Commit | Line | Data |
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4a200c3b BT |
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/delay.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/pm.h> | |
28 | #include <linux/device.h> | |
29 | #include <linux/wait.h> | |
30 | #include <linux/err.h> | |
31 | #include <linux/string.h> | |
32 | #include <linux/list.h> | |
33 | #include <linux/jiffies.h> | |
34 | #include <linux/kernel.h> | |
4a200c3b | 35 | #include <linux/hid.h> |
7a7d6d9c | 36 | #include <linux/mutex.h> |
4a200c3b BT |
37 | |
38 | #include <linux/i2c/i2c-hid.h> | |
39 | ||
40 | /* flags */ | |
41 | #define I2C_HID_STARTED (1 << 0) | |
42 | #define I2C_HID_RESET_PENDING (1 << 1) | |
43 | #define I2C_HID_READ_PENDING (1 << 2) | |
44 | ||
45 | #define I2C_HID_PWR_ON 0x00 | |
46 | #define I2C_HID_PWR_SLEEP 0x01 | |
47 | ||
48 | /* debug option */ | |
ee8e8806 | 49 | static bool debug; |
4a200c3b BT |
50 | module_param(debug, bool, 0444); |
51 | MODULE_PARM_DESC(debug, "print a lot of debug information"); | |
52 | ||
fa738644 BT |
53 | #define i2c_hid_dbg(ihid, fmt, arg...) \ |
54 | do { \ | |
55 | if (debug) \ | |
56 | dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \ | |
57 | } while (0) | |
4a200c3b BT |
58 | |
59 | struct i2c_hid_desc { | |
60 | __le16 wHIDDescLength; | |
61 | __le16 bcdVersion; | |
62 | __le16 wReportDescLength; | |
63 | __le16 wReportDescRegister; | |
64 | __le16 wInputRegister; | |
65 | __le16 wMaxInputLength; | |
66 | __le16 wOutputRegister; | |
67 | __le16 wMaxOutputLength; | |
68 | __le16 wCommandRegister; | |
69 | __le16 wDataRegister; | |
70 | __le16 wVendorID; | |
71 | __le16 wProductID; | |
72 | __le16 wVersionID; | |
27174cff | 73 | __le32 reserved; |
4a200c3b BT |
74 | } __packed; |
75 | ||
76 | struct i2c_hid_cmd { | |
77 | unsigned int registerIndex; | |
78 | __u8 opcode; | |
79 | unsigned int length; | |
80 | bool wait; | |
81 | }; | |
82 | ||
83 | union command { | |
84 | u8 data[0]; | |
85 | struct cmd { | |
86 | __le16 reg; | |
87 | __u8 reportTypeID; | |
88 | __u8 opcode; | |
89 | } __packed c; | |
90 | }; | |
91 | ||
92 | #define I2C_HID_CMD(opcode_) \ | |
93 | .opcode = opcode_, .length = 4, \ | |
94 | .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister) | |
95 | ||
96 | /* fetch HID descriptor */ | |
97 | static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 }; | |
98 | /* fetch report descriptors */ | |
99 | static const struct i2c_hid_cmd hid_report_descr_cmd = { | |
100 | .registerIndex = offsetof(struct i2c_hid_desc, | |
101 | wReportDescRegister), | |
102 | .opcode = 0x00, | |
103 | .length = 2 }; | |
104 | /* commands */ | |
105 | static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01), | |
106 | .wait = true }; | |
107 | static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) }; | |
108 | static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) }; | |
4a200c3b | 109 | static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) }; |
6bf6c8bf BT |
110 | |
111 | /* | |
112 | * These definitions are not used here, but are defined by the spec. | |
113 | * Keeping them here for documentation purposes. | |
114 | * | |
115 | * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) }; | |
116 | * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) }; | |
117 | * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) }; | |
118 | * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) }; | |
119 | */ | |
4a200c3b | 120 | |
7a7d6d9c BT |
121 | static DEFINE_MUTEX(i2c_hid_open_mut); |
122 | ||
4a200c3b BT |
123 | /* The main device structure */ |
124 | struct i2c_hid { | |
125 | struct i2c_client *client; /* i2c client */ | |
126 | struct hid_device *hid; /* pointer to corresponding HID dev */ | |
127 | union { | |
128 | __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)]; | |
129 | struct i2c_hid_desc hdesc; /* the HID Descriptor */ | |
130 | }; | |
131 | __le16 wHIDDescRegister; /* location of the i2c | |
132 | * register of the HID | |
133 | * descriptor. */ | |
134 | unsigned int bufsize; /* i2c buffer size */ | |
