Merge branch 'for-4.19/i2c-hid' into for-linus
[sfrench/cifs-2.6.git] / drivers / hid / i2c-hid / i2c-hid.c
1 /*
2  * HID over I2C protocol implementation
3  *
4  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
5  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
6  * Copyright (c) 2012 Red Hat, Inc
7  *
8  * This code is partly based on "USB HID support for Linux":
9  *
10  *  Copyright (c) 1999 Andreas Gal
11  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
12  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
13  *  Copyright (c) 2007-2008 Oliver Neukum
14  *  Copyright (c) 2006-2010 Jiri Kosina
15  *
16  * This file is subject to the terms and conditions of the GNU General Public
17  * License.  See the file COPYING in the main directory of this archive for
18  * more details.
19  */
20
21 #include <linux/module.h>
22 #include <linux/i2c.h>
23 #include <linux/interrupt.h>
24 #include <linux/input.h>
25 #include <linux/irq.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/pm.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/device.h>
31 #include <linux/wait.h>
32 #include <linux/err.h>
33 #include <linux/string.h>
34 #include <linux/list.h>
35 #include <linux/jiffies.h>
36 #include <linux/kernel.h>
37 #include <linux/hid.h>
38 #include <linux/mutex.h>
39 #include <linux/acpi.h>
40 #include <linux/of.h>
41 #include <linux/regulator/consumer.h>
42
43 #include <linux/platform_data/i2c-hid.h>
44
45 #include "../hid-ids.h"
46
47 /* quirks to control the device */
48 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV        BIT(0)
49 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET        BIT(1)
50 #define I2C_HID_QUIRK_RESEND_REPORT_DESCR       BIT(2)
51
52 /* flags */
53 #define I2C_HID_STARTED         0
54 #define I2C_HID_RESET_PENDING   1
55 #define I2C_HID_READ_PENDING    2
56
57 #define I2C_HID_PWR_ON          0x00
58 #define I2C_HID_PWR_SLEEP       0x01
59
60 /* debug option */
61 static bool debug;
62 module_param(debug, bool, 0444);
63 MODULE_PARM_DESC(debug, "print a lot of debug information");
64
65 #define i2c_hid_dbg(ihid, fmt, arg...)                                    \
66 do {                                                                      \
67         if (debug)                                                        \
68                 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
69 } while (0)
70
71 struct i2c_hid_desc {
72         __le16 wHIDDescLength;
73         __le16 bcdVersion;
74         __le16 wReportDescLength;
75         __le16 wReportDescRegister;
76         __le16 wInputRegister;
77         __le16 wMaxInputLength;
78         __le16 wOutputRegister;
79         __le16 wMaxOutputLength;
80         __le16 wCommandRegister;
81         __le16 wDataRegister;
82         __le16 wVendorID;
83         __le16 wProductID;
84         __le16 wVersionID;
85         __le32 reserved;
86 } __packed;
87
88 struct i2c_hid_cmd {
89         unsigned int registerIndex;
90         __u8 opcode;
91         unsigned int length;
92         bool wait;
93 };
94
95 union command {
96         u8 data[0];
97         struct cmd {
98                 __le16 reg;
99                 __u8 reportTypeID;
100                 __u8 opcode;
101         } __packed c;
102 };
103
104 #define I2C_HID_CMD(opcode_) \
105         .opcode = opcode_, .length = 4, \
106         .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
107
108 /* fetch HID descriptor */
109 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
110 /* fetch report descriptors */
111 static const struct i2c_hid_cmd hid_report_descr_cmd = {
112                 .registerIndex = offsetof(struct i2c_hid_desc,
113                         wReportDescRegister),
114                 .opcode = 0x00,
115                 .length = 2 };
116 /* commands */
117 static const struct i2c_hid_cmd hid_reset_cmd =         { I2C_HID_CMD(0x01),
118                                                           .wait = true };
119 static const struct i2c_hid_cmd hid_get_report_cmd =    { I2C_HID_CMD(0x02) };
120 static const struct i2c_hid_cmd hid_set_report_cmd =    { I2C_HID_CMD(0x03) };
121 static const struct i2c_hid_cmd hid_set_power_cmd =     { I2C_HID_CMD(0x08) };
122 static const struct i2c_hid_cmd hid_no_cmd =            { .length = 0 };
123
124 /*
125  * These definitions are not used here, but are defined by the spec.
126  * Keeping them here for documentation purposes.
