2 * HID over I2C protocol implementation
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
8 * This code is partly based on "USB HID support for Linux":
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
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
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>
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>
35 #include <linux/hid.h>
36 #include <linux/mutex.h>
37 #include <linux/acpi.h>
40 #include <linux/i2c/i2c-hid.h>
43 #define I2C_HID_STARTED (1 << 0)
44 #define I2C_HID_RESET_PENDING (1 << 1)
45 #define I2C_HID_READ_PENDING (1 << 2)
47 #define I2C_HID_PWR_ON 0x00
48 #define I2C_HID_PWR_SLEEP 0x01
52 module_param(debug, bool, 0444);
53 MODULE_PARM_DESC(debug, "print a lot of debug information");
55 #define i2c_hid_dbg(ihid, fmt, arg...) \
58 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
62 __le16 wHIDDescLength;
64 __le16 wReportDescLength;
65 __le16 wReportDescRegister;
66 __le16 wInputRegister;
67 __le16 wMaxInputLength;
68 __le16 wOutputRegister;
69 __le16 wMaxOutputLength;
70 __le16 wCommandRegister;
79 unsigned int registerIndex;
94 #define I2C_HID_CMD(opcode_) \
95 .opcode = opcode_, .length = 4, \
96 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
98 /* fetch HID descriptor */
99 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
100 /* fetch report descriptors */
101 static const struct i2c_hid_cmd hid_report_descr_cmd = {
102 .registerIndex = offsetof(struct i2c_hid_desc,
103 wReportDescRegister),
107 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01),
109 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) };
110 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) };
111 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) };
112 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 };
115 * These definitions are not used here, but are defined by the spec.
116 * Keeping them here for documentation purposes.
118 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
119 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
120 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
121 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
124 static DEFINE_MUTEX(i2c_hid_open_mut);
126 /* The main device structure */
128 struct i2c_client *client; /* i2c client */
129 struct hid_device *hid; /* pointer to corresponding HID dev */
131 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
132 struct i2c_hid_desc hdesc; /* the HID Descriptor */
134 __le16 wHIDDescRegister; /* location of the i2c
135 * register of the HID
137 unsigned int bufsize; /* i2c buffer size */
138 char *inbuf; /* Input buffer */
139 char *cmdbuf; /* Command buffer */
140 char *argsbuf; /* Command arguments buffer */
142 unsigned long flags; /* device flags */
144 wait_queue_head_t wait; /* For waiting the interrupt */
146 struct i2c_hid_platform_data pdata;
149 static int __i2c_hid_command(struct i2c_client *client,
150 const struct i2c_hid_cmd *command, u8 reportID,
151 u8 reportType, u8 *args, int args_len,
152 unsigned char *buf_recv, int data_len)
154 struct i2c_hid *ihid = i2c_get_clientdata(client);
155 union command *cmd = (union command *)ihid->cmdbuf;
157 struct i2c_msg msg[2];
160 int length = command->length;
161 bool wait = command->wait;
162 unsigned int registerIndex = command->registerIndex;
164 /* special case for hid_descr_cmd */
165 if (command == &hid_descr_cmd) {
166 cmd->c.reg = ihid->wHIDDescRegister;
168 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
169 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
173 cmd->c.opcode = command->opcode;
174 cmd->c.reportTypeID = reportID | reportType << 4;
177 memcpy(cmd->data + length, args, args_len);
180 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
182 msg[0].addr = client->addr;
183 msg[0].flags = client->flags & I2C_M_TEN;
185 msg[0].buf = cmd->data;
187 msg[1].addr = client->addr;
188 msg[1].flags = client->flags & I2C_M_TEN;
189 msg[1].flags |= I2C_M_RD;
190 msg[1].len = data_len;
191 msg[1].buf = buf_recv;
193 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
197 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
199 ret = i2c_transfer(client->adapter, msg, msg_num);
202 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
205 return ret < 0 ? ret : -EIO;