135 | char *inbuf; /* Input buffer */ | |
136 | char *cmdbuf; /* Command buffer */ | |
137 | char *argsbuf; /* Command arguments buffer */ | |
138 | ||
139 | unsigned long flags; /* device flags */ | |
140 | ||
4a200c3b BT |
141 | wait_queue_head_t wait; /* For waiting the interrupt */ |
142 | }; | |
143 | ||
144 | static int __i2c_hid_command(struct i2c_client *client, | |
145 | const struct i2c_hid_cmd *command, u8 reportID, | |
146 | u8 reportType, u8 *args, int args_len, | |
147 | unsigned char *buf_recv, int data_len) | |
148 | { | |
149 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
150 | union command *cmd = (union command *)ihid->cmdbuf; | |
151 | int ret; | |
152 | struct i2c_msg msg[2]; | |
153 | int msg_num = 1; | |
154 | ||
155 | int length = command->length; | |
156 | bool wait = command->wait; | |
157 | unsigned int registerIndex = command->registerIndex; | |
158 | ||
159 | /* special case for hid_descr_cmd */ | |
160 | if (command == &hid_descr_cmd) { | |
161 | cmd->c.reg = ihid->wHIDDescRegister; | |
162 | } else { | |
163 | cmd->data[0] = ihid->hdesc_buffer[registerIndex]; | |
164 | cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1]; | |
165 | } | |
166 | ||
167 | if (length > 2) { | |
168 | cmd->c.opcode = command->opcode; | |
169 | cmd->c.reportTypeID = reportID | reportType << 4; | |
170 | } | |
171 | ||
172 | memcpy(cmd->data + length, args, args_len); | |
173 | length += args_len; | |
174 | ||
175 | i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data); | |
176 | ||
177 | msg[0].addr = client->addr; | |
178 | msg[0].flags = client->flags & I2C_M_TEN; | |
179 | msg[0].len = length; | |
180 | msg[0].buf = cmd->data; | |
181 | if (data_len > 0) { | |
182 | msg[1].addr = client->addr; | |
183 | msg[1].flags = client->flags & I2C_M_TEN; | |
184 | msg[1].flags |= I2C_M_RD; | |
185 | msg[1].len = data_len; | |
186 | msg[1].buf = buf_recv; | |
187 | msg_num = 2; | |
188 | set_bit(I2C_HID_READ_PENDING, &ihid->flags); | |
189 | } | |
190 | ||
191 | if (wait) | |
192 | set_bit(I2C_HID_RESET_PENDING, &ihid->flags); | |
193 | ||
194 | ret = i2c_transfer(client->adapter, msg, msg_num); | |
195 | ||
196 | if (data_len > 0) | |
197 | clear_bit(I2C_HID_READ_PENDING, &ihid->flags); | |
198 | ||
199 | if (ret != msg_num) | |
200 | return ret < 0 ? ret : -EIO; | |
201 | ||
202 | ret = 0; | |
203 | ||
204 | if (wait) { | |
205 | i2c_hid_dbg(ihid, "%s: waiting...\n", __func__); | |
206 | if (!wait_event_timeout(ihid->wait, | |
207 | !test_bit(I2C_HID_RESET_PENDING, &ihid->flags), | |
208 | msecs_to_jiffies(5000))) | |
209 | ret = -ENODATA; | |
210 | i2c_hid_dbg(ihid, "%s: finished.\n", __func__); | |
211 | } | |
212 | ||
213 | return ret; | |
214 | } | |
215 | ||
216 | static int i2c_hid_command(struct i2c_client *client, | |
217 | const struct i2c_hid_cmd *command, | |
218 | unsigned char *buf_recv, int data_len) | |
219 | { | |
220 | return __i2c_hid_command(client, command, 0, 0, NULL, 0, | |
221 | buf_recv, data_len); | |
222 | } | |
223 | ||
224 | static int i2c_hid_get_report(struct i2c_client *client, u8 reportType, | |
225 | u8 reportID, unsigned char *buf_recv, int data_len) | |
226 | { | |
227 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
228 | u8 args[3]; | |
229 | int ret; | |
230 | int args_len = 0; | |
231 | u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister); | |
232 | ||
233 | i2c_hid_dbg(ihid, "%s\n", __func__); | |
234 | ||
235 | if (reportID >= 0x0F) { | |
236 | args[args_len++] = reportID; | |
237 | reportID = 0x0F; | |
238 | } | |
239 | ||
240 | args[args_len++] = readRegister & 0xFF; | |
241 | args[args_len++] = readRegister >> 8; | |
242 | ||
243 | ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID, | |
244 | reportType, args, args_len, buf_recv, data_len); | |
245 | if (ret) { | |
246 | dev_err(&client->dev, | |
247 | "failed to retrieve report from device.\n"); | |
317b204a | 248 | return ret; |
4a200c3b BT |
249 | } |
250 | ||
251 | return 0; | |
252 | } | |
253 | ||
254 | static int i2c_hid_set_report(struct i2c_client *client, u8 reportType, | |
