Add USB sys file-system support Thu, 02 Oct 2008 00:19:35 +0100 Add USB sys file-system support This patch adds support for host USB devices discovered via: /sys/bus/usb/devices/* and opened from /dev/bus/usb/*/* /dev/bus/usb/devices and opened from /dev/bus/usb/*/* in addition to the existing discovery via: /proc/bus/usb/devices and opened from /proc/bus/usb/*/* Signed-off-by: TJ --- usb-linux.c | 228 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 218 insertions(+), 10 deletions(-) diff --git a/usb-linux.c b/usb-linux.c index c5da5b5..6113a0c 100644 --- a/usb-linux.c +++ b/usb-linux.c @@ -7,6 +7,10 @@ * Support for host device auto connect & disconnect * Major rewrite to support fully async operation * + * Copyright 2008 TJ + * Added flexible support for /dev/bus/usb /sys/bus/usb/devices in addition + * to the legacy /proc/bus/usb USB device discovery and handling + * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights @@ -72,9 +76,20 @@ static int usb_host_find_device(int *pbus_num, int *paddr, #define dprintf(...) #endif -#define USBDEVFS_PATH "/proc/bus/usb" +#define USBPROCBUS_PATH "/proc/bus/usb" #define PRODUCT_NAME_SZ 32 #define MAX_ENDPOINTS 16 +#define USBDEVBUS_PATH "/dev/bus/usb" +#define USBSYSBUS_PATH "/sys/bus/usb" + +static char *usb_host_device_path; + +#define USB_FS_NONE 0 +#define USB_FS_PROC 1 +#define USB_FS_DEV 2 +#define USB_FS_SYS 3 + +static int usb_fs_type; /* endpoint association data */ struct endp_data { @@ -890,13 +905,18 @@ static USBDevice *usb_host_device_open_addr(int bus_num, int addr, const char *p printf("husb: open device %d.%d\n", bus_num, addr); - snprintf(buf, sizeof(buf), USBDEVFS_PATH "/%03d/%03d", + if (!usb_host_device_path) { + perror("husb: USB Host Device Path not set"); + goto fail; + } + snprintf(buf, sizeof(buf), "%s/%03d/%03d", usb_host_device_path, bus_num, addr); fd = open(buf, O_RDWR | O_NONBLOCK); if (fd < 0) { perror(buf); goto fail; } + dprintf("husb: opened %s\n", buf); /* read the device description */ dev->descr_len = read(fd, dev->descr, sizeof(dev->descr)); @@ -1038,23 +1058,33 @@ static int get_tag_value(char *buf, int buf_size, return q - buf; } -static int usb_host_scan(void *opaque, USBScanFunc *func) +/* + * Use /proc/bus/usb/devices or /dev/bus/usb/devices file to determine + * host's USB devices. This is legacy support since many distributions + * are moving to /sys/bus/usb + */ +static int usb_host_scan_dev(void *opaque, USBScanFunc *func) { - FILE *f; + FILE *f = 0; char line[1024]; char buf[1024]; int bus_num, addr, speed, device_count, class_id, product_id, vendor_id; - int ret; char product_name[512]; + int ret = 0; - f = fopen(USBDEVFS_PATH "/devices", "r"); + if (!usb_host_device_path) { + perror("husb: USB Host Device Path not set"); + goto the_end; + } + snprintf(line, sizeof(line), "%s/devices", usb_host_device_path); + f = fopen(line, "r"); if (!f) { - term_printf("husb: could not open %s\n", USBDEVFS_PATH "/devices"); - return 0; + perror("husb: cannot open devices file"); + goto the_end; } + device_count = 0; bus_num = addr = speed = class_id = product_id = vendor_id = 0; - ret = 0; for(;;) { if (fgets(line, sizeof(line), f) == NULL) break; @@ -1111,7 +1141,185 @@ static int usb_host_scan(void *opaque, USBScanFunc *func) product_id, product_name, speed); } the_end: - fclose(f); + if (f) + fclose(f); + return ret; +} + +/* + * Read sys file-system device file + * + * @line address of buffer to put file contents in + * @line_size size of line + * @device_file path to device file (printf format string) + * @device_name device being opened (inserted into device_file) + * + * @return 0 failed, 1 succeeded ('line' contains data) + */ +static int usb_host_read_file(char *line, size_t line_size, const char *device_file, const char *device_name) +{ + FILE *f; + int ret = 0; + char filename[PATH_MAX]; + + snprintf(filename, PATH_MAX, device_file, device_name); + f = fopen(filename, "r"); + if (f) { + fgets(line, line_size, f); + fclose(f); + ret = 1; + } else { + term_printf("husb: could not open %s\n", filename); + } + + return ret; +} + +/* + * Use /sys/bus/usb/devices/ directory to determine host's USB + * devices. + * + * This code is based on Robert Schiele's original patches posted to + * the Novell bug-tracker https://bugzilla.novell.com/show_bug.cgi?id=241950 + */ +static int usb_host_scan_sys(void *opaque, USBScanFunc *func) +{ + DIR *dir = 0; + char line[1024]; + int bus_num, addr, speed, class_id, product_id, vendor_id; + int ret = 0; + char product_name[512]; + struct dirent *de; + + dir = opendir(USBSYSBUS_PATH "/devices"); + if (!dir) { + perror("husb: cannot open devices directory"); + goto the_end; + } + + while ((de = readdir(dir))) { + if (de->d_name[0] != '.' && !strchr(de->d_name, ':')) { + char *tmpstr = de->d_name; + if (!strncmp(de->d_name, "usb", 3)) + tmpstr += 3; + bus_num = atoi(tmpstr); + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/devnum", de->d_name)) + goto the_end; + if (sscanf(line, "%d", &addr) != 1) + goto the_end; + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/bDeviceClass", de->d_name)) + goto the_end; + if (sscanf(line, "%x", &class_id) != 1) + goto the_end; + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/idVendor", de->d_name)) + goto the_end; + if (sscanf(line, "%x", &vendor_id) != 1) + goto the_end; + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/idProduct", de->d_name)) + goto the_end; + if (sscanf(line, "%x", &product_id) != 1) + goto the_end; + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/product", de->d_name)) { + *product_name = 0; + } else { + if (strlen(line) > 0) + line[strlen(line) - 1] = '\0'; + pstrcpy(product_name, sizeof(product_name), line); + } + + if (!usb_host_read_file(line, sizeof(line), USBSYSBUS_PATH "/devices/%s/speed", de->d_name)) + goto the_end; + if (!strcmp(line, "480\n")) + speed = USB_SPEED_HIGH; + else if (!strcmp(line, "1.5\n")) + speed = USB_SPEED_LOW; + else + speed = USB_SPEED_FULL; + + ret = func(opaque, bus_num, addr, class_id, vendor_id, + product_id, product_name, speed); + if (ret) + goto the_end; + } + } + the_end: + if (dir) + closedir(dir); + return ret; +} + +/* + * Determine how to access the host's USB devices and call the + * specific support function. + */ +static int usb_host_scan(void *opaque, USBScanFunc *func) +{ + FILE *f = 0; + DIR *dir = 0; + int ret = 0; + const char *devices = "/devices"; + const char *opened = "husb: opened %s%s\n"; + const char *fs_type[] = {"unknown", "proc", "dev", "sys"}; + char devpath[PATH_MAX]; + + /* only check the host once */ + if (!usb_fs_type) { + f = fopen(USBPROCBUS_PATH "/devices", "r"); + if (f) { + /* devices found in /proc/bus/usb/ */ + strcpy(devpath, USBPROCBUS_PATH); + usb_fs_type = USB_FS_PROC; + fclose(f); + dprintf(opened, USBPROCBUS_PATH, devices); + } + /* try additional methods if an access method hasn't been found yet */ + f = fopen(USBDEVBUS_PATH "/devices", "r"); + if (!usb_fs_type && f) { + /* devices found in /dev/bus/usb/ */ + strcpy(devpath, USBDEVBUS_PATH); + usb_fs_type = USB_FS_DEV; + fclose(f); + dprintf(opened, USBDEVBUS_PATH, devices); + } + dir = opendir(USBSYSBUS_PATH "/devices"); + if (!usb_fs_type && dir) { + /* devices found in /dev/bus/usb/ (yes - not a mistake!) */ + strcpy(devpath, USBDEVBUS_PATH); + usb_fs_type = USB_FS_SYS; + closedir(dir); + dprintf(opened, USBSYSBUS_PATH, devices); + } else { + term_printf("husb: unable to access USB devices\n"); + goto the_end; + } + + /* the module setting (used later for opening devices) */ + usb_host_device_path = qemu_mallocz(strlen(devpath)+1); + if (usb_host_device_path) { + strcpy(usb_host_device_path, devpath); + term_printf("husb: using %s file-system with %s\n", fs_type[usb_fs_type], usb_host_device_path); + } else { + /* out of memory? */ + perror("husb: unable to allocate memory for device path"); + goto the_end; + } + } + + switch (usb_fs_type) { + case USB_FS_PROC: + case USB_FS_DEV: + ret = usb_host_scan_dev(opaque, func); + break; + case USB_FS_SYS: + ret = usb_host_scan_sys(opaque, func); + break; + } + the_end: return ret; } -- 1.5.4.3