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/pm_runtime.h>
29 #include <linux/device.h>
30 #include <linux/wait.h>
31 #include <linux/err.h>
32 #include <linux/string.h>
33 #include <linux/list.h>
34 #include <linux/jiffies.h>
35 #include <linux/kernel.h>
36 #include <linux/hid.h>
37 #include <linux/mutex.h>
38 #include <linux/acpi.h>
41 #include <linux/i2c/i2c-hid.h>
44 #define I2C_HID_STARTED (1 << 0)
45 #define I2C_HID_RESET_PENDING (1 << 1)
46 #define I2C_HID_READ_PENDING (1 << 2)
48 #define I2C_HID_PWR_ON 0x00
49 #define I2C_HID_PWR_SLEEP 0x01
53 module_param(debug, bool, 0444);
54 MODULE_PARM_DESC(debug, "print a lot of debug information");
56 #define i2c_hid_dbg(ihid, fmt, arg...) \
59 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
63 __le16 wHIDDescLength;
65 __le16 wReportDescLength;
66 __le16 wReportDescRegister;
67 __le16 wInputRegister;
68 __le16 wMaxInputLength;
69 __le16 wOutputRegister;
70 __le16 wMaxOutputLength;
71 __le16 wCommandRegister;
80 unsigned int registerIndex;
95 #define I2C_HID_CMD(opcode_) \
96 .opcode = opcode_, .length = 4, \
97 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
99 /* fetch HID descriptor */
100 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
101 /* fetch report descriptors */
102 static const struct i2c_hid_cmd hid_report_descr_cmd = {
103 .registerIndex = offsetof(struct i2c_hid_desc,
104 wReportDescRegister),
108 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01),
110 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) };
111 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) };
112 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) };
113 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 };
116 * These definitions are not used here, but are defined by the spec.
117 * Keeping them here for documentation purposes.
119 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
120 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
121 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
122 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
125 static DEFINE_MUTEX(i2c_hid_open_mut);
127 /* The main device structure */
129 struct i2c_client *client; /* i2c client */
130 struct hid_device *hid; /* pointer to corresponding HID dev */
132 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
133 struct i2c_hid_desc hdesc; /* the HID Descriptor */
135 __le16 wHIDDescRegister; /* location of the i2c
136 * register of the HID
138 unsigned int bufsize; /* i2c buffer size */
139 char *inbuf; /* Input buffer */
140 char *rawbuf; /* Raw Input buffer */
141 char *cmdbuf; /* Command buffer */
142 char *argsbuf; /* Command arguments buffer */
144 unsigned long flags; /* device flags */
146 wait_queue_head_t wait; /* For waiting the interrupt */
148 struct i2c_hid_platform_data pdata;
151 static int __i2c_hid_command(struct i2c_client *client,
152 const struct i2c_hid_cmd *command, u8 reportID,
153 u8 reportType, u8 *args, int args_len,
154 unsigned char *buf_recv, int data_len)
156 struct i2c_hid *ihid = i2c_get_clientdata(client);
157 union command *cmd = (union command *)ihid->cmdbuf;
159 struct i2c_msg msg[2];
162 int length = command->length;
163 bool wait = command->wait;
164 unsigned int registerIndex = command->registerIndex;
166 /* special case for hid_descr_cmd */
167 if (command == &hid_descr_cmd) {
168 cmd->c.reg = ihid->wHIDDescRegister;
170 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
171 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
175 cmd->c.opcode = command->opcode;
176 cmd->c.reportTypeID = reportID | reportType << 4;
179 memcpy(cmd->data + length, args, args_len);
182 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
184 msg[0].addr = client->addr;
185 msg[0].flags = client->flags & I2C_M_TEN;
187 msg[0].buf = cmd->data;
189 msg[1].addr = client->addr;
190 msg[1].flags = client->flags & I2C_M_TEN;
191 msg[1].flags |= I2C_M_RD;
192 msg[1].len = data_len;
193 msg[1].buf = buf_recv;
195 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
199 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
201 ret = i2c_transfer(client->adapter, msg, msg_num);
204 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
207 return ret < 0 ? ret : -EIO;
212 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
213 if (!wait_event_timeout(ihid->wait,
214 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
215 msecs_to_jiffies(5000)))
217 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
223 static int i2c_hid_command(struct i2c_client *client,
224 const struct i2c_hid_cmd *command,
225 unsigned char *buf_recv, int data_len)
227 return __i2c_hid_command(client, command, 0, 0, NULL, 0,
