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         set_bit(BTN_TOUCH, input->keybit);
  46         set_bit(ABS_PRESSURE, input->absbit);
  47         input_set_abs_params(input, ABS_PRESSURE, 0, 256, 0, 0);
  48 }
  49
  50 static void elo_process_data(struct input_dev *input, const u8 *data, int size)
  51 {
  52         int press;
  53
  54         input_report_abs(input, ABS_X, (data[3] << 8) | data[2]);
  55         input_report_abs(input, ABS_Y, (data[5] << 8) | data[4]);
  56
  57         press = 0;
  58         if (data[1] & 0x80)
  59                 press = (data[7] << 8) | data[6];
  60         input_report_abs(input, ABS_PRESSURE, press);
  61
  62         if (data[1] & 0x03) {
  63                 input_report_key(input, BTN_TOUCH, 1);
  64                 input_sync(input);
  65         }
  66
  67         if (data[1] & 0x04)
  68                 input_report_key(input, BTN_TOUCH, 0);
  69
  70         input_sync(input);
  71 }
  72
  73 static int elo_raw_event(struct hid_device *hdev, struct hid_report *report,
  74          u8 *data, int size)
  75 {
  76         struct hid_input *hidinput;
  77
  78         if (!(hdev->claimed & HID_CLAIMED_INPUT) || list_empty(&hdev->inputs))
  79                 return 0;
  80
  81         hidinput = list_first_entry(&hdev->inputs, struct hid_input, list);
  82
  83         switch (report->id) {
  84         case 0:
  85                 if (data[0] == 'T') {   /* Mandatory ELO packet marker */
  86                         elo_process_data(hidinput->input, data, size);
  87                         return 1;
  88                 }
  89                 break;
  90         default:        /* unknown report */
  91                 /* Unknown report type; pass upstream */
  92                 hid_info(hdev, "unknown report type %d\n", report->id);
  93                 break;
  94         }
  95
  96         return 0;
  97 }
  98
  99 static int elo_smartset_send_get(struct usb_device *dev, u8 command,
 100                 void *data)
 101 {
 102         unsigned int pipe;
 103         u8 dir;
 104
 105         if (command == ELO_SEND_SMARTSET_COMMAND) {
 106                 pipe = usb_sndctrlpipe(dev, 0);
 107                 dir = USB_DIR_OUT;
 108         } else if (command == ELO_GET_SMARTSET_RESPONSE) {
 109                 pipe = usb_rcvctrlpipe(dev, 0);
 110                 dir = USB_DIR_IN;
 111         } else
 112                 return -EINVAL;
 113
 114         return usb_control_msg(dev, pipe, command,
 115                         dir | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 116                         0, 0, data, ELO_SMARTSET_PACKET_SIZE,
 117                         ELO_SMARTSET_CMD_TIMEOUT);
 118 }
 119
 120 static int elo_flush_smartset_responses(struct usb_device *dev)
 121 {
 122         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 123                         ELO_FLUSH_SMARTSET_RESPONSES,
 124                         USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 125                         0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
 126 }
 127
 128 static void elo_work(struct work_struct *work)
 129 {
 130         struct elo_priv *priv = container_of(work, struct elo_priv, work.work);
 131         struct usb_device *dev = priv->usbdev;
 132         unsigned char *buffer = priv->buffer;
 133         int ret;
 134
 135         ret = elo_flush_smartset_responses(dev);
 136         if (ret < 0) {
 137                 dev_err(&dev->dev, "initial FLUSH_SMARTSET_RESPONSES failed, error %d\n",
 138                                 ret);
 139                 goto fail;
 140         }
 141
 142         /* send Diagnostics command */
 143         *buffer = ELO_DIAG;
 144         ret = elo_smartset_send_get(dev, ELO_SEND_SMARTSET_COMMAND, buffer);
 145         if (ret < 0) {
 146                 dev_err(&dev->dev, "send Diagnostics Command failed, error %d\n",
 147                                 ret);
 148                 goto fail;
 149         }
 150
 151         /* get the result */
 152         ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE, buffer);
 153         if (ret < 0) {
 154                 dev_err(&dev->dev, "get Diagnostics Command response failed, error %d\n",
 155                                 ret);
 156                 goto fail;
 157         }
 158
 159         /* read the ack */
 160         if (*buffer != 'A') {
 161                 ret = elo_smartset_send_get(dev, ELO_GET_SMARTSET_RESPONSE,
 162                                 buffer);
 163                 if (ret < 0) {
 164                         dev_err(&dev->dev, "get acknowledge response failed, error %d\n",
 165                                         ret);
 166                         goto fail;
 167                 }
 168         }
 169
 170 fail:
 171         ret = elo_flush_smartset_responses(dev);
 172         if (ret < 0)
 173                 dev_err(&dev->dev, "final FLUSH_SMARTSET_RESPONSES failed, error %d\n",
 174                                 ret);
 175         queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL);
 176 }
 177
 178 /*
 179  * Not all Elo devices need the periodic HID descriptor reads.
