*/
#include "config.h"
+#include <glib.h>
+#ifdef HAVE_LIBHIDAPI
+#include <hidapi.h>
+#endif
#include <libsigrok/libsigrok.h>
#include "libsigrok-internal.h"
+#include "serial_hid.h"
+#include <stdlib.h>
+#include <string.h>
+#ifdef G_OS_WIN32
+#include <windows.h> /* for HANDLE */
+#endif
/** @cond PRIVATE */
#define LOG_PREFIX "serial-hid"
/** @endcond */
+#ifdef HAVE_SERIAL_COMM
+
+/**
+ * @file
+ *
+ * Serial port handling, HIDAPI library specific support code.
+ */
+
+/**
+ * @defgroup grp_serial_hid Serial port handling, HID group
+ *
+ * Make serial-over-HID communication appear like a regular serial port.
+ *
+ * @{
+ */
+
+#ifdef HAVE_LIBHIDAPI
+/* {{{ helper routines */
+
+/* Strip off parity bits for "odd" data bit counts like in 7e1 frames. */
+static void ser_hid_mask_databits(struct sr_serial_dev_inst *serial,
+ uint8_t *data, size_t len)
+{
+ uint32_t mask32;
+ uint8_t mask;
+ size_t idx;
+
+ if ((serial->comm_params.data_bits % 8) == 0)
+ return;
+
+ mask32 = (1UL << serial->comm_params.data_bits) - 1;
+ mask = mask32 & 0xff;
+ for (idx = 0; idx < len; idx++)
+ data[idx] &= mask;
+}
+
+/* }}} */
+/* {{{ open/close/list/find HIDAPI connection, exchange HID requests and data */
+
+/*
+ * Convert a HIDAPI path (which depends on the target platform, and may
+ * depend on one of several available API variants on that platform) to
+ * something that is usable as a "port name" in conn= specs.
+ *
+ * Since conn= is passed with -d where multiple options (among them conn=)
+ * are separated by colons, port names themselves cannot contain colons.
+ *
+ * Just replace colons by a period in the simple case (Linux platform,
+ * hidapi-libusb implementation, bus/address/interface). Prefix the
+ * HIDAPI path in the complex cases (Linux hidapi-hidraw, Windows, Mac).
+ * Paths with colons outside of libusb based implementations are unhandled
+ * here, but were not yet seen on any sigrok supported platform either.
+ * So just reject them.
+ */
+static char *get_hidapi_path_copy(const char *path)
+{
+ static const char *accept = "0123456789abcdefABCDEF:";
+ static const char *keep = "0123456789abcdefABCDEF";
+
+ int has_colon;
+ int is_hex_colon;
+ char *name;
+
+ has_colon = strchr(path, ':') != NULL;
+ is_hex_colon = strspn(path, accept) == strlen(path);
+ if (has_colon && !is_hex_colon) {
+ sr_err("Unsupported HIDAPI path format: %s", path);
+ return NULL;
+ }
+ if (is_hex_colon) {
+ name = g_strdup_printf("%s%s", SER_HID_USB_PREFIX, path);
+ g_strcanon(name + strlen(SER_HID_USB_PREFIX), keep, '.');
+ } else {
+ name = g_strdup_printf("%s%s", SER_HID_RAW_PREFIX, path);
+ }
+
+ return name;
+}
+
+/*
+ * Undo the port name construction that was done during scan. Extract
+ * the HIDAPI path from a conn= input spec (the part after the hid/
+ * prefix and chip type).
+ *
+ * Strip off the "raw" prefix, or undo colon substitution. See @ref
+ * get_hidapi_path_copy() for details.
+ */
+static const char *extract_hidapi_path(char *buffer)
+{
+ static const char *keep = "0123456789abcdefABCDEF:";
+
+ const char *p;
+
+ p = buffer;
+ if (!p || !*p)
+ return NULL;
+
+ if (strncmp(p, SER_HID_RAW_PREFIX, strlen(SER_HID_RAW_PREFIX)) == 0) {
+ p += strlen(SER_HID_RAW_PREFIX);
+ return p;
+ }
+ if (strncmp(p, SER_HID_USB_PREFIX, strlen(SER_HID_USB_PREFIX)) == 0) {
+ p += strlen(SER_HID_USB_PREFIX);
+ g_strcanon(buffer, keep, ':');
+ return p;
+ }
+
+ return NULL;
+}
+
+/*
+ * The HIDAPI specific list() callback, invoked by common serial.c code.
+ * Enumerate all devices (no VID:PID is involved).
+ * Invoke an 'append' callback with "path" and "name".
+ */
+static GSList *ser_hid_hidapi_list(GSList *list, sr_ser_list_append_t append)
+{
+ struct hid_device_info *devs, *curdev;
+ const char *chipname;
+ char *path, *name;
+ wchar_t *manuf, *prod, *serno;
+ uint16_t vid, pid;
+ GString *desc;
+
+ devs = hid_enumerate(0x0000, 0x0000);
+ for (curdev = devs; curdev; curdev = curdev->next) {
+ /*
+ * Determine the chip name from VID:PID (if it's one of
+ * the supported types with an ID known to us).
+ */
+ vid = curdev->vendor_id;
+ pid = curdev->product_id;
+ sr_dbg("DIAG: hidapi enum, vid:pid %04x:%04x, path %s\n",
+ curdev->vendor_id, curdev->product_id, curdev->path);
+ chipname = ser_hid_chip_find_name_vid_pid(vid, pid);
+ if (!chipname)
+ chipname = "<chip>";
+
+ /*
+ * Prefix port names such that open() calls with this
+ * conn= spec will end up here and contain all details
+ * that are essential for processing.
+ */
+ path = get_hidapi_path_copy(curdev->path);
+ if (!path)
+ continue;
+ name = g_strdup_printf("%s/%s/%s",
+ SER_HID_CONN_PREFIX, chipname, path);
+ g_free(path);
+
+ /*
+ * Print whatever information was available. Construct
+ * the description text from pieces. Absence of fields
+ * is not fatal, we have seen perfectly usable cables
+ * that only had a VID and PID (permissions were not an
+ * issue).