231 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
232 u8 reportID, unsigned char *buf_recv, int data_len)
234 struct i2c_hid *ihid = i2c_get_clientdata(client);
238 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
240 i2c_hid_dbg(ihid, "%s\n", __func__);
242 if (reportID >= 0x0F) {
243 args[args_len++] = reportID;
247 args[args_len++] = readRegister & 0xFF;
248 args[args_len++] = readRegister >> 8;
250 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
251 reportType, args, args_len, buf_recv, data_len);
253 dev_err(&client->dev,
254 "failed to retrieve report from device.\n");
262 * i2c_hid_set_or_send_report: forward an incoming report to the device
263 * @client: the i2c_client of the device
264 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
265 * @reportID: the report ID
266 * @buf: the actual data to transfer, without the report ID
268 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
270 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
271 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
273 struct i2c_hid *ihid = i2c_get_clientdata(client);
274 u8 *args = ihid->argsbuf;
275 const struct i2c_hid_cmd *hidcmd;
277 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
278 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
279 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
281 /* hid_hw_* already checked that data_len < HID_MAX_BUFFER_SIZE */
282 u16 size = 2 /* size */ +
283 (reportID ? 1 : 0) /* reportID */ +
285 int args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
286 2 /* dataRegister */ +
290 i2c_hid_dbg(ihid, "%s\n", __func__);
292 if (!use_data && maxOutputLength == 0)
295 if (reportID >= 0x0F) {
296 args[index++] = reportID;
301 * use the data register for feature reports or if the device does not
302 * support the output register
305 args[index++] = dataRegister & 0xFF;
306 args[index++] = dataRegister >> 8;
307 hidcmd = &hid_set_report_cmd;
309 args[index++] = outputRegister & 0xFF;
310 args[index++] = outputRegister >> 8;
311 hidcmd = &hid_no_cmd;
314 args[index++] = size & 0xFF;
315 args[index++] = size >> 8;
318 args[index++] = reportID;
320 memcpy(&args[index], buf, data_len);
322 ret = __i2c_hid_command(client, hidcmd, reportID,
323 reportType, args, args_len, NULL, 0);
325 dev_err(&client->dev, "failed to set a report to device.\n");
332 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
334 struct i2c_hid *ihid = i2c_get_clientdata(client);
337 i2c_hid_dbg(ihid, "%s\n", __func__);
339 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
340 0, NULL, 0, NULL, 0);
342 dev_err(&client->dev, "failed to change power setting.\n");
347 static int i2c_hid_hwreset(struct i2c_client *client)
349 struct i2c_hid *ihid = i2c_get_clientdata(client);
352 i2c_hid_dbg(ihid, "%s\n", __func__);
354 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
358 i2c_hid_dbg(ihid, "resetting...\n");
360 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
362 dev_err(&client->dev, "failed to reset device.\n");
363 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
370 static void i2c_hid_get_input(struct i2c_hid *ihid)
373 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
375 if (size > ihid->bufsize)
376 size = ihid->bufsize;
378 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
383 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
384 __func__, ret, size);
388 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
391 /* host or device initiated RESET completed */
392 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
393 wake_up(&ihid->wait);
397 if (ret_size > size) {
398 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
399 __func__, size, ret_size);
403 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
405 if (test_bit(I2C_HID_STARTED, &ihid->flags))
406 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
412 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
414 struct i2c_hid *ihid = dev_id;
416 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
419 i2c_hid_get_input(ihid);
424 static int i2c_hid_get_report_length(struct hid_report *report)
426 return ((report->size - 1) >> 3) + 1 +
427 report->device->report_enum[report->type].numbered + 2;
430 static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
433 struct hid_device *hid = report->device;
434 struct i2c_client *client = hid->driver_data;
435 struct i2c_hid *ihid = i2c_get_clientdata(client);
436 unsigned int size, ret_size;
438 size = i2c_hid_get_report_length(report);
439 if (i2c_hid_get_report(client,
440 report->type == HID_FEATURE_REPORT ? 0x03 : 0x01,
441 report->id, buffer, size))
444 i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, buffer);