255 | u8 reportID, unsigned char *buf, size_t data_len) | |
256 | { | |
257 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
258 | u8 *args = ihid->argsbuf; | |
259 | int ret; | |
260 | u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister); | |
261 | ||
262 | /* hidraw already checked that data_len < HID_MAX_BUFFER_SIZE */ | |
263 | u16 size = 2 /* size */ + | |
264 | (reportID ? 1 : 0) /* reportID */ + | |
265 | data_len /* buf */; | |
266 | int args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ + | |
267 | 2 /* dataRegister */ + | |
268 | size /* args */; | |
269 | int index = 0; | |
270 | ||
271 | i2c_hid_dbg(ihid, "%s\n", __func__); | |
272 | ||
273 | if (reportID >= 0x0F) { | |
274 | args[index++] = reportID; | |
275 | reportID = 0x0F; | |
276 | } | |
277 | ||
278 | args[index++] = dataRegister & 0xFF; | |
279 | args[index++] = dataRegister >> 8; | |
280 | ||
281 | args[index++] = size & 0xFF; | |
282 | args[index++] = size >> 8; | |
283 | ||
284 | if (reportID) | |
285 | args[index++] = reportID; | |
286 | ||
287 | memcpy(&args[index], buf, data_len); | |
288 | ||
289 | ret = __i2c_hid_command(client, &hid_set_report_cmd, reportID, | |
290 | reportType, args, args_len, NULL, 0); | |
291 | if (ret) { | |
292 | dev_err(&client->dev, "failed to set a report to device.\n"); | |
317b204a | 293 | return ret; |
4a200c3b BT |
294 | } |
295 | ||
296 | return data_len; | |
297 | } | |
298 | ||
299 | static int i2c_hid_set_power(struct i2c_client *client, int power_state) | |
300 | { | |
301 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
302 | int ret; | |
303 | ||
304 | i2c_hid_dbg(ihid, "%s\n", __func__); | |
305 | ||
306 | ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state, | |
307 | 0, NULL, 0, NULL, 0); | |
308 | if (ret) | |
309 | dev_err(&client->dev, "failed to change power setting.\n"); | |
310 | ||
311 | return ret; | |
312 | } | |
313 | ||
314 | static int i2c_hid_hwreset(struct i2c_client *client) | |
315 | { | |
316 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
317 | int ret; | |
318 | ||
319 | i2c_hid_dbg(ihid, "%s\n", __func__); | |
320 | ||
321 | ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); | |
322 | if (ret) | |
323 | return ret; | |
324 | ||
325 | i2c_hid_dbg(ihid, "resetting...\n"); | |
326 | ||
327 | ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0); | |
328 | if (ret) { | |
329 | dev_err(&client->dev, "failed to reset device.\n"); | |
330 | i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); | |
331 | return ret; | |
332 | } | |
333 | ||
334 | return 0; | |
335 | } | |
336 | ||
317b204a | 337 | static void i2c_hid_get_input(struct i2c_hid *ihid) |
4a200c3b BT |
338 | { |
339 | int ret, ret_size; | |
340 | int size = le16_to_cpu(ihid->hdesc.wMaxInputLength); | |
341 | ||
342 | ret = i2c_master_recv(ihid->client, ihid->inbuf, size); | |
343 | if (ret != size) { | |
344 | if (ret < 0) | |
317b204a | 345 | return; |
4a200c3b BT |
346 | |
347 | dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n", | |
348 | __func__, ret, size); | |
317b204a | 349 | return; |
4a200c3b BT |
350 | } |
351 | ||
352 | ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8; | |
353 | ||
354 | if (!ret_size) { | |
355 | /* host or device initiated RESET completed */ | |
356 | if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags)) | |
357 | wake_up(&ihid->wait); | |
317b204a | 358 | return; |
4a200c3b BT |
359 | } |
360 | ||
361 | if (ret_size > size) { | |
362 | dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n", | |
363 | __func__, size, ret_size); | |
317b204a | 364 | return; |
4a200c3b BT |
365 | } |
366 | ||
367 | i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf); | |
368 | ||
369 | if (test_bit(I2C_HID_STARTED, &ihid->flags)) | |
370 | hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2, | |
371 | ret_size - 2, 1); | |
372 | ||
317b204a | 373 | return; |
4a200c3b BT |
374 | } |
375 | ||
376 | static irqreturn_t i2c_hid_irq(int irq, void *dev_id) | |
377 | { | |
378 | struct i2c_hid *ihid = dev_id; | |
