2 * This file is part of the libsigrok project.
4 * Copyright (C) 2017-2019 Gerhard Sittig <gerhard.sittig@gmx.net>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include <libsigrok/libsigrok.h>
26 #include "libsigrok-internal.h"
27 #include "serial_hid.h"
31 #include <windows.h> /* for HANDLE */
35 #define LOG_PREFIX "serial-hid"
38 #ifdef HAVE_SERIAL_COMM
43 * Serial port handling, HIDAPI library specific support code.
47 * @defgroup grp_serial_hid Serial port handling, HID group
49 * Make serial-over-HID communication appear like a regular serial port.
55 /* {{{ helper routines */
57 /* Strip off parity bits for "odd" data bit counts like in 7e1 frames. */
58 static void ser_hid_mask_databits(struct sr_serial_dev_inst *serial,
59 uint8_t *data, size_t len)
65 if ((serial->comm_params.data_bits % 8) == 0)
68 mask32 = (1UL << serial->comm_params.data_bits) - 1;
70 for (idx = 0; idx < len; idx++)
75 /* {{{ open/close/list/find HIDAPI connection, exchange HID requests and data */
78 * Convert a HIDAPI path (which depends on the target platform, and may
79 * depend on one of several available API variants on that platform) to
80 * something that is usable as a "port name" in conn= specs.
82 * Since conn= is passed with -d where multiple options (among them conn=)
83 * are separated by colons, port names themselves cannot contain colons.
85 * Just replace colons by a period in the simple case (Linux platform,
86 * hidapi-libusb implementation, bus/address/interface). Prefix the
87 * HIDAPI path in the complex cases (Linux hidapi-hidraw, Windows, Mac).
88 * Paths with colons outside of libusb based implementations are unhandled
89 * here, but were not yet seen on any sigrok supported platform either.
90 * So just reject them.
92 static char *get_hidapi_path_copy(const char *path)
94 static const char *accept = "0123456789abcdefABCDEF:";
95 static const char *keep = "0123456789abcdefABCDEF";
101 has_colon = strchr(path, ':') != NULL;
102 is_hex_colon = strspn(path, accept) == strlen(path);
103 if (has_colon && !is_hex_colon) {
104 sr_err("Unsupported HIDAPI path format: %s", path);
108 name = g_strdup_printf("%s%s", SER_HID_USB_PREFIX, path);
109 g_strcanon(name + strlen(SER_HID_USB_PREFIX), keep, '.');
111 name = g_strdup_printf("%s%s", SER_HID_RAW_PREFIX, path);
118 * Undo the port name construction that was done during scan. Extract
119 * the HIDAPI path from a conn= input spec (the part after the hid/
120 * prefix and chip type).
122 * Strip off the "raw" prefix, or undo colon substitution. See @ref
123 * get_hidapi_path_copy() for details.
125 static const char *extract_hidapi_path(char *buffer)
127 static const char *keep = "0123456789abcdefABCDEF:";
135 if (strncmp(p, SER_HID_RAW_PREFIX, strlen(SER_HID_RAW_PREFIX)) == 0) {
136 p += strlen(SER_HID_RAW_PREFIX);
139 if (strncmp(p, SER_HID_USB_PREFIX, strlen(SER_HID_USB_PREFIX)) == 0) {
140 p += strlen(SER_HID_USB_PREFIX);
141 g_strcanon(buffer, keep, ':');
149 * The HIDAPI specific list() callback, invoked by common serial.c code.
150 * Enumerate all devices (no VID:PID is involved).
151 * Invoke an 'append' callback with "path" and "name".
153 static GSList *ser_hid_hidapi_list(GSList *list, sr_ser_list_append_t append)
155 struct hid_device_info *devs, *curdev;
156 const char *chipname;
158 wchar_t *manuf, *prod, *serno;
162 devs = hid_enumerate(0x0000, 0x0000);
163 for (curdev = devs; curdev; curdev = curdev->next) {
165 * Determine the chip name from VID:PID (if it's one of
166 * the supported types with an ID known to us).
