTS)
+                hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
+
+        ret = hid_parse(hdev);
+        if (ret) {
+                hid_err(hdev, "Asus hid parse failed: %d\n", ret);
+                return ret;
+        }
+
+        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+        if (ret) {
+                hid_err(hdev, "Asus hw start failed: %d\n", ret);
+                return ret;
+        }
+
+        if (!drvdata->input) {
+                hid_err(hdev, "Asus input not registered\n");
+                ret = -ENOMEM;
+                goto err_stop_hw;
+        }
+
+        drvdata->input->name = "Asus TouchPad";
+
+        if (drvdata->quirks & QUIRK_IS_MULTITOUCH) {
+                ret = asus_start_multitouch(hdev);
+                if (ret)
+                        goto err_stop_hw;
+        }
+
+        return 0;
+err_stop_hw:
+        hid_hw_stop(hdev);
+        return ret;
+}
+
 static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
                 unsigned int *rsize)
 {
-        if (*rsize >= 56 && rdesc[54] == 0x25 && rdesc[55] == 0x65) {
+        struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+
+        if (drvdata->quirks & QUIRK_FIX_NOTEBOOK_REPORT &&
+                        *rsize >= 56 && rdesc[54] == 0x25 && rdesc[55] == 0x65) {
                 hid_info(hdev, "Fixing up Asus notebook report descriptor\n");
                 rdesc[55] = 0xdd;
         }
@@ -37,15 +314,25 @@ static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 }
 
 static const struct hid_device_id asus_devices[] = {
-        { HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD) },
+        { HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK,
+                 USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD), NOTEBOOK_QUIRKS},
+        { HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK,
+                         USB_DEVICE_ID_ASUSTEK_TOUCHPAD), TOUCHPAD_QUIRKS },
         { }
 };
 MODULE_DEVICE_TABLE(hid, asus_devices);
 
 static struct hid_driver asus_driver = {
-        .name = "asus",
-        .id_table = asus_devices,
-        .report_fixup = asus_report_fixup
+        .name                   = "asus",
+        .id_table               = asus_devices,
+        .report_fixup           = asus_report_fixup,
+        .probe                  = asus_probe,
+        .input_mapping          = asus_input_mapping,
+        .input_configured       = asus_input_configured,
+#ifdef CONFIG_PM
+        .reset_resume           = asus_reset_resume,
+#endif
+        .raw_event              = asus_raw_event
 };
 module_hid_driver(asus_driver);
 
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 2b89c701076f..689cd9cf5025 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1857,6 +1857,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
         { HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_FOUNTAIN_TP_ONLY) },
         { HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_GEYSER1_TP_ONLY) },
         { HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD) },
+        { HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_TOUCHPAD) },
         { HID_USB_DEVICE(USB_VENDOR_ID_AUREAL, USB_DEVICE_ID_AUREAL_W01RN) },
         { HID_USB_DEVICE(USB_VENDOR_ID_BELKIN, USB_DEVICE_ID_FLIP_KVM) },
         { HID_USB_DEVICE(USB_VENDOR_ID_BETOP_2185BFM, 0x2208) },
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 575aa65436d1..b531bd408f93 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -171,6 +171,7 @@
 #define USB_DEVICE_ID_ASUSTEK_LCM       0x1726
 #define USB_DEVICE_ID_ASUSTEK_LCM2      0x175b
 #define USB_DEVICE_ID_ASUSTEK_NOTEBOOK_KEYBOARD 0x8585
+#define USB_DEVICE_ID_ASUSTEK_TOUCHPAD  0x0101
 
 #define USB_VENDOR_ID_ATEN              0x0557
 #define USB_DEVICE_ID_ATEN_UC100KM      0x2004