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-rw-r--r--configfs.c846
1 files changed, 0 insertions, 846 deletions
diff --git a/configfs.c b/configfs.c
deleted file mode 100644
index 1dfde95..0000000
--- a/configfs.c
+++ /dev/null
@@ -1,846 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-/*
- * ConfigFS Gadget device handling
- *
- * Copyright (C) 2018 Kieran Bingham
- *
- * Contact: Kieran Bingham <kieran.bingham@ideasonboard.com>
- */
-
-/* To provide basename and asprintf from the GNU library. */
- #define _GNU_SOURCE
-
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <glob.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include <linux/videodev2.h>
-
-#include "configfs.h"
-#include "tools.h"
-
-/* -----------------------------------------------------------------------------
- * Path handling and support
- */
-
-static char *path_join(const char *dirname, const char *name)
-{
- char *path;
-
- asprintf(&path, "%s/%s", dirname, name);
-
- return path;
-}
-
-static char *path_glob_first_match(const char *g)
-{
- glob_t globbuf;
- char *match = NULL;
-
- glob(g, 0, NULL, &globbuf);
-
- if (globbuf.gl_pathc)
- match = strdup(globbuf.gl_pathv[0]);
-
- globfree(&globbuf);
-
- return match;
-}
-
-/*
- * Find and return the full path of the first directory entry that satisfies
- * the match function.
- */
-static char *dir_first_match(const char *dir, int(*match)(const struct dirent *))
-{
- struct dirent **entries;
- unsigned int i;
- int n_entries;
- char *path;
-
- n_entries = scandir(dir, &entries, match, alphasort);
- if (n_entries < 0)
- return NULL;
-
- if (n_entries == 0) {
- free(entries);
- return NULL;
- }
-
- path = path_join(dir, entries[0]->d_name);
-
- for (i = 0; i < (unsigned int)n_entries; ++i)
- free(entries[i]);
-
- free(entries);
-
- return path;
-}
-
-/* -----------------------------------------------------------------------------
- * Attribute handling
- */
-
-static int attribute_read(const char *path, const char *file, void *buf,
- unsigned int len)
-{
- char *f;
- int ret;
- int fd;
-
- f = path_join(path, file);
- if (!f)
- return -ENOMEM;
-
- fd = open(f, O_RDONLY);
- free(f);
- if (fd == -1) {
- printf("Failed to open attribute %s: %s\n", file,
- strerror(errno));
- return -ENOENT;
- }
-
- ret = read(fd, buf, len);
- close(fd);
-
- if (ret < 0) {
- printf("Failed to read attribute %s: %s\n", file,
- strerror(errno));
- return -ENODATA;
- }
-
- return len;
-}
-
-static int attribute_read_uint(const char *path, const char *file,
- unsigned int *val)
-{
- /* 4,294,967,295 */
- char buf[11];
- char *endptr;
- int ret;
-
- ret = attribute_read(path, file, buf, sizeof(buf) - 1);
- if (ret < 0)
- return ret;
-
- buf[ret] = '\0';
-
- errno = 0;
-
- /* base 0: Autodetect hex, octal, decimal. */
- *val = strtoul(buf, &endptr, 0);
- if (errno)
- return -errno;
-
- if (endptr == buf)
- return -ENODATA;
-
- return 0;
-}
-
-static char *attribute_read_str(const char *path, const char *file)
-{
- char buf[1024];
- char *p;
- int ret;
-
- ret = attribute_read(path, file, buf, sizeof(buf) - 1);
- if (ret < 0)
- return NULL;
-
- buf[ret] = '\0';
-
- p = strrchr(buf, '\n');
- if (p != buf)
- *p = '\0';
-
- return strdup(buf);
-}
-
-/* -----------------------------------------------------------------------------
- * UDC parsing
- */
-
-/*
- * udc_find_video_device - Find the video device node for a UVC function
- * @udc: The UDC name
- * @function: The UVC function name
- *
- * This function finds the video device node corresponding to a UVC function as
- * specified by a @function name and @udc name.
- *
- * The @function parameter specifies the name of the USB function, usually in
- * the form "uvc.%u". If NULL the first function found will be used.
- *
- * The @udc parameter specifies the name of the UDC. If NULL any UDC that
- * contains a function matching the @function name will be used.
- *
- * Return a pointer to a newly allocated string containing the video device node
- * full path if the function is found. Otherwise return NULL. The returned
- * pointer must be freed by the caller with a call to free().
