From 1c78b0800759174abe1bac01ce5b9cd788a6a372 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Wed, 10 Nov 2021 20:02:25 -0800
Subject: [PATCH] Added support for /dev/input/js* on Linux
Added the hint SDL_HINT_LINUX_JOYSTICK_CLASSIC to control whether /dev/input/js* or /dev/input/event* are used as joystick devices
Added the hint SDL_HINT_JOYSTICK_DEVICE to allow the user to specify devices t
hat will be opened in addition to the normal joystick detection
Fixes https://github.com/libsdl-org/SDL/issues/1314
Fixes https://github.com/libsdl-org/SDL/issues/1727
Fixes https://github.com/libsdl-org/SDL/issues/1981
Closes https://github.com/libsdl-org/SDL/pull/4727
---
WhatsNew.txt | 4 +
include/SDL_hints.h | 18 ++
src/joystick/linux/SDL_sysjoystick.c | 246 +++++++++++++++++++------
src/joystick/linux/SDL_sysjoystick_c.h | 5 +
4 files changed, 213 insertions(+), 60 deletions(-)
diff --git a/WhatsNew.txt b/WhatsNew.txt
index 4822970b30..e6076c552c 100644
--- a/WhatsNew.txt
+++ b/WhatsNew.txt
@@ -5,6 +5,10 @@ This is a list of major changes in SDL's version history.
2.0.18:
---------------------------------------------------------------------------
+Linux:
+* Added the hint SDL_HINT_LINUX_JOYSTICK_CLASSIC to control whether /dev/input/js* or /dev/input/event* are used as joystick devices
+* Added the hint SDL_HINT_JOYSTICK_DEVICE to allow the user to specify devices that will be opened in addition to the normal joystick detection
+
Android:
* Added support for audio output and capture using AAudio on Android 8.1 and newer
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index db286a24ca..d7782591b2 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -816,6 +816,24 @@ extern "C" {
*/
#define SDL_HINT_KMSDRM_REQUIRE_DRM_MASTER "SDL_KMSDRM_REQUIRE_DRM_MASTER"
+ /**
+ * \brief A comma separated list of devices to open as joysticks
+ *
+ * This variable is currently only used by the Linux joystick driver.
+ */
+#define SDL_HINT_JOYSTICK_DEVICE "SDL_JOYSTICK_DEVICE"
+
+ /**
+ * \brief A variable controlling whether to use the classic /dev/input/js* joystick interface or the newer /dev/input/event* joystick interface on Linux
+ *
+ * This variable can be set to the following values:
+ * "0" - Use /dev/input/event*
+ * "1" - Use /dev/input/js*
+ *
+ * By default the /dev/input/event* interfaces are used
+ */
+#define SDL_HINT_LINUX_JOYSTICK_CLASSIC "SDL_LINUX_JOYSTICK_CLASSIC"
+
/**
* \brief A variable controlling whether joysticks on Linux adhere to their HID-defined deadzones or return unfiltered values.