+ */
+ manuf = curdev->manufacturer_string;
+ prod = curdev->product_string;
+ serno = curdev->serial_number;
+ vid = curdev->vendor_id;
+ pid = curdev->product_id;
+ desc = g_string_sized_new(128);
+ g_string_append_printf(desc, "HID");
+ if (manuf)
+ g_string_append_printf(desc, " %ls", manuf);
+ if (prod)
+ g_string_append_printf(desc, " %ls", prod);
+ if (serno)
+ g_string_append_printf(desc, " %ls", serno);
+ if (vid && pid)
+ g_string_append_printf(desc, " %04hx:%04hx", vid, pid);
+ list = append(list, name, desc->str);
+ g_string_free(desc, TRUE);
+ g_free(name);
+ }
+ hid_free_enumeration(devs);
+
+ return list;
+}
+
+/*
+ * The HIDAPI specific find_usb() callback, invoked by common serial.c code.
+ * Enumerate devices for the specified VID:PID pair.
+ * Invoke an "append" callback with 'path' for the device.
+ */
+static GSList *ser_hid_hidapi_find_usb(GSList *list, sr_ser_find_append_t append,
+ uint16_t vendor_id, uint16_t product_id)
+{
+ struct hid_device_info *devs, *curdev;
+ const char *name;
+
+ devs = hid_enumerate(vendor_id, product_id);
+ for (curdev = devs; curdev; curdev = curdev->next) {
+ name = curdev->path;
+ list = append(list, name);
+ }
+ hid_free_enumeration(devs);
+
+ return list;
+}
+
+/* Get the serial number of a device specified by path. */
+static int ser_hid_hidapi_get_serno(const char *path, char *buf, size_t blen)
+{
+ char *usbpath;
+ const char *hidpath;
+ hid_device *dev;
+ wchar_t *serno_wch;
+ int rc;
+
+ if (!path || !*path)
+ return SR_ERR_ARG;
+ usbpath = g_strdup(path);
+ hidpath = extract_hidapi_path(usbpath);
+ dev = hidpath ? hid_open_path(hidpath) : NULL;
+ g_free(usbpath);
+ if (!dev)
+ return SR_ERR_IO;
+
+ serno_wch = g_malloc0(blen * sizeof(*serno_wch));
+ rc = hid_get_serial_number_string(dev, serno_wch, blen - 1);
+ hid_close(dev);
+ if (rc != 0) {
+ g_free(serno_wch);
+ return SR_ERR_IO;
+ }
+
+ snprintf(buf, blen, "%ls", serno_wch);
+ g_free(serno_wch);
+
+ return SR_OK;
+}
+
+/* Get the VID and PID of a device specified by path. */
+static int ser_hid_hidapi_get_vid_pid(const char *path,
+ uint16_t *vid, uint16_t *pid)
+{
+#if 0
+ /*
+ * Bummer! It would have been most reliable to just open the
+ * device by the specified path, and grab its VID:PID. But
+ * there is no way to get these parameters, neither in the
+ * HIDAPI itself, nor when cheating and reaching behind the API
+ * and accessing the libusb handle in dirty ways. :(
+ */
+ hid_device *dev;
+
+ if (!path || !*path)
+ return SR_ERR_ARG;
+ dev = hid_open_path(path);
+ if (!dev)
+ return SR_ERR_IO;
+ if (vid)
+ *vid = dev->vendor_id;
+ if (pid)
+ *pid = dev->product_id;
+ hid_close(dev);
+
+ return SR_OK;
+#else
+ /*
+ * The fallback approach. Enumerate all devices, compare the
+ * enumerated USB path, and grab the VID:PID. Unfortunately the
+ * caller can provide path specs that differ from enumerated
+ * paths yet mean the same (address the same device). This needs
+ * more attention. Though the specific format of the path and
+ * its meaning are said to be OS specific, which is why we may
+ * not assume anything about it...
+ */
+ char *usbpath;
+ const char *hidpath;
+ struct hid_device_info *devs, *dev;
+ int found;
+
+ usbpath = g_strdup(path);
+ hidpath = extract_hidapi_path(usbpath);
+ if (!hidpath) {
+ g_free(usbpath);
+ return SR_ERR_NA;
+ }
+
+ devs = hid_enumerate(0x0000, 0x0000);
+ found = 0;
+ for (dev = devs; dev; dev = dev->next) {
+ if (strcmp(dev->path, hidpath) != 0)
+ continue;
+ if (vid)
+ *vid = dev->vendor_id;
+ if (pid)
+ *pid = dev->product_id;
+ found = 1;
+ break;
+ }
+ hid_free_enumeration(devs);
+ g_free(usbpath);
+
+ return found ? SR_OK : SR_ERR_NA;
+#endif
+}
+
+static int ser_hid_hidapi_open_dev(struct sr_serial_dev_inst *serial)
+{
+ hid_device *hid_dev;
+
+ if (!serial->usb_path || !*serial->usb_path)
+ return SR_ERR_ARG;
+
+ /*
+ * A path is available, assume that either a GUI or a
+ * user has copied what a previous listing has provided.
+ * Or a scan determined a matching device's USB path.
+ */
+ if (!serial->hid_path)
+ serial->hid_path = extract_hidapi_path(serial->usb_path);
+ hid_dev = hid_open_path(serial->hid_path);
+ sr_dbg("DBG: %s(), hid_open_path(\"%s\") => %p", __func__,
+ serial->hid_path, hid_dev);
+ if (!hid_dev) {
+ serial->hid_path = NULL;
+ return SR_ERR_IO;
+ }
+
+ serial->hid_dev = hid_dev;
+ hid_set_nonblocking(hid_dev, 1);
+
+ return SR_OK;
+}
+
+static void ser_hid_hidapi_close_dev(struct sr_serial_dev_inst *serial)
+{
+ if (serial->hid_dev) {
+ hid_close(serial->hid_dev);
+ serial->hid_dev = NULL;
+ serial->hid_path = NULL;
+ }
+ g_slist_free_full(serial->hid_source_args, g_free);
+ serial->hid_source_args = NULL;
+}
+
+struct hidapi_source_args_t {
+ /* Application callback. */
+ sr_receive_data_callback cb;
+ void *cb_data;
+ /* The serial device, to store RX data. */
+ struct sr_serial_dev_inst *serial;
+};
+
+/*
+ * Gets periodically invoked by the glib main loop. "Drives" (checks)
+ * progress of USB communication, and invokes the application's callback
+ * which processes RX data (when some has become available), as well as
+ * handles application level timeouts.