168 vid = curdev->vendor_id;
169 pid = curdev->product_id;
170 chipname = ser_hid_chip_find_name_vid_pid(vid, pid);
175 * Prefix port names such that open() calls with this
176 * conn= spec will end up here and contain all details
177 * that are essential for processing.
179 path = get_hidapi_path_copy(curdev->path);
182 name = g_strdup_printf("%s/%s/%s",
183 SER_HID_CONN_PREFIX, chipname, path);
187 * Print whatever information was available. Construct
188 * the description text from pieces. Absence of fields
189 * is not fatal, we have seen perfectly usable cables
190 * that only had a VID and PID (permissions were not an
193 manuf = curdev->manufacturer_string;
194 prod = curdev->product_string;
195 serno = curdev->serial_number;
196 vid = curdev->vendor_id;
197 pid = curdev->product_id;
198 desc = g_string_sized_new(128);
199 g_string_append_printf(desc, "HID");
200 if (manuf && wcslen(manuf) != 0)
201 g_string_append_printf(desc, " %ls", manuf);
202 if (prod && wcslen(prod) != 0)
203 g_string_append_printf(desc, " %ls", prod);
204 if (serno && wcslen(serno) != 0)
205 g_string_append_printf(desc, " %ls", serno);
207 g_string_append_printf(desc, " [%04hx.%04hx]", vid, pid);
208 list = append(list, name, desc->str);
209 g_string_free(desc, TRUE);
212 hid_free_enumeration(devs);
218 * The HIDAPI specific find_usb() callback, invoked by common serial.c code.
219 * Enumerate devices for the specified VID:PID pair.
220 * Invoke an "append" callback with 'path' for the device.
222 static GSList *ser_hid_hidapi_find_usb(GSList *list, sr_ser_find_append_t append,
223 uint16_t vendor_id, uint16_t product_id)
225 struct hid_device_info *devs, *curdev;
228 devs = hid_enumerate(vendor_id, product_id);
229 for (curdev = devs; curdev; curdev = curdev->next) {
231 list = append(list, name);
233 hid_free_enumeration(devs);
238 /* Get the serial number of a device specified by path. */
239 static int ser_hid_hidapi_get_serno(const char *path, char *buf, size_t blen)
249 usbpath = g_strdup(path);
250 hidpath = extract_hidapi_path(usbpath);
251 dev = hidpath ? hid_open_path(hidpath) : NULL;
256 serno_wch = g_malloc0(blen * sizeof(*serno_wch));
257 rc = hid_get_serial_number_string(dev, serno_wch, blen - 1);
264 snprintf(buf, blen, "%ls", serno_wch);
270 /* Get the VID and PID of a device specified by path. */
271 static int ser_hid_hidapi_get_vid_pid(const char *path,
272 uint16_t *vid, uint16_t *pid)
276 * Bummer! It would have been most reliable to just open the
277 * device by the specified path, and grab its VID:PID. But
278 * there is no way to get these parameters, neither in the
279 * HIDAPI itself, nor when cheating and reaching behind the API
280 * and accessing the libusb handle in dirty ways. :(
286 dev = hid_open_path(path);
290 *vid = dev->vendor_id;
292 *pid = dev->product_id;
298 * The fallback approach. Enumerate all devices, compare the
299 * enumerated USB path, and grab the VID:PID. Unfortunately the
300 * caller can provide path specs that differ from enumerated
301 * paths yet mean the same (address the same device). This needs
302 * more attention. Though the specific format of the path and
303 * its meaning are said to be OS specific, which is why we may
304 * not assume anything about it...
308 struct hid_device_info *devs, *dev;
311 usbpath = g_strdup(path);
312 hidpath = extract_hidapi_path(usbpath);
318 devs = hid_enumerate(0x0000, 0x0000);
320 for (dev = devs; dev; dev = dev->next) {
321 if (strcmp(dev->path, hidpath) != 0)
324 *vid = dev->vendor_id;
326 *pid = dev->product_id;
330 hid_free_enumeration(devs);
333 return found ? SR_OK : SR_ERR_NA;
337 static int ser_hid_hidapi_open_dev(struct sr_serial_dev_inst *serial)
341 if (!serial->usb_path || !*serial->usb_path)
345 * A path is available, assume that either a GUI or a
346 * user has copied what a previous listing has provided.