379 | ||
380 | if (test_bit(I2C_HID_READ_PENDING, &ihid->flags)) | |
381 | return IRQ_HANDLED; | |
382 | ||
383 | i2c_hid_get_input(ihid); | |
384 | ||
385 | return IRQ_HANDLED; | |
386 | } | |
387 | ||
388 | static int i2c_hid_get_report_length(struct hid_report *report) | |
389 | { | |
390 | return ((report->size - 1) >> 3) + 1 + | |
391 | report->device->report_enum[report->type].numbered + 2; | |
392 | } | |
393 | ||
394 | static void i2c_hid_init_report(struct hid_report *report, u8 *buffer, | |
395 | size_t bufsize) | |
396 | { | |
397 | struct hid_device *hid = report->device; | |
398 | struct i2c_client *client = hid->driver_data; | |
399 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
400 | unsigned int size, ret_size; | |
401 | ||
402 | size = i2c_hid_get_report_length(report); | |
c737bcf9 | 403 | if (i2c_hid_get_report(client, |
4a200c3b | 404 | report->type == HID_FEATURE_REPORT ? 0x03 : 0x01, |
c737bcf9 BT |
405 | report->id, buffer, size)) |
406 | return; | |
4a200c3b BT |
407 | |
408 | i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, ihid->inbuf); | |
409 | ||
410 | ret_size = buffer[0] | (buffer[1] << 8); | |
411 | ||
412 | if (ret_size != size) { | |
413 | dev_err(&client->dev, "error in %s size:%d / ret_size:%d\n", | |
414 | __func__, size, ret_size); | |
415 | return; | |
416 | } | |
417 | ||
418 | /* hid->driver_lock is held as we are in probe function, | |
419 | * we just need to setup the input fields, so using | |
420 | * hid_report_raw_event is safe. */ | |
421 | hid_report_raw_event(hid, report->type, buffer + 2, size - 2, 1); | |
422 | } | |
423 | ||
424 | /* | |
425 | * Initialize all reports | |
426 | */ | |
427 | static void i2c_hid_init_reports(struct hid_device *hid) | |
428 | { | |
429 | struct hid_report *report; | |
430 | struct i2c_client *client = hid->driver_data; | |
431 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
432 | u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL); | |
433 | ||
317b204a BT |
434 | if (!inbuf) { |
435 | dev_err(&client->dev, "can not retrieve initial reports\n"); | |
4a200c3b | 436 | return; |
317b204a | 437 | } |
4a200c3b BT |
438 | |
439 | list_for_each_entry(report, | |
440 | &hid->report_enum[HID_INPUT_REPORT].report_list, list) | |
441 | i2c_hid_init_report(report, inbuf, ihid->bufsize); | |
442 | ||
443 | list_for_each_entry(report, | |
444 | &hid->report_enum[HID_FEATURE_REPORT].report_list, list) | |
445 | i2c_hid_init_report(report, inbuf, ihid->bufsize); | |
446 | ||
447 | kfree(inbuf); | |
448 | } | |
449 | ||
450 | /* | |
451 | * Traverse the supplied list of reports and find the longest | |
452 | */ | |
453 | static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type, | |
454 | unsigned int *max) | |
455 | { | |
456 | struct hid_report *report; | |
457 | unsigned int size; | |
458 | ||
459 | /* We should not rely on wMaxInputLength, as some devices may set it to | |
460 | * a wrong length. */ | |
461 | list_for_each_entry(report, &hid->report_enum[type].report_list, list) { | |
462 | size = i2c_hid_get_report_length(report); | |
463 | if (*max < size) | |
464 | *max = size; | |
465 | } | |
466 | } | |
467 | ||
29b45787 BT |
468 | static void i2c_hid_free_buffers(struct i2c_hid *ihid) |
469 | { | |
470 | kfree(ihid->inbuf); | |
471 | kfree(ihid->argsbuf); | |
472 | kfree(ihid->cmdbuf); | |
473 | ihid->inbuf = NULL; | |
474 | ihid->cmdbuf = NULL; | |
475 | ihid->argsbuf = NULL; | |
476 | ihid->bufsize = 0; | |
477 | } | |
478 | ||
479 | static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) | |
4a200c3b BT |
480 | { |
481 | /* the worst case is computed from the set_report command with a | |
482 | * reportID > 15 and the maximum report length */ | |
483 | int args_len = sizeof(__u8) + /* optional ReportID byte */ | |
484 | sizeof(__u16) + /* data register */ | |
485 | sizeof(__u16) + /* size of the report */ | |
29b45787 | 486 | report_size; /* report */ |
4a200c3b | 487 | |
29b45787 | 488 | ihid->inbuf = kzalloc(report_size, GFP_KERNEL); |
4a200c3b | 489 | ihid->argsbuf = kzalloc(args_len, GFP_KERNEL); |
