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)));
{
/* 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,
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, "%s. Transferred: %d (expected %u)\n",
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, "%s. Transferred: %d (expected %u)\n",
* set up */
static void log_message(am7xxx_context *ctx,
int level,
- const char *function,
+ const char *function_name,
int line,
const char *fmt,
...)
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, ": ");
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));
/* the usb device has already been opened */
if ((*dev)->usb_device) {
- debug(ctx, "(*dev)->usb_device already set\n");
ret = 1;
goto out;
}
if (current_configuration != (*dev)->desc->configuration) {
/*
- * In principle kernel drivers bound to each interface should
- * be detached before setting the configuration, but in
- * practice this is not necessary for most devices.
+ * 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:
*
- * For example something like the following function would be
- * called:
- * libusb_detach_all_kernel_drivers((*dev)->usb_device);
+ * 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 (current_configuration != (*dev)->desc->configuration) {
- debug(ctx, "libusb configuration changed (expected: %hhu, current: %hhu\n",
+ debug(ctx, "libusb configuration changed (expected: %hhu, current: %d)\n",
(*dev)->desc->configuration, current_configuration);
ret = -EINVAL;
goto out_libusb_release_interface;
*ctx = malloc(sizeof(**ctx));
if (*ctx == NULL) {
fatal("cannot allocate the context (%s)\n", strerror(errno));
- ret = -ENOMEM;
- goto out;
+ return -ENOMEM;
}
memset(*ctx, 0, sizeof(**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);
* is the first one to be sent to the device in order for it to
* successfully return the correct device information.
*
- * So, if there is not a cached version of it (from a previous open),
- * we ask for device info at open time,
+ * NOTE: am7xxx_get_device_info() will fetch the actual device info
+ * from the device only the very first time it's called for a given
+ * device, otherwise, it'll return a cached version of the device info
+ * (from a previous call to am7xxx_open_device(), for instance).
*/
- if ((*dev)->device_info == NULL) {
- ret = am7xxx_get_device_info(*dev, NULL);
- if (ret < 0)
- error(ctx, "cannot get device info\n");
- }
+ ret = am7xxx_get_device_info(*dev, NULL);
+ if (ret < 0)
+ error(ctx, "cannot get device info\n");
out:
return ret;
int ret;
struct am7xxx_header h;
- if (dev->device_info) {
- memcpy(device_info, dev->device_info, sizeof(*device_info));
- return 0;
- }
+ /* if there is a cached copy of the device info, just return that */
+ if (dev->device_info)
+ goto return_value;
ret = send_command(dev, AM7XXX_PACKET_TYPE_DEVINFO);
if (ret < 0)
dev->device_info->unknown1 = h.header_data.devinfo.unknown1;
#endif
+return_value:
+ if (device_info)
+ memcpy(device_info, dev->device_info, sizeof(*device_info));
return 0;
}
unsigned int *scaled_width,
unsigned int *scaled_height)
{
-
am7xxx_device_info device_info;
float width_ratio;
float height_ratio;