X-Git-Url: https://git.ao2.it/libam7xxx.git/blobdiff_plain/18abce2d438f825a38f52df6d904088adda4c890..189a9391eb6cbc584cc0cc9d72dd4b91b9c71f4f:/src/am7xxx.c?ds=sidebyside diff --git a/src/am7xxx.c b/src/am7xxx.c index ebc403e..76df87d 100644 --- a/src/am7xxx.c +++ b/src/am7xxx.c @@ -34,7 +34,7 @@ * taken from: http://unixwiz.net/techtips/gnu-c-attributes.html) */ #ifndef __GNUC__ -# define __attribute__(x) /*NOTHING*/ +# define __attribute__(x) /* NOTHING */ #endif /* Control shared library symbols visibility */ @@ -53,7 +53,7 @@ static void log_message(am7xxx_context *ctx, int level, - const char *function, + const char *function_name, int line, const char *fmt, ...) __attribute__ ((format (printf, 5, 6))); @@ -341,7 +341,7 @@ static inline unsigned int in_80chars(unsigned int i) { /* The 3 below is the length of "xx " where xx is the hex string * representation of a byte */ - return ((i+1) % (80/3)); + return ((i + 1) % (80 / 3)); } static void trace_dump_buffer(am7xxx_context *ctx, const char *message, @@ -381,12 +381,13 @@ static void trace_dump_buffer(am7xxx_context *ctx, const char *message, static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len) { int ret; - int transferred = 0; + int transferred; + transferred = 0; ret = libusb_bulk_transfer(dev->usb_device, 0x81, buffer, len, &transferred, 0); if (ret != 0 || (unsigned int)transferred != len) { - error(dev->ctx, "ret: %d\ttransferred: %d (expected %u)\n", - ret, transferred, len); + error(dev->ctx, "%s. Transferred: %d (expected %u)\n", + libusb_error_name(ret), transferred, len); return ret; } @@ -398,14 +399,15 @@ static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len) static int send_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len) { int ret; - int transferred = 0; + int transferred; trace_dump_buffer(dev->ctx, "sending -->", buffer, len); + transferred = 0; ret = libusb_bulk_transfer(dev->usb_device, 0x1, buffer, len, &transferred, 0); if (ret != 0 || (unsigned int)transferred != len) { - error(dev->ctx, "ret: %d\ttransferred: %d (expected %u)\n", - ret, transferred, len); + error(dev->ctx, "%s. Transferred: %d (expected %u)\n", + libusb_error_name(ret), transferred, len); return ret; } @@ -489,8 +491,8 @@ static int send_data_async(am7xxx_device *dev, uint8_t *buffer, unsigned int len /* Make a copy of the buffer so the caller can safely reuse it just * after libusb_submit_transfer() has returned. This technique - * requires more allocations than a proper double-buffering approach - * but it takes a lot less code. */ + * requires more dynamic allocations compared to a proper + * double-buffering approach but it takes a lot less code. */ transfer_buffer = malloc(len); if (transfer_buffer == NULL) { error(dev->ctx, "cannot allocate transfer buffer (%s)\n", @@ -626,7 +628,7 @@ static int send_command(am7xxx_device *dev, am7xxx_packet_type type) * set up */ static void log_message(am7xxx_context *ctx, int level, - const char *function, + const char *function_name, int line, const char *fmt, ...) @@ -634,8 +636,8 @@ static void log_message(am7xxx_context *ctx, va_list ap; if (level == AM7XXX_LOG_FATAL || (ctx && level <= ctx->log_level)) { - if (function) { - fprintf(stderr, "%s", function); + if (function_name) { + fprintf(stderr, "%s", function_name); if (line) fprintf(stderr, "[%d]", line); fprintf(stderr, ": "); @@ -662,7 +664,7 @@ static am7xxx_device *add_new_device(am7xxx_context *ctx, new_device = malloc(sizeof(*new_device)); if (new_device == NULL) { - fatal("cannot allocate a new device (%s)\n", strerror(errno)); + debug(ctx, "cannot allocate a new device (%s)\n", strerror(errno)); return NULL; } memset(new_device, 0, sizeof(*new_device)); @@ -702,6 +704,119 @@ static am7xxx_device *find_device(am7xxx_context *ctx, return current; } +static int open_device(am7xxx_context *ctx, + unsigned int device_index, + libusb_device *usb_dev, + am7xxx_device **dev) +{ + int ret; + int current_configuration; + + *dev = find_device(ctx, device_index); + if (*dev == NULL) { + ret = -ENODEV; + goto out; + } + + /* the usb device has already been opened */ + if ((*dev)->usb_device) { + ret = 1; + goto out; + } + + ret = libusb_open(usb_dev, &((*dev)->usb_device)); + if (ret < 0) { + debug(ctx, "libusb_open failed: %s\n", libusb_error_name(ret)); + goto out; + } + + /* XXX, the device is now open, if any of the calls below fail we need + * to close it again before bailing out. + */ + + current_configuration = -1; + ret = libusb_get_configuration((*dev)->usb_device, + ¤t_configuration); + if (ret < 0) { + debug(ctx, "libusb_get_configuration failed: %s\n", + libusb_error_name(ret)); + goto out_libusb_close; + } + + if (current_configuration != (*dev)->desc->configuration) { + /* + * In principle, before setting a new configuration, kernel + * drivers should be detached from _all_ interfaces; for + * example calling something like the following "invented" + * function _before_ setting the new configuration: + * + * libusb_detach_all_kernel_drivers((*dev)->usb_device); + * + * However, in practice, this is not necessary for most + * devices as they have only one configuration. + * + * When a device