*
diff --git a/src/joystick/linux/SDL_sysjoystick.c b/src/joystick/linux/SDL_sysjoystick.c
index aef8e332e9..52859d576d 100644
--- a/src/joystick/linux/SDL_sysjoystick.c
+++ b/src/joystick/linux/SDL_sysjoystick.c
@@ -85,6 +85,7 @@ typedef enum
static EnumerationMethod enumeration_method = ENUMERATION_UNSET;
+static SDL_bool IsJoystickDeviceNode(const char *node);
static int MaybeAddDevice(const char *path);
static int MaybeRemoveDevice(const char *path);
@@ -105,6 +106,7 @@ typedef struct SDL_joylist_item
SDL_GamepadMapping *mapping;
} SDL_joylist_item;
+static SDL_bool SDL_classic_joysticks = SDL_TRUE;
static SDL_joylist_item *SDL_joylist = NULL;
static SDL_joylist_item *SDL_joylist_tail = NULL;
static int numjoysticks = 0;
@@ -183,17 +185,22 @@ IsJoystick(int fd, char **name_return, SDL_JoystickGUID *guid)
char *name;
char product_string[128];
- /* When udev is enabled we only get joystick devices here, so there's no need to test them */
- if (enumeration_method != ENUMERATION_LIBUDEV && !GuessIsJoystick(fd)) {
- return 0;
- }
+ if (ioctl(fd, JSIOCGNAME(sizeof(product_string)), product_string) >= 0) {
+ inpid.vendor = 0;
+ inpid.product = 0;
+ } else {
+ /* When udev is enabled we only get joystick devices here, so there's no need to test them */
+ if (enumeration_method != ENUMERATION_LIBUDEV && !GuessIsJoystick(fd)) {
+ return 0;
+ }
- if (ioctl(fd, EVIOCGID, &inpid) < 0) {
- return 0;
- }
+ if (ioctl(fd, EVIOCGID, &inpid) < 0) {
+ return 0;
+ }
- if (ioctl(fd, EVIOCGNAME(sizeof(product_string)), product_string) < 0) {
- return 0;
+ if (ioctl(fd, EVIOCGNAME(sizeof(product_string)), product_string) < 0) {
+ return 0;
+ }
}
name = SDL_CreateJoystickName(inpid.vendor, inpid.product, NULL, product_string);
@@ -213,7 +220,7 @@ IsJoystick(int fd, char **name_return, SDL_JoystickGUID *guid)
FixupDeviceInfoForMapping(fd, &inpid);
#ifdef DEBUG_JOYSTICK
- printf("Joystick: %s, bustype = %d, vendor = 0x%.4x, product = 0x%.4x, version = %d\n", name, inpid.bustype, inpid.vendor, inpid.product, inpid.version);
+ SDL_Log("Joystick: %s, bustype = %d, vendor = 0x%.4x, product = 0x%.4x, version = %d\n", name, inpid.bustype, inpid.vendor, inpid.product, inpid.version);
#endif
SDL_memset(guid->data, 0, sizeof(guid->data));
@@ -254,6 +261,9 @@ static void joystick_udev_callback(SDL_UDEV_deviceevent udev_type, int udev_clas
if (!(udev_class & SDL_UDEV_DEVICE_JOYSTICK)) {
return;
}
+ if (SDL_classic_joysticks && !IsJoystickDeviceNode(devpath)) {
+ return;
+ }
MaybeAddDevice(devpath);
break;
@@ -308,7 +318,7 @@ MaybeAddDevice(const char *path)
}
#ifdef DEBUG_INPUT_EVENTS
- printf("Checking %s\n", path);
+ SDL_Log("Checking %s\n", path);
#endif
isstick = IsJoystick(fd, &name, &guid);
@@ -507,6 +517,20 @@ StrIsInteger(const char *string)
return 1;
}
+static SDL_bool
+IsJoystickDeviceNode(const char *node)
+{
+ const char *last_slash = SDL_strrchr(node, '/');
+ if (last_slash) {
+ node = last_slash + 1;
+ }
+ if (SDL_classic_joysticks) {
+ return (StrHasPrefix(node, "js") && StrIsInteger(node + 2));
+ } else {