- */
-static char *udc_find_video_device(const char *udc, const char *function)
-{
- char *vpath;
- char *video = NULL;
- glob_t globbuf;
- unsigned int i;
-
- asprintf(&vpath, "/sys/class/udc/%s/device/gadget/video4linux/video*",
- udc ? udc : "*");
- if (!vpath)
- return NULL;
-
- glob(vpath, 0, NULL, &globbuf);
- free(vpath);
-
- for (i = 0; i < globbuf.gl_pathc; ++i) {
- char *config;
- bool match;
-
- /* Match on the first if no search string. */
- if (!function)
- break;
-
- config = attribute_read_str(globbuf.gl_pathv[i],
- "function_name");
- match = strcmp(function, config) == 0;
-
- free(config);
-
- if (match)
- break;
- }
-
- if (i < globbuf.gl_pathc) {
- const char *v = basename(globbuf.gl_pathv[i]);
-
- video = path_join("/dev", v);
- }
-
- globfree(&globbuf);
-
- return video;
-}
-
-/* ------------------------------------------------------------------------
- * GUIDs and formats
- */
-
-#define UVC_GUID_FORMAT_MJPEG \
- { 'M', 'J', 'P', 'G', 0x00, 0x00, 0x10, 0x00, \
- 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
-#define UVC_GUID_FORMAT_YUY2 \
- { 'Y', 'U', 'Y', '2', 0x00, 0x00, 0x10, 0x00, \
- 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
-
-struct uvc_function_format_info {
- uint8_t guid[16];
- uint32_t fcc;
-};
-
-static struct uvc_function_format_info uvc_formats[] = {
- {
- .guid = UVC_GUID_FORMAT_YUY2,
- .fcc = V4L2_PIX_FMT_YUYV,
- },
- {
- .guid = UVC_GUID_FORMAT_MJPEG,
- .fcc = V4L2_PIX_FMT_MJPEG,
- },
-};
-
-/* -----------------------------------------------------------------------------
- * Legacy g_webcam support
- */
-
-static const struct uvc_function_config g_webcam_config = {
- .control = {
- .intf = {
- .bInterfaceNumber = 0,
- },
- },
- .streaming = {
- .intf = {
- .bInterfaceNumber = 1,
- },
- .ep = {
- .bInterval = 1,
- .bMaxBurst = 0,
- .wMaxPacketSize = 1024,
- },
- .num_formats = 2,
- .formats = (struct uvc_function_config_format[]) {
- {
- .index = 1,
- .guid = UVC_GUID_FORMAT_YUY2,
- .fcc = V4L2_PIX_FMT_YUYV,
- .num_frames = 2,
- .frames = (struct uvc_function_config_frame[]) {
- {
- .index = 1,
- .width = 640,
- .height = 360,
- .num_intervals = 3,
- .intervals = (unsigned int[]) {
- 666666,
- 10000000,
- 50000000,
- },
- }, {
- .index = 2,
- .width = 1280,
- .height = 720,
- .num_intervals = 1,
- .intervals = (unsigned int[]) {
- 50000000,
- },
- },
- },
- }, {
- .index = 2,
- .guid = UVC_GUID_FORMAT_MJPEG,
- .fcc = V4L2_PIX_FMT_MJPEG,
- .num_frames = 2,
- .frames = (struct uvc_function_config_frame[]) {
- {
- .index = 1,
- .width = 640,
- .height = 360,
- .num_intervals = 3,
- .intervals = (unsigned int[]) {
- 666666,
- 10000000,
- 50000000,
- },
- }, {
- .index = 2,
- .width = 1280,
- .height = 720,
- .num_intervals = 1,
- .intervals = (unsigned int[]) {
- 50000000,
- },
- },
- },
- },
- },
- },
-};
-
-static int parse_legacy_g_webcam(const char *udc,
- struct uvc_function_config *fc)
-{
- void *memdup(const void *src, size_t size)
- {
- void *dst;
-
- dst = malloc(size);
- if (!dst)
- return NULL;
- memcpy(dst, src, size);
- return dst;
- }
-
- unsigned int i, j;
- size_t size;
-
- *fc = g_webcam_config;
-
- /*
- * We need to duplicate all sub-structures as the
- * configfs_free_uvc_function() function expects them to be dynamically
- * allocated.