127  *
128  * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
129  * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
130  * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
131  * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
132  */
133
134 /* The main device structure */
135 struct i2c_hid {
136         struct i2c_client       *client;        /* i2c client */
137         struct hid_device       *hid;   /* pointer to corresponding HID dev */
138         union {
139                 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
140                 struct i2c_hid_desc hdesc;      /* the HID Descriptor */
141         };
142         __le16                  wHIDDescRegister; /* location of the i2c
143                                                    * register of the HID
144                                                    * descriptor. */
145         unsigned int            bufsize;        /* i2c buffer size */
146         u8                      *inbuf;         /* Input buffer */
147         u8                      *rawbuf;        /* Raw Input buffer */
148         u8                      *cmdbuf;        /* Command buffer */
149         u8                      *argsbuf;       /* Command arguments buffer */
150
151         unsigned long           flags;          /* device flags */
152         unsigned long           quirks;         /* Various quirks */
153
154         wait_queue_head_t       wait;           /* For waiting the interrupt */
155
156         struct i2c_hid_platform_data pdata;
157
158         bool                    irq_wake_enabled;
159         struct mutex            reset_lock;
160 };
161
162 static const struct i2c_hid_quirks {
163         __u16 idVendor;
164         __u16 idProduct;
165         __u32 quirks;
166 } i2c_hid_quirks[] = {
167         { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8752,
168                 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
169         { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755,
170                 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
171         { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
172                 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
173         { I2C_VENDOR_ID_RAYD, I2C_PRODUCT_ID_RAYD_3118,
174                 I2C_HID_QUIRK_RESEND_REPORT_DESCR },
175         { USB_VENDOR_ID_SIS_TOUCH, USB_DEVICE_ID_SIS10FB_TOUCH,
176                 I2C_HID_QUIRK_RESEND_REPORT_DESCR },
177         { 0, 0 }
178 };
179
180 /*
181  * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
182  * @idVendor: the 16-bit vendor ID
183  * @idProduct: the 16-bit product ID
184  *
185  * Returns: a u32 quirks value.
186  */
187 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
188 {
189         u32 quirks = 0;
190         int n;
191
192         for (n = 0; i2c_hid_quirks[n].idVendor; n++)
193                 if (i2c_hid_quirks[n].idVendor == idVendor &&
194                     (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
195                      i2c_hid_quirks[n].idProduct == idProduct))
196                         quirks = i2c_hid_quirks[n].quirks;
197
198         return quirks;
199 }
200
201 static int __i2c_hid_command(struct i2c_client *client,
202                 const struct i2c_hid_cmd *command, u8 reportID,
203                 u8 reportType, u8 *args, int args_len,
204                 unsigned char *buf_recv, int data_len)
205 {
206         struct i2c_hid *ihid = i2c_get_clientdata(client);
207         union command *cmd = (union command *)ihid->cmdbuf;
208         int ret;
209         struct i2c_msg msg[2];
210         int msg_num = 1;
211
212         int length = command->length;
213         bool wait = command->wait;
214         unsigned int registerIndex = command->registerIndex;
215
216         /* special case for hid_descr_cmd */
217         if (command == &hid_descr_cmd) {
218                 cmd->c.reg = ihid->wHIDDescRegister;
219         } else {
220                 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
221                 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
222         }
223
224         if (length > 2) {
225                 cmd->c.opcode = command->opcode;
226                 cmd->c.reportTypeID = reportID | reportType << 4;
227         }
228
229         memcpy(cmd->data + length, args, args_len);
230         length += args_len;
231
232         i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
233
234         msg[0].addr = client->addr;
235         msg[0].flags = client->flags & I2C_M_TEN;
236         msg[0].len = length;
237         msg[0].buf = cmd->data;
238         if (data_len > 0) {
239                 msg[1].addr = client->addr;
240                 msg[1].flags = client->flags & I2C_M_TEN;
241                 msg[1].flags |= I2C_M_RD;
242                 msg[1].len = data_len;
243                 msg[1].buf = buf_recv;
244                 msg_num = 2;
245                 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
246         }
247
248         if (wait)
249                 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
250
251         ret = i2c_transfer(client->adapter, msg, msg_num);
252
253         if (data_len > 0)
254                 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
255
256         if (ret != msg_num)
257                 return ret < 0 ? ret : -EIO;
258
259         ret = 0;
260
261         if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) {
262                 msleep(100);
263         } else if (wait) {
264                 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
265                 if (!wait_event_timeout(ihid->wait,
266                                 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
267                                 msecs_to_jiffies(5000)))
268                         ret = -ENODATA;
269                 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
270         }
271
272         return ret;
273 }
274
275 static int i2c_hid_command(struct i2c_client *client,
