// SPDX-License-Identifier: GPL-2.0-only /* * HID driver for ELO usb touchscreen 4000/4500 * * Copyright (c) 2013 Jiri Slaby * * Data parsing taken from elousb driver by Vojtech Pavlik. */ #include <linux/hid.h> #include <linux/input.h> #include <linux/module.h> #include <linux/usb.h> #include <linux/workqueue.h> #include "hid-ids.h" #define ELO_PERIODIC_READ_INTERVAL HZ #define ELO_SMARTSET_CMD_TIMEOUT 2000 /* msec */ /* Elo SmartSet commands */ #define ELO_FLUSH_SMARTSET_RESPONSES 0x02 /* Flush all pending smartset responses */ #define ELO_SEND_SMARTSET_COMMAND 0x05 /* Send a smartset command */ #define ELO_GET_SMARTSET_RESPONSE 0x06 /* Get a smartset response */ #define ELO_DIAG 0x64 /* Diagnostics command */ #define ELO_SMARTSET_PACKET_SIZE 8 struct elo_priv { struct usb_device *usbdev; struct delayed_work work; unsigned char buffer[ELO_SMARTSET_PACKET_SIZE]; }; static struct workqueue_struct *wq; static bool use_fw_quirk = true; module_param(use_fw_quirk, bool, S_IRUGO); MODULE_PARM_DESC(use_fw_quirk, "Do periodic pokes for broken M firmwares (default = true)"); static int elo_input_configured(struct hid_device *hdev, struct hid_input *hidinput) { struct input_dev *input = hidinput->input; /* * ELO devices have one Button usage in GenDesk field, which makes * hid-input map it to BTN_LEFT; that confuses userspace, which then * considers the device to be a mouse/touchpad instead of touchscreen. */ clear_bit(BTN_LEFT, input->keybit); set_bit(BTN_TOUCH, input->keybit); set_bit(ABS_PRESSURE, input->absbit); input_set_abs_params(input, ABS_PRESSURE, 0, 256, 0, 0); return 0; } static void elo_process_data(struct input_dev *input, const u8 *data, int size) { int press; input_report_abs(input, ABS_X, (data[3] << 8) | data[2]); input_report_abs(input, ABS_Y, (data[5] << 8) | data[4]); press = 0; if (data[1] & 0x80) press = (data[7] << 8) | data[6]; input_report_abs(input, ABS_PRESSURE, press); if (data[1] & 0x03) { input_report_key(input, BTN_TOUCH, 1); input_sync(input); } if (data[1] & 0x04) input_report_key(input, BTN_TOUCH, 0); input_sync(input); } static int elo_raw_event(struct hid_device *hdev, struct hid_report *report, u8 *data, int size) { struct hid_input *hidinput; if (!(hdev->claimed & HID_CLAIMED_INPUT) || list_empty(&hdev->inputs)) return 0; hidinput = list_first_entry(&hdev->inputs, struct hid_input, list); switch (report->id) { case 0: if (data[0] == 'T') { /* Mandatory ELO packet marker */ elo_process_data(hidinput->input, data, size); return 1; } break; default: /* unknown report */ /* Unknown report type; pass upstream */ hid_info(hdev, "unknown report type %d\n", report->id); break; } return 0; } static int elo_smartset_send_get(struct usb_device *dev, u8 command, void *data) { unsigned int pipe; u8 dir; if (command == ELO_SEND_SMARTSET_COMMAND) { pipe = usb_sndctrlpipe(dev, 0); dir = USB_DIR_OUT; } else if (command == ELO_GET_SMARTSET_RESPONSE) { pipe = usb_rcvctrlpipe(dev, 0); dir = USB_DIR_IN; } else return -EINVAL; return usb_control_msg(dev, pipe, command, dir | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 0, 0, data, ELO_SMARTSET_PACKET_SIZE, ELO_SMARTSET_CMD_TIMEOUT); } static int elo_flush_smartset_responses(struct usb_device *dev) { return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), ELO_FLUSH_SMARTSET_RESPONSES, USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT); } static void elo_work(struct work_struct *work) { struct elo_priv *priv = container_of(work, struct elo_priv, work.work); struct usb_device *dev = priv->usbdev; unsigned char *buffer = priv->buffer; int ret; ret = elo_flush_smartset_responses(dev); if (ret < 0) { dev_err(&dev->dev, "initial FLUSH_SMARTSET_RESPONSES failed, error %d\n", ret); goto