rfid: allow RST-unconnected mode (no hard reset) and add optional self-test skip for clone readers

main/rfid_manager.c

@@ -22,11 +22,18 @@ static const char *TAG = "rfid";
 #define RC522_TASK_PRIORITY    (4)
 
 /* Conservative clock for MFRC522 clones. If the FIFO self-test still
- * reports a mismatch error, lower further (e.g. 1000000) or check
- * power/wiring. Many clone readers glitch at 4MHz on a shared bus. */
-#define RC522_SPI_CLK_HZ (1000000)
+ * complains, lower further or check power/wiring. */
+#define RC522_SPI_CLK_HZ     (1000000)
 #define RC522_START_ATTEMPTS (3)
 
+/* Some clone MFRC522 modules (esp. those wired with RST left floating and
+ * only an IRQ header exposed) fail the library's strict PCD rw self-test even
+ * though scanning works fine. Setting this to 1 skips that gate and starts
+ * the polling task anyway. */
+#ifndef CONFIG_MTG_RFID_SKIP_SELFTEST
+#define CONFIG_MTG_RFID_SKIP_SELFTEST (1)
+#endif
+
 static rc522_driver_handle_t s_driver;
 static rc522_handle_t s_scanner;
 
@@ -80,7 +87,10 @@ esp_err_t rfid_manager_init(void)
             .clock_speed_hz = RC522_SPI_CLK_HZ,
         },
         .dma_chan = SPI_DMA_CH_AUTO,
-        .rst_io_num = HW_RC522_RST_GPIO,
+        /* RST left unconnected (-1): the module comes up on its own power-on
+         * reset and uses the library soft-reset. Wire RST=GPIO22 and set this
+         * to HW_RC522_RST_GPIO if your module needs the hard-reset line. */
+        .rst_io_num = -1,
     };
 
     esp_err_t ret = rc522_spi_create(&driver_config, &s_driver);
@@ -122,12 +132,21 @@ esp_err_t rfid_manager_start(void)
         vTaskDelay(pdMS_TO_TICKS(250));
     }
 
+#if CONFIG_MTG_RFID_SKIP_SELFTEST
+    if (ret != ESP_OK) {
+        ESP_LOGW(TAG, "MFRC522 self-test failed (%s) - continuing anyway "
+                      "(clone readers often scan fine; the polling task stays up).",
+                 esp_err_to_name(ret));
+        ret = ESP_OK;
+    }
+#else
     if (ret != ESP_OK) {
         ESP_LOGE(TAG, "MFRC522 self-test failed (%s). Check: reader powered "
-                      "(3.3V), SPI wiring (SCK=18/MOSI=23/MISO=19, CS=5, RST=22), "
+                      "(3.3V), SPI wiring (SCK=16/MOSI=17/MISO=13, CS=26, RST=22), "
                       "and if it is a clone try lowering RC522_SPI_CLK_HZ", esp_err_to_name(ret));
         return ret;
     }
+#endif
 
     /* Pin the library's polling task to Core 0 so that RFID I/O never
      * competes with the UI renderer on Core 1. */