276                 const struct i2c_hid_cmd *command,
277                 unsigned char *buf_recv, int data_len)
278 {
279         return __i2c_hid_command(client, command, 0, 0, NULL, 0,
280                                 buf_recv, data_len);
281 }
282
283 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
284                 u8 reportID, unsigned char *buf_recv, int data_len)
285 {
286         struct i2c_hid *ihid = i2c_get_clientdata(client);
287         u8 args[3];
288         int ret;
289         int args_len = 0;
290         u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
291
292         i2c_hid_dbg(ihid, "%s\n", __func__);
293
294         if (reportID >= 0x0F) {
295                 args[args_len++] = reportID;
296                 reportID = 0x0F;
297         }
298
299         args[args_len++] = readRegister & 0xFF;
300         args[args_len++] = readRegister >> 8;
301
302         ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
303                 reportType, args, args_len, buf_recv, data_len);
304         if (ret) {
305                 dev_err(&client->dev,
306                         "failed to retrieve report from device.\n");
307                 return ret;
308         }
309
310         return 0;
311 }
312
313 /**
314  * i2c_hid_set_or_send_report: forward an incoming report to the device
315  * @client: the i2c_client of the device
316  * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
317  * @reportID: the report ID
318  * @buf: the actual data to transfer, without the report ID
319  * @len: size of buf
320  * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
321  */
322 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
323                 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
324 {
325         struct i2c_hid *ihid = i2c_get_clientdata(client);
326         u8 *args = ihid->argsbuf;
327         const struct i2c_hid_cmd *hidcmd;
328         int ret;
329         u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
330         u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
331         u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
332         u16 size;
333         int args_len;
334         int index = 0;
335
336         i2c_hid_dbg(ihid, "%s\n", __func__);
337
338         if (data_len > ihid->bufsize)
339                 return -EINVAL;
340
341         size =          2                       /* size */ +
342                         (reportID ? 1 : 0)      /* reportID */ +
343                         data_len                /* buf */;
344         args_len =      (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
345                         2                       /* dataRegister */ +
346                         size                    /* args */;
347
348         if (!use_data && maxOutputLength == 0)
349                 return -ENOSYS;
350
351         if (reportID >= 0x0F) {
352                 args[index++] = reportID;
353                 reportID = 0x0F;
354         }
355
356         /*
357          * use the data register for feature reports or if the device does not
358          * support the output register
359          */
360         if (use_data) {
361                 args[index++] = dataRegister & 0xFF;
362                 args[index++] = dataRegister >> 8;
363                 hidcmd = &hid_set_report_cmd;
364         } else {
365                 args[index++] = outputRegister & 0xFF;
366                 args[index++] = outputRegister >> 8;
367                 hidcmd = &hid_no_cmd;
368         }
369
370         args[index++] = size & 0xFF;
371         args[index++] = size >> 8;
372
373         if (reportID)
374                 args[index++] = reportID;
375
376         memcpy(&args[index], buf, data_len);
377
378         ret = __i2c_hid_command(client, hidcmd, reportID,
379                 reportType, args, args_len, NULL, 0);
380         if (ret) {
381                 dev_err(&client->dev, "failed to set a report to device.\n");
382                 return ret;
383         }
384
385         return data_len;
386 }
387
388 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
389 {
390         struct i2c_hid *ihid = i2c_get_clientdata(client);
391         int ret;
392
393         i2c_hid_dbg(ihid, "%s\n", __func__);
394
395         /*
396          * Some devices require to send a command to wakeup before power on.
397          * The call will get a return value (EREMOTEIO) but device will be
398          * triggered and activated. After that, it goes like a normal device.
399          */
400         if (power_state == I2C_HID_PWR_ON &&
401             ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
402                 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
403
404                 /* Device was already activated */
405                 if (!ret)
406                         goto set_pwr_exit;
407         }
408
409         ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
410                 0, NULL, 0, NULL, 0);
411
412         if (ret)
413                 dev_err(&client->dev, "failed to change power setting.\n");
414
415 set_pwr_exit:
416         return ret;
417 }
418
419 static int i2c_hid_hwreset(struct i2c_client *client)
420 {
421         struct i2c_hid *ihid = i2c_get_clientdata(client);
422         int ret;
423
424         i2c_hid_dbg(ihid, "%s\n", __func__);
425
426         /*
427          * This prevents sending feature reports while the device is
428          * being reset. Otherwise we may lose the reset complete
429          * interrupt.
430          */
431         mutex_lock(&ihid->reset_lock);
432
433         ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
434         if (ret)
435                 goto out_unlock;
436
437         /*
438          * The HID over I2C specification states that if a DEVICE needs time
439          * after the PWR_ON request, it should utilise CLOCK stretching.
440          * However, it has been observered that the Windows driver provides a
441          * 1ms sleep between the PWR_ON and RESET requests and that some devices
442          * rely on this.