4a200c3b BT |
490 | ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL); |
491 | ||
29b45787 BT |
492 | if (!ihid->inbuf || !ihid->argsbuf || !ihid->cmdbuf) { |
493 | i2c_hid_free_buffers(ihid); | |
4a200c3b BT |
494 | return -ENOMEM; |
495 | } | |
496 | ||
29b45787 | 497 | ihid->bufsize = report_size; |
4a200c3b | 498 | |
29b45787 | 499 | return 0; |
4a200c3b BT |
500 | } |
501 | ||
502 | static int i2c_hid_get_raw_report(struct hid_device *hid, | |
503 | unsigned char report_number, __u8 *buf, size_t count, | |
504 | unsigned char report_type) | |
505 | { | |
506 | struct i2c_client *client = hid->driver_data; | |
507 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
e5b50fe7 | 508 | size_t ret_count, ask_count; |
4a200c3b BT |
509 | int ret; |
510 | ||
511 | if (report_type == HID_OUTPUT_REPORT) | |
512 | return -EINVAL; | |
513 | ||
e5b50fe7 BT |
514 | /* +2 bytes to include the size of the reply in the query buffer */ |
515 | ask_count = min(count + 2, (size_t)ihid->bufsize); | |
4a200c3b BT |
516 | |
517 | ret = i2c_hid_get_report(client, | |
518 | report_type == HID_FEATURE_REPORT ? 0x03 : 0x01, | |
e5b50fe7 | 519 | report_number, ihid->inbuf, ask_count); |
4a200c3b BT |
520 | |
521 | if (ret < 0) | |
522 | return ret; | |
523 | ||
e5b50fe7 | 524 | ret_count = ihid->inbuf[0] | (ihid->inbuf[1] << 8); |
4a200c3b | 525 | |
9afd09a1 | 526 | if (ret_count <= 2) |
e5b50fe7 BT |
527 | return 0; |
528 | ||
529 | ret_count = min(ret_count, ask_count); | |
530 | ||
531 | /* The query buffer contains the size, dropping it in the reply */ | |
532 | count = min(count, ret_count - 2); | |
4a200c3b BT |
533 | memcpy(buf, ihid->inbuf + 2, count); |
534 | ||
535 | return count; | |
536 | } | |
537 | ||
538 | static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf, | |
539 | size_t count, unsigned char report_type) | |
540 | { | |
541 | struct i2c_client *client = hid->driver_data; | |
542 | int report_id = buf[0]; | |
543 | ||
544 | if (report_type == HID_INPUT_REPORT) | |
545 | return -EINVAL; | |
546 | ||
547 | return i2c_hid_set_report(client, | |
548 | report_type == HID_FEATURE_REPORT ? 0x03 : 0x02, | |
549 | report_id, buf, count); | |
550 | } | |
551 | ||
552 | static int i2c_hid_parse(struct hid_device *hid) | |
553 | { | |
554 | struct i2c_client *client = hid->driver_data; | |
555 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
556 | struct i2c_hid_desc *hdesc = &ihid->hdesc; | |
557 | unsigned int rsize; | |
558 | char *rdesc; | |
559 | int ret; | |
560 | int tries = 3; | |
561 | ||
562 | i2c_hid_dbg(ihid, "entering %s\n", __func__); | |
563 | ||
564 | rsize = le16_to_cpu(hdesc->wReportDescLength); | |
565 | if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) { | |
566 | dbg_hid("weird size of report descriptor (%u)\n", rsize); | |
567 | return -EINVAL; | |
568 | } | |
569 | ||
570 | do { | |
571 | ret = i2c_hid_hwreset(client); | |
572 | if (ret) | |
573 | msleep(1000); | |
574 | } while (tries-- > 0 && ret); | |
575 | ||
576 | if (ret) | |
577 | return ret; | |
578 | ||
579 | rdesc = kzalloc(rsize, GFP_KERNEL); | |
580 | ||
581 | if (!rdesc) { | |
582 | dbg_hid("couldn't allocate rdesc memory\n"); | |
583 | return -ENOMEM; | |
584 | } | |
585 | ||
586 | i2c_hid_dbg(ihid, "asking HID report descriptor\n"); | |
587 | ||
588 | ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize); | |
589 | if (ret) { | |
590 | hid_err(hid, "reading report descriptor failed\n"); | |
591 | kfree(rdesc); | |
592 | return -EIO; | |
593 | } | |
594 | ||
595 | i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc); | |
596 | ||
597 | ret = hid_parse_report(hid, rdesc, rsize); | |
598 | kfree(rdesc); | |
599 | if (ret) { | |
600 | dbg_hid("parsing report descriptor failed\n"); | |
601 | return ret; | |
602 | } | |
603 | ||
604 | return 0; | |
605 | } | |
606 | ||
607 | static int i2c_hid_start(struct hid_device *hid) | |
608 | { | |
609 | struct i2c_client *client = hid->driver_data; | |
610 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
611 | int ret; | |