+ */
+static int hidapi_source_cb(int fd, int revents, void *cb_data)
+{
+ struct hidapi_source_args_t *args;
+ uint8_t rx_buf[SER_HID_CHUNK_SIZE];
+ int rc;
+
+ sr_dbg("DBG: %s() fd %d, evt 0x%x, data %p.", __func__, fd, revents, cb_data);
+ args = cb_data;
+
+ /*
+ * Drain receive data which the chip might have pending. This is
+ * "a copy" of the "background part" of ser_hid_read(), without
+ * the timeout support code, and not knowing how much data the
+ * application is expecting.
+ */
+ do {
+ rc = args->serial->hid_chip_funcs->read_bytes(args->serial,
+ rx_buf, sizeof(rx_buf), 0);
+ if (rc > 0) {
+ sr_dbg("DBG: %s() queueing %d bytes.", __func__, rc);
+ ser_hid_mask_databits(args->serial, rx_buf, rc);
+ sr_ser_queue_rx_data(args->serial, rx_buf, rc);
+ }
+ } while (rc > 0);
+
+ /*
+ * When RX data became available (now or earlier), pass this
+ * condition to the application callback. Always periodically
+ * run the application callback, since it handles timeouts and
+ * might carry out other tasks as well like signalling progress.
+ */
+ if (sr_ser_has_queued_data(args->serial))
+ revents |= G_IO_IN;
+ rc = args->cb(fd, revents, args->cb_data);
+ sr_dbg("DBG: %s() rc %d.", __func__, rc);
+
+ return rc;
+}
+
+#define WITH_MAXIMUM_TIMEOUT_VALUE 10
+static int ser_hid_hidapi_setup_source_add(struct sr_session *session,
+ struct sr_serial_dev_inst *serial, int events, int timeout,
+ sr_receive_data_callback cb, void *cb_data)
+{
+ struct hidapi_source_args_t *args;
+ int rc;
+
+ sr_dbg("DBG: %s() evt 0x%x, to %d.", __func__, events, timeout);
+ (void)events;
+
+ /* Optionally enforce a minimum poll period. */
+ if (WITH_MAXIMUM_TIMEOUT_VALUE && timeout > WITH_MAXIMUM_TIMEOUT_VALUE)
+ timeout = WITH_MAXIMUM_TIMEOUT_VALUE;
+
+ /* Allocate status container for background data reception. */
+ args = g_malloc0(sizeof(*args));
+ args->cb = cb;
+ args->cb_data = cb_data;
+ args->serial = serial;
+
+ /*
+ * Have a periodic timer installed. Register the allocated block
+ * with the serial device, since the GSource's finalizer won't
+ * free the memory, and we haven't bothered to create a custom
+ * HIDAPI specific GSource.
+ */
+ rc = sr_session_source_add(session, -1, events, timeout,
+ hidapi_source_cb, args);
+ sr_dbg("DBG: %s() added, rc %d.", __func__, rc);
+ if (rc != SR_OK) {
+ g_free(args);
+ return rc;
+ }
+ serial->hid_source_args = g_slist_append(serial->hid_source_args, args);
+
+ return SR_OK;
+}
+
+static int ser_hid_hidapi_setup_source_remove(struct sr_session *session,
+ struct sr_serial_dev_inst *serial)
+{
+ (void)serial;
+
+ sr_dbg("DBG: %s().", __func__);
+ (void)sr_session_source_remove(session, -1);
+ /*
+ * Release callback args here already? Can there be more than
+ * one source registered at any time, given that we pass fd -1
+ * which is used as the key for the session?
+ */
+
+ return SR_OK;
+}
+
+SR_PRIV int ser_hid_hidapi_get_report(struct sr_serial_dev_inst *serial,
+ uint8_t *data, size_t len)
+{
+ int rc;
+
+ rc = hid_get_feature_report(serial->hid_dev, data, len);
+ if (rc < 0)
+ return SR_ERR_IO;
+
+ return rc;
+}
+
+SR_PRIV int ser_hid_hidapi_set_report(struct sr_serial_dev_inst *serial,
+ const uint8_t *data, size_t len)
+{
+ int rc;
+ const wchar_t *err_text;
+
+ rc = hid_send_feature_report(serial->hid_dev, data, len);
+ if (rc < 0) {
+ err_text = hid_error(serial->hid_dev);
+ sr_dbg("%s() hidapi error: %ls", __func__, err_text);
+ return SR_ERR_IO;
+ }
+
+ return rc;
+}
+
+SR_PRIV int ser_hid_hidapi_get_data(struct sr_serial_dev_inst *serial,
+ uint8_t ep, uint8_t *data, size_t len, int timeout)
+{
+ int rc;
+
+ (void)ep;
+
+ if (timeout)
+ rc = hid_read_timeout(serial->hid_dev, data, len, timeout);
+ else
+ rc = hid_read(serial->hid_dev, data, len);
+ if (rc < 0)
+ return SR_ERR_IO;
+ if (rc == 0)
+ return 0;
+
+ return rc;
+}
+
+SR_PRIV int ser_hid_hidapi_set_data(struct sr_serial_dev_inst *serial,
+ uint8_t ep, const uint8_t *data, size_t len, int timeout)
+{
+ int rc;
+
+ (void)ep;
+ (void)timeout;
+
+ rc = hid_write(serial->hid_dev, data, len);
+ if (rc < 0)
+ return SR_ERR_IO;
+
+ return rc;
+}
+
+/* }}} */
+/* {{{ support for serial-over-HID chips */
+
+static struct ser_hid_chip_functions **chips[SER_HID_CHIP_LAST] = {
+ [SER_HID_CHIP_UNKNOWN] = NULL,
+};
+
+static struct ser_hid_chip_functions *get_hid_chip_funcs(enum ser_hid_chip_t chip)
+{
+ struct ser_hid_chip_functions *funcs;
+
+ if (chip >= ARRAY_SIZE(chips))
+ return NULL;
+ if (!chips[chip])
+ return NULL;
+ funcs = *chips[chip];
+ if (!funcs)
+ return NULL;
+
+ return funcs;
+}
+
+static int ser_hid_setup_funcs(struct sr_serial_dev_inst *serial)
+{
+
+ if (!serial)
+ return -1;
+
+ if (serial->hid_chip && !serial->hid_chip_funcs) {
+ serial->hid_chip_funcs = get_hid_chip_funcs(serial->hid_chip);
+ if (!serial->hid_chip_funcs)
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Takes a pointer to the chip spec with potentially trailing data,
+ * returns the chip index and advances the spec pointer upon match,
+ * returns SER_HID_CHIP_UNKNOWN upon mismatch.