347 * Or a scan determined a matching device's USB path.
349 if (!serial->hid_path)
350 serial->hid_path = extract_hidapi_path(serial->usb_path);
351 hid_dev = hid_open_path(serial->hid_path);
353 serial->hid_path = NULL;
357 serial->hid_dev = hid_dev;
358 hid_set_nonblocking(hid_dev, 1);
363 static void ser_hid_hidapi_close_dev(struct sr_serial_dev_inst *serial)
365 if (serial->hid_dev) {
366 hid_close(serial->hid_dev);
367 serial->hid_dev = NULL;
368 serial->hid_path = NULL;
370 g_slist_free_full(serial->hid_source_args, g_free);
371 serial->hid_source_args = NULL;
374 struct hidapi_source_args_t {
375 /* Application callback. */
376 sr_receive_data_callback cb;
378 /* The serial device, to store RX data. */
379 struct sr_serial_dev_inst *serial;
383 * Gets periodically invoked by the glib main loop. "Drives" (checks)
384 * progress of USB communication, and invokes the application's callback
385 * which processes RX data (when some has become available), as well as
386 * handles application level timeouts.
388 static int hidapi_source_cb(int fd, int revents, void *cb_data)
390 struct hidapi_source_args_t *args;
391 uint8_t rx_buf[SER_HID_CHUNK_SIZE];
397 * Drain receive data which the chip might have pending. This is
398 * "a copy" of the "background part" of ser_hid_read(), without
399 * the timeout support code, and not knowing how much data the
400 * application is expecting.
403 rc = args->serial->hid_chip_funcs->read_bytes(args->serial,
404 rx_buf, sizeof(rx_buf), 0);
406 ser_hid_mask_databits(args->serial, rx_buf, rc);
407 sr_ser_queue_rx_data(args->serial, rx_buf, rc);
412 * When RX data became available (now or earlier), pass this
413 * condition to the application callback. Always periodically
414 * run the application callback, since it handles timeouts and
415 * might carry out other tasks as well like signalling progress.
417 if (sr_ser_has_queued_data(args->serial))
419 rc = args->cb(fd, revents, args->cb_data);
424 #define WITH_MAXIMUM_TIMEOUT_VALUE 10
425 static int ser_hid_hidapi_setup_source_add(struct sr_session *session,
426 struct sr_serial_dev_inst *serial, int events, int timeout,
427 sr_receive_data_callback cb, void *cb_data)
429 struct hidapi_source_args_t *args;
434 /* Optionally enforce a minimum poll period. */
435 if (WITH_MAXIMUM_TIMEOUT_VALUE && timeout > WITH_MAXIMUM_TIMEOUT_VALUE)
436 timeout = WITH_MAXIMUM_TIMEOUT_VALUE;
438 /* Allocate status container for background data reception. */
439 args = g_malloc0(sizeof(*args));
441 args->cb_data = cb_data;
442 args->serial = serial;
445 * Have a periodic timer installed. Register the allocated block
446 * with the serial device, since the GSource's finalizer won't
447 * free the memory, and we haven't bothered to create a custom
448 * HIDAPI specific GSource.
450 rc = sr_session_source_add(session, -1, events, timeout,
451 hidapi_source_cb, args);
456 serial->hid_source_args = g_slist_append(serial->hid_source_args, args);
461 static int ser_hid_hidapi_setup_source_remove(struct sr_session *session,
462 struct sr_serial_dev_inst *serial)
466 (void)sr_session_source_remove(session, -1);
468 * Release callback args here already? Can there be more than
469 * one source registered at any time, given that we pass fd -1
470 * which is used as the key for the session?