210 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
211 if (!wait_event_timeout(ihid->wait,
212 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
213 msecs_to_jiffies(5000)))
215 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
221 static int i2c_hid_command(struct i2c_client *client,
222 const struct i2c_hid_cmd *command,
223 unsigned char *buf_recv, int data_len)
225 return __i2c_hid_command(client, command, 0, 0, NULL, 0,
229 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
230 u8 reportID, unsigned char *buf_recv, int data_len)
232 struct i2c_hid *ihid = i2c_get_clientdata(client);
236 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
238 i2c_hid_dbg(ihid, "%s\n", __func__);
240 if (reportID >= 0x0F) {
241 args[args_len++] = reportID;
245 args[args_len++] = readRegister & 0xFF;
246 args[args_len++] = readRegister >> 8;
248 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
249 reportType, args, args_len, buf_recv, data_len);
251 dev_err(&client->dev,
252 "failed to retrieve report from device.\n");
259 static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
260 u8 reportID, unsigned char *buf, size_t data_len)
262 struct i2c_hid *ihid = i2c_get_clientdata(client);
263 u8 *args = ihid->argsbuf;
264 const struct i2c_hid_cmd * hidcmd = &hid_set_report_cmd;
266 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
267 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
268 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
270 /* hidraw already checked that data_len < HID_MAX_BUFFER_SIZE */
271 u16 size = 2 /* size */ +
272 (reportID ? 1 : 0) /* reportID */ +
274 int args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
275 2 /* dataRegister */ +
279 i2c_hid_dbg(ihid, "%s\n", __func__);
281 if (reportID >= 0x0F) {
282 args[index++] = reportID;
287 * use the data register for feature reports or if the device does not
288 * support the output register
290 if (reportType == 0x03 || maxOutputLength == 0) {
291 args[index++] = dataRegister & 0xFF;
292 args[index++] = dataRegister >> 8;
294 args[index++] = outputRegister & 0xFF;
295 args[index++] = outputRegister >> 8;
296 hidcmd = &hid_no_cmd;
299 args[index++] = size & 0xFF;
300 args[index++] = size >> 8;
303 args[index++] = reportID;
305 memcpy(&args[index], buf, data_len);
307 ret = __i2c_hid_command(client, hidcmd, reportID,
308 reportType, args, args_len, NULL, 0);
310 dev_err(&client->dev, "failed to set a report to device.\n");
317 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
319 struct i2c_hid *ihid = i2c_get_clientdata(client);
322 i2c_hid_dbg(ihid, "%s\n", __func__);
324 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
325 0, NULL, 0, NULL, 0);
327 dev_err(&client->dev, "failed to change power setting.\n");
332 static int i2c_hid_hwreset(struct i2c_client *client)
334 struct i2c_hid *ihid = i2c_get_clientdata(client);
337 i2c_hid_dbg(ihid, "%s\n", __func__);
339 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
343 i2c_hid_dbg(ihid, "resetting...\n");
345 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
347 dev_err(&client->dev, "failed to reset device.\n");
348 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
355 static void i2c_hid_get_input(struct i2c_hid *ihid)
358 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
360 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
365 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
366 __func__, ret, size);
370 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
373 /* host or device initiated RESET completed */
374 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
375 wake_up(&ihid->wait);
379 if (ret_size > size) {
380 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
381 __func__, size, ret_size);
385 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
387 if (test_bit(I2C_HID_STARTED, &ihid->flags))
388 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
394 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
396 struct i2c_hid *ihid = dev_id;
398 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
401 i2c_hid_get_input(ihid);
406 static int i2c_hid_get_report_length(struct hid_report *report)
408 return ((report->size - 1) >> 3) + 1 +
409 report->device->report_enum[report->type].numbered + 2;