+ */
+static enum ser_hid_chip_t ser_hid_chip_find_enum(char **spec_p)
+{
+ gchar *spec;
+ enum ser_hid_chip_t idx;
+ struct ser_hid_chip_functions *desc;
+
+ if (!spec_p || !*spec_p)
+ return SER_HID_CHIP_UNKNOWN;
+ spec = *spec_p;
+ if (!*spec)
+ return SER_HID_CHIP_UNKNOWN;
+ for (idx = 0; idx < SER_HID_CHIP_LAST; idx++) {
+ desc = get_hid_chip_funcs(idx);
+ if (!desc)
+ continue;
+ if (!desc->chipname)
+ continue;
+ if (!g_str_has_prefix(spec, desc->chipname))
+ continue;
+ spec += strlen(desc->chipname);
+ *spec_p = spec;
+ return idx;
+ }
+
+ return SER_HID_CHIP_UNKNOWN;
+}
+
+/* See if we can find a chip name for a VID:PID spec. */
+SR_PRIV const char *ser_hid_chip_find_name_vid_pid(uint16_t vid, uint16_t pid)
+{
+ size_t chip_idx;
+ struct ser_hid_chip_functions *desc;
+ const struct vid_pid_item *vid_pids;
+
+ for (chip_idx = 0; chip_idx < SER_HID_CHIP_LAST; chip_idx++) {
+ desc = get_hid_chip_funcs(chip_idx);
+ if (!desc)
+ continue;
+ if (!desc->chipname)
+ continue;
+ vid_pids = desc->vid_pid_items;
+ if (!vid_pids)
+ continue;
+ while (vid_pids->vid) {
+ if (vid_pids->vid == vid && vid_pids->pid == pid) {
+ return desc->chipname;
+ }
+ vid_pids++;
+ }
+ }
+
+ return NULL;
+}
+
+static const char *ser_hid_chip_get_text(enum ser_hid_chip_t idx)
+{
+ struct ser_hid_chip_functions *desc;
+
+ desc = get_hid_chip_funcs(idx);
+ if (!desc)
+ return NULL;
+
+ return desc->chipdesc;
+}
+
+/**
+ * See if a text string is a valid USB path for a HID device.
+ * @param[in] serial The serial port that is about to get opened.
+ * @param[in] path The (assumed) USB path specification.
+ * @return SR_OK upon success, SR_ERR* upon failure.
+ */
+static int try_open_path(struct sr_serial_dev_inst *serial, const char *path)
+{
+ int rc;
+
+ serial->usb_path = g_strdup(path);
+ rc = ser_hid_hidapi_open_dev(serial);
+ ser_hid_hidapi_close_dev(serial);
+ g_free(serial->usb_path);
+ serial->usb_path = NULL;
+
+ return rc;
+}
+
+/**
+ * Parse conn= specs for serial over HID communication.
+ *
+ * @param[in] serial The serial port that is about to get opened.
+ * @param[in] spec The caller provided conn= specification.
+ * @param[out] chip_ref Pointer to a chip type (enum).
+ * @param[out] path_ref Pointer to a USB path (text string).
+ * @param[out] serno_ref Pointer to a serial number (text string).
+ *
+ * @return 0 upon success, non-zero upon failure. Fills the *_ref output
+ * values.
+ *
+ * @internal
+ *
+ * Summary of parsing rules as they are implemented:
+ * - Insist on the "hid" prefix. Accept "hid" alone without any other
+ * additional field.
+ * - The first field that follows can be a chip spec, yet is optional.
+ * - Any other field is assumed to be either a USB path or a serial
+ * number. There is no point in specifying both of these, as either
+ * of them uniquely identifies a device.
+ *
+ * Supported formats resulting from these rules:
+ * hid[/<chip>]
+ * hid[/<chip>]/usb=<bus>.<dev>[.<if>]
+ * hid[/<chip>]/raw=<path> (may contain slashes!)
+ * hid[/<chip>]/sn=serno
+ *
+ * This routine just parses the conn= spec, which either was provided by
+ * a user, or may reflect (cite) an item of a previously gathered listing
+ * (clipboard provided by CLI clients, or selected from a GUI form).
+ * Another routine will fill in the blanks, and do the cable selection
+ * when a filter was specified.
+ *
+ * Users will want to use short forms when they need to come up with the
+ * specs by themselves. The "verbose" or seemingly redundant forms (chip
+ * _and_ path/serno spec) are useful when the cable uses non-standard or
+ * not-yet-supported VID:PID items when automatic chip detection fails.
+ */
+static int ser_hid_parse_conn_spec(
+ struct sr_serial_dev_inst *serial, const char *spec,
+ enum ser_hid_chip_t *chip_ref, char **path_ref, char **serno_ref)
+{
+ const char *p;
+ enum ser_hid_chip_t chip;
+ char *path, *serno;
+ int rc;
+
+ if (chip_ref)
+ *chip_ref = SER_HID_CHIP_UNKNOWN;
+ if (path_ref)
+ *path_ref = NULL;
+ if (serno_ref)
+ *serno_ref = NULL;
+ chip = SER_HID_CHIP_UNKNOWN;
+ path = serno = NULL;
+
+ if (!serial || !spec || !*spec)
+ return SR_ERR_ARG;
+ sr_dbg("DBG: %s(), input spec: %s", __func__, spec);
+ p = spec;
+
+ /* The "hid" prefix is mandatory. */
+ if (!g_str_has_prefix(p, SER_HID_CONN_PREFIX)) {
+ sr_dbg("DBG: %s(), not a HID port", __func__);
+ return SR_ERR_ARG;
+ }
+ p += strlen(SER_HID_CONN_PREFIX);
+
+ /*
+ * Check for prefixed fields, assume chip type spec otherwise.
