AP_HAL_Linux: examples: small fixes to BusTest

- Fix char allocation
  - Fix coding style
  - Fix accessing dev->bus_type(): it's a function

libraries/AP_HAL_Linux/examples/BusTest/BusTest.cpp

@@ -1,5 +1,3 @@
-// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
-
 //
 // scan I2C and SPI buses for expected devices
 //
@@ -25,23 +23,25 @@ get_device(const char *name)
 {
     AP_HAL::OwnPtr<AP_HAL::Device> dev;
 
-    const char *spi_name = new char;
-    spi_name = hal.spi->get_device_name(0);
+    const char *spi_name = hal.spi->get_device_name(0);
     /* Dummy is the default device at index 0 
        if there isn't registered device for the target board.
     */
-    const char *dummy = {"**dummy**"};
+    const char *dummy = "**dummy**";
     if (!strcmp(dummy, spi_name)) {
         hal.console->printf("No devices, nothing to do.\n");
-        while(1) { hal.scheduler->delay(500); };
+        while (1) {
+            hal.scheduler->delay(500);
+        }
     }
 
     /* We get possible registered device count on the target board */
     uint8_t spicount = hal.spi->get_count();
     for (uint8_t ref = 0; ref < spicount; ref++) {
-        /* We get the name from the index and we compare
-           with our possible devices list.
-        */
+        /*
+         * We get the name from the index and we compare
+         * with our possible devices list.
+         */
         spi_name = hal.spi->get_device_name(ref);
         if (!strcmp(name, spi_name)) {
             dev = hal.spi->get_device(spi_name);
@@ -67,34 +67,36 @@ void loop(void)
 
     for (uint8_t i = 0; i < ARRAY_SIZE(whoami_list); i++) {
         dev = get_device(whoami_list[i].name);
-        if (dev) {
-
-            if (dev->bus_type == AP_HAL::Device::BusType::BUS_TYPE_SPI) {
-                bus_type = "SPI";
-            } else {
-                bus_type = "I2C";
-            }
-
-            hal.console->printf("Device %s registered on %s bus\n", whoami_list[i].name, bus_type);
-            hal.console->printf("Trying to send data...\n");
-
-            spi_sem = dev->get_semaphore();
-            if (!spi_sem->take(1000)) {
-                hal.console->printf("Failed to get SPI semaphore for %s\n", whoami_list[i].name);
-                break;
-            }
-            uint8_t tx[2] = { whoami_list[i].whoami_reg, 0 };
-            uint8_t rx[2] = { 0, 0 };
-            dev->transfer(tx, sizeof(tx), rx, sizeof(rx));
-            if (rx[1] != 0) {
-                hal.console->printf("WHO_AM_I for %s: 0x%02x\n\n", whoami_list[i].name, (unsigned)rx[1]);
-            } else {
-                hal.console->printf("No response %s!\n\n", whoami_list[i].name);
-                break;
-            }
-            spi_sem->give();
+        if (!dev) {
+            continue;
+        }
+
+        if (dev->bus_type() == AP_HAL::Device::BusType::BUS_TYPE_SPI) {
+            bus_type = "SPI";
+        } else {
+            bus_type = "I2C";
         }
+
+        hal.console->printf("Device %s registered on %s bus\n", whoami_list[i].name, bus_type);
+        hal.console->printf("Trying to send data...\n");
+
+        spi_sem = dev->get_semaphore();
+        if (!spi_sem->take(1000)) {
+            hal.console->printf("Failed to get SPI semaphore for %s\n", whoami_list[i].name);
+            break;
+        }
+        uint8_t tx[2] = { whoami_list[i].whoami_reg, 0 };
+        uint8_t rx[2] = { 0, 0 };
+        dev->transfer(tx, sizeof(tx), rx, sizeof(rx));
+        if (rx[1] != 0) {
+            hal.console->printf("WHO_AM_I for %s: 0x%02x\n\n", whoami_list[i].name, (unsigned)rx[1]);
+        } else {
+            hal.console->printf("No response %s!\n\n", whoami_list[i].name);
+            break;
+        }
+        spi_sem->give();
     }
+
     hal.scheduler->delay(1000);
 }