476 SR_PRIV int ser_hid_hidapi_get_report(struct sr_serial_dev_inst *serial,
477 uint8_t *data, size_t len)
481 rc = hid_get_feature_report(serial->hid_dev, data, len);
488 SR_PRIV int ser_hid_hidapi_set_report(struct sr_serial_dev_inst *serial,
489 const uint8_t *data, size_t len)
492 const wchar_t *err_text;
494 rc = hid_send_feature_report(serial->hid_dev, data, len);
496 err_text = hid_error(serial->hid_dev);
497 sr_dbg("%s() hidapi error: %ls", __func__, err_text);
504 SR_PRIV int ser_hid_hidapi_get_data(struct sr_serial_dev_inst *serial,
505 uint8_t ep, uint8_t *data, size_t len, int timeout)
512 rc = hid_read_timeout(serial->hid_dev, data, len, timeout);
514 rc = hid_read(serial->hid_dev, data, len);
523 SR_PRIV int ser_hid_hidapi_set_data(struct sr_serial_dev_inst *serial,
524 uint8_t ep, const uint8_t *data, size_t len, int timeout)
531 rc = hid_write(serial->hid_dev, data, len);
539 /* {{{ support for serial-over-HID chips */
541 static struct ser_hid_chip_functions **chips[SER_HID_CHIP_LAST] = {
542 [SER_HID_CHIP_UNKNOWN] = NULL,
543 [SER_HID_CHIP_BTC_BU86X] = &ser_hid_chip_funcs_bu86x,
544 [SER_HID_CHIP_SIL_CP2110] = &ser_hid_chip_funcs_cp2110,
545 [SER_HID_CHIP_VICTOR_DMM] = &ser_hid_chip_funcs_victor,
546 [SER_HID_CHIP_WCH_CH9325] = &ser_hid_chip_funcs_ch9325,
549 static struct ser_hid_chip_functions *get_hid_chip_funcs(enum ser_hid_chip_t chip)
551 struct ser_hid_chip_functions *funcs;
553 if (chip >= ARRAY_SIZE(chips))
557 funcs = *chips[chip];
564 static int ser_hid_setup_funcs(struct sr_serial_dev_inst *serial)
570 if (serial->hid_chip && !serial->hid_chip_funcs) {
571 serial->hid_chip_funcs = get_hid_chip_funcs(serial->hid_chip);
572 if (!serial->hid_chip_funcs)
580 * Takes a pointer to the chip spec with potentially trailing data,
581 * returns the chip index and advances the spec pointer upon match,
582 * returns SER_HID_CHIP_UNKNOWN upon mismatch.
584 static enum ser_hid_chip_t ser_hid_chip_find_enum(const char **spec_p)
587 enum ser_hid_chip_t idx;
588 struct ser_hid_chip_functions *desc;
590 if (!spec_p || !*spec_p)
591 return SER_HID_CHIP_UNKNOWN;
594 return SER_HID_CHIP_UNKNOWN;
595 for (idx = 0; idx < SER_HID_CHIP_LAST; idx++) {
596 desc = get_hid_chip_funcs(idx);
601 if (!g_str_has_prefix(spec, desc->chipname))
603 spec += strlen(desc->chipname);
608 return SER_HID_CHIP_UNKNOWN;
611 /* See if we can find a chip name for a VID:PID spec. */
612 SR_PRIV const char *ser_hid_chip_find_name_vid_pid(uint16_t vid, uint16_t pid)
615 struct ser_hid_chip_functions *desc;
616 const struct vid_pid_item *vid_pids;
618 for (chip_idx = 0; chip_idx < SER_HID_CHIP_LAST; chip_idx++) {
619 desc = get_hid_chip_funcs(chip_idx);
624 vid_pids = desc->vid_pid_items;
627 while (vid_pids->vid) {
628 if (vid_pids->vid == vid && vid_pids->pid == pid)
629 return desc->chipname;
638 * See if a text string is a valid USB path for a HID device.
639 * @param[in] serial The serial port that is about to get opened.
640 * @param[in] path The (assumed) USB path specification.
641 * @return SR_OK upon success, SR_ERR* upon failure.
643 static int try_open_path(struct sr_serial_dev_inst *serial, const char *path)
647 serial->usb_path = g_strdup(path);
648 rc = ser_hid_hidapi_open_dev(serial);
649 ser_hid_hidapi_close_dev(serial);
650 g_free(serial->usb_path);
651 serial->usb_path = NULL;
657 * Parse conn= specs for serial over HID communication.
