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/irq.h>
26 #include <linux/delay.h>
27 #include <linux/slab.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>
41 #include <linux/regulator/consumer.h>
43 #include <linux/platform_data/i2c-hid.h>
45 #include "../hid-ids.h"
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)
52 #define I2C_HID_STARTED 0
53 #define I2C_HID_RESET_PENDING 1
54 #define I2C_HID_READ_PENDING 2
56 #define I2C_HID_PWR_ON 0x00
57 #define I2C_HID_PWR_SLEEP 0x01
61 module_param(debug
, bool, 0444);
62 MODULE_PARM_DESC(debug
, "print a lot of debug information");
64 #define i2c_hid_dbg(ihid, fmt, arg...) \
67 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
71 __le16 wHIDDescLength
;
73 __le16 wReportDescLength
;
74 __le16 wReportDescRegister
;
75 __le16 wInputRegister
;
76 __le16 wMaxInputLength
;
77 __le16 wOutputRegister
;
78 __le16 wMaxOutputLength
;
79 __le16 wCommandRegister
;
88 unsigned int registerIndex
;
103 #define I2C_HID_CMD(opcode_) \
104 .opcode = opcode_, .length = 4, \
105 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
107 /* fetch HID descriptor */
108 static const struct i2c_hid_cmd hid_descr_cmd
= { .length
= 2 };
109 /* fetch report descriptors */
110 static const struct i2c_hid_cmd hid_report_descr_cmd
= {
111 .registerIndex
= offsetof(struct i2c_hid_desc
,
112 wReportDescRegister
),
116 static const struct i2c_hid_cmd hid_reset_cmd
= { I2C_HID_CMD(0x01),
118 static const struct i2c_hid_cmd hid_get_report_cmd
= { I2C_HID_CMD(0x02) };
119 static const struct i2c_hid_cmd hid_set_report_cmd
= { I2C_HID_CMD(0x03) };
120 static const struct i2c_hid_cmd hid_set_power_cmd
= { I2C_HID_CMD(0x08) };
121 static const struct i2c_hid_cmd hid_no_cmd
= { .length
= 0 };
124 * These definitions are not used here, but are defined by the spec.
125 * Keeping them here for documentation purposes.
127 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
128 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
129 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
130 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
133 static DEFINE_MUTEX(i2c_hid_open_mut
);
135 /* The main device structure */
137 struct i2c_client
*client
; /* i2c client */
138 struct hid_device
*hid
; /* pointer to corresponding HID dev */
140 __u8 hdesc_buffer
[sizeof(struct i2c_hid_desc
)];
141 struct i2c_hid_desc hdesc
; /* the HID Descriptor */
143 __le16 wHIDDescRegister
; /* location of the i2c
144 * register of the HID
146 unsigned int bufsize
; /* i2c buffer size */
147 char *inbuf
; /* Input buffer */
148 char *rawbuf
; /* Raw Input buffer */
149 char *cmdbuf
; /* Command buffer */
150 char *argsbuf
; /* Command arguments buffer */
152 unsigned long flags
; /* device flags */
153 unsigned long quirks
; /* Various quirks */
155 wait_queue_head_t wait
; /* For waiting the interrupt */
157 struct i2c_hid_platform_data pdata
;
159 bool irq_wake_enabled
;
160 struct mutex reset_lock
;
163 static const struct i2c_hid_quirks
{
167 } i2c_hid_quirks
[] = {
168 { USB_VENDOR_ID_WEIDA
, USB_DEVICE_ID_WEIDA_8752
,
169 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV
},
170 { USB_VENDOR_ID_WEIDA
, USB_DEVICE_ID_WEIDA_8755
,
171 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV
},
172 { I2C_VENDOR_ID_HANTICK
, I2C_PRODUCT_ID_HANTICK_5288
,
173 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET
},
178 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
179 * @idVendor: the 16-bit vendor ID
180 * @idProduct: the 16-bit product ID
182 * Returns: a u32 quirks value.