443          */
444         usleep_range(1000, 5000);
445
446         i2c_hid_dbg(ihid, "resetting...\n");
447
448         ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
449         if (ret) {
450                 dev_err(&client->dev, "failed to reset device.\n");
451                 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
452         }
453
454 out_unlock:
455         mutex_unlock(&ihid->reset_lock);
456         return ret;
457 }
458
459 static void i2c_hid_get_input(struct i2c_hid *ihid)
460 {
461         int ret;
462         u32 ret_size;
463         int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
464
465         if (size > ihid->bufsize)
466                 size = ihid->bufsize;
467
468         ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
469         if (ret != size) {
470                 if (ret < 0)
471                         return;
472
473                 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
474                         __func__, ret, size);
475                 return;
476         }
477
478         ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
479
480         if (!ret_size) {
481                 /* host or device initiated RESET completed */
482                 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
483                         wake_up(&ihid->wait);
484                 return;
485         }
486
487         if ((ret_size > size) || (ret_size < 2)) {
488                 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
489                         __func__, size, ret_size);
490                 return;
491         }
492
493         i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
494
495         if (test_bit(I2C_HID_STARTED, &ihid->flags))
496                 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
497                                 ret_size - 2, 1);
498
499         return;
500 }
501
502 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
503 {
504         struct i2c_hid *ihid = dev_id;
505
506         if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
507                 return IRQ_HANDLED;
508
509         i2c_hid_get_input(ihid);
510
511         return IRQ_HANDLED;
512 }
513
514 static int i2c_hid_get_report_length(struct hid_report *report)
515 {
516         return ((report->size - 1) >> 3) + 1 +
517                 report->device->report_enum[report->type].numbered + 2;
518 }
519
520 /*
521  * Traverse the supplied list of reports and find the longest
522  */
523 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
524                 unsigned int *max)
525 {
526         struct hid_report *report;
527         unsigned int size;
528
529         /* We should not rely on wMaxInputLength, as some devices may set it to
530          * a wrong length. */
531         list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
532                 size = i2c_hid_get_report_length(report);
533                 if (*max < size)
534                         *max = size;
535         }
536 }
537
538 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
539 {
540         kfree(ihid->inbuf);
541         kfree(ihid->rawbuf);
542         kfree(ihid->argsbuf);
543         kfree(ihid->cmdbuf);
544         ihid->inbuf = NULL;
545         ihid->rawbuf = NULL;
546         ihid->cmdbuf = NULL;
547         ihid->argsbuf = NULL;
548         ihid->bufsize = 0;
549 }
550
551 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
552 {
553         /* the worst case is computed from the set_report command with a
554          * reportID > 15 and the maximum report length */
555         int args_len = sizeof(__u8) + /* ReportID */
556                        sizeof(__u8) + /* optional ReportID byte */
557                        sizeof(__u16) + /* data register */
558                        sizeof(__u16) + /* size of the report */
559                        report_size; /* report */
560
561         ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
562         ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
563         ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
564         ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
565
566         if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
567                 i2c_hid_free_buffers(ihid);
568                 return -ENOMEM;
569         }
570
571         ihid->bufsize = report_size;
572
573         return 0;
574 }
575
576 static int i2c_hid_get_raw_report(struct hid_device *hid,
577                 unsigned char report_number, __u8 *buf, size_t count,
578                 unsigned char report_type)
579 {
580         struct i2c_client *client = hid->driver_data;
581         struct i2c_hid *ihid = i2c_get_clientdata(client);
582         size_t ret_count, ask_count;
583         int ret;
584
585         if (report_type == HID_OUTPUT_REPORT)
586                 return -EINVAL;
587
588         /* +2 bytes to include the size of the reply in the query buffer */
589         ask_count = min(count + 2, (size_t)ihid->bufsize);
590
591         ret = i2c_hid_get_report(client,
592                         report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
593                         report_number, ihid->rawbuf, ask_count);
594
595         if (ret < 0)
596                 return ret;
597
598         ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
599
600         if (ret_count <= 2)
601                 return 0;
602
603         ret_count = min(ret_count, ask_count);
604
605         /* The query buffer contains the size, dropping it in the reply */
606         count = min(count, ret_count - 2);
607         memcpy(buf, ihid->rawbuf + 2, count);
608
609         return count;
610 }
611
612 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
613                 size_t count, unsigned char report_type, bool use_data)
614 {
615         struct i2c_client *client = hid->driver_data;
616         struct i2c_hid *ihid = i2c_get_clientdata(client);
617         int report_id = buf[0];
618         int ret;
619
620         if (report_type == HID_INPUT_REPORT)
621                 return -EINVAL;
622
623         mutex_lock(&ihid->reset_lock);
624
625         if (report_id) {
626                 buf++;
627                 count--;
628         }
629
630         ret = i2c_hid_set_or_send_report(client,
631                                 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
632                                 report_id, buf, count, use_data);
633
634         if (report_id && ret >= 0)
635                 ret++; /* add report_id to the number of transfered bytes */
636
637         mutex_unlock(&ihid->reset_lock);
638
639         return ret;
640 }
641
642 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
643                 size_t count)
644 {
645         return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
646                         false);
647 }
648
649 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
650                                __u8 *buf, size_t len, unsigned char rtype,
651                                int reqtype)
652 {
653         switch (reqtype) {
654         case HID_REQ_GET_REPORT:
655                 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
656         case HID_REQ_SET_REPORT:
657                 if (buf[0] != reportnum)