412 static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
415 struct hid_device *hid = report->device;
416 struct i2c_client *client = hid->driver_data;
417 struct i2c_hid *ihid = i2c_get_clientdata(client);
418 unsigned int size, ret_size;
420 size = i2c_hid_get_report_length(report);
421 if (i2c_hid_get_report(client,
422 report->type == HID_FEATURE_REPORT ? 0x03 : 0x01,
423 report->id, buffer, size))
426 i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, ihid->inbuf);
428 ret_size = buffer[0] | (buffer[1] << 8);
430 if (ret_size != size) {
431 dev_err(&client->dev, "error in %s size:%d / ret_size:%d\n",
432 __func__, size, ret_size);
436 /* hid->driver_lock is held as we are in probe function,
437 * we just need to setup the input fields, so using
438 * hid_report_raw_event is safe. */
439 hid_report_raw_event(hid, report->type, buffer + 2, size - 2, 1);
443 * Initialize all reports
445 static void i2c_hid_init_reports(struct hid_device *hid)
447 struct hid_report *report;
448 struct i2c_client *client = hid->driver_data;
449 struct i2c_hid *ihid = i2c_get_clientdata(client);
450 u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
453 dev_err(&client->dev, "can not retrieve initial reports\n");
457 list_for_each_entry(report,
458 &hid->report_enum[HID_FEATURE_REPORT].report_list, list)
459 i2c_hid_init_report(report, inbuf, ihid->bufsize);
465 * Traverse the supplied list of reports and find the longest
467 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
470 struct hid_report *report;
473 /* We should not rely on wMaxInputLength, as some devices may set it to
475 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
476 size = i2c_hid_get_report_length(report);
482 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
485 kfree(ihid->argsbuf);
489 ihid->argsbuf = NULL;
493 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
495 /* the worst case is computed from the set_report command with a
496 * reportID > 15 and the maximum report length */
497 int args_len = sizeof(__u8) + /* optional ReportID byte */
498 sizeof(__u16) + /* data register */
499 sizeof(__u16) + /* size of the report */
500 report_size; /* report */
502 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
503 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
504 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
506 if (!ihid->inbuf || !ihid->argsbuf || !ihid->cmdbuf) {
507 i2c_hid_free_buffers(ihid);
511 ihid->bufsize = report_size;
516 static int i2c_hid_get_raw_report(struct hid_device *hid,
517 unsigned char report_number, __u8 *buf, size_t count,
518 unsigned char report_type)
520 struct i2c_client *client = hid->driver_data;
521 struct i2c_hid *ihid = i2c_get_clientdata(client);
522 size_t ret_count, ask_count;
525 if (report_type == HID_OUTPUT_REPORT)
528 /* +2 bytes to include the size of the reply in the query buffer */
529 ask_count = min(count + 2, (size_t)ihid->bufsize);
531 ret = i2c_hid_get_report(client,
532 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
533 report_number, ihid->inbuf, ask_count);
538 ret_count = ihid->inbuf[0] | (ihid->inbuf[1] << 8);
543 ret_count = min(ret_count, ask_count);
545 /* The query buffer contains the size, dropping it in the reply */
546 count = min(count, ret_count - 2);
547 memcpy(buf, ihid->inbuf + 2, count);
552 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
553 size_t count, unsigned char report_type)
555 struct i2c_client *client = hid->driver_data;
556 int report_id = buf[0];
559 if (report_type == HID_INPUT_REPORT)
567 ret = i2c_hid_set_report(client,
568 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
569 report_id, buf, count);
571 if (report_id && ret >= 0)
572 ret++; /* add report_id to the number of transfered bytes */
577 static void i2c_hid_request(struct hid_device *hid, struct hid_report *rep,
580 struct i2c_client *client = hid->driver_data;
583 int len = i2c_hid_get_report_length(rep) - 2;
585 buf = hid_alloc_report_buf(rep, GFP_KERNEL);
590 case HID_REQ_GET_REPORT:
591 ret = i2c_hid_get_raw_report(hid, rep->id, buf, len, rep->type);
593 dev_err(&client->dev, "%s: unable to get report: %d\n",
596 hid_input_report(hid, rep->type, buf, ret, 0);
598 case HID_REQ_SET_REPORT:
599 hid_output_report(rep, buf);
600 i2c_hid_output_raw_report(hid, buf, len, rep->type);