- */
- size = sizeof *fc->streaming.formats * fc->streaming.num_formats;
- fc->streaming.formats = memdup(fc->streaming.formats, size);
-
- for (i = 0; i < fc->streaming.num_formats; ++i) {
- struct uvc_function_config_format *format =
- &fc->streaming.formats[i];
-
- size = sizeof *format->frames * format->num_frames;
- format->frames = memdup(format->frames, size);
-
- for (j = 0; j < format->num_frames; ++j) {
- struct uvc_function_config_frame *frame =
- &format->frames[j];
-
- size = sizeof *frame->intervals * frame->num_intervals;
- frame->intervals = memdup(frame->intervals, size);
- }
- }
-
- fc->video = udc_find_video_device(udc, NULL);
-
- return fc->video ? 0 : -ENODEV;
-}
-
-/* -----------------------------------------------------------------------------
- * ConfigFS support
- */
-
-/*
- * configfs_find_uvc_function - Find the ConfigFS full path for a UVC function
- * @function: The UVC function name
- *
- * Return a pointer to a newly allocated string containing the full ConfigFS
- * path to the function if the function is found. Otherwise return NULL. The
- * returned pointer must be freed by the caller with a call to free().
- */
-static char *configfs_find_uvc_function(const char *function)
-{
- const char *target = function ? function : "*";
- const char *root;
- char *func_path;
- char *path;
-
- /*
- * The function description can be provided as a path from the
- * usb_gadget root "g1/functions/uvc.0", or if there is no ambiguity
- * over the gadget name, a shortcut "uvc.0" can be provided.
- */
- if (!strchr(target, '/'))
- root = "/sys/kernel/config/usb_gadget/*/functions";
- else
- root = "/sys/kernel/config/usb_gadget";
-
- path = path_join(root, target);
-
- func_path = path_glob_first_match(path);
- free(path);
-
- return func_path;
-}
-
-/*
- * configfs_free_uvc_function - Free a uvc_function_config object
- * @fc: The uvc_function_config to be freed
- *
- * Free the given @fc function previously allocated by a call to
- * configfs_parse_uvc_function().
- */
-void configfs_free_uvc_function(struct uvc_function_config *fc)
-{
- unsigned int i, j;
-
- free(fc->udc);
- free(fc->video);
-
- for (i = 0; i < fc->streaming.num_formats; ++i) {
- struct uvc_function_config_format *format =
- &fc->streaming.formats[i];
-
- for (j = 0; j < format->num_frames; ++j) {
- struct uvc_function_config_frame *frame =
- &format->frames[j];
-
- free(frame->intervals);
- }
-
- free(format->frames);
- }
-
- free(fc->streaming.formats);
- free(fc);
-}
-
-#define configfs_parse_child(parent, child, cfg, parse) \
-({ \
- char *__path; \
- int __ret; \
- \
- __path = path_join((parent), (child)); \
- if (__path) { \
- __ret = parse(__path, (cfg)); \
- free(__path); \
- } else { \
- __ret = -ENOMEM; \
- } \
- \
- __ret; \
-})
-
-static int configfs_parse_interface(const char *path,
- struct uvc_function_config_interface *cfg)
-{
- int ret;
-
- ret = attribute_read_uint(path, "bInterfaceNumber",
- &cfg->bInterfaceNumber);
-
- return ret;
-}
-
-static int configfs_parse_control(const char *path,
- struct uvc_function_config_control *cfg)
-{
- int ret;
-
- ret = configfs_parse_interface(path, &cfg->intf);
-
- return ret;
-}
-
-static int configfs_parse_streaming_frame(const char *path,
- struct uvc_function_config_frame *frame)
-{
- char *intervals;
- char *p;
- int ret = 0;
-
- ret = ret ? : attribute_read_uint(path, "bFrameIndex", &frame->index);
- ret = ret ? : attribute_read_uint(path, "wWidth", &frame->width);
- ret = ret ? : attribute_read_uint(path, "wHeight", &frame->height);
- if (ret)
- return ret;
-
- intervals = attribute_read_str(path, "dwFrameInterval");
- if (!intervals)
- return -EINVAL;
-
- for (p = intervals; *p; ) {
- unsigned int interval;
- unsigned int *mem;
- char *endp;
- size_t size;
-
- interval = strtoul(p, &endp, 10);
- if (*endp != '\0' && *endp != '\n') {
- ret = -EINVAL;
- break;
- }
-
- p = *endp ? endp + 1 : endp;
-
- size = sizeof *frame->intervals * (frame->num_intervals + 1);
- mem = realloc(frame->intervals, size);
- if (!mem) {
- ret = -ENOMEM;
- break;
- }
-
- frame->intervals = mem;
- frame->intervals[frame->num_intervals++] = interval;
- }
-
- free(intervals);
-
- return ret;
-}
-
-static int configfs_parse_streaming_format(const char *path,
- struct uvc_function_config_format *format)
-{
- int frame_filter(const struct dirent *ent)
- {
- /* Accept all directories but "." and "..". */
- if (ent->d_type != DT_DIR)
- return 0;
- if (!strcmp(ent->d_name, "."))