658                         return -EINVAL;
659                 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
660         default:
661                 return -EIO;
662         }
663 }
664
665 static int i2c_hid_parse(struct hid_device *hid)
666 {
667         struct i2c_client *client = hid->driver_data;
668         struct i2c_hid *ihid = i2c_get_clientdata(client);
669         struct i2c_hid_desc *hdesc = &ihid->hdesc;
670         unsigned int rsize;
671         char *rdesc;
672         int ret;
673         int tries = 3;
674
675         i2c_hid_dbg(ihid, "entering %s\n", __func__);
676
677         rsize = le16_to_cpu(hdesc->wReportDescLength);
678         if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
679                 dbg_hid("weird size of report descriptor (%u)\n", rsize);
680                 return -EINVAL;
681         }
682
683         do {
684                 ret = i2c_hid_hwreset(client);
685                 if (ret)
686                         msleep(1000);
687         } while (tries-- > 0 && ret);
688
689         if (ret)
690                 return ret;
691
692         rdesc = kzalloc(rsize, GFP_KERNEL);
693
694         if (!rdesc) {
695                 dbg_hid("couldn't allocate rdesc memory\n");
696                 return -ENOMEM;
697         }
698
699         i2c_hid_dbg(ihid, "asking HID report descriptor\n");
700
701         ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize);
702         if (ret) {
703                 hid_err(hid, "reading report descriptor failed\n");
704                 kfree(rdesc);
705                 return -EIO;
706         }
707
708         i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
709
710         ret = hid_parse_report(hid, rdesc, rsize);
711         kfree(rdesc);
712         if (ret) {
713                 dbg_hid("parsing report descriptor failed\n");
714                 return ret;
715         }
716
717         return 0;
718 }
719
720 static int i2c_hid_start(struct hid_device *hid)
721 {
722         struct i2c_client *client = hid->driver_data;
723         struct i2c_hid *ihid = i2c_get_clientdata(client);
724         int ret;
725         unsigned int bufsize = HID_MIN_BUFFER_SIZE;
726
727         i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
728         i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
729         i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
730
731         if (bufsize > ihid->bufsize) {
732                 disable_irq(client->irq);
733                 i2c_hid_free_buffers(ihid);
734
735                 ret = i2c_hid_alloc_buffers(ihid, bufsize);
736                 enable_irq(client->irq);
737
738                 if (ret)
739                         return ret;
740         }
741
742         return 0;
743 }
744
745 static void i2c_hid_stop(struct hid_device *hid)
746 {
747         hid->claimed = 0;
748 }
749
750 static int i2c_hid_open(struct hid_device *hid)
751 {
752         struct i2c_client *client = hid->driver_data;
753         struct i2c_hid *ihid = i2c_get_clientdata(client);
754         int ret = 0;
755
756         ret = pm_runtime_get_sync(&client->dev);
757         if (ret < 0)
758                 return ret;
759
760         set_bit(I2C_HID_STARTED, &ihid->flags);
761         return 0;
762 }
763
764 static void i2c_hid_close(struct hid_device *hid)
765 {
766         struct i2c_client *client = hid->driver_data;
767         struct i2c_hid *ihid = i2c_get_clientdata(client);
768
769         clear_bit(I2C_HID_STARTED, &ihid->flags);
770
771         /* Save some power */
772         pm_runtime_put(&client->dev);
773 }
774
775 static int i2c_hid_power(struct hid_device *hid, int lvl)
776 {
777         struct i2c_client *client = hid->driver_data;
778         struct i2c_hid *ihid = i2c_get_clientdata(client);
779
780         i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
781
782         switch (lvl) {
783         case PM_HINT_FULLON:
784                 pm_runtime_get_sync(&client->dev);
785                 break;
786         case PM_HINT_NORMAL:
787                 pm_runtime_put(&client->dev);
788                 break;
789         }
790         return 0;
791 }
792
793 struct hid_ll_driver i2c_hid_ll_driver = {
794         .parse = i2c_hid_parse,
795         .start = i2c_hid_start,
796         .stop = i2c_hid_stop,
797         .open = i2c_hid_open,
798         .close = i2c_hid_close,
799         .power = i2c_hid_power,
800         .output_report = i2c_hid_output_report,
801         .raw_request = i2c_hid_raw_request,
802 };
803 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
804
805 static int i2c_hid_init_irq(struct i2c_client *client)
806 {
807         struct i2c_hid *ihid = i2c_get_clientdata(client);
808         unsigned long irqflags = 0;
809         int ret;
810
811         dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
812
813         if (!irq_get_trigger_type(client->irq))
814                 irqflags = IRQF_TRIGGER_LOW;
815
816         ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
817                                    irqflags | IRQF_ONESHOT, client->name, ihid);
818         if (ret < 0) {
819                 dev_warn(&client->dev,
820                         "Could not register for %s interrupt, irq = %d,"
821                         " ret = %d\n",
822                         client->name, client->irq, ret);
823
824                 return ret;
825         }
826
827         return 0;
828 }
829
830 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
831 {
832         struct i2c_client *client = ihid->client;
833         struct i2c_hid_desc *hdesc = &ihid->hdesc;
834         unsigned int dsize;
835         int ret;
836
837         /* i2c hid fetch using a fixed descriptor size (30 bytes) */
838         i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
839         ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer,
840                                 sizeof(struct i2c_hid_desc));
841         if (ret) {
842                 dev_err(&client->dev, "hid_descr_cmd failed\n");
843                 return -ENODEV;
844         }
845
846         /* Validate the length of HID descriptor, the 4 first bytes:
847          * bytes 0-1 -> length
848          * bytes 2-3 -> bcdVersion (has to be 1.00) */
849         /* check bcdVersion == 1.0 */
850         if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
851                 dev_err(&client->dev,
852                         "unexpected HID descriptor bcdVersion (0x%04hx)\n",
853                         le16_to_cpu(hdesc->bcdVersion));
854                 return -ENODEV;
855         }
856
857         /* Descriptor length should be 30 bytes as per the specification */
858         dsize = le16_to_cpu(hdesc->wHIDDescLength);
859         if (dsize != sizeof(struct i2c_hid_desc)) {
860                 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
861                         dsize);
862                 return -ENODEV;
863         }
864         i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
865         return 0;
866 }
867
868 #ifdef CONFIG_ACPI
869 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
870         /*
871          * The CHPN0001 ACPI device, which is used to describe the Chipone
872          * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.