184 static u32
i2c_hid_lookup_quirk(const u16 idVendor
, const u16 idProduct
)
189 for (n
= 0; i2c_hid_quirks
[n
].idVendor
; n
++)
190 if (i2c_hid_quirks
[n
].idVendor
== idVendor
&&
191 (i2c_hid_quirks
[n
].idProduct
== (__u16
)HID_ANY_ID
||
192 i2c_hid_quirks
[n
].idProduct
== idProduct
))
193 quirks
= i2c_hid_quirks
[n
].quirks
;
198 static int __i2c_hid_command(struct i2c_client
*client
,
199 const struct i2c_hid_cmd
*command
, u8 reportID
,
200 u8 reportType
, u8
*args
, int args_len
,
201 unsigned char *buf_recv
, int data_len
)
203 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
204 union command
*cmd
= (union command
*)ihid
->cmdbuf
;
206 struct i2c_msg msg
[2];
209 int length
= command
->length
;
210 bool wait
= command
->wait
;
211 unsigned int registerIndex
= command
->registerIndex
;
213 /* special case for hid_descr_cmd */
214 if (command
== &hid_descr_cmd
) {
215 cmd
->c
.reg
= ihid
->wHIDDescRegister
;
217 cmd
->data
[0] = ihid
->hdesc_buffer
[registerIndex
];
218 cmd
->data
[1] = ihid
->hdesc_buffer
[registerIndex
+ 1];
222 cmd
->c
.opcode
= command
->opcode
;
223 cmd
->c
.reportTypeID
= reportID
| reportType
<< 4;
226 memcpy(cmd
->data
+ length
, args
, args_len
);
229 i2c_hid_dbg(ihid
, "%s: cmd=%*ph\n", __func__
, length
, cmd
->data
);
231 msg
[0].addr
= client
->addr
;
232 msg
[0].flags
= client
->flags
& I2C_M_TEN
;
234 msg
[0].buf
= cmd
->data
;
236 msg
[1].addr
= client
->addr
;
237 msg
[1].flags
= client
->flags
& I2C_M_TEN
;
238 msg
[1].flags
|= I2C_M_RD
;
239 msg
[1].len
= data_len
;
240 msg
[1].buf
= buf_recv
;
242 set_bit(I2C_HID_READ_PENDING
, &ihid
->flags
);
246 set_bit(I2C_HID_RESET_PENDING
, &ihid
->flags
);
248 ret
= i2c_transfer(client
->adapter
, msg
, msg_num
);
251 clear_bit(I2C_HID_READ_PENDING
, &ihid
->flags
);
254 return ret
< 0 ? ret
: -EIO
;
258 if (wait
&& (ihid
->quirks
& I2C_HID_QUIRK_NO_IRQ_AFTER_RESET
)) {
261 i2c_hid_dbg(ihid
, "%s: waiting...\n", __func__
);
262 if (!wait_event_timeout(ihid
->wait
,
263 !test_bit(I2C_HID_RESET_PENDING
, &ihid
->flags
),
264 msecs_to_jiffies(5000)))
266 i2c_hid_dbg(ihid
, "%s: finished.\n", __func__
);
272 static int i2c_hid_command(struct i2c_client
*client
,
273 const struct i2c_hid_cmd
*command
,
274 unsigned char *buf_recv
, int data_len
)
276 return __i2c_hid_command(client
, command
, 0, 0, NULL
, 0,
280 static int i2c_hid_get_report(struct i2c_client
*client
, u8 reportType
,
281 u8 reportID
, unsigned char *buf_recv
, int data_len
)
283 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
287 u16 readRegister
= le16_to_cpu(ihid
->hdesc
.wDataRegister
);
289 i2c_hid_dbg(ihid
, "%s\n", __func__
);
291 if (reportID
>= 0x0F) {
292 args
[args_len
++] = reportID
;
296 args
[args_len
++] = readRegister
& 0xFF;
297 args
[args_len
++] = readRegister
>> 8;
299 ret
= __i2c_hid_command(client
, &hid_get_report_cmd
, reportID
,
300 reportType
, args
, args_len
, buf_recv
, data_len
);
302 dev_err(&client
->dev
,
303 "failed to retrieve report from device.\n");
311 * i2c_hid_set_or_send_report: forward an incoming report to the device
312 * @client: the i2c_client of the device
313 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
314 * @reportID: the report ID
315 * @buf: the actual data to transfer, without the report ID
317 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
319 static int i2c_hid_set_or_send_report(struct i2c_client
*client
, u8 reportType
,
320 u8 reportID
, unsigned char *buf
, size_t data_len
, bool use_data
)
322 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
323 u8
*args
= ihid
->argsbuf
;
324 const struct i2c_hid_cmd
*hidcmd