607 static int i2c_hid_parse(struct hid_device *hid)
609 struct i2c_client *client = hid->driver_data;
610 struct i2c_hid *ihid = i2c_get_clientdata(client);
611 struct i2c_hid_desc *hdesc = &ihid->hdesc;
617 i2c_hid_dbg(ihid, "entering %s\n", __func__);
619 rsize = le16_to_cpu(hdesc->wReportDescLength);
620 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
621 dbg_hid("weird size of report descriptor (%u)\n", rsize);
626 ret = i2c_hid_hwreset(client);
629 } while (tries-- > 0 && ret);
634 rdesc = kzalloc(rsize, GFP_KERNEL);
637 dbg_hid("couldn't allocate rdesc memory\n");
641 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
643 ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize);
645 hid_err(hid, "reading report descriptor failed\n");
650 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
652 ret = hid_parse_report(hid, rdesc, rsize);
655 dbg_hid("parsing report descriptor failed\n");
662 static int i2c_hid_start(struct hid_device *hid)
664 struct i2c_client *client = hid->driver_data;
665 struct i2c_hid *ihid = i2c_get_clientdata(client);
667 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
669 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
670 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
671 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
673 if (bufsize > ihid->bufsize) {
674 i2c_hid_free_buffers(ihid);
676 ret = i2c_hid_alloc_buffers(ihid, bufsize);
682 if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
683 i2c_hid_init_reports(hid);
688 static void i2c_hid_stop(struct hid_device *hid)
690 struct i2c_client *client = hid->driver_data;
691 struct i2c_hid *ihid = i2c_get_clientdata(client);
695 i2c_hid_free_buffers(ihid);
698 static int i2c_hid_open(struct hid_device *hid)
700 struct i2c_client *client = hid->driver_data;
701 struct i2c_hid *ihid = i2c_get_clientdata(client);
704 mutex_lock(&i2c_hid_open_mut);
706 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
711 set_bit(I2C_HID_STARTED, &ihid->flags);
714 mutex_unlock(&i2c_hid_open_mut);
718 static void i2c_hid_close(struct hid_device *hid)
720 struct i2c_client *client = hid->driver_data;
721 struct i2c_hid *ihid = i2c_get_clientdata(client);
723 /* protecting hid->open to make sure we don't restart
724 * data acquistion due to a resumption we no longer
727 mutex_lock(&i2c_hid_open_mut);
729 clear_bit(I2C_HID_STARTED, &ihid->flags);
731 /* Save some power */
732 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
734 mutex_unlock(&i2c_hid_open_mut);
737 static int i2c_hid_power(struct hid_device *hid, int lvl)
739 struct i2c_client *client = hid->driver_data;
740 struct i2c_hid *ihid = i2c_get_clientdata(client);
743 i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
747 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
750 ret = i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
756 static struct hid_ll_driver i2c_hid_ll_driver = {
757 .parse = i2c_hid_parse,
758 .start = i2c_hid_start,
759 .stop = i2c_hid_stop,
760 .open = i2c_hid_open,
761 .close = i2c_hid_close,
762 .power = i2c_hid_power,
763 .request = i2c_hid_request,
766 static int i2c_hid_init_irq(struct i2c_client *client)
768 struct i2c_hid *ihid = i2c_get_clientdata(client);
771 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
773 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
774 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
777 dev_warn(&client->dev,
778 "Could not register for %s interrupt, irq = %d,"
780 client->name, client->irq, ret);
788 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
790 struct i2c_client *client = ihid->client;
791 struct i2c_hid_desc *hdesc = &ihid->hdesc;
795 /* Fetch the length of HID description, retrieve the 4 first bytes:
796 * bytes 0-1 -> length
797 * bytes 2-3 -> bcdVersion (has to be 1.00) */
798 ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer, 4);
800 i2c_hid_dbg(ihid, "%s, ihid->hdesc_buffer: %4ph\n", __func__,
804 dev_err(&client->dev,
805 "unable to fetch the size of HID descriptor (ret=%d)\n",
810 dsize = le16_to_cpu(hdesc->wHIDDescLength);
812 * the size of the HID descriptor should at least contain
813 * its size and the bcdVersion (4 bytes), and should not be greater
814 * than sizeof(struct i2c_hid_desc) as we directly fill this struct
815 * through i2c_hid_command.