873          */
874         {"CHPN0001", 0 },
875         { },
876 };
877
878 static int i2c_hid_acpi_pdata(struct i2c_client *client,
879                 struct i2c_hid_platform_data *pdata)
880 {
881         static guid_t i2c_hid_guid =
882                 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
883                           0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
884         union acpi_object *obj;
885         struct acpi_device *adev;
886         acpi_handle handle;
887
888         handle = ACPI_HANDLE(&client->dev);
889         if (!handle || acpi_bus_get_device(handle, &adev)) {
890                 dev_err(&client->dev, "Error could not get ACPI device\n");
891                 return -ENODEV;
892         }
893
894         if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
895                 return -ENODEV;
896
897         obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
898                                       ACPI_TYPE_INTEGER);
899         if (!obj) {
900                 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n");
901                 return -ENODEV;
902         }
903
904         pdata->hid_descriptor_address = obj->integer.value;
905         ACPI_FREE(obj);
906
907         return 0;
908 }
909
910 static void i2c_hid_acpi_fix_up_power(struct device *dev)
911 {
912         struct acpi_device *adev;
913
914         adev = ACPI_COMPANION(dev);
915         if (adev)
916                 acpi_device_fix_up_power(adev);
917 }
918
919 static const struct acpi_device_id i2c_hid_acpi_match[] = {
920         {"ACPI0C50", 0 },
921         {"PNP0C50", 0 },
922         { },
923 };
924 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
925 #else
926 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
927                 struct i2c_hid_platform_data *pdata)
928 {
929         return -ENODEV;
930 }
931
932 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
933 #endif
934
935 #ifdef CONFIG_OF
936 static int i2c_hid_of_probe(struct i2c_client *client,
937                 struct i2c_hid_platform_data *pdata)
938 {
939         struct device *dev = &client->dev;
940         u32 val;
941         int ret;
942
943         ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
944         if (ret) {
945                 dev_err(&client->dev, "HID register address not provided\n");
946                 return -ENODEV;
947         }
948         if (val >> 16) {
949                 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
950                         val);
951                 return -EINVAL;
952         }
953         pdata->hid_descriptor_address = val;
954
955         return 0;
956 }
957
958 static const struct of_device_id i2c_hid_of_match[] = {
959         { .compatible = "hid-over-i2c" },
960         {},
961 };
962 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
963 #else
964 static inline int i2c_hid_of_probe(struct i2c_client *client,
965                 struct i2c_hid_platform_data *pdata)
966 {
967         return -ENODEV;
968 }
969 #endif
970
971 static void i2c_hid_fwnode_probe(struct i2c_client *client,
972                                  struct i2c_hid_platform_data *pdata)
973 {
974         u32 val;
975
976         if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
977                                       &val))
978                 pdata->post_power_delay_ms = val;
979 }
980
981 static int i2c_hid_probe(struct i2c_client *client,
982                          const struct i2c_device_id *dev_id)
983 {
984         int ret;
985         struct i2c_hid *ihid;
986         struct hid_device *hid;
987         __u16 hidRegister;
988         struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
989
990         dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
991
992         if (!client->irq) {
993                 dev_err(&client->dev,
994                         "HID over i2c has not been provided an Int IRQ\n");
995                 return -EINVAL;
996         }
997
998         if (client->irq < 0) {
999                 if (client->irq != -EPROBE_DEFER)
1000                         dev_err(&client->dev,
1001                                 "HID over i2c doesn't have a valid IRQ\n");
1002                 return client->irq;
1003         }
1004
1005         ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1006         if (!ihid)
1007                 return -ENOMEM;
1008
1009         if (client->dev.of_node) {
1010                 ret = i2c_hid_of_probe(client, &ihid->pdata);
1011                 if (ret)
1012                         return ret;
1013         } else if (!platform_data) {
1014                 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
1015                 if (ret)
1016                         return ret;
1017         } else {
1018                 ihid->pdata = *platform_data;
1019         }
1020
1021         /* Parse platform agnostic common properties from ACPI / device tree */
1022         i2c_hid_fwnode_probe(client, &ihid->pdata);
1023
1024         ihid->pdata.supplies[0].supply = "vdd";
1025         ihid->pdata.supplies[1].supply = "vddl";
1026