;
326 u16 dataRegister
= le16_to_cpu(ihid
->hdesc
.wDataRegister
);
327 u16 outputRegister
= le16_to_cpu(ihid
->hdesc
.wOutputRegister
);
328 u16 maxOutputLength
= le16_to_cpu(ihid
->hdesc
.wMaxOutputLength
);
333 i2c_hid_dbg(ihid
, "%s\n", __func__
);
335 if (data_len
> ihid
->bufsize
)
338 size
= 2 /* size */ +
339 (reportID
? 1 : 0) /* reportID */ +
341 args_len
= (reportID
>= 0x0F ? 1 : 0) /* optional third byte */ +
342 2 /* dataRegister */ +
345 if (!use_data
&& maxOutputLength
== 0)
348 if (reportID
>= 0x0F) {
349 args
[index
++] = reportID
;
354 * use the data register for feature reports or if the device does not
355 * support the output register
358 args
[index
++] = dataRegister
& 0xFF;
359 args
[index
++] = dataRegister
>> 8;
360 hidcmd
= &hid_set_report_cmd
;
362 args
[index
++] = outputRegister
& 0xFF;
363 args
[index
++] = outputRegister
>> 8;
364 hidcmd
= &hid_no_cmd
;
367 args
[index
++] = size
& 0xFF;
368 args
[index
++] = size
>> 8;
371 args
[index
++] = reportID
;
373 memcpy(&args
[index
], buf
, data_len
);
375 ret
= __i2c_hid_command(client
, hidcmd
, reportID
,
376 reportType
, args
, args_len
, NULL
, 0);
378 dev_err(&client
->dev
, "failed to set a report to device.\n");
385 static int i2c_hid_set_power(struct i2c_client
*client
, int power_state
)
387 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
390 i2c_hid_dbg(ihid
, "%s\n", __func__
);
393 * Some devices require to send a command to wakeup before power on.
394 * The call will get a return value (EREMOTEIO) but device will be
395 * triggered and activated. After that, it goes like a normal device.
397 if (power_state
== I2C_HID_PWR_ON
&&
398 ihid
->quirks
& I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV
) {
399 ret
= i2c_hid_command(client
, &hid_set_power_cmd
, NULL
, 0);
401 /* Device was already activated */
406 ret
= __i2c_hid_command(client
, &hid_set_power_cmd
, power_state
,
407 0, NULL
, 0, NULL
, 0);
410 dev_err(&client
->dev
, "failed to change power setting.\n");
416 static int i2c_hid_hwreset(struct i2c_client
*client
)
418 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
421 i2c_hid_dbg(ihid
, "%s\n", __func__
);
424 * This prevents sending feature reports while the device is
425 * being reset. Otherwise we may lose the reset complete
428 mutex_lock(&ihid
->reset_lock
);
430 ret
= i2c_hid_set_power(client
, I2C_HID_PWR_ON
);
435 * The HID over I2C specification states that if a DEVICE needs time
436 * after the PWR_ON request, it should utilise CLOCK stretching.
437 * However, it has been observered that the Windows driver provides a
438 * 1ms sleep between the PWR_ON and RESET requests and that some devices
441 usleep_range(1000, 5000);
443 i2c_hid_dbg(ihid
, "resetting...\n");
445 ret
= i2c_hid_command(client
, &hid_reset_cmd
, NULL
, 0);
447 dev_err(&client
->dev
, "failed to reset device.\n");
448 i2c_hid_set_power(client
, I2C_HID_PWR_SLEEP
);
452 mutex_unlock(&ihid
->reset_lock
);
456 static void i2c_hid_get_input(struct i2c_hid
*ihid
)
459 int size
= le16_to_cpu(ihid
->hdesc
.wMaxInputLength
);
461 if (size
> ihid
->bufsize
)
462 size
= ihid
->bufsize
;
464 ret
= i2c_master_recv(ihid
->client
, ihid
->inbuf
, size
);
469 dev_err(&ihid
->client
->dev
, "%s: got %d data instead of %d\n",
470 __func__
, ret
, size
);
474 ret_size
= ihid
->inbuf
[0] | ihid
->inbuf
[1] << 8;
477 /* host or device initiated RESET completed */
478 if (test_and_clear_bit(I2C_HID_RESET_PENDING
, &ihid
->flags
))
479 wake_up(&ihid
->wait
);
483 if (ret_size
> size
) {
484 dev_err(&ihid
->client
->dev
, "%s: incomplete report (%d/%d)\n",
485 __func__
, size
