API change for libx52

- libx52_init returns the libx52_device in an output parameter and
  returns a libx52_error_code
- Make all functions return libx52_error_code
- Update package version to indicate incompatible API change

ChangeLog.md

@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file.
 The format is based upon [Keep a Changelog].
 
 ## [Unreleased]
+### Changed
+- `libx52_init` now returns a `libx52_error_code`, and returns the
+  `libx52_device` pointer in an output parameter.
+- All libx52 APIs now return a `libx52_error_code` indicating the error.
 
 ## [0.1.2] - 2017-08-17
 ### Added

configure.ac

@@ -1,4 +1,4 @@
-AC_INIT([x52pro-linux], [0.1.2], [nirenjan@gmail.com])
+AC_INIT([x52pro-linux], [0.2.0], [nirenjan@gmail.com])
 AC_CONFIG_MACRO_DIR([m4])
 AM_INIT_AUTOMAKE([-Wall -Werror foreign subdir-objects])
 AC_PROG_CC

lib/libx52/Makefile.am

@@ -5,7 +5,7 @@ lib_LTLIBRARIES = libx52.la
 # Core libx52 library
 # This library handles the USB communication between the host and the X52
 libx52_la_SOURCES = x52_control.c x52_core.c x52_date_time.c x52_mfd_led.c
-libx52_la_LDFLAGS = -version-info 3:0:2 -lusb-1.0
+libx52_la_LDFLAGS = -version-info 4:0:2 -lusb-1.0
 
 # Header files that need to be copied
 x52includedir = $(includedir)/x52pro

lib/libx52/libx52.h

@@ -1,7 +1,7 @@
 /*
  * Saitek X52 Pro MFD & LED driver
  *
- * Copyright (C) 2012-2015 Nirenjan Krishnan (nirenjan@nirenjan.org)
+ * Copyright (C) 2012-2017 Nirenjan Krishnan (nirenjan@nirenjan.org)
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License as
@@ -131,6 +131,37 @@ typedef enum {
     LIBX52_LED_STATE_GREEN,
 } libx52_led_state;
 
+/**
+ * @brief LibX52 Error codes
+ *
+ * Error codes returned by libx52
+ */
+typedef enum {
+    /** No error, indicates success */
+    LIBX52_SUCCESS = 0,
+
+    /** Initialization failure */
+    LIBX52_ERROR_INIT_FAILURE,
+
+    /** Out of memory */
+    LIBX52_ERROR_OUT_OF_MEMORY,
+
+    /** Invalid parameter(s) */
+    LIBX52_ERROR_INVALID_PARAM,
+
+    /** Not supported */
+    LIBX52_ERROR_NOT_SUPPORTED,
+
+    /** No change necessary, try again */
+    LIBX52_ERROR_TRY_AGAIN,
+
+    /** Clock timezone out of range */
+    LIBX52_ERROR_OUT_OF_RANGE,
+
+    /** Error encountered during USB interaction */
+    LIBX52_ERROR_USB_FAILURE,
+} libx52_error_code;
+
 /**
  * @brief Initialize the X52 library
  *
@@ -144,9 +175,11 @@ typedef enum {
  * This function does not support hotplugging. The joystick must be plugged in
  * before calling this function.
  *
- * @returns a pointer to the detected \ref libx52_device
+ * @param[out]  dev     Pointer to a \ref libx52_device *
+ *
+ * @returns \ref libx52_error_code indicating status
  */
-libx52_device * libx52_init(void);
+int libx52_init(libx52_device ** dev);
 
 /**
  * @brief Exit the library and free up any resources used
@@ -183,8 +216,8 @@ void libx52_exit(libx52_device *dev);
  *                      the code page of the X52 display.
  * @param[in]   length  Length of the text to display
  *
- * @returns 0 on success, \c -EINVAL if either \p x52 is invalid, or \p line is
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if either \p x52 is
- * outside the accepted range.
+ * invalid, or \p line is outside the accepted range.
  */
 int libx52_set_text(libx52_device *x52, uint8_t line, const char *text, uint8_t length);
 