+ * Paths and serial numbers "are greedy" (span to the end of
+ * the input spec). Chip types are optional, and cannot repeat
+ * multiple times.
+ */
+ while (*p) {
+ if (*p == '/')
+ p++;
+ if (!*p)
+ break;
+ if (g_str_has_prefix(p, SER_HID_USB_PREFIX)) {
+ rc = try_open_path(serial, p);
+ sr_dbg("DBG: %s(), open usb path %s => rc %d", __func__, p, rc);
+ if (rc != SR_OK)
+ return rc;
+ path = g_strdup(p);
+ p += strlen(p);
+ } else if (g_str_has_prefix(p, SER_HID_RAW_PREFIX)) {
+ rc = try_open_path(serial, p);
+ sr_dbg("DBG: %s(), open raw path %s => rc %d", __func__, p, rc);
+ if (rc != SR_OK)
+ return rc;
+ path = g_strdup(p);
+ p += strlen(p);
+ } else if (g_str_has_prefix(p, SER_HID_SNR_PREFIX)) {
+ p += strlen(SER_HID_SNR_PREFIX);
+ sr_dbg("DBG: %s(), snr %s", __func__, p);
+ serno = g_strdup(p);
+ p += strlen(p);
+ } else if (!chip) {
+ char *copy, *endptr;
+ const char *name;
+ copy = g_strdup(p);
+ endptr = copy;
+ chip = ser_hid_chip_find_enum(&endptr);
+ sr_dbg("DBG: %s(), chip search, %s => %u", __func__, p, chip);
+ if (!chip) {
+ g_free(copy);
+ return SR_ERR_ARG;
+ }
+ p += endptr - copy;
+ g_free(copy);
+ name = ser_hid_chip_get_text(chip);
+ sr_dbg("DBG: %s(), chip %s", __func__, name);
+ } else {
+ sr_err("unsupported conn= spec %s, error at %s", spec, p);
+ return SR_ERR_ARG;
+ }
+ if (*p == '/')
+ p++;
+ if (path || serno)
+ break;
+ }
+
+ sr_dbg("DBG: %s() done, chip %d, path %s, serno %s", __func__, chip, path, serno);
+ if (chip_ref)
+ *chip_ref = chip;
+ if (path_ref && path)
+ *path_ref = path;
+ if (serno_ref && serno)
+ *serno_ref = serno;
+
+ return SR_OK;
+}
+
+/* Get and compare serial number. Boolean return value. */
+static int check_serno(const char *path, const char *serno_want)
+{
+ char *usb_path;
+ const char *hid_path;
+ char serno_got[128];
+ int rc;
+
+ sr_dbg("DBG: %s(\"%s\", \"%s\")", __func__, path, serno_want);
+
+ usb_path = g_strdup(path);
+ hid_path = extract_hidapi_path(usb_path);
+ rc = ser_hid_hidapi_get_serno(hid_path, serno_got, sizeof(serno_got));
+ sr_dbg("DBG: %s(), usb %s, hidapi %s => rc %d", __func__, usb_path, hid_path, rc);
+ g_free(usb_path);
+ if (rc) {
+ sr_dbg("DBG: %s(), could not get serial number", __func__);
+ return 0;
+ }
+ sr_dbg("DBG: %s(), got serno \"%s\"", __func__, serno_got);
+
+ rc = strcmp(serno_got, serno_want) == 0;
+ sr_dbg("DBG: %s(), return %d", __func__, rc);
+
+ return rc;
+}
+
+static GSList *append_find(GSList *devs, const char *path)
+{
+ char *copy;
+
+ if (!path || !*path)
+ return devs;
+
+ copy = g_strdup(path);
+ devs = g_slist_append(devs, copy);
+
+ return devs;
+}
+
+static GSList *list_paths_for_vids_pids(const struct vid_pid_item *vid_pids)
+{
+ GSList *list;
+ size_t idx;
+ uint16_t vid, pid;
+
+ list = NULL;
+ for (idx = 0; /* EMPTY */; idx++) {
+ if (!vid_pids) {
+ vid = pid = 0;
+ } else if (!vid_pids[idx].vid) {
+ break;
+ } else {
+ vid = vid_pids[idx].vid;
+ pid = vid_pids[idx].pid;
+ }
+ sr_dbg("DBG: %s(), searching VID:PID %04hx:%04hx",
+ __func__, vid, pid);
+ list = ser_hid_hidapi_find_usb(list, append_find, vid, pid);
+ if (!vid_pids)
+ break;
+ }
+
+ return list;
+}
+
+/**
+ * Search for a matching USB device for HID communication.
+ *
+ * @param[inout] chip The HID chip type (enum).
+ * @param[inout] usbpath The USB path for the device (string).
+ * @param[in] serno The serial number to search for.
+ *
+ * @retval SR_OK upon success
+ * @retval SR_ERR_* upon failure.
+ *
+ * @internal
+ *
+ * This routine fills in blanks which the conn= spec parser left open.
+ * When not specified yet, the HID chip type gets determined. When a
+ * serial number was specified, then search the corresponding device.
+ * Upon completion, the chip type and USB path for the device shall be
+ * known, as these are essential for subsequent operation.
+ */
+static int ser_hid_chip_search(enum ser_hid_chip_t *chip_ref,
+ char **path_ref, const char *serno)
+{
+ enum ser_hid_chip_t chip;
+ char *path;
+ int have_chip, have_path, have_serno;
+ struct ser_hid_chip_functions *chip_funcs;
+ int rc;
+ int serno_matched;
+ uint16_t vid, pid;
+ const char *name;
+ const struct vid_pid_item *vid_pids;
+ GSList *list, *matched, *matched2, *tmplist;
+
+ if (!chip_ref)
+ return SR_ERR_ARG;
+ chip = *chip_ref;
+ if (!path_ref)
+ return SR_ERR_ARG;
+ path = *path_ref;
+ sr_dbg("DBG: %s() enter, chip %d, path %s, serno %s", __func__,
+ chip, path, serno ? serno : "<none>");
+
+ /*
+ * Simplify the more complex conditions somewhat by assigning
+ * to local variables. Handle the easiest conditions first.