, ret_size
);
489 i2c_hid_dbg(ihid
, "input: %*ph\n", ret_size
, ihid
->inbuf
);
491 if (test_bit(I2C_HID_STARTED
, &ihid
->flags
))
492 hid_input_report(ihid
->hid
, HID_INPUT_REPORT
, ihid
->inbuf
+ 2,
498 static irqreturn_t
i2c_hid_irq(int irq
, void *dev_id
)
500 struct i2c_hid
*ihid
= dev_id
;
502 if (test_bit(I2C_HID_READ_PENDING
, &ihid
->flags
))
505 i2c_hid_get_input(ihid
);
510 static int i2c_hid_get_report_length(struct hid_report
*report
)
512 return ((report
->size
- 1) >> 3) + 1 +
513 report
->device
->report_enum
[report
->type
].numbered
+ 2;
517 * Traverse the supplied list of reports and find the longest
519 static void i2c_hid_find_max_report(struct hid_device
*hid
, unsigned int type
,
522 struct hid_report
*report
;
525 /* We should not rely on wMaxInputLength, as some devices may set it to
527 list_for_each_entry(report
, &hid
->report_enum
[type
].report_list
, list
) {
528 size
= i2c_hid_get_report_length(report
);
534 static void i2c_hid_free_buffers(struct i2c_hid
*ihid
)
538 kfree(ihid
->argsbuf
);
543 ihid
->argsbuf
= NULL
;
547 static int i2c_hid_alloc_buffers(struct i2c_hid
*ihid
, size_t report_size
)
549 /* the worst case is computed from the set_report command with a
550 * reportID > 15 and the maximum report length */
551 int args_len
= sizeof(__u8
) + /* ReportID */
552 sizeof(__u8
) + /* optional ReportID byte */
553 sizeof(__u16
) + /* data register */
554 sizeof(__u16
) + /* size of the report */
555 report_size
; /* report */
557 ihid
->inbuf
= kzalloc(report_size
, GFP_KERNEL
);
558 ihid
->rawbuf
= kzalloc(report_size
, GFP_KERNEL
);
559 ihid
->argsbuf
= kzalloc(args_len
, GFP_KERNEL
);
560 ihid
->cmdbuf
= kzalloc(sizeof(union command
) + args_len
, GFP_KERNEL
);
562 if (!ihid
->inbuf
|| !ihid
->rawbuf
|| !ihid
->argsbuf
|| !ihid
->cmdbuf
) {
563 i2c_hid_free_buffers(ihid
);
567 ihid
->bufsize
= report_size
;
572 static int i2c_hid_get_raw_report(struct hid_device
*hid
,
573 unsigned char report_number
, __u8
*buf
, size_t count
,
574 unsigned char report_type
)
576 struct i2c_client
*client
= hid
->driver_data
;
577 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
578 size_t ret_count
, ask_count
;
581 if (report_type
== HID_OUTPUT_REPORT
)
584 /* +2 bytes to include the size of the reply in the query buffer */
585 ask_count
= min(count
+ 2, (size_t)ihid
->bufsize
);
587 ret
= i2c_hid_get_report(client
,
588 report_type
== HID_FEATURE_REPORT
? 0x03 : 0x01,
589 report_number
, ihid
->rawbuf
, ask_count
);
594 ret_count
= ihid
->rawbuf
[0] | (ihid
->rawbuf
[1] << 8);
599 ret_count
= min(ret_count
, ask_count
);
601 /* The query buffer contains the size, dropping it in the reply */
602 count
= min(count
, ret_count
- 2);
603 memcpy(buf
, ihid
->rawbuf
+ 2, count
);
608 static int i2c_hid_output_raw_report(struct hid_device
*hid
, __u8
*buf
,
609 size_t count
, unsigned char report_type
, bool use_data
)
611 struct i2c_client
*client
= hid
->driver_data
;
612 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
613 int report_id
= buf
[0];
616 if (report_type
== HID_INPUT_REPORT
)
619 mutex_lock(&ihid
->reset_lock
);
626 ret
= i2c_hid_set_or_send_report(client
,
627 report_type
== HID_FEATURE_REPORT
? 0x03 : 0x02,
628 report_id
, buf
, count
, use_data
);
630 if (report_id
&& ret
>= 0)
631 ret
++; /* add report_id to the number of transfered bytes */
633 mutex_unlock(&ihid
->reset_lock
);
638 static int i2c_hid_output_report(struct hid_device
*hid
, __u8
*buf
,
641 return i2c_hid_output_raw_report(hid
, buf
, count
, HID_OUTPUT_REPORT
,
645 static int i2c_hid_raw_request(struct hid_device
*hid
, unsigned char reportnum