@@ -204,10 +237,11 @@ int libx52_set_text(libx52_device *x52, uint8_t line, const char *text, uint8_t
  * @param[in]   led     LED identifier (refer \ref libx52_led_id)
  * @param[in]   state   State of the LED (refer \ref libx52_led_state)
  *
- * @returns 0 on success, \c -EINVAL if the \p x52 parameter is not valid, and
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if the \p x52
- * \c -ENOTSUP if the \p led and \p state combination is not a supported one.
+ * parameter is not valid, and \ref LIBX52_ERROR_NOT_SUPPORTED if the \p led
- * The API also returns \c -ENOTSUP if the probed joystick is not an X52 Pro,
+ * and \p state combination is not a supported one.  The API also returns \ref
- * but the non-Pro X52 variant.
+ * LIBX52_ERROR_NOT_SUPPORTED if the probed joystick is not an X52 Pro, but the
+ * non-Pro X52 variant.
  */
 int libx52_set_led_state(libx52_device *x52,
                          libx52_led_id led,
@@ -221,11 +255,11 @@ int libx52_set_led_state(libx52_device *x52,
  * whether the primary clock displays local time or GMT.
  *
  * If this function is called again within the same minute as calculated by
- * \c localtime(3) or \c gmtime(3), it will return \c -EAGAIN, as it does not
+ * \c localtime(3) or \c gmtime(3), it will return \ref LIBX52_ERROR_TRY_AGAIN,
- * require any updates to be written to the joystick. However, if the call
+ * as it does not require any updates to be written to the joystick. However,
- * changes the timezone from local time to GMT or vice-versa, then the function
+ * if the call changes the timezone from local time to GMT or vice-versa, then
- * will return 0, since it requires a write to the device to update the clock
+ * the function will return 0, since it requires a write to the device to
- * with the new timezone.
+ * update the clock with the new timezone.
  *
  * The secondary and tertiary clocks are driven off the primary clock and set
  * using \ref libx52_set_clock_timezone.
@@ -234,8 +268,8 @@ int libx52_set_led_state(libx52_device *x52,
  * @param[in]   time    Time value from \c time(3)
  * @param[in]   local   0 for GM time, non-zero for localtime
  *
- * @returns 0 on success, \c -EAGAIN if no change from previous time,
+ * @returns 0 on success, \ref LIBX52_ERROR_TRY_AGAIN if no change from previous
- *          \c -EINVAL if \p x52 is not valid.
+ *          time, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid.
  */
 int libx52_set_clock(libx52_device *x52, time_t time, int local);
 
@@ -247,7 +281,7 @@ int libx52_set_clock(libx52_device *x52, time_t time, int local);
  * However, for convenience, the X52 library calculates this offset internally
  * and only requires you to set the timezone as the number of minutes offset
  * from GMT. \p offset is limited to +/- 1440 minutes, and any offset outside
- * this range will result in a return value of \c -EDOM
+ * this range will result in a return value of \ref LIBX52_ERROR_OUT_OF_RANGE
  *
  * @param[in]   x52     Pointer to the device
  * @param[in]   clock   \ref libx52_clock_id, cannot be \ref
@@ -255,9 +289,9 @@ int libx52_set_clock(libx52_device *x52, time_t time, int local);
  * @param[in]   offset  Offset in minutes from GMT (east is positive, west
  *                      is negative)
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is invalid, \c -ENOTSUP if
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is invalid,
- * \p clock is \ref LIBX52_CLOCK_1, \c -EDOM if \p offset is more than +/-
+ * \ref LIBX52_ERROR_NOT_SUPPORTED if \p clock is \ref LIBX52_CLOCK_1, \ref
- * 24 hours.
+ * LIBX52_ERROR_OUT_OF_RANGE if \p offset is more than +/- 24 hours.
  */
 int libx52_set_clock_timezone(libx52_device *x52,
                               libx52_clock_id clock,
@@ -278,8 +312,8 @@ int libx52_set_clock_timezone(libx52_device *x52,
  * @param[in]   clock   \ref libx52_clock_id
  * @param[in]   format  \ref libx52_clock_format
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid, or if either of
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid,
- * \p clock or \p format are outside their respective ranges.
+ * or if either of \p clock or \p format are outside their respective ranges.
  */
 int libx52_set_clock_format(libx52_device *x52,
                             libx52_clock_id clock,
@@ -296,7 +330,7 @@ int libx52_set_clock_format(libx52_device *x52,
  * @param[in]   hour    Hour to display
  * @param[in]   minute  Minute to display
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid
  */
 int libx52_set_time(libx52_device *x52, uint8_t hour, uint8_t minute);
 
@@ -311,7 +345,7 @@ int libx52_set_time(libx52_device *x52, uint8_t hour, uint8_t minute);
  * @param[in]   mm      Month to display
  * @param[in]   yy      Year to display
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid
  */
 int libx52_set_date(libx52_device *x52, uint8_t dd, uint8_t mm, uint8_t yy);
 