659 * @param[in] serial The serial port that is about to get opened.
660 * @param[in] spec The caller provided conn= specification.
661 * @param[out] chip_ref Pointer to a chip type (enum).
662 * @param[out] path_ref Pointer to a USB path (text string).
663 * @param[out] serno_ref Pointer to a serial number (text string).
665 * @return 0 upon success, non-zero upon failure. Fills the *_ref output
670 * Summary of parsing rules as they are implemented:
671 * - Insist on the "hid" prefix. Accept "hid" alone without any other
673 * - The first field that follows can be a chip spec, yet is optional.
674 * - Any other field is assumed to be either a USB path or a serial
675 * number. There is no point in specifying both of these, as either
676 * of them uniquely identifies a device.
678 * Supported formats resulting from these rules:
680 * hid[/<chip>]/usb=<bus>.<dev>[.<if>]
681 * hid[/<chip>]/raw=<path> (may contain slashes!)
682 * hid[/<chip>]/sn=serno
684 * This routine just parses the conn= spec, which either was provided by
685 * a user, or may reflect (cite) an item of a previously gathered listing
686 * (clipboard provided by CLI clients, or selected from a GUI form).
687 * Another routine will fill in the blanks, and do the cable selection
688 * when a filter was specified.
690 * Users will want to use short forms when they need to come up with the
691 * specs by themselves. The "verbose" or seemingly redundant forms (chip
692 * _and_ path/serno spec) are useful when the cable uses non-standard or
693 * not-yet-supported VID:PID items when automatic chip detection fails.
695 static int ser_hid_parse_conn_spec(
696 struct sr_serial_dev_inst *serial, const char *spec,
697 enum ser_hid_chip_t *chip_ref, char **path_ref, char **serno_ref)
700 enum ser_hid_chip_t chip;
705 *chip_ref = SER_HID_CHIP_UNKNOWN;
710 chip = SER_HID_CHIP_UNKNOWN;
713 if (!serial || !spec || !*spec)
717 /* The "hid" prefix is mandatory. */
718 if (!g_str_has_prefix(p, SER_HID_CONN_PREFIX))
720 p += strlen(SER_HID_CONN_PREFIX);
723 * Check for prefixed fields, assume chip type spec otherwise.
724 * Paths and serial numbers "are greedy" (span to the end of
725 * the input spec). Chip types are optional, and cannot repeat
733 if (g_str_has_prefix(p, SER_HID_USB_PREFIX)) {
734 rc = try_open_path(serial, p);
739 } else if (g_str_has_prefix(p, SER_HID_RAW_PREFIX)) {
740 rc = try_open_path(serial, p);
745 } else if (g_str_has_prefix(p, SER_HID_SNR_PREFIX)) {
746 p += strlen(SER_HID_SNR_PREFIX);
754 chip = ser_hid_chip_find_enum(&endptr);
762 sr_err("unsupported conn= spec %s, error at %s", spec, p);
773 if (path_ref && path)
775 if (serno_ref && serno)
781 /* Get and compare serial number. Boolean return value. */
782 static int check_serno(const char *path, const char *serno_want)
785 const char *hid_path;
789 usb_path = g_strdup(path);
790 hid_path = extract_hidapi_path(usb_path);
791 rc = ser_hid_hidapi_get_serno(hid_path, serno_got, sizeof(serno_got));
794 sr_dbg("DBG: %s(), could not get serial number", __func__);
798 return strcmp(serno_got, serno_want) == 0;
801 static GSList *append_find(GSList *devs, const char *path)
808 copy = g_strdup(path);
809 devs = g_slist_append(devs, copy);
814 static GSList *list_paths_for_vids_pids(const struct vid_pid_item *vid_pids)
821 for (idx = 0; /* EMPTY */; idx++) {
824 } else if (!vid_pids[idx].vid) {
827 vid = vid_pids[idx].vid;
828 pid = vid_pids[idx].pid;
830 list = ser_hid_hidapi_find_usb(list, append_find, vid, pid);
839 * Search for a matching USB device for HID communication.
841 * @param[inout] chip The HID chip type (enum).
842 * @param[inout] usbpath The USB path for the device (string).