446 ret_size = buffer[0] | (buffer[1] << 8);
448 if (ret_size != size) {
449 dev_err(&client->dev, "error in %s size:%d / ret_size:%d\n",
450 __func__, size, ret_size);
454 /* hid->driver_lock is held as we are in probe function,
455 * we just need to setup the input fields, so using
456 * hid_report_raw_event is safe. */
457 hid_report_raw_event(hid, report->type, buffer + 2, size - 2, 1);
461 * Initialize all reports
463 static void i2c_hid_init_reports(struct hid_device *hid)
465 struct hid_report *report;
466 struct i2c_client *client = hid->driver_data;
467 struct i2c_hid *ihid = i2c_get_clientdata(client);
468 u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
471 dev_err(&client->dev, "can not retrieve initial reports\n");
476 * The device must be powered on while we fetch initial reports
479 pm_runtime_get_sync(&client->dev);
481 list_for_each_entry(report,
482 &hid->report_enum[HID_FEATURE_REPORT].report_list, list)
483 i2c_hid_init_report(report, inbuf, ihid->bufsize);
485 pm_runtime_put(&client->dev);
491 * Traverse the supplied list of reports and find the longest
493 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
496 struct hid_report *report;
499 /* We should not rely on wMaxInputLength, as some devices may set it to
501 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
502 size = i2c_hid_get_report_length(report);
508 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
512 kfree(ihid->argsbuf);
517 ihid->argsbuf = NULL;
521 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
523 /* the worst case is computed from the set_report command with a
524 * reportID > 15 and the maximum report length */
525 int args_len = sizeof(__u8) + /* optional ReportID byte */
526 sizeof(__u16) + /* data register */
527 sizeof(__u16) + /* size of the report */
528 report_size; /* report */
530 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
531 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
532 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
533 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
535 if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
536 i2c_hid_free_buffers(ihid);
540 ihid->bufsize = report_size;
545 static int i2c_hid_get_raw_report(struct hid_device *hid,
546 unsigned char report_number, __u8 *buf, size_t count,
547 unsigned char report_type)
549 struct i2c_client *client = hid->driver_data;
550 struct i2c_hid *ihid = i2c_get_clientdata(client);
551 size_t ret_count, ask_count;
554 if (report_type == HID_OUTPUT_REPORT)
557 /* +2 bytes to include the size of the reply in the query buffer */
558 ask_count = min(count + 2, (size_t)ihid->bufsize);
560 ret = i2c_hid_get_report(client,
561 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
562 report_number, ihid->rawbuf, ask_count);
567 ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
572 ret_count = min(ret_count, ask_count);
574 /* The query buffer contains the size, dropping it in the reply */
575 count = min(count, ret_count - 2);
576 memcpy(buf, ihid->rawbuf + 2, count);
581 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
582 size_t count, unsigned char report_type, bool use_data)
584 struct i2c_client *client = hid->driver_data;
585 int report_id = buf[0];
588 if (report_type == HID_INPUT_REPORT)
596 ret = i2c_hid_set_or_send_report(client,
597 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
598 report_id, buf, count, use_data);
600 if (report_id && ret >= 0)
601 ret++; /* add report_id to the number of transfered bytes */
606 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
609 return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
613 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
614 __u8 *buf, size_t len, unsigned char rtype,
618 case HID_REQ_GET_REPORT:
619 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
620 case HID_REQ_SET_REPORT:
621 if (buf[0] != reportnum)
623 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
629 static int i2c_hid_parse(struct hid_device *hid)
631 struct i2c_client *client = hid->driver_data;
632 struct i2c_hid *ihid = i2c_get_clientdata(client);
633 struct i2c_hid_desc *hdesc = &ihid->hdesc;
639 i2c_hid_dbg(ihid, "entering %s\n", __func__);
641 rsize = le16_to_cpu(hdesc->wReportDescLength);
642 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
643 dbg_hid("weird size of report descriptor (%u)\n", rsize);
648 ret = i2c_hid_hwreset(client);
651 } while (tries-- > 0 && ret);
656 rdesc = kzalloc(rsize, GFP_KERNEL);
659 dbg_hid("couldn't allocate rdesc memory\n");
663 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
665 ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize);
