diff options
Diffstat (limited to 'drivers/hid/hid-elan.c')
| -rw-r--r-- | drivers/hid/hid-elan.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/drivers/hid/hid-elan.c b/drivers/hid/hid-elan.c new file mode 100644 index 000000000000..803a725785cf --- /dev/null +++ b/drivers/hid/hid-elan.c @@ -0,0 +1,421 @@ +/* + * HID Driver for ELAN Touchpad + * + * Currently only supports touchpad found on HP Pavilion X2 10 + * + * Copyright (c) 2016 Alexandrov Stanislav <neko@nya.ai> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + */ + +#include <linux/hid.h> +#include <linux/input/mt.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/usb.h> + +#include "hid-ids.h" + +#define ELAN_SINGLE_FINGER 0x81 +#define ELAN_MT_FIRST_FINGER 0x82 +#define ELAN_MT_SECOND_FINGER 0x83 +#define ELAN_INPUT_REPORT_SIZE 8 + +#define ELAN_MUTE_LED_REPORT 0xBC +#define ELAN_LED_REPORT_SIZE 8 + +struct elan_touchpad_settings { + u8 max_fingers; + u16 max_x; + u16 max_y; + u8 max_area_x; + u8 max_area_y; + u8 max_w; + int usb_bInterfaceNumber; +}; + +struct elan_drvdata { + struct input_dev *input; + u8 prev_report[ELAN_INPUT_REPORT_SIZE]; + struct led_classdev mute_led; + u8 mute_led_state; + struct elan_touchpad_settings *settings; +}; + +static int is_not_elan_touchpad(struct hid_device *hdev) +{ + struct usb_interface *intf = to_usb_interface(hdev->dev.parent); + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + + return (intf->altsetting->desc.bInterfaceNumber != drvdata->settings->usb_bInterfaceNumber); +} + +static int elan_input_mapping(struct hid_device *hdev, struct hid_input *hi, + struct hid_field *field, struct hid_usage *usage, + unsigned long **bit, int *max) +{ + if (is_not_elan_touchpad(hdev)) + return 0; + + if (field->report->id == ELAN_SINGLE_FINGER || + field->report->id == ELAN_MT_FIRST_FINGER || + field->report->id == ELAN_MT_SECOND_FINGER) + return -1; + + return 0; +} + +static int elan_input_configured(struct hid_device *hdev, struct hid_input *hi) +{ + int ret; + struct input_dev *input; + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + + if (is_not_elan_touchpad(hdev)) + return 0; + + input = devm_input_allocate_device(&hdev->dev); + if (!input) + return -ENOMEM; + + input->name = "Elan Touchpad"; + input->phys = hdev->phys; + input->uniq = hdev->uniq; + input->id.bustype = hdev->bus; + input->id.vendor = hdev->vendor; + input->id.product = hdev->product; + input->id.version = hdev->version; + input->dev.parent = &hdev->dev; + + input_set_abs_params(input, ABS_MT_POSITION_X, 0, + drvdata->settings->max_x, 0, 0); + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, + drvdata->settings->max_y, 0, 0); + input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, + drvdata->settings->max_fingers, 0, 0); + input_set_abs_params(input, ABS_TOOL_WIDTH, 0, + drvdata->settings->max_w, 0, 0); + + __set_bit(BTN_LEFT, input->keybit); + __set_bit(INPUT_PROP_BUTTONPAD, input->propbit); + + ret = input_mt_init_slots(input, drvdata->settings->max_fingers, + INPUT_MT_POINTER); + if (ret) { + hid_err(hdev, "Failed to init elan MT slots: %d\n", ret); + return ret; + } + + ret = input_register_device(input); + if (ret) { + hid_err(hdev, "Failed to register elan input device: %d\n", + ret); + input_free_device(input); + return ret; + } + + drvdata->input = input; + + return 0; +} + +static void elan_report_mt_slot(struct elan_drvdata *drvdata, u8 *data, + unsigned int slot_num) +{ + struct input_dev *input = drvdata->input; + int x, y, w; + + bool active = !!data; + + input_mt_slot(input, slot_num); + input_mt_report_slot_state(input, MT_TOOL_FINGER, active); + if (active) { + x = ((data[0] & 0xF0) << 4) | data[1]; + y = drvdata->settings->max_y - + (((data[0] & 0x07) << 8) | data[2]); + w = data[4]; + + input_report_abs(input, ABS_MT_POSITION_X, x); + input_report_abs(input, ABS_MT_POSITION_Y, y); + input_report_abs(input, ABS_TOOL_WIDTH, w); + } +} + +static void elan_report_input(struct elan_drvdata *drvdata, u8 *data) +{ + int i; + struct input_dev *input = drvdata->input; + + /* + * There is 3 types of reports: for single touch, + * for multitouch - first finger and for multitouch - second finger + * + * packet structure for ELAN_SINGLE_FINGER and ELAN_MT_FIRST_FINGER: + * + * byte 1: 1 0 0 0 0 0 0 1 // 0x81 or 0x82 + * byte 2: 0 0 0 0 0 0 0 0 // looks like unused + * byte 3: f5 f4 f3 f2 f1 0 0 L + * byte 4: x12 x11 x10 x9 0? y11 y10 y9 + * byte 5: x8 x7 x6 x5 x4 x3 x2 x1 + * byte 6: y8 y7 y6 y5 y4 y3 y2 y1 + * byte 7: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1 + * byte 8: w8 w7 w6 w5 w4 w3 w2 w1 + * + * packet structure for ELAN_MT_SECOND_FINGER: + * + * byte 1: 1 0 0 0 0 0 1 1 // 0x83 + * byte 2: x12 x11 x10 x9 0 y11 y10 y9 + * byte 3: x8 x7 x6 x5 x4 x3 x2 x1 + * byte 4: y8 y7 y6 y5 y4 y3 y2 y1 + * byte 5: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1 + * byte 6: w8 w7 w6 w5 w4 w3 w2 w1 + * byte 7: 0 0 0 0 0 0 0 0 + * byte 8: 0 0 0 0 0 0 0 0 + * + * f5-f1: finger touch bits + * L: clickpad button + * sy / sx: not sure yet, but this looks like rectangular + * area for finger + * w: looks like finger width + */ + + if (data[0] == ELAN_SINGLE_FINGER) { + for (i = 0; i < drvdata->settings->max_fingers; i++) { + if (data[2] & BIT(i + 3)) + elan_report_mt_slot(drvdata, data + 3, i); + else + elan_report_mt_slot(drvdata, NULL, i); + } + input_report_key(input, BTN_LEFT, data[2] & 0x01); + } + /* + * When touched with two fingers Elan touchpad will emit two HID reports + * first is ELAN_MT_FIRST_FINGER and second is ELAN_MT_SECOND_FINGER + * we will save ELAN_MT_FIRST_FINGER report and wait for + * ELAN_MT_SECOND_FINGER to finish multitouch + */ + if (data[0] == ELAN_MT_FIRST_FINGER) { + memcpy(drvdata->prev_report, data, + sizeof(drvdata->prev_report)); + return; + } + + if (data[0] == ELAN_MT_SECOND_FINGER) { + int first = 0; + u8 *prev_report = drvdata->prev_report; + + if (prev_report[0] != ELAN_MT_FIRST_FINGER) + return; + + for (i = 0; i < drvdata->settings->max_fingers; i++) { + if (prev_report[2] & BIT(i + 3)) { + if (!first) { + first = 1; + elan_report_mt_slot(drvdata, prev_report + 3, i); + } else { + elan_report_mt_slot(drvdata, data + 1, i); + } + } else { + elan_report_mt_slot(drvdata, NULL, i); + } + } + input_report_key(input, BTN_LEFT, prev_report[2] & 0x01); + } + + input_mt_sync_frame(input); + input_sync(input); +} + +static int elan_raw_event(struct hid_device *hdev, + struct hid_report *report, u8 *data, int size) +{ + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + + if (is_not_elan_touchpad(hdev)) + return 0; + + if (data[0] == ELAN_SINGLE_FINGER || + data[0] == ELAN_MT_FIRST_FINGER || + data[0] == ELAN_MT_SECOND_FINGER) { + if (size == ELAN_INPUT_REPORT_SIZE) { + elan_report_input(drvdata, data); + return 1; + } + } + + return 0; +} + +static int elan_start_multitouch(struct hid_device *hdev) +{ + int ret; + + /* + * This byte sequence will enable multitouch mode and disable + * mouse emulation + */ + const unsigned char buf[] = { 0x0D, 0x00, 0x03, 0x21, 0x00 }; + unsigned char *dmabuf = kmemdup(buf, sizeof(buf), GFP_KERNEL); + + if (!dmabuf) + return -ENOMEM; + + 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, "Failed to start multitouch: %d\n", ret); + return ret; + } + + return 0; +} + +static enum led_brightness elan_mute_led_get_brigtness(struct led_classdev *led_cdev) +{ + struct device *dev = led_cdev->dev->parent; + struct hid_device *hdev = to_hid_device(dev); + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + + return drvdata->mute_led_state; +} + +static int elan_mute_led_set_brigtness(struct led_classdev *led_cdev, + enum led_brightness value) +{ + int ret; + u8 led_state; + struct device *dev = led_cdev->dev->parent; + struct hid_device *hdev = to_hid_device(dev); + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + + unsigned char *dmabuf = kzalloc(ELAN_LED_REPORT_SIZE, GFP_KERNEL); + + if (!dmabuf) + return -ENOMEM; + + led_state = !!value; + + dmabuf[0] = ELAN_MUTE_LED_REPORT; + dmabuf[1] = 0x02; + dmabuf[2] = led_state; + + ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, ELAN_LED_REPORT_SIZE, + HID_FEATURE_REPORT, HID_REQ_SET_REPORT); + + kfree(dmabuf); + + if (ret != ELAN_LED_REPORT_SIZE) { + hid_err(hdev, "Failed to set mute led brightness: %d\n", ret); + return ret; + } + + drvdata->mute_led_state = led_state; + return 0; +} + +static int elan_init_mute_led(struct hid_device *hdev) +{ + struct elan_drvdata *drvdata = hid_get_drvdata(hdev); + struct led_classdev *mute_led = &drvdata->mute_led; + + mute_led->name = "elan:red:mute"; + mute_led->brightness_get = elan_mute_led_get_brigtness; + mute_led->brightness_set_blocking = elan_mute_led_set_brigtness; + mute_led->max_brightness = LED_ON; + mute_led->dev = &hdev->dev; + + return devm_led_classdev_register(&hdev->dev, mute_led); +} + +static int elan_probe(struct hid_device *hdev, const struct hid_device_id *id) +{ + int ret; + struct elan_drvdata *drvdata; + + drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL); + + if (!drvdata) + return -ENOMEM; + + drvdata->settings = (struct elan_touchpad_settings *)id->driver_data; + hid_set_drvdata(hdev, drvdata); + + ret = hid_parse(hdev); + if (ret) { + hid_err(hdev, "Hid Parse failed\n"); + return ret; + } + + ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); + if (ret) { + hid_err(hdev, "Hid hw start failed\n"); + return ret; + } + + if (is_not_elan_touchpad(hdev)) + return 0; + + if (!drvdata->input) { + hid_err(hdev, "Input device is not registred\n"); + ret = -ENAVAIL; + goto err; + } + + ret = elan_start_multitouch(hdev); + if (ret) + goto err; + + ret = elan_init_mute_led(hdev); + if (ret) + goto err; + + return 0; +err: + hid_hw_stop(hdev); + return ret; +} + +static void elan_remove(struct hid_device *hdev) +{ + hid_hw_stop(hdev); +} + +static const struct elan_touchpad_settings hp_x2_10_touchpad_data = { + .max_fingers = 5, + .max_x = 2930, + .max_y = 1250, + .max_area_x = 15, + .max_area_y = 15, + .max_w = 255, + .usb_bInterfaceNumber = 1, +}; + +static const struct hid_device_id elan_devices[] = { + { HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_HP_X2_10_COVER), + (kernel_ulong_t)&hp_x2_10_touchpad_data}, + { } +}; + +MODULE_DEVICE_TABLE(hid, elan_devices); + +static struct hid_driver elan_driver = { + .name = "elan", + .id_table = elan_devices, + .input_mapping = elan_input_mapping, + .input_configured = elan_input_configured, + .raw_event = elan_raw_event, + .probe = elan_probe, + .remove = elan_remove, +}; + +module_hid_driver(elan_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexandrov Stanislav"); +MODULE_DESCRIPTION("Driver for HID ELAN Touchpads"); |