+ return (StrHasPrefix(node, "event") && StrIsInteger(node + 5));
+ }
+}
+
static void
LINUX_InotifyJoystickDetect(void)
{
@@ -519,6 +543,7 @@ LINUX_InotifyJoystickDetect(void)
ssize_t bytes;
size_t remain = 0;
size_t len;
+ char path[PATH_MAX];
bytes = read(inotify_fd, &buf, sizeof (buf));
@@ -528,10 +553,7 @@ LINUX_InotifyJoystickDetect(void)
while (remain > 0) {
if (buf.event.len > 0) {
- if (StrHasPrefix(buf.event.name, "event") &&
- StrIsInteger(buf.event.name + SDL_strlen ("event"))) {
- char path[PATH_MAX];
-
+ if (IsJoystickDeviceNode(buf.event.name)) {
SDL_snprintf(path, SDL_arraysize(path), "/dev/input/%s", buf.event.name);
if (buf.event.mask & (IN_CREATE | IN_MOVED_TO | IN_ATTRIB)) {
@@ -560,7 +582,7 @@ LINUX_InotifyJoystickDetect(void)
static int
filter_entries(const struct dirent *entry)
{
- return (SDL_strlen(entry->d_name) > 5 && SDL_strncmp(entry->d_name, "event", 5) == 0);
+ return IsJoystickDeviceNode(entry->d_name);
}
static int
sort_entries(const struct dirent **a, const struct dirent **b)
@@ -627,7 +649,9 @@ LINUX_JoystickDetect(void)
static int
LINUX_JoystickInit(void)
{
- const char *devices = SDL_GetHint("SDL_JOYSTICK_DEVICE");
+ const char *devices = SDL_GetHint(SDL_HINT_JOYSTICK_DEVICE);
+
+ SDL_classic_joysticks = SDL_GetHintBoolean(SDL_HINT_LINUX_JOYSTICK_CLASSIC, SDL_FALSE);
#if SDL_USE_LIBUDEV
if (enumeration_method == ENUMERATION_UNSET) {
@@ -824,6 +848,7 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
unsigned long absbit[NBITS(ABS_MAX)] = { 0 };
unsigned long relbit[NBITS(REL_MAX)] = { 0 };
unsigned long ffbit[NBITS(FF_MAX)] = { 0 };
+ Uint8 key_pam_size, abs_pam_size;
SDL_bool use_deadzones = SDL_GetHintBoolean(SDL_HINT_LINUX_JOYSTICK_DEADZONES, SDL_FALSE);
/* See if this device uses the new unified event API */
@@ -835,7 +860,7 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
for (i = BTN_JOYSTICK; i < KEY_MAX; ++i) {
if (test_bit(i, keybit)) {
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick has button: 0x%x\n", i);
+ SDL_Log("Joystick has button: 0x%x\n", i);
#endif
joystick->hwdata->key_map[i] = joystick->nbuttons;
joystick->hwdata->has_key[i] = SDL_TRUE;
@@ -845,7 +870,7 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
for (i = 0; i < BTN_JOYSTICK; ++i) {
if (test_bit(i, keybit)) {
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick has button: 0x%x\n", i);
+ SDL_Log("Joystick has button: 0x%x\n", i);
#endif
joystick->hwdata->key_map[i] = joystick->nbuttons;
joystick->hwdata->has_key[i] = SDL_TRUE;
@@ -866,10 +891,10 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
continue;
}
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick has absolute axis: 0x%.2x\n", i);
- printf("Values = { %d, %d, %d, %d, %d }\n",
- absinfo.value, absinfo.minimum, absinfo.maximum,
- absinfo.fuzz, absinfo.flat);
+ SDL_Log("Joystick has absolute axis: 0x%.2x\n", i);
+ SDL_Log("Values = { %d, %d, %d, %d, %d }\n",
+ absinfo.value, absinfo.minimum, absinfo.maximum,
+ absinfo.fuzz, absinfo.flat);
#endif /* DEBUG_INPUT_EVENTS */
joystick->hwdata->abs_map[i] = joystick->naxes;