fail; } /* send Diagnostics command */ *buffer = ELO_DIAG; ret = elo_smartset_send_get(dev, ELO_SEND_SMARTSET_COMMAND, buffer); if (ret < 0) { dev_err(&dev->dev, "send Diagnostics Command failed, error %d\n", ret); goto fail; } /* get the result */ ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE, buffer); if (ret < 0) { dev_err(&dev->dev, "get Diagnostics Command response failed, error %d\n", ret); goto fail; } /* read the ack */ if (*buffer != 'A') { ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE, buffer); if (ret < 0) { dev_err(&dev->dev, "get acknowledge response failed, error %d\n", ret); goto fail; } } fail: ret = elo_flush_smartset_responses(dev); if (ret < 0) dev_err(&dev->dev, "final FLUSH_SMARTSET_RESPONSES failed, error %d\n", ret); queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL); } /* * Not all Elo devices need the periodic HID descriptor reads. * Only firmware version M needs this. */ static bool elo_broken_firmware(struct usb_device *dev) { struct usb_device *hub = dev->parent; struct usb_device *child = NULL; u16 fw_lvl = le16_to_cpu(dev->descriptor.bcdDevice); u16 child_vid, child_pid; int i; if (!use_fw_quirk) return false; if (fw_lvl != 0x10d) return false; /* iterate sibling devices of the touch controller */ usb_hub_for_each_child(hub, i, child) { child_vid = le16_to_cpu(child->descriptor.idVendor); child_pid = le16_to_cpu(child->descriptor.idProduct); /* * If one of the devices below is present attached as a sibling of * the touch controller then this is a newer IBM 4820 monitor that * does not need the IBM-requested workaround if fw level is * 0x010d - aka 'M'. * No other HW can have this combination. */ if (child_vid==0x04b3) { switch (child_pid) { case 0x4676: /* 4820 21x Video */ case 0x4677: /* 4820 51x Video */ case 0x4678: /* 4820 2Lx Video */ case 0x4679: /* 4820 5Lx Video */ return false; } } } return true; } static int elo_probe(struct hid_device *hdev, const struct hid_device_id *id) { struct elo_priv *priv; int ret; struct usb_device *udev; priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; INIT_DELAYED_WORK(&priv->work, elo_work); udev = interface_to_usbdev(to_usb_interface(hdev->dev.parent)); priv->usbdev = usb_get_dev(udev); hid_set_drvdata(hdev, priv); ret = hid_parse(hdev); if (ret) { hid_err(hdev, "parse failed\n"); goto err_free; } ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); if (ret) { hid_err(hdev, "hw start failed\n"); goto err_free; } if (elo_broken_firmware(priv->usbdev)) { hid_info(hdev, "broken firmware found, installing workaround\n"); queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL); } return 0; err_free: kfree(priv); return ret; } static void elo_remove(struct hid_device *hdev) { struct elo_priv *priv = hid_get_drvdata(hdev); usb_put_dev(priv->usbdev); hid_hw_stop(hdev); cancel_delayed_work_sync(&priv->work); kfree(priv); } static const struct hid_device_id elo_devices[] = { { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0009), }, { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0030), }, { } }; MODULE_DEVICE_TABLE(hid, elo_devices); static struct hid_driver elo_driver = { .name = "elo", .id_table = elo_devices, .probe = elo_probe, .remove = elo_remove, .raw_event = elo_raw_event, .input_configured = elo_input_configured, }; static int __init elo_driver_init(void) { int ret; wq = create_singlethread_workqueue("elousb"); if (!wq) return -ENOMEM; ret = hid_register_driver(&elo_driver); if (ret) destroy_workqueue(wq); return ret; } module_init(elo_driver_init); static void __exit elo_driver_exit(void) { hid_unregister_driver(&elo_driver); destroy_workqueue(wq); } module_exit(elo_driver_exit); MODULE_AUTHOR("Jiri Slaby <jslaby@suse.cz>"); MODULE_LICENSE("GPL");