,
646 __u8
*buf
, size_t len
, unsigned char rtype
,
650 case HID_REQ_GET_REPORT
:
651 return i2c_hid_get_raw_report(hid
, reportnum
, buf
, len
, rtype
);
652 case HID_REQ_SET_REPORT
:
653 if (buf
[0] != reportnum
)
655 return i2c_hid_output_raw_report(hid
, buf
, len
, rtype
, true);
661 static int i2c_hid_parse(struct hid_device
*hid
)
663 struct i2c_client
*client
= hid
->driver_data
;
664 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
665 struct i2c_hid_desc
*hdesc
= &ihid
->hdesc
;
671 i2c_hid_dbg(ihid
, "entering %s\n", __func__
);
673 rsize
= le16_to_cpu(hdesc
->wReportDescLength
);
674 if (!rsize
|| rsize
> HID_MAX_DESCRIPTOR_SIZE
) {
675 dbg_hid("weird size of report descriptor (%u)\n", rsize
);
680 ret
= i2c_hid_hwreset(client
);
683 } while (tries
-- > 0 && ret
);
688 rdesc
= kzalloc(rsize
, GFP_KERNEL
);
691 dbg_hid("couldn't allocate rdesc memory\n");
695 i2c_hid_dbg(ihid
, "asking HID report descriptor\n");
697 ret
= i2c_hid_command(client
, &hid_report_descr_cmd
, rdesc
, rsize
);
699 hid_err(hid
, "reading report descriptor failed\n");
704 i2c_hid_dbg(ihid
, "Report Descriptor: %*ph\n", rsize
, rdesc
);
706 ret
= hid_parse_report(hid
, rdesc
, rsize
);
709 dbg_hid("parsing report descriptor failed\n");
716 static int i2c_hid_start(struct hid_device
*hid
)
718 struct i2c_client
*client
= hid
->driver_data
;
719 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
721 unsigned int bufsize
= HID_MIN_BUFFER_SIZE
;
723 i2c_hid_find_max_report(hid
, HID_INPUT_REPORT
, &bufsize
);
724 i2c_hid_find_max_report(hid
, HID_OUTPUT_REPORT
, &bufsize
);
725 i2c_hid_find_max_report(hid
, HID_FEATURE_REPORT
, &bufsize
);
727 if (bufsize
> ihid
->bufsize
) {
728 disable_irq(client
->irq
);
729 i2c_hid_free_buffers(ihid
);
731 ret
= i2c_hid_alloc_buffers(ihid
, bufsize
);
732 enable_irq(client
->irq
);
741 static void i2c_hid_stop(struct hid_device
*hid
)
746 static int i2c_hid_open(struct hid_device
*hid
)
748 struct i2c_client
*client
= hid
->driver_data
;
749 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
752 ret
= pm_runtime_get_sync(&client
->dev
);
756 set_bit(I2C_HID_STARTED
, &ihid
->flags
);
760 static void i2c_hid_close(struct hid_device
*hid
)
762 struct i2c_client
*client
= hid
->driver_data
;
763 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
765 clear_bit(I2C_HID_STARTED
, &ihid
->flags
);
767 /* Save some power */
768 pm_runtime_put(&client
->dev
);
771 static int i2c_hid_power(struct hid_device
*hid
, int lvl
)
773 struct i2c_client
*client
= hid
->driver_data
;
774 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
776 i2c_hid_dbg(ihid
, "%s lvl:%d\n", __func__
, lvl
);
780 pm_runtime_get_sync(&client
->dev
);
783 pm_runtime_put(&client
->dev
);
789 struct hid_ll_driver i2c_hid_ll_driver
= {
790 .parse
= i2c_hid_parse
,
791 .start
= i2c_hid_start
,
792 .stop
= i2c_hid_stop
,
793 .open
= i2c_hid_open
,
794 .close
= i2c_hid_close
,
795 .power
= i2c_hid_power
,
796 .output_report
= i2c_hid_output_report
,
797 .raw_request
= i2c_hid_raw_request
,
799 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver
);
801 static int i2c_hid_init_irq(struct i2c_client
*client
)
803 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
804 unsigned long irqflags
= 0;
807 dev_dbg(&client
->dev
, "Requesting IRQ: %d\n", client
->irq
);
809 if (!irq_get_trigger_type(client
->irq
))
810 irqflags
= IRQF_TRIGGER_LOW
;
812 ret
= request_threaded_irq(client
->irq
, NULL
, i2c_hid_irq
,
813 irqflags
| IRQF_ONESHOT
, client
->name
, ihid
);
815 dev_warn(&client
->dev
,
816 "Could not register for %s interrupt, irq = %d,"