843 * @param[in] serno The serial number to search for.
845 * @retval SR_OK upon success
846 * @retval SR_ERR_* upon failure.
850 * This routine fills in blanks which the conn= spec parser left open.
851 * When not specified yet, the HID chip type gets determined. When a
852 * serial number was specified, then search the corresponding device.
853 * Upon completion, the chip type and USB path for the device shall be
854 * known, as these are essential for subsequent operation.
856 static int ser_hid_chip_search(enum ser_hid_chip_t *chip_ref,
857 char **path_ref, const char *serno)
859 enum ser_hid_chip_t chip;
861 int have_chip, have_path, have_serno;
862 struct ser_hid_chip_functions *chip_funcs;
867 const struct vid_pid_item *vid_pids;
868 GSList *list, *matched, *matched2, *tmplist;
878 * Simplify the more complex conditions somewhat by assigning
879 * to local variables. Handle the easiest conditions first.
880 * - Either path or serial number can be specified, but not both
882 * - When a USB path is given, immediately see which HID chip
883 * the device has, without the need for enumeration.
884 * - When a serial number is given, enumerate the devices and
885 * search for that number. Either enumerate all devices of the
886 * specified HID chip type (try the VID:PID pairs that we are
887 * aware of), or try all HID devices for unknown chip types.
888 * Not finding the serial number is fatal.
889 * - When no path was found yet, enumerate the devices and pick
890 * one of them. Try known VID:PID pairs for a HID chip, or all
891 * devices for unknown chips. Make sure to pick a device of a
892 * supported chip type if the chip was not specified.
893 * - Determine the chip type if not yet known. There should be
894 * a USB path by now, determined in one of the above blocks.
896 have_chip = (chip != SER_HID_CHIP_UNKNOWN) ? 1 : 0;
897 have_path = (path && *path) ? 1 : 0;
898 have_serno = (serno && *serno) ? 1 : 0;
899 if (have_path && have_serno) {
900 sr_err("Unsupported combination of USB path and serno");
903 chip_funcs = have_chip ? get_hid_chip_funcs(chip) : NULL;
904 if (have_chip && !chip_funcs)
906 if (have_chip && !chip_funcs->vid_pid_items)
908 if (have_path && !have_chip) {
910 rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
913 name = ser_hid_chip_find_name_vid_pid(vid, pid);
916 chip = ser_hid_chip_find_enum(&name);
917 if (chip == SER_HID_CHIP_UNKNOWN)
922 vid_pids = have_chip ? chip_funcs->vid_pid_items : NULL;
923 list = list_paths_for_vids_pids(vid_pids);
927 for (tmplist = list; tmplist; tmplist = tmplist->next) {
928 path = get_hidapi_path_copy(tmplist->data);
929 serno_matched = check_serno(path, serno);
938 path = g_strdup(matched->data);
940 g_slist_free_full(list, g_free);
943 vid_pids = have_chip ? chip_funcs->vid_pid_items : NULL;
944 list = list_paths_for_vids_pids(vid_pids);
947 matched = matched2 = NULL;
949 /* List already only contains specified chip. */
951 matched2 = list->next;
953 /* Works for lists with one or multiple chips. Saves indentation. */
954 for (tmplist = list; tmplist; tmplist = tmplist->next) {
957 path = tmplist->data;
958 rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
959 if (rc || !ser_hid_chip_find_name_vid_pid(vid, pid))
971 g_slist_free_full(list, g_free);
975 * TODO Optionally fail harder, expect users to provide
976 * unambiguous cable specs.
