drivers/hid/hid-elo.c

   1 /*
   2  * HID driver for ELO usb touchscreen 4000/4500
   3  *
   4  * Copyright (c) 2013 Jiri Slaby
   5  *
   6  * Data parsing taken from elousb driver by Vojtech Pavlik.
   7  *
   8  * This driver is licensed under the terms of GPLv2.
   9  */
  10
  11 #include <linux/hid.h>
  12 #include <linux/input.h>
  13 #include <linux/module.h>
  14 #include <linux/usb.h>
  15 #include <linux/workqueue.h>
  16
  17 #include "hid-ids.h"
  18
  19 #define ELO_PERIODIC_READ_INTERVAL      HZ
  20 #define ELO_SMARTSET_CMD_TIMEOUT        2000 /* msec */
  21
  22 /* Elo SmartSet commands */
  23 #define ELO_FLUSH_SMARTSET_RESPONSES    0x02 /* Flush all pending smartset responses */
  24 #define ELO_SEND_SMARTSET_COMMAND       0x05 /* Send a smartset command */
  25 #define ELO_GET_SMARTSET_RESPONSE       0x06 /* Get a smartset response */
  26 #define ELO_DIAG                        0x64 /* Diagnostics command */
  27 #define ELO_SMARTSET_PACKET_SIZE        8
  28
  29 struct elo_priv {
  30         struct usb_device *usbdev;
  31         struct delayed_work work;
  32         unsigned char buffer[ELO_SMARTSET_PACKET_SIZE];
  33 };
  34
  35 static struct workqueue_struct *wq;
  36 static bool use_fw_quirk = true;
  37 module_param(use_fw_quirk, bool, S_IRUGO);
  38 MODULE_PARM_DESC(use_fw_quirk, "Do periodic pokes for broken M firmwares (default = true)");
  39
  40 static int elo_input_configured(struct hid_device *hdev,
  41                 struct hid_input *hidinput)
  42 {
  43         struct input_dev *input = hidinput->input;
  44
  45         /*
  46          * ELO devices have one Button usage in GenDesk field, which makes
  47          * hid-input map it to BTN_LEFT; that confuses userspace, which then
  48          * considers the device to be a mouse/touchpad instead of touchscreen.
  49          */
  50         clear_bit(BTN_LEFT, input->keybit);
  51         set_bit(BTN_TOUCH, input->keybit);
  52         set_bit(ABS_PRESSURE, input->absbit);
  53         input_set_abs_params(input, ABS_PRESSURE, 0, 256, 0, 0);
  54
  55         return 0;
  56 }
  57
  58 static void elo_process_data(struct input_dev *input, const u8 *data, int size)
  59 {
  60         int press;
  61
  62         input_report_abs(input, ABS_X, (data[3] << 8) | data[2]);
  63         input_report_abs(input, ABS_Y, (data[5] << 8) | data[4]);
  64
  65         press = 0;
  66         if (data[1] & 0x80)
  67                 press = (data[7] << 8) | data[6];
  68         input_report_abs(input, ABS_PRESSURE, press);
  69
  70         if (data[1] & 0x03) {
  71                 input_report_key(input, BTN_TOUCH, 1);
  72                 input_sync(input);
  73         }
  74
  75         if (data[1] & 0x04)
  76                 input_report_key(input, BTN_TOUCH, 0);
  77
  78         input_sync(input);
  79 }
  80
  81 static int elo_raw_event(struct hid_device *hdev, struct hid_report *report,
  82          u8 *data, int size)
  83 {
  84         struct hid_input *hidinput;
  85
  86         if (!(hdev->claimed & HID_CLAIMED_INPUT) || list_empty(&hdev->inputs))
  87                 return 0;
  88
  89         hidinput = list_first_entry(&hdev->inputs, struct hid_input, list);
  90
  91         switch (report->id) {
  92         case 0:
  93                 if (data[0] == 'T') {   /* Mandatory ELO packet marker */
  94                         elo_process_data(hidinput->input, data, size);
  95                         return 1;
  96                 }
  97                 break;
  98         default:        /* unknown report */
  99                 /* Unknown report type; pass upstream */
 100                 hid_info(hdev, "unknown report type %d\n", report->id);
 101                 break;
 102         }
 103
 104         return 0;
 105 }
 106
 107 static int elo_smartset_send_get(struct usb_device *dev, u8 command,
 108                 void *data)
 109 {
 110         unsigned int pipe;
 111         u8 dir;
 112
 113         if (command == ELO_SEND_SMARTSET_COMMAND) {
 114                 pipe = usb_sndctrlpipe(dev, 0);
 115                 dir = USB_DIR_OUT;
 116         } else if (command == ELO_GET_SMARTSET_RESPONSE) {
 117                 pipe = usb_rcvctrlpipe(dev, 0);
 118                 dir = USB_DIR_IN;
 119         } else
 120                 return -EINVAL;
 121
 122         return usb_control_msg(dev, pipe, command,
 123                         dir | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 124                         0, 0, data, ELO_SMARTSET_PACKET_SIZE,
 125                         ELO_SMARTSET_CMD_TIMEOUT);
 126 }
 127
 128 static int elo_flush_smartset_responses(struct usb_device *dev)
 129 {
 130         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 131                         ELO_FLUSH_SMARTSET_RESPONSES,
 132                         USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 133                         0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
 134 }
 135
 136 static void elo_work(struct work_struct *work)
 137 {
 138         struct elo_priv *priv = container_of(work, struct elo_priv, work.work);
 139         struct usb_device *dev = priv->usbdev;
 140         unsigned char *buffer = priv->buffer;
 141         int ret;
 142
 143         ret = elo_flush_smartset_responses(dev);
 144         if (ret < 0) {
 145                 dev_err(&dev->dev, "initial FLUSH_SMARTSET_RESPONSES failed, error %d\n",
 146                                 ret);
 147                 goto fail;
 148         }
 149
 150         /* send Diagnostics command */
 151         *buffer = ELO_DIAG;
 152         ret = elo_smartset_send_get(dev, ELO_SEND_SMARTSET_COMMAND, buffer);
 153         if (ret < 0) {
 154                 dev_err(&dev->dev, "send Diagnostics Command failed, error %d\n",
 155                                 ret);
 156                 goto fail;
 157         }
 158
 159         /* get the result */
 160         ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE, buffer);
 161         if (ret < 0) {
 162                 dev_err(&dev->dev, "get Diagnostics Command response failed, error %d\n",
 163                                 ret);
 164                 goto fail;
 165         }
 166
 167         /* read the ack */
 168         if (*buffer != 'A') {
 169                 ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE,
 170                                 buffer);
 171                 if (ret < 0) {
 172                         dev_err(&dev->dev, "get acknowledge response failed, error %d\n",
 173                                         ret);
 174                         goto fail;
 175                 }
 176         }
 177
 178 fail:
 179         ret = elo_flush_smartset_responses(dev);
 180         if (ret < 0)
 181                 dev_err(&dev->dev, "final FLUSH_SMARTSET_RESPONSES failed, error %d\n",
 182                                 ret);
 183         queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL);
 184 }
 185
 186 /*
 187  * Not all Elo devices need the periodic HID descriptor reads.