818 client
->name
, client
->irq
, ret
);
826 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid
*ihid
)
828 struct i2c_client
*client
= ihid
->client
;
829 struct i2c_hid_desc
*hdesc
= &ihid
->hdesc
;
833 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
834 i2c_hid_dbg(ihid
, "Fetching the HID descriptor\n");
835 ret
= i2c_hid_command(client
, &hid_descr_cmd
, ihid
->hdesc_buffer
,
836 sizeof(struct i2c_hid_desc
));
838 dev_err(&client
->dev
, "hid_descr_cmd failed\n");
842 /* Validate the length of HID descriptor, the 4 first bytes:
843 * bytes 0-1 -> length
844 * bytes 2-3 -> bcdVersion (has to be 1.00) */
845 /* check bcdVersion == 1.0 */
846 if (le16_to_cpu(hdesc
->bcdVersion
) != 0x0100) {
847 dev_err(&client
->dev
,
848 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
849 le16_to_cpu(hdesc
->bcdVersion
));
853 /* Descriptor length should be 30 bytes as per the specification */
854 dsize
= le16_to_cpu(hdesc
->wHIDDescLength
);
855 if (dsize
!= sizeof(struct i2c_hid_desc
)) {
856 dev_err(&client
->dev
, "weird size of HID descriptor (%u)\n",
860 i2c_hid_dbg(ihid
, "HID Descriptor: %*ph\n", dsize
, ihid
->hdesc_buffer
);
865 static int i2c_hid_acpi_pdata(struct i2c_client
*client
,
866 struct i2c_hid_platform_data
*pdata
)
868 static guid_t i2c_hid_guid
=
869 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
870 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
871 union acpi_object
*obj
;
872 struct acpi_device
*adev
;
875 handle
= ACPI_HANDLE(&client
->dev
);
876 if (!handle
|| acpi_bus_get_device(handle
, &adev
))
879 obj
= acpi_evaluate_dsm_typed(handle
, &i2c_hid_guid
, 1, 1, NULL
,
882 dev_err(&client
->dev
, "device _DSM execution failed\n");
886 pdata
->hid_descriptor_address
= obj
->integer
.value
;
892 static void i2c_hid_acpi_fix_up_power(struct device
*dev
)
894 acpi_handle handle
= ACPI_HANDLE(dev
);
895 struct acpi_device
*adev
;
897 if (handle
&& acpi_bus_get_device(handle
, &adev
) == 0)
898 acpi_device_fix_up_power(adev
);
901 static const struct acpi_device_id i2c_hid_acpi_match
[] = {
906 MODULE_DEVICE_TABLE(acpi
, i2c_hid_acpi_match
);
908 static inline int i2c_hid_acpi_pdata(struct i2c_client
*client
,
909 struct i2c_hid_platform_data
*pdata
)
914 static inline void i2c_hid_acpi_fix_up_power(struct device
*dev
) {}
918 static int i2c_hid_of_probe(struct i2c_client
*client
,
919 struct i2c_hid_platform_data
*pdata
)
921 struct device
*dev
= &client
->dev
;
925 ret
= of_property_read_u32(dev
->of_node
, "hid-descr-addr", &val
);
927 dev_err(&client
->dev
, "HID register address not provided\n");
931 dev_err(&client
->dev
, "Bad HID register address: 0x%08x\n",
935 pdata
->hid_descriptor_address
= val
;
937 ret
= of_property_read_u32(dev
->of_node
, "post-power-on-delay-ms",
940 pdata
->post_power_delay_ms
= val
;
945 static const struct of_device_id i2c_hid_of_match
[] = {
946 { .compatible
= "hid-over-i2c" },
949 MODULE_DEVICE_TABLE(of
, i2c_hid_of_match
);
951 static inline int i2c_hid_of_probe(struct i2c_client
*client
,
952 struct i2c_hid_platform_data
*pdata
)
958 static int i2c_hid_probe(struct i2c_client
*client
,
959 const struct i2c_device_id
*dev_id
)
962 struct i2c_hid
*ihid
;
963 struct hid_device
*hid
;
965 struct i2c_hid_platform_data
*platform_data
= client
->dev
.platform_data
;
967 dbg_hid("HID probe called for i2c 0x%02x\n", client
->addr
);
970 dev_err(&client
->dev
,
971 "HID over i2c has not been provided an Int IRQ\n");
975 if (client
->irq
< 0) {
976 if (client
->irq
!= -EPROBE_DEFER
)
977 dev_err(&client
->dev
,
978 "HID over i2c doesn't have a valid IRQ\n");
982 ihid