979 sr_info("More than one cable matches, random pick.");
980 path = get_hidapi_path_copy(matched->data);
982 g_slist_free_full(list, g_free);
984 if (have_path && !have_chip) {
986 rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
989 name = ser_hid_chip_find_name_vid_pid(vid, pid);
992 chip = ser_hid_chip_find_enum(&name);
993 if (chip == SER_HID_CHIP_UNKNOWN)
1007 /* {{{ transport methods called by the common serial.c code */
1009 /* See if a serial port's name refers to an HID type. */
1010 SR_PRIV int ser_name_is_hid(struct sr_serial_dev_inst *serial)
1017 if (!serial->port || !*serial->port)
1020 /* Accept either "hid" alone, or "hid/" as a prefix. */
1021 if (!g_str_has_prefix(serial->port, SER_HID_CONN_PREFIX))
1023 off = strlen(SER_HID_CONN_PREFIX);
1024 sep = serial->port[off];
1025 if (sep != '\0' && sep != '/')
1031 static int ser_hid_open(struct sr_serial_dev_inst *serial, int flags)
1033 enum ser_hid_chip_t chip;
1034 char *usbpath, *serno;
1039 if (ser_hid_setup_funcs(serial) != 0) {
1040 sr_err("Cannot determine HID communication library.");
1044 rc = ser_hid_parse_conn_spec(serial, serial->port,
1045 &chip, &usbpath, &serno);
1050 * When a serial number was specified, or when the chip type or
1051 * the USB path were not specified, do a search to determine the
1052 * device's USB path.
1054 if (!chip || !usbpath || serno) {
1055 rc = ser_hid_chip_search(&chip, &usbpath, serno);
1061 * Open the HID device. Only store chip type and device handle
1062 * when open completes successfully.
1064 serial->hid_chip = chip;
1065 if (ser_hid_setup_funcs(serial) != 0) {
1066 sr_err("Cannot determine HID chip specific routines.");
1069 if (usbpath && *usbpath)
1070 serial->usb_path = usbpath;
1071 if (serno && *serno)
1072 serial->usb_serno = serno;
1074 rc = ser_hid_hidapi_open_dev(serial);
1076 sr_err("Failed to open HID device.");
1077 serial->hid_chip = 0;
1078 g_free(serial->usb_path);
1079 serial->usb_path = NULL;
1080 g_free(serial->usb_serno);
1081 serial->usb_serno = NULL;
1085 if (!serial->rcv_buffer)
1086 serial->rcv_buffer = g_string_sized_new(SER_HID_CHUNK_SIZE);
1091 static int ser_hid_close(struct sr_serial_dev_inst *serial)
1093 ser_hid_hidapi_close_dev(serial);
1098 static int ser_hid_set_params(struct sr_serial_dev_inst *serial,
1099 int baudrate, int bits, int parity, int stopbits,
1100 int flowcontrol, int rts, int dtr)
1102 if (ser_hid_setup_funcs(serial) != 0)
1104 if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->set_params)
1107 return serial->hid_chip_funcs->set_params(serial,
1108 baudrate, bits, parity, stopbits,
1109 flowcontrol, rts, dtr);
1112 static int ser_hid_setup_source_add(struct sr_session *session,
1113 struct sr_serial_dev_inst *serial, int events, int timeout,
1114 sr_receive_data_callback cb, void *cb_data)
1116 return ser_hid_hidapi_setup_source_add(session, serial,
1117 events, timeout, cb, cb_data);
1120 static int ser_hid_setup_source_remove(struct sr_session *session,
1121 struct sr_serial_dev_inst *serial)
1123 return ser_hid_hidapi_setup_source_remove(session, serial);
1126 static GSList *ser_hid_list(GSList *list, sr_ser_list_append_t append)
1128 return ser_hid_hidapi_list(list, append);
1131 static GSList *ser_hid_find_usb(GSList *list, sr_ser_find_append_t append,
1132 uint16_t vendor_id, uint16_t product_id)
1134 return ser_hid_hidapi_find_usb(list, append, vendor_id, product_id);
1137 static int ser_hid_flush(struct sr_serial_dev_inst *serial)
1139 if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->flush)
1142 return serial->hid_chip_funcs->flush(serial);
1145 static int ser_hid_drain(struct sr_serial_dev_inst *serial)
1147 if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->drain)
1150 return serial->hid_chip_funcs->drain(serial);
1153 static int ser_hid_write(struct sr_serial_dev_inst *serial,
1154 const void *buf, size_t count,
1155 int nonblocking, unsigned int timeout_ms)
1157 int total, max_chunk, chunk_len;
1160 if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->write_bytes)
1162 if (!serial->hid_chip_funcs->max_bytes_per_request)
1166 max_chunk = serial->hid_chip_funcs->max_bytes_per_request;
1169 if (max_chunk && chunk_len > max_chunk)
1170 chunk_len = max_chunk;
1171 rc = serial->hid_chip_funcs->write_bytes(serial, buf, chunk_len);
1173 sr_err("Error sending transmit data to HID device.");
1176 if (rc != chunk_len) {
1177 sr_warn("Short transmission to HID device (%d/%d bytes)?",
1185 * Need we wait here? For data to drain through the slow
1186 * UART. Not all UART-over-HID chips will have FIFOs.