 188  * Only firmware version M needs this.
 189  */
 190 static bool elo_broken_firmware(struct usb_device *dev)
 191 {
 192         struct usb_device *hub = dev->parent;
 193         struct usb_device *child = NULL;
 194         u16 fw_lvl = le16_to_cpu(dev->descriptor.bcdDevice);
 195         u16 child_vid, child_pid;
 196         int i;
 197
 198         if (!use_fw_quirk)
 199                 return false;
 200         if (fw_lvl != 0x10d)
 201                 return false;
 202
 203         /* iterate sibling devices of the touch controller */
 204         usb_hub_for_each_child(hub, i, child) {
 205                 child_vid = le16_to_cpu(child->descriptor.idVendor);
 206                 child_pid = le16_to_cpu(child->descriptor.idProduct);
 207
 208                 /*
 209                  * If one of the devices below is present attached as a sibling of
 210                  * the touch controller then  this is a newer IBM 4820 monitor that
 211                  * does not need the IBM-requested workaround if fw level is
 212                  * 0x010d - aka 'M'.
 213                  * No other HW can have this combination.
 214                  */
 215                 if (child_vid==0x04b3) {
 216                         switch (child_pid) {
 217                         case 0x4676: /* 4820 21x Video */
 218                         case 0x4677: /* 4820 51x Video */
 219                         case 0x4678: /* 4820 2Lx Video */
 220                         case 0x4679: /* 4820 5Lx Video */
 221                                 return false;
 222                         }
 223                 }
 224         }
 225         return true;
 226 }
 227
 228 static int elo_probe(struct hid_device *hdev, const struct hid_device_id *id)
 229 {
 230         struct elo_priv *priv;
 231         int ret;
 232
 233         if (!hid_is_usb(hdev))
 234                 return -EINVAL;
 235
 236         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 237         if (!priv)
 238                 return -ENOMEM;
 239
 240         INIT_DELAYED_WORK(&priv->work, elo_work);
 241         priv->usbdev = interface_to_usbdev(to_usb_interface(hdev->dev.parent));
 242
 243         hid_set_drvdata(hdev, priv);
 244
 245         ret = hid_parse(hdev);
 246         if (ret) {
 247                 hid_err(hdev, "parse failed\n");
 248                 goto err_free;
 249         }
 250
 251         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 252         if (ret) {
 253                 hid_err(hdev, "hw start failed\n");
 254                 goto err_free;
 255         }
 256
 257         if (elo_broken_firmware(priv->usbdev)) {
 258                 hid_info(hdev, "broken firmware found, installing workaround\n");
 259                 queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL);
 260         }
 261
 262         return 0;
 263 err_free:
 264         kfree(priv);
 265         return ret;
 266 }
 267
 268 static void elo_remove(struct hid_device *hdev)
 269 {
 270         struct elo_priv *priv = hid_get_drvdata(hdev);
 271
 272         hid_hw_stop(hdev);
 273         cancel_delayed_work_sync(&priv->work);
 274         kfree(priv);
 275 }
 276
 277 static const struct hid_device_id elo_devices[] = {
 278         { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0009), },
 279         { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0030), },
 280         { }
 281 };
 282 MODULE_DEVICE_TABLE(hid, elo_devices);
 283
 284 static struct hid_driver elo_driver = {
 285         .name = "elo",
 286         .id_table = elo_devices,
 287         .probe = elo_probe,
 288         .remove = elo_remove,
 289         .raw_event = elo_raw_event,
 290         .input_configured = elo_input_configured,
 291 };
 292
 293 static int __init elo_driver_init(void)
 294 {
 295         int ret;
 296
 297         wq = create_singlethread_workqueue("elousb");
 298         if (!wq)
 299                 return -ENOMEM;
 300
 301         ret = hid_register_driver(&elo_driver);
 302         if (ret)
 303                 destroy_workqueue(wq);
 304
 305         return ret;
 306 }
 307 module_init(elo_driver_init);
 308
 309 static void __exit elo_driver_exit(void)
 310 {
 311         hid_unregister_driver(&elo_driver);
 312         destroy_workqueue(wq);
 313 }
 314 module_exit(elo_driver_exit);
 315
 316 MODULE_AUTHOR("Jiri Slaby <jslaby@suse.cz>");
 317 MODULE_LICENSE("GPL");