667 hid_err(hid, "reading report descriptor failed\n");
672 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
674 ret = hid_parse_report(hid, rdesc, rsize);
677 dbg_hid("parsing report descriptor failed\n");
684 static int i2c_hid_start(struct hid_device *hid)
686 struct i2c_client *client = hid->driver_data;
687 struct i2c_hid *ihid = i2c_get_clientdata(client);
689 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
691 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
692 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
693 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
695 if (bufsize > ihid->bufsize) {
696 i2c_hid_free_buffers(ihid);
698 ret = i2c_hid_alloc_buffers(ihid, bufsize);
704 if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
705 i2c_hid_init_reports(hid);
710 static void i2c_hid_stop(struct hid_device *hid)
715 static int i2c_hid_open(struct hid_device *hid)
717 struct i2c_client *client = hid->driver_data;
718 struct i2c_hid *ihid = i2c_get_clientdata(client);
721 mutex_lock(&i2c_hid_open_mut);
723 ret = pm_runtime_get_sync(&client->dev);
728 set_bit(I2C_HID_STARTED, &ihid->flags);
731 mutex_unlock(&i2c_hid_open_mut);
732 return ret < 0 ? ret : 0;
735 static void i2c_hid_close(struct hid_device *hid)
737 struct i2c_client *client = hid->driver_data;
738 struct i2c_hid *ihid = i2c_get_clientdata(client);
740 /* protecting hid->open to make sure we don't restart
741 * data acquistion due to a resumption we no longer
744 mutex_lock(&i2c_hid_open_mut);
746 clear_bit(I2C_HID_STARTED, &ihid->flags);
748 /* Save some power */
749 pm_runtime_put(&client->dev);
751 mutex_unlock(&i2c_hid_open_mut);
754 static int i2c_hid_power(struct hid_device *hid, int lvl)
756 struct i2c_client *client = hid->driver_data;
757 struct i2c_hid *ihid = i2c_get_clientdata(client);
759 i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
763 pm_runtime_get_sync(&client->dev);
766 pm_runtime_put(&client->dev);
772 static struct hid_ll_driver i2c_hid_ll_driver = {
773 .parse = i2c_hid_parse,
774 .start = i2c_hid_start,
775 .stop = i2c_hid_stop,
776 .open = i2c_hid_open,
777 .close = i2c_hid_close,
778 .power = i2c_hid_power,
779 .output_report = i2c_hid_output_report,
780 .raw_request = i2c_hid_raw_request,
783 static int i2c_hid_init_irq(struct i2c_client *client)
785 struct i2c_hid *ihid = i2c_get_clientdata(client);
788 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
790 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
791 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
794 dev_warn(&client->dev,
795 "Could not register for %s interrupt, irq = %d,"
797 client->name, client->irq, ret);
805 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
807 struct i2c_client *client = ihid->client;
808 struct i2c_hid_desc *hdesc = &ihid->hdesc;
812 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
813 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
814 ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer,
815 sizeof(struct i2c_hid_desc));
817 dev_err(&client->dev, "hid_descr_cmd failed\n");
821 /* Validate the length of HID descriptor, the 4 first bytes:
822 * bytes 0-1 -> length
823 * bytes 2-3 -> bcdVersion (has to be 1.00) */
824 /* check bcdVersion == 1.0 */
825 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
826 dev_err(&client->dev,
827 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
828 le16_to_cpu(hdesc->bcdVersion));
832 /* Descriptor length should be 30 bytes as per the specification */
833 dsize = le16_to_cpu(hdesc->wHIDDescLength);
834 if (dsize != sizeof(struct i2c_hid_desc)) {
835 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
839 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
844 static int i2c_hid_acpi_pdata(struct i2c_client *client,
845 struct i2c_hid_platform_data *pdata)
847 static u8 i2c_hid_guid[] = {
848 0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45,
849 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE,
851 union acpi_object *obj;
852 struct acpi_device *adev;
855 handle = ACPI_HANDLE(&client->dev);
856 if (!handle || acpi_bus_get_device(handle, &adev))
859 obj = acpi_evaluate_dsm_typed(handle, i2c_hid_guid, 1, 1, NULL,
862 dev_err(&client->dev, "device _DSM execution failed\n");
866 pdata->hid_descriptor_address = obj->integer.value;
872 static const struct acpi_device_id i2c_hid_acpi_match[] = {
877 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
879 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
880 struct i2c_hid_platform_data *pdata)
887 static int i2c_hid_of_probe(struct i2c_client *client,
888 struct i2c_hid_platform_data *pdata)
890 struct device *dev = &client->dev;