= kzalloc(sizeof(struct i2c_hid
), GFP_KERNEL
);
986 if (client
->dev
.of_node
) {
987 ret
= i2c_hid_of_probe(client
, &ihid
->pdata
);
990 } else if (!platform_data
) {
991 ret
= i2c_hid_acpi_pdata(client
, &ihid
->pdata
);
993 dev_err(&client
->dev
,
994 "HID register address not provided\n");
998 ihid
->pdata
= *platform_data
;
1001 ihid
->pdata
.supply
= devm_regulator_get(&client
->dev
, "vdd");
1002 if (IS_ERR(ihid
->pdata
.supply
)) {
1003 ret
= PTR_ERR(ihid
->pdata
.supply
);
1004 if (ret
!= -EPROBE_DEFER
)
1005 dev_err(&client
->dev
, "Failed to get regulator: %d\n",
1010 ret
= regulator_enable(ihid
->pdata
.supply
);
1012 dev_err(&client
->dev
, "Failed to enable regulator: %d\n",
1016 if (ihid
->pdata
.post_power_delay_ms
)
1017 msleep(ihid
->pdata
.post_power_delay_ms
);
1019 i2c_set_clientdata(client
, ihid
);
1021 ihid
->client
= client
;
1023 hidRegister
= ihid
->pdata
.hid_descriptor_address
;
1024 ihid
->wHIDDescRegister
= cpu_to_le16(hidRegister
);
1026 init_waitqueue_head(&ihid
->wait
);
1027 mutex_init(&ihid
->reset_lock
);
1029 /* we need to allocate the command buffer without knowing the maximum
1030 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1031 * real computation later. */
1032 ret
= i2c_hid_alloc_buffers(ihid
, HID_MIN_BUFFER_SIZE
);
1036 i2c_hid_acpi_fix_up_power(&client
->dev
);
1038 pm_runtime_get_noresume(&client
->dev
);
1039 pm_runtime_set_active(&client
->dev
);
1040 pm_runtime_enable(&client
->dev
);
1041 device_enable_async_suspend(&client
->dev
);
1043 ret
= i2c_hid_fetch_hid_descriptor(ihid
);
1047 ret
= i2c_hid_init_irq(client
);
1051 hid
= hid_allocate_device();
1059 hid
->driver_data
= client
;
1060 hid
->ll_driver
= &i2c_hid_ll_driver
;
1061 hid
->dev
.parent
= &client
->dev
;
1063 hid
->version
= le16_to_cpu(ihid
->hdesc
.bcdVersion
);
1064 hid
->vendor
= le16_to_cpu(ihid
->hdesc
.wVendorID
);
1065 hid
->product
= le16_to_cpu(ihid
->hdesc
.wProductID
);
1067 snprintf(hid
->name
, sizeof(hid
->name
), "%s %04hX:%04hX",
1068 client
->name
, hid
->vendor
, hid
->product
);
1069 strlcpy(hid
->phys
, dev_name(&client
->dev
), sizeof(hid
->phys
));
1071 ihid
->quirks
= i2c_hid_lookup_quirk(hid
->vendor
, hid
->product
);
1073 ret
= hid_add_device(hid
);
1076 hid_err(client
, "can't add hid device: %d\n", ret
);
1080 pm_runtime_put(&client
->dev
);
1084 hid_destroy_device(hid
);
1087 free_irq(client
->irq
, ihid
);
1090 pm_runtime_put_noidle(&client
->dev
);
1091 pm_runtime_disable(&client
->dev
);
1094 regulator_disable(ihid
->pdata
.supply
);
1097 i2c_hid_free_buffers(ihid
);
1102 static int i2c_hid_remove(struct i2c_client
*client
)
1104 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
1105 struct hid_device
*hid
;
1107 pm_runtime_get_sync(&client
->dev
);
1108 pm_runtime_disable(&client
->dev
);
1109 pm_runtime_set_suspended(&client
->dev
);
1110 pm_runtime_put_noidle(&client
->dev
);
1113 hid_destroy_device(hid
);
1115 free_irq(client
->irq
, ihid
);
1118 i2c_hid_free_buffers(ihid
);
1120 regulator_disable(ihid
->pdata
.supply
);
1127 static void i2c_hid_shutdown(struct i2c_client
*client
)
1129 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
1131 i2c_hid_set_power(client
, I2C_HID_PWR_SLEEP
);
1132 free_irq(client
->irq
, ihid
);
1135 #ifdef CONFIG_PM_SLEEP
1136 static int i2c_hid_suspend(struct device
*dev
)
1138 struct i2c_client
*client
= to_i2c_client(dev
);
1139 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
1140 struct hid_device
*hid
= ihid
->hid
;
1144 if (hid
->driver
&& hid
->driver
->suspend
) {
1146 * Wake up the device so that IO issues in
1147 * HID driver's suspend code can succeed.