29b45787 | 612 | unsigned int bufsize = HID_MIN_BUFFER_SIZE; |
4a200c3b | 613 | |
29b45787 BT |
614 | i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize); |
615 | i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize); | |
616 | i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize); | |
4a200c3b | 617 | |
29b45787 | 618 | if (bufsize > ihid->bufsize) { |
4a200c3b BT |
619 | i2c_hid_free_buffers(ihid); |
620 | ||
29b45787 | 621 | ret = i2c_hid_alloc_buffers(ihid, bufsize); |
4a200c3b | 622 | |
29b45787 | 623 | if (ret) |
4a200c3b | 624 | return ret; |
4a200c3b BT |
625 | } |
626 | ||
627 | if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS)) | |
628 | i2c_hid_init_reports(hid); | |
629 | ||
630 | return 0; | |
631 | } | |
632 | ||
633 | static void i2c_hid_stop(struct hid_device *hid) | |
634 | { | |
635 | struct i2c_client *client = hid->driver_data; | |
636 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
637 | ||
638 | hid->claimed = 0; | |
639 | ||
640 | i2c_hid_free_buffers(ihid); | |
641 | } | |
642 | ||
643 | static int i2c_hid_open(struct hid_device *hid) | |
644 | { | |
645 | struct i2c_client *client = hid->driver_data; | |
646 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
7a7d6d9c | 647 | int ret = 0; |
4a200c3b | 648 | |
7a7d6d9c | 649 | mutex_lock(&i2c_hid_open_mut); |
4a200c3b BT |
650 | if (!hid->open++) { |
651 | ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); | |
652 | if (ret) { | |
653 | hid->open--; | |
7a7d6d9c | 654 | goto done; |
4a200c3b BT |
655 | } |
656 | set_bit(I2C_HID_STARTED, &ihid->flags); | |
657 | } | |
7a7d6d9c BT |
658 | done: |
659 | mutex_unlock(&i2c_hid_open_mut); | |
660 | return ret; | |
4a200c3b BT |
661 | } |
662 | ||
663 | static void i2c_hid_close(struct hid_device *hid) | |
664 | { | |
665 | struct i2c_client *client = hid->driver_data; | |
666 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
667 | ||
668 | /* protecting hid->open to make sure we don't restart | |
669 | * data acquistion due to a resumption we no longer | |
670 | * care about | |
671 | */ | |
7a7d6d9c | 672 | mutex_lock(&i2c_hid_open_mut); |
4a200c3b BT |
673 | if (!--hid->open) { |
674 | clear_bit(I2C_HID_STARTED, &ihid->flags); | |
675 | ||
676 | /* Save some power */ | |
677 | i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); | |
678 | } | |
7a7d6d9c | 679 | mutex_unlock(&i2c_hid_open_mut); |
4a200c3b BT |
680 | } |
681 | ||
682 | static int i2c_hid_power(struct hid_device *hid, int lvl) | |
683 | { | |
684 | struct i2c_client *client = hid->driver_data; | |
685 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
686 | int ret = 0; | |
687 | ||
688 | i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl); | |
689 | ||
690 | switch (lvl) { | |
691 | case PM_HINT_FULLON: | |
692 | ret = i2c_hid_set_power(client, I2C_HID_PWR_ON); | |
693 | break; | |
694 | case PM_HINT_NORMAL: | |
695 | ret = i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); | |
696 | break; | |
697 | } | |
698 | return ret; | |
699 | } | |
700 | ||
701 | static int i2c_hid_hidinput_input_event(struct input_dev *dev, | |
702 | unsigned int type, unsigned int code, int value) | |
703 | { | |
704 | struct hid_device *hid = input_get_drvdata(dev); | |
705 | struct hid_field *field; | |
706 | int offset; | |
707 | ||
708 | if (type == EV_FF) | |
709 | return input_ff_event(dev, type, code, value); | |
710 | ||
711 | if (type != EV_LED) | |
712 | return -1; | |
713 | ||
714 | offset = hidinput_find_field(hid, type, code, &field); | |
715 | ||
716 | if (offset == -1) { | |
717 | hid_warn(dev, "event field not found\n"); | |
718 | return -1; | |
719 | } | |
720 | ||
317b204a | 721 | return hid_set_field(field, offset, value); |
4a200c3b BT |
722 | } |
723 | ||
724 | static struct hid_ll_driver i2c_hid_ll_driver = { | |
725 | .parse = i2c_hid_parse, | |
726 | .start = i2c_hid_start, | |
727 | .stop = i2c_hid_stop, | |
728 | .open = i2c_hid_open, | |
729 | .close = i2c_hid_close, | |
730 | .power = i2c_hid_power, | |
731 | .hidinput_input_event = i2c_hid_hidinput_input_event, | |
732 | }; | |
733 | ||