894 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
896 dev_err(&client->dev, "HID register address not provided\n");
900 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
904 pdata->hid_descriptor_address = val;
909 static const struct of_device_id i2c_hid_of_match[] = {
910 { .compatible = "hid-over-i2c" },
913 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
915 static inline int i2c_hid_of_probe(struct i2c_client *client,
916 struct i2c_hid_platform_data *pdata)
922 static int i2c_hid_probe(struct i2c_client *client,
923 const struct i2c_device_id *dev_id)
926 struct i2c_hid *ihid;
927 struct hid_device *hid;
929 struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
931 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
934 dev_err(&client->dev,
935 "HID over i2c has not been provided an Int IRQ\n");
939 ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
943 if (client->dev.of_node) {
944 ret = i2c_hid_of_probe(client, &ihid->pdata);
947 } else if (!platform_data) {
948 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
950 dev_err(&client->dev,
951 "HID register address not provided\n");
955 ihid->pdata = *platform_data;
958 i2c_set_clientdata(client, ihid);
960 ihid->client = client;
962 hidRegister = ihid->pdata.hid_descriptor_address;
963 ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
965 init_waitqueue_head(&ihid->wait);
967 /* we need to allocate the command buffer without knowing the maximum
968 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
969 * real computation later. */
970 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
974 pm_runtime_get_noresume(&client->dev);
975 pm_runtime_set_active(&client->dev);
976 pm_runtime_enable(&client->dev);
978 ret = i2c_hid_fetch_hid_descriptor(ihid);
982 ret = i2c_hid_init_irq(client);
986 hid = hid_allocate_device();
994 hid->driver_data = client;
995 hid->ll_driver = &i2c_hid_ll_driver;
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);
1013 pm_runtime_put(&client->dev);
1017 hid_destroy_device(hid);
1020 free_irq(client->irq, ihid);
1023 pm_runtime_put_noidle(&client->dev);
1024 pm_runtime_disable(&client->dev);
1027 i2c_hid_free_buffers(ihid);
1032 static int i2c_hid_remove(struct i2c_client *client)
1034 struct i2c_hid *ihid = i2c_get_clientdata(client);
1035 struct hid_device *hid;
1037 pm_runtime_get_sync(&client->dev);
1038 pm_runtime_disable(&client->dev);
1039 pm_runtime_set_suspended(&client->dev);
1040 pm_runtime_put_noidle(&client->dev);
1043 hid_destroy_device(hid);
1045 free_irq(client->irq, ihid);
1048 i2c_hid_free_buffers(ihid);
1055 #ifdef CONFIG_PM_SLEEP
1056 static int i2c_hid_suspend(struct device *dev)
1058 struct i2c_client *client = to_i2c_client(dev);
1059 struct i2c_hid *ihid = i2c_get_clientdata(client);
1060 struct hid_device *hid = ihid->hid;
1063 disable_irq(client->irq);
1064 if (device_may_wakeup(&client->dev))
1065 enable_irq_wake(client->irq);
1067 if (hid->driver && hid->driver->suspend)
1068 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1070 /* Save some power */
1071 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1076 static int i2c_hid_resume(struct device *dev)
1079 struct i2c_client *client = to_i2c_client(dev);
1080 struct i2c_hid *ihid = i2c_get_clientdata(client);
1081 struct hid_device *hid = ihid->hid;
1083 enable_irq(client->irq);
1084 ret = i2c_hid_hwreset(client);
1088 if (device_may_wakeup(&client->dev))
1089 disable_irq_wake(client->irq);
1091 if (hid->driver && hid->driver->reset_resume) {
1092 ret = hid->driver->reset_resume(hid);
1101 static int i2c_hid_runtime_suspend(struct device *dev)
1103 struct i2c_client *client = to_i2c_client(dev);
1105 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1106 disable_irq(client->irq);
1110 static int i2c_hid_runtime_resume(struct device *dev)
1112 struct i2c_client *client = to_i2c_client(dev);
1114 enable_irq(client->irq);
1115 i2c_hid_set_power(client, I2C_HID_PWR_ON);
1120 static const struct dev_pm_ops i2c_hid_pm = {
1121 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1122 SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
1126 static const struct i2c_device_id i2c_hid_id_table[] = {
1130 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1133 static struct i2c_driver i2c_hid_driver = {
1136 .owner = THIS_MODULE,
1138 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1139 .of_match_table = of_match_ptr(i2c_hid_of_match),
1142 .probe = i2c_hid_probe,
1143 .remove = i2c_hid_remove,
1145 .id_table = i2c_hid_id_table,
1148 module_i2c_driver(i2c_hid_driver);
1150 MODULE_DESCRIPTION("HID over I2C core driver");
1151 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1152 MODULE_LICENSE("GPL");