1149 ret
= pm_runtime_resume(dev
);
1153 ret
= hid
->driver
->suspend(hid
, PMSG_SUSPEND
);
1158 if (!pm_runtime_suspended(dev
)) {
1159 /* Save some power */
1160 i2c_hid_set_power(client
, I2C_HID_PWR_SLEEP
);
1162 disable_irq(client
->irq
);
1165 if (device_may_wakeup(&client
->dev
)) {
1166 wake_status
= enable_irq_wake(client
->irq
);
1168 ihid
->irq_wake_enabled
= true;
1170 hid_warn(hid
, "Failed to enable irq wake: %d\n",
1173 ret
= regulator_disable(ihid
->pdata
.supply
);
1175 hid_warn(hid
, "Failed to disable supply: %d\n", ret
);
1181 static int i2c_hid_resume(struct device
*dev
)
1184 struct i2c_client
*client
= to_i2c_client(dev
);
1185 struct i2c_hid
*ihid
= i2c_get_clientdata(client
);
1186 struct hid_device
*hid
= ihid
->hid
;
1189 if (!device_may_wakeup(&client
->dev
)) {
1190 ret
= regulator_enable(ihid
->pdata
.supply
);
1192 hid_warn(hid
, "Failed to enable supply: %d\n", ret
);
1193 if (ihid
->pdata
.post_power_delay_ms
)
1194 msleep(ihid
->pdata
.post_power_delay_ms
);
1195 } else if (ihid
->irq_wake_enabled
) {
1196 wake_status
= disable_irq_wake(client
->irq
);
1198 ihid
->irq_wake_enabled
= false;
1200 hid_warn(hid
, "Failed to disable irq wake: %d\n",
1204 /* We'll resume to full power */
1205 pm_runtime_disable(dev
);
1206 pm_runtime_set_active(dev
);
1207 pm_runtime_enable(dev
);
1209 enable_irq(client
->irq
);
1210 ret
= i2c_hid_hwreset(client
);
1214 if (hid
->driver
&& hid
->driver
->reset_resume
) {
1215 ret
= hid
->driver
->reset_resume(hid
);
1224 static int i2c_hid_runtime_suspend(struct device
*dev
)
1226 struct i2c_client
*client
= to_i2c_client(dev
);
1228 i2c_hid_set_power(client
, I2C_HID_PWR_SLEEP
);
1229 disable_irq(client
->irq
);
1233 static int i2c_hid_runtime_resume(struct device
*dev
)
1235 struct i2c_client
*client
= to_i2c_client(dev
);
1237 enable_irq(client
->irq
);
1238 i2c_hid_set_power(client
, I2C_HID_PWR_ON
);
1243 static const struct dev_pm_ops i2c_hid_pm
= {
1244 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend
, i2c_hid_resume
)
1245 SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend
, i2c_hid_runtime_resume
,
1249 static const struct i2c_device_id i2c_hid_id_table
[] = {
1251 { "hid-over-i2c", 0 },
1254 MODULE_DEVICE_TABLE(i2c
, i2c_hid_id_table
);
1257 static struct i2c_driver i2c_hid_driver
= {
1261 .acpi_match_table
= ACPI_PTR(i2c_hid_acpi_match
),
1262 .of_match_table
= of_match_ptr(i2c_hid_of_match
),
1265 .probe
= i2c_hid_probe
,
1266 .remove
= i2c_hid_remove
,
1267 .shutdown
= i2c_hid_shutdown
,
1268 .id_table
= i2c_hid_id_table
,
1271 module_i2c_driver(i2c_hid_driver
);
1273 MODULE_DESCRIPTION("HID over I2C core driver");
1274 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1275 MODULE_LICENSE("GPL");