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