 180  * Only firmware version M needs this.
 181  */
 182 static bool elo_broken_firmware(struct usb_device *dev)
 183 {
 184         return use_fw_quirk && le16_to_cpu(dev->descriptor.bcdDevice) == 0x10d;
 185 }
 186
 187 static int elo_probe(struct hid_device *hdev, const struct hid_device_id *id)
 188 {
 189         struct elo_priv *priv;
 190         int ret;
 191
 192         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 193         if (!priv)
 194                 return -ENOMEM;
 195
 196         INIT_DELAYED_WORK(&priv->work, elo_work);
 197         priv->usbdev = interface_to_usbdev(to_usb_interface(hdev->dev.parent));
 198
 199         hid_set_drvdata(hdev, priv);
 200
 201         ret = hid_parse(hdev);
 202         if (ret) {
 203                 hid_err(hdev, "parse failed\n");
 204                 goto err_free;
 205         }
 206
 207         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 208         if (ret) {
 209                 hid_err(hdev, "hw start failed\n");
 210                 goto err_free;
 211         }
 212
 213         if (elo_broken_firmware(priv->usbdev)) {
 214                 hid_info(hdev, "broken firmware found, installing workaround\n");
 215                 queue_delayed_work(wq, &priv->work, ELO_PERIODIC_READ_INTERVAL);
 216         }
 217
 218         return 0;
 219 err_free:
 220         kfree(priv);
 221         return ret;
 222 }
 223
 224 static void elo_remove(struct hid_device *hdev)
 225 {
 226         struct elo_priv *priv = hid_get_drvdata(hdev);
 227
 228         hid_hw_stop(hdev);
 229         flush_workqueue(wq);
 230         kfree(priv);
 231 }
 232
 233 static const struct hid_device_id elo_devices[] = {
 234         { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0009), },
 235         { HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0030), },
 236         { }
 237 };
 238 MODULE_DEVICE_TABLE(hid, elo_devices);
 239
 240 static struct hid_driver elo_driver = {
 241         .name = "elo",
 242         .id_table = elo_devices,
 243         .probe = elo_probe,
 244         .remove = elo_remove,
 245         .raw_event = elo_raw_event,
 246         .input_configured = elo_input_configured,
 247 };
 248
 249 static int __init elo_driver_init(void)
 250 {
 251         int ret;
 252
 253         wq = create_singlethread_workqueue("elousb");
 254         if (!wq)
 255                 return -ENOMEM;
 256
 257         ret = hid_register_driver(&elo_driver);
 258         if (ret)
 259                 destroy_workqueue(wq);
 260
 261         return ret;
 262 }
 263 module_init(elo_driver_init);
 264
 265 static void __exit elo_driver_exit(void)
 266 {
 267         hid_unregister_driver(&elo_driver);
 268         destroy_workqueue(wq);
 269 }
 270 module_exit(elo_driver_exit);
 271
 272 MODULE_AUTHOR("Jiri Slaby <jslaby@suse.cz>");
 273 MODULE_LICENSE("GPL");