0fe763c5 | 734 | static int i2c_hid_init_irq(struct i2c_client *client) |
4a200c3b BT |
735 | { |
736 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
737 | int ret; | |
738 | ||
739 | dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq); | |
740 | ||
741 | ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq, | |
742 | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, | |
743 | client->name, ihid); | |
744 | if (ret < 0) { | |
9972dcc2 | 745 | dev_warn(&client->dev, |
4a200c3b BT |
746 | "Could not register for %s interrupt, irq = %d," |
747 | " ret = %d\n", | |
9972dcc2 | 748 | client->name, client->irq, ret); |
4a200c3b BT |
749 | |
750 | return ret; | |
751 | } | |
752 | ||
4a200c3b BT |
753 | return 0; |
754 | } | |
755 | ||
0fe763c5 | 756 | static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid) |
4a200c3b BT |
757 | { |
758 | struct i2c_client *client = ihid->client; | |
759 | struct i2c_hid_desc *hdesc = &ihid->hdesc; | |
760 | unsigned int dsize; | |
761 | int ret; | |
762 | ||
763 | /* Fetch the length of HID description, retrieve the 4 first bytes: | |
764 | * bytes 0-1 -> length | |
765 | * bytes 2-3 -> bcdVersion (has to be 1.00) */ | |
766 | ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer, 4); | |
767 | ||
768 | i2c_hid_dbg(ihid, "%s, ihid->hdesc_buffer: %*ph\n", | |
769 | __func__, 4, ihid->hdesc_buffer); | |
770 | ||
771 | if (ret) { | |
9972dcc2 BT |
772 | dev_err(&client->dev, |
773 | "unable to fetch the size of HID descriptor (ret=%d)\n", | |
4a200c3b BT |
774 | ret); |
775 | return -ENODEV; | |
776 | } | |
777 | ||
778 | dsize = le16_to_cpu(hdesc->wHIDDescLength); | |
27174cff BT |
779 | /* |
780 | * the size of the HID descriptor should at least contain | |
781 | * its size and the bcdVersion (4 bytes), and should not be greater | |
782 | * than sizeof(struct i2c_hid_desc) as we directly fill this struct | |
783 | * through i2c_hid_command. | |
784 | */ | |
785 | if (dsize < 4 || dsize > sizeof(struct i2c_hid_desc)) { | |
4a200c3b BT |
786 | dev_err(&client->dev, "weird size of HID descriptor (%u)\n", |
787 | dsize); | |
788 | return -ENODEV; | |
789 | } | |
790 | ||
791 | /* check bcdVersion == 1.0 */ | |
792 | if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) { | |
793 | dev_err(&client->dev, | |
9972dcc2 | 794 | "unexpected HID descriptor bcdVersion (0x%04hx)\n", |
4a200c3b BT |
795 | le16_to_cpu(hdesc->bcdVersion)); |
796 | return -ENODEV; | |
797 | } | |
798 | ||
799 | i2c_hid_dbg(ihid, "Fetching the HID descriptor\n"); | |
800 | ||
801 | ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer, | |
802 | dsize); | |
803 | if (ret) { | |
804 | dev_err(&client->dev, "hid_descr_cmd Fail\n"); | |
805 | return -ENODEV; | |
806 | } | |
807 | ||
808 | i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer); | |
809 | ||
810 | return 0; | |
811 | } | |
812 | ||
0fe763c5 GKH |
813 | static int i2c_hid_probe(struct i2c_client *client, |
814 | const struct i2c_device_id *dev_id) | |
4a200c3b BT |
815 | { |
816 | int ret; | |
817 | struct i2c_hid *ihid; | |
818 | struct hid_device *hid; | |
819 | __u16 hidRegister; | |
820 | struct i2c_hid_platform_data *platform_data = client->dev.platform_data; | |
821 | ||
822 | dbg_hid("HID probe called for i2c 0x%02x\n", client->addr); | |
823 | ||
824 | if (!platform_data) { | |
825 | dev_err(&client->dev, "HID register address not provided\n"); | |
826 | return -EINVAL; | |
827 | } | |
828 | ||
829 | if (!client->irq) { | |
830 | dev_err(&client->dev, | |
831 | "HID over i2c has not been provided an Int IRQ\n"); | |
832 | return -EINVAL; | |
833 | } | |
834 | ||
835 | ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL); | |
836 | if (!ihid) | |
837 | return -ENOMEM; | |
838 | ||
839 | i2c_set_clientdata(client, ihid); | |
840 | ||
841 | ihid->client = client; | |
842 | ||
843 | hidRegister = platform_data->hid_descriptor_address; | |
844 | ihid->wHIDDescRegister = cpu_to_le16(hidRegister); | |
845 | ||
846 | init_waitqueue_head(&ihid->wait); | |
847 | ||
848 | /* we need to allocate the command buffer without knowing the maximum | |