@@ -323,7 +357,7 @@ int libx52_set_date(libx52_device *x52, uint8_t dd, uint8_t mm, uint8_t yy);
  * @param[in]   x52     Pointer to the device
  * @param[in]   format  \ref libx52_date_format
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid
  */
 int libx52_set_date_format(libx52_device *x52, libx52_date_format format);
 
@@ -339,7 +373,7 @@ int libx52_set_date_format(libx52_device *x52, libx52_date_format format);
  * @param[in]   mfd     0 for LED brightness, 1 for MFD brightness
  * @param[in]   brightness  Brightness level to set
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid.
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid.
  */
 int libx52_set_brightness(libx52_device *x52, uint8_t mfd, uint16_t brightness);
 
@@ -352,7 +386,7 @@ int libx52_set_brightness(libx52_device *x52, uint8_t mfd, uint16_t brightness);
  * @param[in]   x52     Pointer to the device
  * @param[in]   state   0 for off, 1 for on
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid
  */
 int libx52_set_shift(libx52_device *x52, uint8_t state);
 
@@ -364,7 +398,7 @@ int libx52_set_shift(libx52_device *x52, uint8_t state);
  * @param[in]   x52     Pointer to the device
  * @param[in]   state   0 for off, 1 for on
  *
- * @returns 0 on success, \c -EINVAL if \p x52 is not valid
+ * @returns 0 on success, \ref LIBX52_ERROR_INVALID_PARAM if \p x52 is not valid
  */
 int libx52_set_blink(libx52_device *x52, uint8_t state);
 
@@ -377,7 +411,7 @@ int libx52_set_blink(libx52_device *x52, uint8_t state);
  *
  * @param[in]   x52     Pointer to the device
  *
- * @returns 0 on success, non-zero error number on failure
+ * @returns 0 on success, \ref LIBX52_ERROR_USB_FAILURE on failure
  */
 int libx52_update(libx52_device *x52);
 
@@ -394,7 +428,7 @@ int libx52_update(libx52_device *x52);
  * @param[in]   index   wIndex in the USB packet
  * @param[in]   value   wValue in the USB packet
  *
- * @returns 0 on success, non-zero error number on failure
+ * @returns 0 on success, \ref LIBX52_ERROR_USB_FAILURE on failure
  */
 int libx52_vendor_command(libx52_device *x52, uint16_t index, uint16_t value);
 

lib/libx52/x52_control.c

@@ -30,12 +30,16 @@ int libx52_vendor_command(libx52_device *x52, uint16_t index, uint16_t value)
             LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE | LIBUSB_ENDPOINT_OUT,
             X52_VENDOR_REQUEST, value, index, NULL, 0, 5000);
 
-        if (rc == 0) {
+        if (rc == LIBUSB_SUCCESS) {
             break;
         }
     }
     
-    return rc;
+    if (rc == LIBUSB_SUCCESS) {
+        return LIBX52_SUCCESS;
+    } else {
+        return LIBX52_ERROR_USB_FAILURE;
+    }
 }
 
 static int libx52_write_line(libx52_device *x52, uint8_t line_index)
@@ -97,11 +101,11 @@ static int libx52_write_date(libx52_device *x52)
         break;
 
     default:
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     rc = libx52_vendor_command(x52, X52_DATE_DDMM, value1);
-    if (rc == 0) {
+    if (rc == LIBX52_SUCCESS) {
         rc = libx52_vendor_command(x52, X52_DATE_YEAR, value2);
     }
 
@@ -168,7 +172,7 @@ int libx52_update(libx52_device *x52)
     unsigned int i;
     uint32_t update_mask;
     uint16_t value;
-    int rc = 0;
+    int rc = LIBX52_SUCCESS;
 
     /* Save the update mask */
     update_mask = x52->update_mask;
@@ -221,7 +225,8 @@ int libx52_update(libx52_device *x52)
                 break;
 
             case X52_BIT_POV_BLINK:
-                value = tst_bit(&x52->led_mask, X52_BIT_POV_BLINK) ? X52_BLINK_ON : X52_BLINK_OFF;
+                value = tst_bit(&x52->led_mask, X52_BIT_POV_BLINK)
+                        ? X52_BLINK_ON : X52_BLINK_OFF;
                 rc = libx52_vendor_command(x52, X52_BLINK_INDICATOR, value);
                 break;
 