+ * - Either path or serial number can be specified, but not both
+ * at the same time.
+ * - When a USB path is given, immediately see which HID chip
+ * the device has, without the need for enumeration.
+ * - When a serial number is given, enumerate the devices and
+ * search for that number. Either enumerate all devices of the
+ * specified HID chip type (try the VID:PID pairs that we are
+ * aware of), or try all HID devices for unknown chip types.
+ * Not finding the serial number is fatal.
+ * - When no path was found yet, enumerate the devices and pick
+ * one of them. Try known VID:PID pairs for a HID chip, or all
+ * devices for unknown chips. Make sure to pick a device of a
+ * supported chip type if the chip was not specified.
+ * - Determine the chip type if not yet known. There should be
+ * a USB path by now, determined in one of the above blocks.
+ */
+ have_chip = (chip != SER_HID_CHIP_UNKNOWN) ? 1 : 0;
+ have_path = (path && *path) ? 1 : 0;
+ have_serno = (serno && *serno) ? 1 : 0;
+ sr_dbg("DBG: %s(), have chip %d, path %d, serno %d", __func__,
+ have_chip, have_path, have_serno);
+ if (have_path && have_serno) {
+ sr_err("Unsupported combination of USB path and serno");
+ return SR_ERR_ARG;
+ }
+ chip_funcs = have_chip ? get_hid_chip_funcs(chip) : NULL;
+ if (have_chip && !chip_funcs)
+ return SR_ERR_NA;
+ if (have_chip && !chip_funcs->vid_pid_items)
+ return SR_ERR_NA;
+ if (have_path && !have_chip) {
+ sr_dbg("DBG: %s(), searching chip for path %s", __func__, path);
+ vid = pid = 0;
+ rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
+ sr_dbg("DBG: %s(), rc %d, VID:PID %04x:%04x", __func__, rc, vid, pid);
+ if (rc != SR_OK)
+ return rc;
+ name = ser_hid_chip_find_name_vid_pid(vid, pid);
+ sr_dbg("DBG: %s(), name %s", __func__, name);
+ if (!name || !*name)
+ return SR_ERR_NA;
+ chip = ser_hid_chip_find_enum((char **)&name);
+ sr_dbg("DBG: %s(), chip %d", __func__, chip);
+ if (chip == SER_HID_CHIP_UNKNOWN)
+ return SR_ERR_NA;
+ have_chip = 1;
+ }
+ if (have_serno) {
+ sr_dbg("DBG: %s(), searching path for serno %s", __func__, serno);
+ vid_pids = have_chip ? chip_funcs->vid_pid_items : NULL;
+ list = list_paths_for_vids_pids(vid_pids);
+ sr_dbg("DBG: %s(), vid/pid list for chip type %p", __func__, list);
+ if (!list)
+ return SR_ERR_NA;
+ matched = NULL;
+ for (tmplist = list; tmplist; tmplist = tmplist->next) {
+ path = get_hidapi_path_copy(tmplist->data);
+ sr_dbg("DBG: %s(), checking %s", __func__, path);
+ serno_matched = check_serno(path, serno);
+ g_free(path);
+ if (!serno_matched)
+ continue;
+ matched = tmplist;
+ break;
+ }
+ if (!matched)
+ return SR_ERR_NA;
+ path = g_strdup(matched->data);
+ sr_dbg("DBG: %s(), match, path %s", __func__, path);
+ have_path = 1;
+ g_slist_free_full(list, g_free);
+ }
+ if (!have_path) {
+ sr_dbg("DBG: %s(), searching path, chip %d", __func__, chip);
+ vid_pids = have_chip ? chip_funcs->vid_pid_items : NULL;
+ list = list_paths_for_vids_pids(vid_pids);
+ if (!list)
+ return SR_ERR_NA;
+ for (tmplist = list; tmplist; tmplist = tmplist->next) {
+ path = tmplist->data;
+ sr_dbg("DBG: %s(), path %s", __func__, path);
+ }
+ matched = matched2 = NULL;
+ if (have_chip) {
+ /* List already only contains specified chip. */
+ matched = list;
+ path = matched->data;
+ sr_dbg("DBG: %s(), match 1 %s", __func__, path);
+ matched2 = list->next;
+ if (matched2) {
+ path = matched2->data;
+ sr_dbg("DBG: %s(), match 2 %s", __func__, path);
+ }
+ }
+ /* Works for lists with one or multiple chips. Saves indentation. */
+ for (tmplist = list; tmplist; tmplist = tmplist->next) {
+ if (have_chip)
+ break;
+ path = tmplist->data;
+ rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
+ if (rc || !ser_hid_chip_find_name_vid_pid(vid, pid))
+ continue;
+ if (!matched) {
+ matched = tmplist;
+ sr_dbg("DBG: %s(), match 1 %s", __func__, path);
+ continue;
+ }
+ if (!matched2) {
+ matched2 = tmplist;
+ sr_dbg("DBG: %s(), match 2 %s", __func__, path);
+ break;
+ }
+ }
+ if (!matched) {
+ g_slist_free_full(list, g_free);
+ return SR_ERR_NA;
+ }
+ /*
+ * TODO Optionally fail harder, expect users to provide
+ * unambiguous cable specs.