849 | * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the | |
850 | * real computation later. */ | |
29b45787 BT |
851 | ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE); |
852 | if (ret < 0) | |
853 | goto err; | |
4a200c3b BT |
854 | |
855 | ret = i2c_hid_fetch_hid_descriptor(ihid); | |
856 | if (ret < 0) | |
857 | goto err; | |
858 | ||
859 | ret = i2c_hid_init_irq(client); | |
860 | if (ret < 0) | |
861 | goto err; | |
862 | ||
863 | hid = hid_allocate_device(); | |
864 | if (IS_ERR(hid)) { | |
865 | ret = PTR_ERR(hid); | |
8a1bbb53 | 866 | goto err_irq; |
4a200c3b BT |
867 | } |
868 | ||
869 | ihid->hid = hid; | |
870 | ||
871 | hid->driver_data = client; | |
872 | hid->ll_driver = &i2c_hid_ll_driver; | |
873 | hid->hid_get_raw_report = i2c_hid_get_raw_report; | |
874 | hid->hid_output_raw_report = i2c_hid_output_raw_report; | |
875 | hid->dev.parent = &client->dev; | |
876 | hid->bus = BUS_I2C; | |
877 | hid->version = le16_to_cpu(ihid->hdesc.bcdVersion); | |
878 | hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID); | |
879 | hid->product = le16_to_cpu(ihid->hdesc.wProductID); | |
880 | ||
9972dcc2 | 881 | snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX", |
4a200c3b BT |
882 | client->name, hid->vendor, hid->product); |
883 | ||
884 | ret = hid_add_device(hid); | |
885 | if (ret) { | |
886 | if (ret != -ENODEV) | |
887 | hid_err(client, "can't add hid device: %d\n", ret); | |
888 | goto err_mem_free; | |
889 | } | |
890 | ||
891 | return 0; | |
892 | ||
893 | err_mem_free: | |
894 | hid_destroy_device(hid); | |
895 | ||
8a1bbb53 BT |
896 | err_irq: |
897 | free_irq(client->irq, ihid); | |
4a200c3b | 898 | |
8a1bbb53 | 899 | err: |
3c626024 | 900 | i2c_hid_free_buffers(ihid); |
4a200c3b BT |
901 | kfree(ihid); |
902 | return ret; | |
903 | } | |
904 | ||
0fe763c5 | 905 | static int i2c_hid_remove(struct i2c_client *client) |
4a200c3b BT |
906 | { |
907 | struct i2c_hid *ihid = i2c_get_clientdata(client); | |
908 | struct hid_device *hid; | |
909 | ||
4a200c3b BT |
910 | hid = ihid->hid; |
911 | hid_destroy_device(hid); | |
912 | ||
913 | free_irq(client->irq, ihid); | |
914 | ||
134ebfd8 BT |
915 | if (ihid->bufsize) |
916 | i2c_hid_free_buffers(ihid); | |
917 | ||
4a200c3b BT |
918 | kfree(ihid); |
919 | ||
920 | return 0; | |
921 | } | |
922 | ||
923 | #ifdef CONFIG_PM_SLEEP | |
924 | static int i2c_hid_suspend(struct device *dev) | |
925 | { | |
926 | struct i2c_client *client = to_i2c_client(dev); | |
4a200c3b BT |
927 | |
928 | if (device_may_wakeup(&client->dev)) | |
8a1bbb53 | 929 | enable_irq_wake(client->irq); |
4a200c3b BT |
930 | |
931 | /* Save some power */ | |
932 | i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); | |
933 | ||
934 | return 0; | |
935 | } | |
936 | ||
937 | static int i2c_hid_resume(struct device *dev) | |
938 | { | |
939 | int ret; | |
940 | struct i2c_client *client = to_i2c_client(dev); | |
941 | ||
942 | ret = i2c_hid_hwreset(client); | |
943 | if (ret) | |
944 | return ret; | |
945 | ||
946 | if (device_may_wakeup(&client->dev)) | |
947 | disable_irq_wake(client->irq); | |
948 | ||
949 | return 0; | |
950 | } | |
951 | #endif | |
952 | ||
953 | static SIMPLE_DEV_PM_OPS(i2c_hid_pm, i2c_hid_suspend, i2c_hid_resume); | |
954 | ||
955 | static const struct i2c_device_id i2c_hid_id_table[] = { | |
24ebb37e | 956 | { "hid", 0 }, |
4a200c3b BT |
957 | { }, |
958 | }; | |
959 | MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table); | |
960 | ||
961 | ||
962 | static struct i2c_driver i2c_hid_driver = { | |
963 | .driver = { | |
964 | .name = "i2c_hid", | |
965 | .owner = THIS_MODULE, | |
966 | .pm = &i2c_hid_pm, | |
967 | }, | |
968 | ||
969 | .probe = i2c_hid_probe, | |
0fe763c5 | 970 | .remove = i2c_hid_remove, |
4a200c3b BT |
971 | |
972 | .id_table = i2c_hid_id_table, | |
973 | }; | |
974 | ||
975 | module_i2c_driver(i2c_hid_driver); | |
976 | ||
977 | MODULE_DESCRIPTION("HID over I2C core driver"); | |
978 | MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); | |
979 | MODULE_LICENSE("GPL"); |