@@ -253,11 +258,11 @@ int libx52_update(libx52_device *x52)
 
             default:
                 /* Ignore any spurious bits */
-                rc = 0;
+                rc = LIBX52_SUCCESS;
                 break;
             }
 
-            if (rc == 0) {
+            if (rc == LIBX52_SUCCESS) {
                 clr_bit(&update_mask, i);
             } else {
                 /* Last transfer failed - reset the update mask */

lib/libx52/x52_core.c

@@ -45,7 +45,7 @@ static int libx52_device_is_x52pro(uint16_t idProduct)
     return (idProduct == X52_PROD_X52PRO);
 }
 
-libx52_device* libx52_init(void)
+int libx52_init(libx52_device **dev)
 {
     int rc;
     ssize_t count;
@@ -56,20 +56,20 @@ libx52_device* libx52_init(void)
     struct libusb_device_descriptor desc;
     libx52_device *x52_dev;
 
+    /* Make sure that we have a valid return pointer */
+    if (dev == NULL) {
+        return LIBX52_ERROR_INVALID_PARAM;
+    }
+
     /* Allocate memory for the library's data structures */
     x52_dev = calloc(1, sizeof(libx52_device));
     if (!x52_dev) {
-        errno = ENOMEM;
+        return LIBX52_ERROR_OUT_OF_MEMORY;
-        return NULL;
     }
 
     rc = libusb_init(&(x52_dev->ctx));
     if (rc) {
-#if defined(__linux__)
+        rc = LIBX52_ERROR_INIT_FAILURE;
-        errno = ELIBACC;
-#else
-        errno = ENOENT;
-#endif
         goto err_recovery;
     }
     libusb_set_debug(x52_dev->ctx, LIBUSB_LOG_LEVEL_WARNING);
@@ -100,10 +100,12 @@ libx52_device* libx52_init(void)
         goto err_recovery;
     }
 
-    return x52_dev;
+    *dev = x52_dev;
+    return LIBX52_SUCCESS;
+
 err_recovery:
     free(x52_dev);
-    return NULL;
+    return rc;
 }
 
 void libx52_exit(libx52_device *dev)

lib/libx52/x52_date_time.c

@@ -31,7 +31,7 @@ int libx52_set_clock(libx52_device *x52, time_t time, int local)
     int update_required = 0;
 
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (local) {
@@ -78,26 +78,26 @@ int libx52_set_clock(libx52_device *x52, time_t time, int local)
 
     /* Save the timezone */
     x52->timezone[LIBX52_CLOCK_1] = local_tz;
-    return (update_required ? 0 : -EAGAIN);
+    return (update_required ? LIBX52_SUCCESS : LIBX52_ERROR_TRY_AGAIN);
 }
 
 int libx52_set_time(libx52_device *x52, uint8_t hour, uint8_t minute)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     x52->time_hour = hour;
     x52->time_minute = minute;
     set_bit(&x52->update_mask, X52_BIT_MFD_TIME);
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_date(libx52_device *x52, uint8_t dd, uint8_t mm, uint8_t yy)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     x52->date_day = dd;
@@ -105,18 +105,18 @@ int libx52_set_date(libx52_device *x52, uint8_t dd, uint8_t mm, uint8_t yy)
     x52->date_year = yy;
     set_bit(&x52->update_mask, X52_BIT_MFD_DATE);
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_clock_timezone(libx52_device *x52, libx52_clock_id clock, int offset)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     /* Limit offset to +/- 24 hours */
     if (offset < -1440 || offset > 1440) {
-        return -EDOM;
+        return LIBX52_ERROR_OUT_OF_RANGE;
     }
 
     switch (clock) {
@@ -131,10 +131,10 @@ int libx52_set_clock_timezone(libx52_device *x52, libx52_clock_id clock, int off
         break;
 
     default:
-        return -ENOTSUP;
+        return LIBX52_ERROR_NOT_SUPPORTED;
     }
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_clock_format(libx52_device *x52,
@@ -142,13 +142,13 @@ int libx52_set_clock_format(libx52_device *x52,
                             libx52_clock_format format)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if ((format != LIBX52_CLOCK_FORMAT_12HR) &&
         (format != LIBX52_CLOCK_FORMAT_24HR)) {
 
