refactor(uvc): Added possibility to print supported formats

Author: roma-jam

host/class/uvc/usb_host_uvc/Kconfig

@@ -6,6 +6,15 @@ menu "USB-Driver: UVC Host"
         help
             Print UVC Configuration Descriptor to console.
 
+    config UVC_HOST_PRINT_SUPPORTED_FORMATS
+        bool "Print supported formats"
+        default n
+        help
+            When the stream parameters are unknown, this feature could be enabled to show supported formats by the camera.
+            When enabled, the driver displays interface number, resolution, format and default FPS.
+
+            Disabled by default.
+
     config UVC_HOST_INTERVAL_ARRAY_SIZE
         int "Size of the interval array in uvc_host_frame_info_t"
         default 3

host/class/uvc/usb_host_uvc/include/usb/uvc_host.h

@@ -38,6 +38,7 @@ enum uvc_host_stream_format {
     UVC_VS_FORMAT_YUY2,
     UVC_VS_FORMAT_H264,
     UVC_VS_FORMAT_H265,
+    UVC_VS_FORMAT_MAX
 };
 
 /**

host/class/uvc/usb_host_uvc/uvc_descriptor_parsing.c

@@ -7,13 +7,33 @@
 #include <inttypes.h>
 #include <string.h> // strncmp for guid format parsing
 #include <math.h>   // fabsf for float comparison
+#include "esp_log.h"
 #include "usb/usb_helpers.h"
 #include "usb/uvc_host.h"
 #include "uvc_check_priv.h"
 #include "uvc_descriptors_priv.h"
+#include "sdkconfig.h"
+
+#define UVC_PRINT_SUPPORTED_FORMATS     CONFIG_UVC_HOST_PRINT_SUPPORTED_FORMATS
 
 #define FLOAT_EQUAL(a, b) (fabsf(a - b) < 0.0001f) // For comparing float values with acceptable difference (epsilon value)
 
+#if (UVC_PRINT_SUPPORTED_FORMATS)
+static const char *format_to_string[UVC_VS_FORMAT_MAX] = {
+    "Undefined",
+    "MJPEG",
+    "YUY2",
+    "H264",
+    "H265",
+};
+
+static inline uint32_t make_fps(uint32_t frame_interval)
+{
+    return (frame_interval != 0) ? (10000000 / frame_interval) : 0;
+}
+#endif // UVC_PRINT_SUPPORTED_FORMATS
+
+
 static const uvc_vs_input_header_desc_t *uvc_desc_get_streaming_input_header(const usb_config_desc_t *cfg_desc, uint8_t bInterfaceNumber)
 {
     UVC_CHECK(cfg_desc, NULL);
@@ -365,16 +385,32 @@ esp_err_t uvc_desc_get_streaming_interface_num(
     }
     *bcdUVC = vc_header_desc->bcdUVC;
 
-    // Find video streaming interface that offers the requested format
-    for (int streaming_if = 0; streaming_if < vc_header_desc->bInCollection; streaming_if++) {
-        uint8_t current_bInterfaceNumber = vc_header_desc->baInterfaceNr[streaming_if];
-        if (uvc_desc_is_format_supported(cfg_desc, current_bInterfaceNumber, vs_format)) {
-            *bInterfaceNumber = current_bInterfaceNumber;
-            ret = ESP_OK;
-            break;
-        }
+#if (UVC_PRINT_SUPPORTED_FORMATS)
+    uvc_host_frame_info_t frames[20];
+    size_t size = 20;
+    for (int iface = 0; iface < vc_header_desc->bInCollection; iface++) {
+        ESP_ERROR_CHECK(uvc_desc_get_frame_list(cfg_desc, uvc_index, &frames, &size));
+        ESP_LOGW("UVC", "Supported frame formats:");
+        ESP_LOGW("UVC", "\t%dx%d, %s, default FPS: %d",
+                 frames[i].h_res, frames[i].v_res,
+                 format_to_string[frames[i].format],
+                 make_fps(frames[i].default_interval));
     }
-    return ret;
+}
+#endif // UVC_PRINT_SUPPORTED_FORMATS
+
+// Find video streaming interface that offers the requested format
+for (int streaming_if = 0; streaming_if < vc_header_desc->bInCollection; streaming_if++)
+{
+    uint8_t current_bInterfaceNumber = vc_header_desc->baInterfaceNr[streaming_if];
+    if (uvc_desc_is_format_supported(cfg_desc, current_bInterfaceNumber, vs_format)) {
+        *bInterfaceNumber = current_bInterfaceNumber;
+        ret = ESP_OK;
+        break;
+    }
+}
+
+return ret;
 }
 
 bool uvc_desc_is_uvc_device(const usb_config_desc_t *cfg_desc)