PMW3389 Revert Firmware load during Initilization (#15859)

docs/feature_pointing_device.md

@@ -174,7 +174,6 @@ The PMW 3389 is an SPI driven optical sensor, that uses a built in IR LED for su
 |`PMW3389_SPI_DIVISOR`            | (Optional) Sets the SPI Divisor used for SPI communication.                                | _varies_      |
 |`PMW3389_LIFTOFF_DISTANCE`       | (Optional) Sets the lift off distance at run time                                          | `0x02`        |
 |`ROTATIONAL_TRANSFORM_ANGLE`     | (Optional) Allows for the sensor data to be rotated +/- 30 degrees directly in the sensor. | `0`           |
-|`PMW3389_LEGACY_FIRMWARE_UPLOAD` | (Optional) Switches to older, manual upload of firmware, for compatibility.                | _not defined_ |
 
 The CPI range is 50-16000, in increments of 50. Defaults to 2000 CPI.
 

drivers/sensors/pmw3389.c

@@ -210,16 +210,14 @@ void pmw3389_upload_firmware(void) {
     spi_write(REG_SROM_Load_Burst | 0x80);
     wait_us(15);
 
-#ifdef PMW3389_LEGACY_FIRMWARE_UPLOAD
+    // legacy only for PMW3389 spi_transmit failed to load firmware
     unsigned char c;
     for (int i = 0; i < FIRMWARE_LENGTH; i++) {
         c = (unsigned char)pgm_read_byte(firmware_data + i);
         spi_write(c);
         wait_us(15);
     }
-#else
-    spi_transmit(firmware_data, sizeof(firmware_data));
-#endif
+
     wait_us(200);
 
     pmw3389_read(REG_SROM_ID);