-       return -EINVAL;
+       return LIBX52_ERROR_INVALID_PARAM;
     }
 
     switch (clock) {
@@ -165,20 +165,20 @@ int libx52_set_clock_format(libx52_device *x52,
         break;
 
     default:
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     x52->time_format[clock] = format;
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_date_format(libx52_device *x52, libx52_date_format format)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     x52->date_format = format;
     set_bit(&x52->update_mask, X52_BIT_MFD_DATE);
-    return 0;
+    return LIBX52_SUCCESS;
 }

lib/libx52/x52_mfd_led.c

@@ -20,11 +20,11 @@
 int libx52_set_text(libx52_device *x52, uint8_t line, const char *text, uint8_t length)
 {
     if (!x52 || !text) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (line > 2) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (length > X52_MFD_LINE_SIZE) {
@@ -36,13 +36,13 @@ int libx52_set_text(libx52_device *x52, uint8_t line, const char *text, uint8_t
     x52->line[line].length = length;
     set_bit(&x52->update_mask, X52_BIT_MFD_LINE1 + line);
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 static int x52pro_set_led_state(libx52_device *x52, libx52_led_id led, libx52_led_state state)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     switch (led) {
@@ -56,7 +56,7 @@ static int x52pro_set_led_state(libx52_device *x52, libx52_led_id led, libx52_le
             set_bit(&x52->update_mask, led);
         } else {
             /* Colors not supported */
-            return -ENOTSUP;
+            return LIBX52_ERROR_NOT_SUPPORTED;
         }
         break;
 
@@ -88,7 +88,7 @@ static int x52pro_set_led_state(libx52_device *x52, libx52_led_id led, libx52_le
 
         default:
             /* Cannot set the LED to "ON" */
-            return -ENOTSUP;
+            return LIBX52_ERROR_NOT_SUPPORTED;
         }
 
         /* Set the update mask bits */
@@ -97,13 +97,13 @@ static int x52pro_set_led_state(libx52_device *x52, libx52_led_id led, libx52_le
         break;
     }
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_led_state(libx52_device *x52, libx52_led_id led, libx52_led_state state)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (tst_bit(&x52->flags, X52_FLAG_IS_PRO)) {
@@ -114,13 +114,13 @@ int libx52_set_led_state(libx52_device *x52, libx52_led_id led, libx52_led_state
      * For now, we only support setting the LEDs on the X52 Pro model.
      * Calling this API on a non-Pro model will return a not supported error.
      */
-    return -ENOTSUP;
+    return LIBX52_ERROR_NOT_SUPPORTED;
 }
 
 int libx52_set_brightness(libx52_device *x52, uint8_t mfd, uint16_t brightness)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (mfd) {
@@ -131,13 +131,13 @@ int libx52_set_brightness(libx52_device *x52, uint8_t mfd, uint16_t brightness)
         set_bit(&x52->update_mask, X52_BIT_BRI_LED);
     }
 
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_shift(libx52_device *x52, uint8_t state)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (state) {
@@ -147,13 +147,13 @@ int libx52_set_shift(libx52_device *x52, uint8_t state)
     }
 
     set_bit(&x52->update_mask, X52_BIT_SHIFT);
-    return 0;
+    return LIBX52_SUCCESS;
 }
 
 int libx52_set_blink(libx52_device *x52, uint8_t state)
 {
     if (!x52) {
-        return -EINVAL;
+        return LIBX52_ERROR_INVALID_PARAM;
     }
 
     if (state) {
@@ -163,5 +163,5 @@ int libx52_set_blink(libx52_device *x52, uint8_t state)
     }
 
     set_bit(&x52->update_mask, X52_BIT_POV_BLINK);
-    return 0;
+    return LIBX52_SUCCESS;
 }

utils/cli/x52_cli.c

@@ -442,9 +442,9 @@ int main(int argc, char **argv)
     }
 
     /* Lookup the X52 device */
-    x52 = libx52_init();
+    rc = libx52_init(&x52);
 
-    if (!x52) {
+    if (rc != LIBX52_SUCCESS) {
         fprintf(stderr, "Unable to find X52 joystick!\n");
         return 1;
     }

utils/test/x52_test.c

@@ -109,8 +109,8 @@ static int run_tests(int test_set)
 
     getc(stdin);
 
-    dev = libx52_init();
+    rc = libx52_init(&dev);
-    if (dev == NULL) {
+    if (rc != LIBX52_SUCCESS) {
         fprintf(stderr, "Unable to connect to X52 Pro Joystick!\n");
         return 1;
     }