+ */
+ if (matched2)
+ sr_info("More than one cable matches, random pick.");
+ path = get_hidapi_path_copy(matched->data);
+ sr_dbg("DBG: %s(), match, path %s", __func__, path);
+ have_path = 1;
+ g_slist_free_full(list, g_free);
+ }
+ if (have_path && !have_chip) {
+ sr_dbg("DBG: %s(), searching chip for path %s", __func__, path);
+ vid = pid = 0;
+ rc = ser_hid_hidapi_get_vid_pid(path, &vid, &pid);
+ sr_dbg("DBG: %s(), rc %d, VID:PID %04x:%04x", __func__, rc, vid, pid);
+ if (rc != SR_OK)
+ return rc;
+ name = ser_hid_chip_find_name_vid_pid(vid, pid);
+ sr_dbg("DBG: %s(), name %s", __func__, name);
+ if (!name || !*name)
+ return SR_ERR_NA;
+ chip = ser_hid_chip_find_enum((char **)&name);
+ sr_dbg("DBG: %s(), chip %d", __func__, chip);
+ if (chip == SER_HID_CHIP_UNKNOWN)
+ return SR_ERR_NA;
+ have_chip = 1;
+ }
+
+ sr_dbg("DBG: %s() leave, chip %d, path %s", __func__, chip, path);
+ if (chip_ref)
+ *chip_ref = chip;
+ if (path_ref)
+ *path_ref = path;
+
+ return SR_OK;
+}
+
+/* }}} */
+/* {{{ transport methods called by the common serial.c code */
+
+/* See if a serial port's name refers to an HID type. */
+SR_PRIV int ser_name_is_hid(struct sr_serial_dev_inst *serial)
+{
+ size_t off;
+ char sep;
+
+ if (!serial)
+ return 0;
+ if (!serial->port || !*serial->port)
+ return 0;
+
+ /* Accept either "hid" alone, or "hid/" as a prefix. */
+ if (!g_str_has_prefix(serial->port, SER_HID_CONN_PREFIX))
+ return 0;
+ off = strlen(SER_HID_CONN_PREFIX);
+ sep = serial->port[off];
+ if (sep != '\0' && sep != '/')
+ return 0;
+
+ return 1;
+}
+
+static int ser_hid_open(struct sr_serial_dev_inst *serial, int flags)
+{
+ enum ser_hid_chip_t chip;
+ char *usbpath, *serno;
+ int rc;
+
+ (void)flags;
+
+ if (ser_hid_setup_funcs(serial) != 0) {
+ sr_err("Cannot determine HID communication library.");
+ return SR_ERR_NA;
+ }
+
+ rc = ser_hid_parse_conn_spec(serial, serial->port,
+ &chip, &usbpath, &serno);
+ if (rc != SR_OK)
+ return SR_ERR_ARG;
+
+ /*
+ * When a serial number was specified, or when the chip type or
+ * the USB path were not specified, do a search to determine the
+ * device's USB path.
+ */
+ if (!chip || !usbpath || serno) {
+ sr_dbg("DBG: %s(), searching ...", __func__);
+ rc = ser_hid_chip_search(&chip, &usbpath, serno);
+ if (rc != 0)
+ return SR_ERR_NA;
+ }
+
+ /*
+ * Open the HID device. Only store chip type and device handle
+ * when open completes successfully.
+ */
+ serial->hid_chip = chip;
+ if (ser_hid_setup_funcs(serial) != 0) {
+ sr_err("Cannot determine HID chip specific routines.");
+ return SR_ERR_NA;
+ }
+ if (usbpath && *usbpath)
+ serial->usb_path = usbpath;
+ if (serno && *serno)
+ serial->usb_serno = serno;
+
+ rc = ser_hid_hidapi_open_dev(serial);
+ if (rc) {
+ sr_err("Failed to open HID device.");
+ serial->hid_chip = 0;
+ g_free(serial->usb_path);
+ serial->usb_path = NULL;
+ g_free(serial->usb_serno);
+ serial->usb_serno = NULL;
+ return SR_ERR_IO;
+ }
+ sr_dbg("DBG: %s() done, OK", __func__);
+
+ if (!serial->rcv_buffer)
+ serial->rcv_buffer = g_string_sized_new(SER_HID_CHUNK_SIZE);
+
+ return SR_OK;
+}
+
+static int ser_hid_close(struct sr_serial_dev_inst *serial)
+{
+ sr_dbg("DBG: %s()", __func__);
+ ser_hid_hidapi_close_dev(serial);
+
+ return SR_OK;
+}
+
+static int ser_hid_set_params(struct sr_serial_dev_inst *serial,
+ int baudrate, int bits, int parity, int stopbits,
+ int flowcontrol, int rts, int dtr)
+{
+ int rc;
+
+ sr_dbg("DBG: %s() enter", __func__);
+ if (ser_hid_setup_funcs(serial) != 0)
+ return SR_ERR_NA;
+ sr_dbg("DBG: %s() chip funcs set", __func__);
+ if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->set_params)
+ return SR_ERR_NA;
+ sr_dbg("DBG: %s() set params avail", __func__);
+ rc = serial->hid_chip_funcs->set_params(serial,
+ baudrate, bits, parity, stopbits,
+ flowcontrol, rts, dtr);
+ sr_dbg("DBG: %s() set params rc %d", __func__, rc);
+
+ return rc;
+}
+
+static int ser_hid_setup_source_add(struct sr_session *session,
+ struct sr_serial_dev_inst *serial, int events, int timeout,
+ sr_receive_data_callback cb, void *cb_data)
+{
+ return ser_hid_hidapi_setup_source_add(session, serial,
+ events, timeout, cb, cb_data);
+}
+
+static int ser_hid_setup_source_remove(struct sr_session *session,
+ struct sr_serial_dev_inst *serial)
+{
+ return ser_hid_hidapi_setup_source_remove(session, serial);
+}
+
+static GSList *ser_hid_list(GSList *list, sr_ser_list_append_t append)
+{
+ return ser_hid_hidapi_list(list, append);
+}
+
+static GSList *ser_hid_find_usb(GSList *list, sr_ser_find_append_t append,
+ uint16_t vendor_id, uint16_t product_id)
+{
+ return ser_hid_hidapi_find_usb(list, append, vendor_id, product_id);
+}
+
+static int ser_hid_flush(struct sr_serial_dev_inst *serial)
+{
+ if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->flush)
+ return SR_ERR_NA;
+
+ return serial->hid_chip_funcs->flush(serial);
+}
+
+static int ser_hid_drain(struct sr_serial_dev_inst *serial)
+{
+ if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->drain)
+ return SR_ERR_NA;
+
+ return serial->hid_chip_funcs->drain(serial);
+}
+
+static int ser_hid_write(struct sr_serial_dev_inst *serial,
+ const void *buf, size_t count,
+ int nonblocking, unsigned int timeout_ms)
+{
+ int total, max_chunk, chunk_len;
+ int rc;
+
+ if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->write_bytes)
+ return SR_ERR_NA;
+ if (!serial->hid_chip_funcs->max_bytes_per_request)
+ return SR_ERR_NA;
+
+ sr_dbg("DBG: %s() shall send %zu bytes TX data.", __func__, count);
+ total = 0;
+ max_chunk = serial->hid_chip_funcs->max_bytes_per_request;
+ while (count > 0) {
+ chunk_len = count;
+ if (max_chunk && chunk_len > max_chunk)
+ chunk_len = max_chunk;
+ rc = serial->hid_chip_funcs->write_bytes(serial, buf, chunk_len);
+ if (rc < 0) {
+ sr_err("Error sending transmit data to HID device.");
+ return total;
+ }
+ if (rc != chunk_len) {
+ sr_warn("Short transmission to HID device (%d/%d bytes)?",
+ rc, chunk_len);
+ return total;
+ }
+ buf += chunk_len;
+ count -= chunk_len;
+ total += chunk_len;
+ /* TODO
+ * Need we wait here? For data to drain through the slow
+ * UART. Not all UART-over-HID chips will have FIFOs.