1027         ret = devm_regulator_bulk_get(&client->dev,
1028                                       ARRAY_SIZE(ihid->pdata.supplies),
1029                                       ihid->pdata.supplies);
1030         if (ret)
1031                 return ret;
1032
1033         ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1034                                     ihid->pdata.supplies);
1035         if (ret < 0)
1036                 return ret;
1037
1038         if (ihid->pdata.post_power_delay_ms)
1039                 msleep(ihid->pdata.post_power_delay_ms);
1040
1041         i2c_set_clientdata(client, ihid);
1042
1043         ihid->client = client;
1044
1045         hidRegister = ihid->pdata.hid_descriptor_address;
1046         ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1047
1048         init_waitqueue_head(&ihid->wait);
1049         mutex_init(&ihid->reset_lock);
1050
1051         /* we need to allocate the command buffer without knowing the maximum
1052          * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1053          * real computation later. */
1054         ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1055         if (ret < 0)
1056                 goto err_regulator;
1057
1058         i2c_hid_acpi_fix_up_power(&client->dev);
1059
1060         pm_runtime_get_noresume(&client->dev);
1061         pm_runtime_set_active(&client->dev);
1062         pm_runtime_enable(&client->dev);
1063         device_enable_async_suspend(&client->dev);
1064
1065         /* Make sure there is something at this address */
1066         ret = i2c_smbus_read_byte(client);
1067         if (ret < 0) {
1068                 dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
1069                 ret = -ENXIO;
1070                 goto err_pm;
1071         }
1072
1073         ret = i2c_hid_fetch_hid_descriptor(ihid);
1074         if (ret < 0)
1075                 goto err_pm;
1076
1077         ret = i2c_hid_init_irq(client);
1078         if (ret < 0)
1079                 goto err_pm;
1080
1081         hid = hid_allocate_device();
1082         if (IS_ERR(hid)) {
1083                 ret = PTR_ERR(hid);
1084                 goto err_irq;
1085         }
1086
1087         ihid->hid = hid;
1088
1089         hid->driver_data = client;
1090         hid->ll_driver = &i2c_hid_ll_driver;
1091         hid->dev.parent = &client->dev;
1092         hid->bus = BUS_I2C;
1093         hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1094         hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1095         hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1096
1097         snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
1098                  client->name, hid->vendor, hid->product);
1099         strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1100
1101         ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1102
1103         ret = hid_add_device(hid);
1104         if (ret) {
1105                 if (ret != -ENODEV)
1106                         hid_err(client, "can't add hid device: %d\n", ret);
1107                 goto err_mem_free;
1108         }
1109
1110         pm_runtime_put(&client->dev);
1111         return 0;
1112
1113 err_mem_free:
1114         hid_destroy_device(hid);
1115
1116 err_irq:
1117         free_irq(client->irq, ihid);
1118
1119 err_pm:
1120         pm_runtime_put_noidle(&client->dev);
1121         pm_runtime_disable(&client->dev);
1122
1123 err_regulator:
1124         regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1125                                ihid->pdata.supplies);
1126         i2c_hid_free_buffers(ihid);
1127         return ret;
1128 }
1129
1130 static int i2c_hid_remove(struct i2c_client *client)
1131 {
1132         struct i2c_hid *ihid = i2c_get_clientdata(client);
1133         struct hid_device *hid;
1134
1135         pm_runtime_get_sync(&client->dev);
1136         pm_runtime_disable(&client->dev);
1137         pm_runtime_set_suspended(&client->dev);
1138         pm_runtime_put_noidle(&client->dev);
1139
1140         hid = ihid->hid;
1141         hid_destroy_device(hid);
1142
1143         free_irq(client->irq, ihid);
1144
1145         if (ihid->bufsize)
1146                 i2c_hid_free_buffers(ihid);
1147
1148         regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1149                                ihid->pdata.supplies);
1150
1151         return 0;
1152 }
1153
1154 static void i2c_hid_shutdown(struct i2c_client *client)
1155 {
1156         struct i2c_hid *ihid = i2c_get_clientdata(client);
1157
1158         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1159         free_irq(client->irq, ihid);
1160 }
1161
1162 #ifdef CONFIG_PM_SLEEP
1163 static int i2c_hid_suspend(struct device *dev)
1164 {
1165         struct i2c_client *client = to_i2c_client(dev);
1166         struct i2c_hid *ihid = i2c_get_clientdata(client);
1167         struct hid_device *hid = ihid->hid;
1168         int ret;
1169         int wake_status;
1170
1171         if (hid->driver && hid->driver->suspend) {
1172                 /*
1173                  * Wake up the device so that IO issues in
1174                  * HID driver's suspend code can succeed.