- return 0;
- if (!strcmp(ent->d_name, ".."))
- return 0;
- return 1;
- }
-
- int frame_compare(const void *a, const void *b)
- {
- const struct uvc_function_config_frame *fa = a;
- const struct uvc_function_config_frame *fb = b;
-
- if (fa->index < fb->index)
- return -1;
- else if (fa->index == fb->index)
- return 0;
- else
- return 1;
- }
-
- struct dirent **entries;
- unsigned int i;
- int n_entries;
- int ret;
-
- ret = attribute_read_uint(path, "bFormatIndex", &format->index);
- if (ret < 0)
- return ret;
-
- ret = attribute_read(path, "guidFormat", format->guid,
- sizeof(format->guid));
- if (ret < 0)
- return ret;
- if (ret != 16)
- return -EINVAL;
-
- for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
- if (!memcmp(uvc_formats[i].guid, format->guid, 16)) {
- format->fcc = uvc_formats[i].fcc;
- break;
- }
- }
-
- /* Find all entries corresponding to a frame and parse them. */
- n_entries = scandir(path, &entries, frame_filter, alphasort);
- if (n_entries < 0)
- return -errno;
-
- if (n_entries == 0) {
- free(entries);
- return -EINVAL;
- }
-
- format->num_frames = n_entries;
- format->frames = calloc(sizeof *format->frames, format->num_frames);
- if (!format->frames)
- return -ENOMEM;
-
- for (i = 0; i < (unsigned int)n_entries; ++i) {
- char *frame;
-
- frame = path_join(path, entries[i]->d_name);
- if (!frame) {
- ret = -ENOMEM;
- goto done;
- }
-
- ret = configfs_parse_streaming_frame(frame, &format->frames[i]);
- free(frame);
- if (ret < 0)
- goto done;
- }
-
- /* Sort the frames by index. */
- qsort(format->frames, format->num_frames, sizeof *format->frames,
- frame_compare);
-
-done:
- for (i = 0; i < (unsigned int)n_entries; ++i)
- free(entries[i]);
- free(entries);
-
- return ret;
-}
-
-static int configfs_parse_streaming_header(const char *path,
- struct uvc_function_config_streaming *cfg)
-{
- int format_filter(const struct dirent *ent)
- {
- char *path;
- bool valid;
-
- /*
- * Accept all links that point to a directory containing a
- * "bFormatIndex" file.
- */
- if (ent->d_type != DT_LNK)
- return 0;
-
- path = path_join(ent->d_name, "bFormatIndex");
- if (!path)
- return 0;
-
- valid = access(path, R_OK);
- free(path);
- return valid;
- }
-
- int format_compare(const void *a, const void *b)
- {
- const struct uvc_function_config_format *fa = a;
- const struct uvc_function_config_format *fb = b;
-
- if (fa->index < fb->index)
- return -1;
- else if (fa->index == fb->index)
- return 0;
- else
- return 1;
- }
-
- struct dirent **entries;
- unsigned int i;
- int n_entries;
- int ret;
-
- /* Find all entries corresponding to a format and parse them. */
- n_entries = scandir(path, &entries, format_filter, alphasort);
- if (n_entries < 0)
- return -errno;
-
- if (n_entries == 0) {
- free(entries);
- return -EINVAL;
- }
-
- cfg->num_formats = n_entries;
- cfg->formats = calloc(sizeof *cfg->formats, cfg->num_formats);
- if (!cfg->formats)
- return -ENOMEM;
-
- for (i = 0; i < (unsigned int)n_entries; ++i) {
- char *format;
-
- format = path_join(path, entries[i]->d_name);
- if (!format) {
- ret = -ENOMEM;
- goto done;
- }
-
- ret = configfs_parse_streaming_format(format, &cfg->formats[i]);
- free(format);
- if (ret < 0)
- goto done;
- }
-
- /* Sort the formats by index. */
- qsort(cfg->formats, cfg->num_formats, sizeof *cfg->formats,
- format_compare);
-
-done:
- for (i = 0; i < (unsigned int)n_entries; ++i)
- free(entries[i]);
- free(entries);
-
- return ret;
-}
-
-static int configfs_parse_streaming(const char *path,
- struct uvc_function_config_streaming *cfg)
-{
- int link_filter(const struct dirent *ent)
- {
- /* Accept all links. */
- return ent->d_type == DT_LNK;
- }
-
- char *header;
- char *class;
- int ret;
-
- ret = configfs_parse_interface(path, &cfg->intf);
- if (ret < 0)
- return ret;
-
- /*
- * Handle the high-speed class descriptors only for now. Find the first
- * link to the class descriptors.