+ */
+ if (!nonblocking) {
+ (void)timeout_ms;
+ /* TODO */
+ }
+ }
+
+ return total;
+}
+
+static int ser_hid_read(struct sr_serial_dev_inst *serial,
+ void *buf, size_t count,
+ int nonblocking, unsigned int timeout_ms)
+{
+ gint64 deadline_us, now_us;
+ uint8_t buffer[SER_HID_CHUNK_SIZE];
+ int rc;
+ unsigned int got;
+
+ sr_dbg("DBG: %s() count %zd, block %d, to %u", __func__,
+ count, !nonblocking, timeout_ms);
+
+ if (!serial->hid_chip_funcs || !serial->hid_chip_funcs->read_bytes)
+ return SR_ERR_NA;
+ if (!serial->hid_chip_funcs->max_bytes_per_request)
+ return SR_ERR_NA;
+
+ /*
+ * Immediately satisfy the caller's request from the RX buffer
+ * if the requested amount of data is available already.
+ */
+ if (sr_ser_has_queued_data(serial) >= count) {
+ rc = sr_ser_unqueue_rx_data(serial, buf, count);
+ return rc;
+ }
+
+ /*
+ * When a timeout was specified, then determine the deadline
+ * where to stop reception.
+ */
+ deadline_us = 0;
+ now_us = 0; /* Silence a (false) compiler warning. */
+ if (timeout_ms) {
+ now_us = g_get_monotonic_time();
+ deadline_us = now_us + timeout_ms * 1000;
+ }
+
+ /*
+ * Keep receiving from the port until the caller's requested
+ * amount of data has become available, or the timeout has
+ * expired. In the absence of a timeout, stop reading when an
+ * attempt no longer yields receive data.
+ *
+ * This implementation assumes that applications will call the
+ * read routine often enough, or that reception continues in
+ * background, such that data is not lost and hardware and
+ * software buffers won't overrun.
+ */
+ while (TRUE) {
+ /*
+ * Determine the timeout (in milliseconds) for this
+ * iteration. The 'now_us' timestamp was initially
+ * determined above, and gets updated at the bottom of
+ * the loop.
+ */
+ if (deadline_us) {
+ timeout_ms = (deadline_us - now_us) / 1000;
+ if (!timeout_ms)
+ timeout_ms = 1;
+ } else if (nonblocking) {
+ timeout_ms = 10;
+ } else {
+ timeout_ms = 0;
+ }
+
+ /*
+ * Check the HID transport for the availability of more
+ * receive data.
+ */
+ rc = serial->hid_chip_funcs->read_bytes(serial,
+ buffer, sizeof(buffer), timeout_ms);
+ if (rc < 0) {
+ sr_dbg("DBG: %s() read error %d.", __func__, rc);
+ return SR_ERR;
+ }
+ if (rc) {
+ sr_dbg("DBG: %s() queueing %d bytes.", __func__, rc);
+ ser_hid_mask_databits(serial, buffer, rc);
+ sr_ser_queue_rx_data(serial, buffer, rc);
+ }
+ got = sr_ser_has_queued_data(serial);
+
+ /*
+ * Stop reading when the requested amount is available,
+ * or when the timeout has expired.
+ *
+ * TODO Consider whether grabbing all RX data is more
+ * desirable. Implementing this approach requires a cheap
+ * check for the availability of more data on the USB level.
+ */
+ if (got >= count)
+ break;
+ if (nonblocking && !rc)
+ break;
+ if (deadline_us) {
+ now_us = g_get_monotonic_time();
+ if (now_us >= deadline_us) {
+ sr_dbg("DBG: %s() read loop timeout.", __func__);
+ break;
+ }
+ }
+ }
+
+ /*
+ * Satisfy the caller's demand for receive data from previously
+ * queued incoming data.
+ */
+ if (got > count)
+ got = count;
+ sr_dbg("DBG: %s() passing %d bytes.", __func__, got);
+ rc = sr_ser_unqueue_rx_data(serial, buf, count);
+
+ return rc;
+}
+
+static struct ser_lib_functions serlib_hid = {
+ .open = ser_hid_open,
+ .close = ser_hid_close,
+ .flush = ser_hid_flush,
+ .drain = ser_hid_drain,
+ .write = ser_hid_write,
+ .read = ser_hid_read,
+ .set_params = ser_hid_set_params,
+ .setup_source_add = ser_hid_setup_source_add,
+ .setup_source_remove = ser_hid_setup_source_remove,
+ .list = ser_hid_list,
+ .find_usb = ser_hid_find_usb,
+ .get_frame_format = NULL,
+};
+SR_PRIV struct ser_lib_functions *ser_lib_funcs_hid = &serlib_hid;
+
+/* }}} */
+#else
+
SR_PRIV int ser_name_is_hid(struct sr_serial_dev_inst *serial)
{
(void)serial;
}
SR_PRIV struct ser_lib_functions *ser_lib_funcs_hid = NULL;
+
+#endif
+#endif
+/** @} */