1197 static int ser_hid_read(struct sr_serial_dev_inst *serial,
1198 void *buf, size_t count,
1199 int nonblocking, unsigned int timeout_ms)
1201 gint64 deadline_us, now_us;
1202 uint8_t buffer[SER_HID_CHUNK_SIZE];
1206 if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->read_bytes)
1208 if (!serial->hid_chip_funcs->max_bytes_per_request)
1212 * Immediately satisfy the caller's request from the RX buffer
1213 * if the requested amount of data is available already.
1215 if (sr_ser_has_queued_data(serial) >= count)
1216 return sr_ser_unqueue_rx_data(serial, buf, count);
1219 * When a timeout was specified, then determine the deadline
1220 * where to stop reception.
1223 now_us = 0; /* Silence a (false) compiler warning. */
1225 now_us = g_get_monotonic_time();
1226 deadline_us = now_us + timeout_ms * 1000;
1230 * Keep receiving from the port until the caller's requested
1231 * amount of data has become available, or the timeout has
1232 * expired. In the absence of a timeout, stop reading when an
1233 * attempt no longer yields receive data.
1235 * This implementation assumes that applications will call the
1236 * read routine often enough, or that reception continues in
1237 * background, such that data is not lost and hardware and
1238 * software buffers won't overrun.
1242 * Determine the timeout (in milliseconds) for this
1243 * iteration. The 'now_us' timestamp was initially
1244 * determined above, and gets updated at the bottom of
1248 timeout_ms = (deadline_us - now_us) / 1000;
1251 } else if (nonblocking) {
1258 * Check the HID transport for the availability of more
1261 rc = serial->hid_chip_funcs->read_bytes(serial,
1262 buffer, sizeof(buffer), timeout_ms);
1264 sr_dbg("DBG: %s() read error %d.", __func__, rc);
1268 ser_hid_mask_databits(serial, buffer, rc);
1269 sr_ser_queue_rx_data(serial, buffer, rc);
1271 got = sr_ser_has_queued_data(serial);
1274 * Stop reading when the requested amount is available,
1275 * or when the timeout has expired.
1277 * TODO Consider whether grabbing all RX data is more
1278 * desirable. Implementing this approach requires a cheap
1279 * check for the availability of more data on the USB level.
1283 if (nonblocking && !rc)
1286 now_us = g_get_monotonic_time();
1287 if (now_us >= deadline_us) {
1288 sr_dbg("DBG: %s() read loop timeout.", __func__);
1295 * Satisfy the caller's demand for receive data from previously
1296 * queued incoming data.
1301 return sr_ser_unqueue_rx_data(serial, buf, count);
1304 static struct ser_lib_functions serlib_hid = {
1305 .open = ser_hid_open,
1306 .close = ser_hid_close,
1307 .flush = ser_hid_flush,
1308 .drain = ser_hid_drain,
1309 .write = ser_hid_write,
1310 .read = ser_hid_read,
1311 .set_params = ser_hid_set_params,
1312 .setup_source_add = ser_hid_setup_source_add,
1313 .setup_source_remove = ser_hid_setup_source_remove,
1314 .list = ser_hid_list,
1315 .find_usb = ser_hid_find_usb,
1316 .get_frame_format = NULL,
1318 SR_PRIV struct ser_lib_functions *ser_lib_funcs_hid = &serlib_hid;
1323 SR_PRIV int ser_name_is_hid(struct sr_serial_dev_inst *serial)
1330 SR_PRIV struct ser_lib_functions *ser_lib_funcs_hid = NULL;