only has one configuration: + * + * - if there was a kernel driver bound to the device, it + * had already set the configuration and the call below + * will be skipped; + * + * - if no kernel driver was bound to the device, the call + * below will suceed. + */ + ret = libusb_set_configuration((*dev)->usb_device, + (*dev)->desc->configuration); + if (ret < 0) { + debug(ctx, "libusb_set_configuration failed: %s\n", + libusb_error_name(ret)); + debug(ctx, "Cannot set configuration %hhu\n", + (*dev)->desc->configuration); + goto out_libusb_close; + } + } + + libusb_set_auto_detach_kernel_driver((*dev)->usb_device, 1); + + ret = libusb_claim_interface((*dev)->usb_device, + (*dev)->desc->interface_number); + if (ret < 0) { + debug(ctx, "libusb_claim_interface failed: %s\n", + libusb_error_name(ret)); + debug(ctx, "Cannot claim interface %hhu\n", + (*dev)->desc->interface_number); + goto out_libusb_close; + } + + /* Checking that the configuration has not changed, as suggested in + * http://libusb.sourceforge.net/api-1.0/caveats.html + */ + current_configuration = -1; + ret = libusb_get_configuration((*dev)->usb_device, + ¤t_configuration); + if (ret < 0) { + debug(ctx, "libusb_get_configuration after claim failed: %s\n", + libusb_error_name(ret)); + goto out_libusb_release_interface; + } + + if (current_configuration != (*dev)->desc->configuration) { + debug(ctx, "libusb configuration changed (expected: %hhu, current: %d\n", + (*dev)->desc->configuration, current_configuration); + ret = -EINVAL; + goto out_libusb_release_interface; + } +out: + return ret; + +out_libusb_release_interface: + libusb_release_interface((*dev)->usb_device, + (*dev)->desc->interface_number); +out_libusb_close: + libusb_close((*dev)->usb_device); + (*dev)->usb_device = NULL; + return ret; +} + typedef enum { SCAN_OP_BUILD_DEVLIST, SCAN_OP_OPEN_DEVICE, @@ -711,13 +826,14 @@ typedef enum { * This is where the central logic of multi-device support is. * * When 'op' == SCAN_OP_BUILD_DEVLIST the parameters 'open_device_index' and - * 'dev' are ignored; the function returns 0 on success and a negative value + * 'dev' are ignored; the function returns 0 on success or a negative value * on error. * * When 'op' == SCAN_OP_OPEN_DEVICE the function opens the supported USB * device with index 'open_device_index' and returns the correspondent - * am7xxx_device in the 'dev' parameter; the function returns 0 on success, - * 1 if the device was already open and a negative value on error. + * am7xxx_device in the 'dev' parameter; the function returns the value from + * open_device(), which is 0 on success, 1 if the device was already open or + * a negative value on error. * * NOTES: * if scan_devices() fails when called with 'op' == SCAN_OP_BUILD_DEVLIST, @@ -728,7 +844,7 @@ static int scan_devices(am7xxx_context *ctx, scan_op op, unsigned int open_device_index, am7xxx_device **dev) { ssize_t num_devices; - libusb_device** list; + libusb_device **list; unsigned int current_index; int i; int ret; @@ -780,51 +896,16 @@ static int scan_devices(am7xxx_context *ctx, scan_op op, } else if (op == SCAN_OP_OPEN_DEVICE && current_index == open_device_index) { - *dev = find_device(ctx, open_device_index); - if (*dev == NULL) { - ret = -ENODEV; - goto out; - } - - /* the usb device has already been opened */ - if ((*dev)->usb_device) { - debug(ctx, "(*dev)->usb_device already set\n"); - ret = 1; - goto out; - } - - ret = libusb_open(list[i], &((*dev)->usb_device)); - if (ret < 0) { - debug(ctx, "libusb_open failed\n"); - goto out; - } - - /* XXX, the device is now open, if any - * of the calls below fail we need to - * close it again before bailing out. - */ - - ret = libusb_set_configuration((*dev)->usb_device, - (*dev)->desc->configuration); - if (ret < 0) { - debug(ctx, "libusb_set_configuration failed\n"); - debug(ctx, "Cannot set configuration %hhu\n", - (*dev)->desc->configuration); - goto out_libusb_close; - } - - ret = libusb_claim_interface((*dev)->usb_device, - (*dev)->desc->interface_number); - if (ret < 0) { - debug(ctx, "libusb_claim_interface failed\n"); - debug(ctx, "Cannot claim interface %hhu\n", - (*dev)->desc->interface_number); -out_libusb_close: - libusb_close((*dev)->usb_device); - (*dev)->usb_device = NULL; - goto out; - } + ret = open_device(ctx, + open_device_index, + list[i], + dev); + if (ret < 0) + debug(ctx, "open_device failed\n"); + /* exit the loop unconditionally after + * attempting to open the device + * requested by the user */ goto out; } current_index++; @@ -832,7 +913,8 @@ out_libusb_close: } } - /* if we made it up to here we didn't find any device to open */ + /* if we made it up to here when op == SCAN_OP_OPEN_DEVICE, + * no devices to open had been found. */ if (op == SCAN_OP_OPEN_DEVICE) { error(ctx, "Cannot find any device to open\n"); ret = -ENODEV; @@ -1020,8 +1102,10 @@ AM7XXX_PUBLIC int am7xxx_init(am7xxx_context **ctx) (*ctx)->log_level = AM7XXX_LOG_TRACE; ret = libusb_init(&((*ctx)->usb_context)); - if (ret < 0) + if (ret < 0) { + error(*ctx, "libusb_init failed: %s\n", libusb_error_name(ret)); goto out_free_context; + } libusb_set_debug((*ctx)->usb_context, LIBUSB_LOG_LEVEL_INFO);