- */
- class = path_join(path, "class/hs");
- if (!class)
- return -ENOMEM;
-
- header = dir_first_match(class, link_filter);
- free(class);
- if (!header)
- return -EINVAL;
-
- ret = configfs_parse_streaming_header(header, cfg);
- free(header);
- return ret;
-}
-
-static int configfs_parse_uvc(const char *fpath,
- struct uvc_function_config *fc)
-{
- int ret = 0;
-
- ret = ret ? : configfs_parse_child(fpath, "control", &fc->control,
- configfs_parse_control);
- ret = ret ? : configfs_parse_child(fpath, "streaming", &fc->streaming,
- configfs_parse_streaming);
-
- /*
- * These parameters should be part of the streaming interface in
- * ConfigFS, but for legacy reasons they are located directly in the
- * function directory.
- */
- ret = ret ? : attribute_read_uint(fpath, "streaming_interval",
- &fc->streaming.ep.bInterval);
- ret = ret ? : attribute_read_uint(fpath, "streaming_maxburst",
- &fc->streaming.ep.bMaxBurst);
- ret = ret ? : attribute_read_uint(fpath, "streaming_maxpacket",
- &fc->streaming.ep.wMaxPacketSize);
-
- return ret;
-}
-
-/*
- * configfs_parse_uvc_function - Parse a UVC function configuration in ConfigFS
- * @function: The function name
- *
- * This function locates and parse the configuration of a UVC function in
- * ConfigFS as specified by the @function name argument. The function name can
- * be fully qualified with a gadget name (e.g. "g%u/functions/uvc.%u"), or as a
- * shortcut can be an unqualified function name (e.g. "uvc.%u"). When the
- * function name is unqualified, the first function matching the name in any
- * UDC will be returned.
- *
- * Return a pointer to a newly allocated UVC function configuration structure
- * that contains configuration parameters for the function, if the function is
- * found. Otherwise return NULL. The returned pointer must be freed by the
- * caller with a call to free().
- */
-struct uvc_function_config *configfs_parse_uvc_function(const char *function)
-{
- struct uvc_function_config *fc;
- char *fpath;
- int ret = 0;
-
- fc = malloc(sizeof *fc);
- if (fc == NULL)
- return NULL;
-
- memset(fc, 0, sizeof *fc);
-
- /* Find the function in ConfigFS. */
- fpath = configfs_find_uvc_function(function);
- if (!fpath) {
- /*
- * If the function can't be found attempt legacy parsing to
- * support the g_webcam gadget. The function parameter contains
- * a UDC name in that case.
- */
- ret = parse_legacy_g_webcam(function, fc);
- if (ret) {
- configfs_free_uvc_function(fc);
- fc = NULL;
- }
-
- return fc;
- }
-
- /*
- * Parse the function configuration. Remove the gadget name qualifier
- * from the function name, if any.
- */
- if (function)
- function = basename(function);
-
- fc->udc = attribute_read_str(fpath, "../../UDC");
- fc->video = udc_find_video_device(fc->udc, function);
- if (!fc->video) {
- ret = -ENODEV;
- goto done;
- }
-
- ret = configfs_parse_uvc(fpath, fc);
-
-done:
- if (ret) {
- configfs_free_uvc_function(fc);
- fc = NULL;
- }
-
- free(fpath);
-
- return fc;
-}