817 if (dsize < 4 || dsize > sizeof(struct i2c_hid_desc)) {
818 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
823 /* check bcdVersion == 1.0 */
824 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
825 dev_err(&client->dev,
826 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
827 le16_to_cpu(hdesc->bcdVersion));
831 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
833 ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer,
836 dev_err(&client->dev, "hid_descr_cmd Fail\n");
840 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
846 static int i2c_hid_acpi_pdata(struct i2c_client *client,
847 struct i2c_hid_platform_data *pdata)
849 static u8 i2c_hid_guid[] = {
850 0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45,
851 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE,
853 union acpi_object *obj;
854 struct acpi_device *adev;
857 handle = ACPI_HANDLE(&client->dev);
858 if (!handle || acpi_bus_get_device(handle, &adev))
861 obj = acpi_evaluate_dsm_typed(handle, i2c_hid_guid, 1, 1, NULL,
864 dev_err(&client->dev, "device _DSM execution failed\n");
868 pdata->hid_descriptor_address = obj->integer.value;
874 static const struct acpi_device_id i2c_hid_acpi_match[] = {
879 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
881 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
882 struct i2c_hid_platform_data *pdata)
889 static int i2c_hid_of_probe(struct i2c_client *client,
890 struct i2c_hid_platform_data *pdata)
892 struct device *dev = &client->dev;
896 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
898 dev_err(&client->dev, "HID register address not provided\n");
902 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
906 pdata->hid_descriptor_address = val;
911 static const struct of_device_id i2c_hid_of_match[] = {
912 { .compatible = "hid-over-i2c" },
915 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
917 static inline int i2c_hid_of_probe(struct i2c_client *client,
918 struct i2c_hid_platform_data *pdata)
924 static int i2c_hid_probe(struct i2c_client *client,
925 const struct i2c_device_id *dev_id)
928 struct i2c_hid *ihid;
929 struct hid_device *hid;
931 struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
933 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
936 dev_err(&client->dev,
937 "HID over i2c has not been provided an Int IRQ\n");
941 ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
945 if (client->dev.of_node) {
946 ret = i2c_hid_of_probe(client, &ihid->pdata);
949 } else if (!platform_data) {
950 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
952 dev_err(&client->dev,
953 "HID register address not provided\n");
957 ihid->pdata = *platform_data;
960 i2c_set_clientdata(client, ihid);
962 ihid->client = client;
964 hidRegister = ihid->pdata.hid_descriptor_address;
965 ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
967 init_waitqueue_head(&ihid->wait);
969 /* we need to allocate the command buffer without knowing the maximum
970 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
971 * real computation later. */
972 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
976 ret = i2c_hid_fetch_hid_descriptor(ihid);
980 ret = i2c_hid_init_irq(client);
984 hid = hid_allocate_device();
992 hid->driver_data = client;
993 hid->ll_driver = &i2c_hid_ll_driver;
994 hid->hid_get_raw_report = i2c_hid_get_raw_report;
995 hid->hid_output_raw_report = i2c_hid_output_raw_report;
996 hid->dev.parent = &client->dev;
997 ACPI_COMPANION_SET(&hid->dev, ACPI_COMPANION(&client->dev));
999 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1000 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1001 hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1003 snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
1004 client->name, hid->vendor, hid->product);
1006 ret = hid_add_device(hid);
1009 hid_err(client, "can't add hid device: %d\n", ret);
1016 hid_destroy_device(hid);
1019 free_irq(client->irq, ihid);
1022 i2c_hid_free_buffers(ihid);
1027 static int i2c_hid_remove(struct i2c_client *client)
1029 struct i2c_hid *ihid = i2c_get_clientdata(client);
1030 struct hid_device *hid;
1033 hid_destroy_device(hid);
1035 free_irq(client->irq, ihid);
1038 i2c_hid_free_buffers(ihid);
1045 #ifdef CONFIG_PM_SLEEP
1046 static int i2c_hid_suspend(struct device *dev)
1048 struct i2c_client *client = to_i2c_client(dev);
1050 disable_irq(client->irq);
1051 if (device_may_wakeup(&client->dev))
1052 enable_irq_wake(client->irq);
1054 /* Save some power */
1055 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1060 static int i2c_hid_resume(struct device *dev)
1063 struct i2c_client *client = to_i2c_client(dev);
1065 enable_irq(client->irq);
1066 ret = i2c_hid_hwreset(client);
1070 if (device_may_wakeup(&client->dev))
1071 disable_irq_wake(client->irq);
1077 static SIMPLE_DEV_PM_OPS(i2c_hid_pm, i2c_hid_suspend, i2c_hid_resume);
1079 static const struct i2c_device_id i2c_hid_id_table[] = {
1083 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1086 static struct i2c_driver i2c_hid_driver = {
1089 .owner = THIS_MODULE,
1091 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1092 .of_match_table = of_match_ptr(i2c_hid_of_match),
1095 .probe = i2c_hid_probe,
1096 .remove = i2c_hid_remove,
1098 .id_table = i2c_hid_id_table,
1101 module_i2c_driver(i2c_hid_driver);
1103 MODULE_DESCRIPTION("HID over I2C core driver");
1104 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1105 MODULE_LICENSE("GPL");