1175                  */
1176                 ret = pm_runtime_resume(dev);
1177                 if (ret < 0)
1178                         return ret;
1179
1180                 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1181                 if (ret < 0)
1182                         return ret;
1183         }
1184
1185         if (!pm_runtime_suspended(dev)) {
1186                 /* Save some power */
1187                 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1188
1189                 disable_irq(client->irq);
1190         }
1191
1192         if (device_may_wakeup(&client->dev)) {
1193                 wake_status = enable_irq_wake(client->irq);
1194                 if (!wake_status)
1195                         ihid->irq_wake_enabled = true;
1196                 else
1197                         hid_warn(hid, "Failed to enable irq wake: %d\n",
1198                                 wake_status);
1199         } else {
1200                 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1201                                        ihid->pdata.supplies);
1202         }
1203
1204         return 0;
1205 }
1206
1207 static int i2c_hid_resume(struct device *dev)
1208 {
1209         int ret;
1210         struct i2c_client *client = to_i2c_client(dev);
1211         struct i2c_hid *ihid = i2c_get_clientdata(client);
1212         struct hid_device *hid = ihid->hid;
1213         int wake_status;
1214
1215         if (!device_may_wakeup(&client->dev)) {
1216                 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1217                                             ihid->pdata.supplies);
1218                 if (ret)
1219                         hid_warn(hid, "Failed to enable supplies: %d\n", ret);
1220
1221                 if (ihid->pdata.post_power_delay_ms)
1222                         msleep(ihid->pdata.post_power_delay_ms);
1223         } else if (ihid->irq_wake_enabled) {
1224                 wake_status = disable_irq_wake(client->irq);
1225                 if (!wake_status)
1226                         ihid->irq_wake_enabled = false;
1227                 else
1228                         hid_warn(hid, "Failed to disable irq wake: %d\n",
1229                                 wake_status);
1230         }
1231
1232         /* We'll resume to full power */
1233         pm_runtime_disable(dev);
1234         pm_runtime_set_active(dev);
1235         pm_runtime_enable(dev);
1236
1237         enable_irq(client->irq);
1238         ret = i2c_hid_hwreset(client);
1239         if (ret)
1240                 return ret;
1241
1242         /* RAYDIUM device (2386:3118) need to re-send report descr cmd
1243          * after resume, after this it will be back normal.
1244          * otherwise it issues too many incomplete reports.
1245          */
1246         if (ihid->quirks & I2C_HID_QUIRK_RESEND_REPORT_DESCR) {
1247                 ret = i2c_hid_command(client, &hid_report_descr_cmd, NULL, 0);
1248                 if (ret)
1249                         return ret;
1250         }
1251
1252         if (hid->driver && hid->driver->reset_resume) {
1253                 ret = hid->driver->reset_resume(hid);
1254                 return ret;
1255         }
1256
1257         return 0;
1258 }
1259 #endif
1260
1261 #ifdef CONFIG_PM
1262 static int i2c_hid_runtime_suspend(struct device *dev)
1263 {
1264         struct i2c_client *client = to_i2c_client(dev);
1265
1266         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1267         disable_irq(client->irq);
1268         return 0;
1269 }
1270
1271 static int i2c_hid_runtime_resume(struct device *dev)
1272 {
1273         struct i2c_client *client = to_i2c_client(dev);
1274
1275         enable_irq(client->irq);
1276         i2c_hid_set_power(client, I2C_HID_PWR_ON);
1277         return 0;
1278 }
1279 #endif
1280
1281 static const struct dev_pm_ops i2c_hid_pm = {
1282         SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1283         SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
1284                            NULL)
1285 };
1286
1287 static const struct i2c_device_id i2c_hid_id_table[] = {
1288         { "hid", 0 },
1289         { "hid-over-i2c", 0 },
1290         { },
1291 };
1292 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1293
1294
1295 static struct i2c_driver i2c_hid_driver = {
1296         .driver = {
1297                 .name   = "i2c_hid",
1298                 .pm     = &i2c_hid_pm,
1299                 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1300                 .of_match_table = of_match_ptr(i2c_hid_of_match),
1301         },
1302
1303         .probe          = i2c_hid_probe,
1304         .remove         = i2c_hid_remove,
1305         .shutdown       = i2c_hid_shutdown,
1306         .id_table       = i2c_hid_id_table,
1307 };
1308
1309 module_i2c_driver(i2c_hid_driver);
1310
1311 MODULE_DESCRIPTION("HID over I2C core driver");
1312 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1313 MODULE_LICENSE("GPL");