joystick->hwdata->has_abs[i] = SDL_TRUE;
@@ -906,10 +931,10 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
continue;
}
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick has hat %d\n", hat_index);
- printf("Values = { %d, %d, %d, %d, %d }\n",
- absinfo.value, absinfo.minimum, absinfo.maximum,
- absinfo.fuzz, absinfo.flat);
+ SDL_Log("Joystick has hat %d\n", hat_index);
+ SDL_Log("Values = { %d, %d, %d, %d, %d }\n",
+ absinfo.value, absinfo.minimum, absinfo.maximum,
+ absinfo.fuzz, absinfo.flat);
#endif /* DEBUG_INPUT_EVENTS */
joystick->hwdata->hats_indices[hat_index] = joystick->nhats++;
joystick->hwdata->has_hat[hat_index] = SDL_TRUE;
@@ -919,19 +944,75 @@ ConfigJoystick(SDL_Joystick *joystick, int fd)
++joystick->nballs;
}
- /* Allocate data to keep track of these thingamajigs */
- if (joystick->nhats > 0) {
- if (allocate_hatdata(joystick) < 0) {
- joystick->nhats = 0;
+ } else if ((ioctl(fd, JSIOCGBUTTONS, &key_pam_size, sizeof(key_pam_size)) >= 0) &&
+ (ioctl(fd, JSIOCGAXES, &abs_pam_size, sizeof(abs_pam_size)) >= 0)) {
+ size_t len;
+
+ joystick->hwdata->classic = SDL_TRUE;
+
+ len = (KEY_MAX - BTN_MISC + 1) * sizeof(*joystick->hwdata->key_pam);
+ joystick->hwdata->key_pam = (Uint16 *)SDL_calloc(1, len);
+ if (joystick->hwdata->key_pam) {
+ if (ioctl(fd, JSIOCGBTNMAP, joystick->hwdata->key_pam, len) < 0) {
+ SDL_free(joystick->hwdata->key_pam);
+ joystick->hwdata->key_pam = NULL;
+ key_pam_size = 0;
}
}
- if (joystick->nballs > 0) {
- if (allocate_balldata(joystick) < 0) {
- joystick->nballs = 0;
+ for (i = 0; i < key_pam_size; ++i) {
+ Uint16 code = joystick->hwdata->key_pam[i];
+#ifdef DEBUG_INPUT_EVENTS
+ SDL_Log("Joystick has button: 0x%x\n", code);
+#endif
+ joystick->hwdata->key_map[code] = joystick->nbuttons;
+ joystick->hwdata->has_key[code] = SDL_TRUE;
+ ++joystick->nbuttons;
+ }
+
+ len = ABS_CNT * sizeof(*joystick->hwdata->abs_pam);
+ joystick->hwdata->abs_pam = (Uint8 *)SDL_calloc(1, len);
+ if (joystick->hwdata->abs_pam) {
+ if (ioctl(fd, JSIOCGAXMAP, joystick->hwdata->abs_pam, len) < 0) {
+ SDL_free(joystick->hwdata->abs_pam);
+ joystick->hwdata->abs_pam = NULL;
+ abs_pam_size = 0;
+ }
+ }
+ for (i = 0; i < abs_pam_size; ++i) {
+ Uint8 code = joystick->hwdata->abs_pam[i];
+
+ if (code >= ABS_HAT0X && code <= ABS_HAT3Y) {
+ int hat_index = (code - ABS_HAT0X) / 2;
+ if (!joystick->hwdata->has_hat[hat_index]) {
+#ifdef DEBUG_INPUT_EVENTS
+ SDL_Log("Joystick has hat %d\n", hat_index);
+#endif
+ joystick->hwdata->hats_indices[hat_index] = joystick->nhats++;
+ joystick->hwdata->has_hat[hat_index] = SDL_TRUE;
+ }
+ } else {
+#ifdef DEBUG_INPUT_EVENTS
+ SDL_Log("Joystick has absolute axis: 0x%.2x\n", code);
+#endif
+ joystick->hwdata->abs_map[code] = joystick->naxes;
+ joystick->hwdata->has_abs[code] = SDL_TRUE;
+ ++joystick->naxes;
}
}
}
+ /* Allocate data to keep track of these thingamajigs */
+ if (joystick->nhats > 0) {
+ if (allocate_hatdata(joystick) < 0) {
+ joystick->nhats = 0;
+ }
+ }
+ if (joystick->nballs > 0) {
+ if (allocate_balldata(joystick) < 0) {
+ joystick->nballs = 0;
+ }
+ }
+
if (ioctl(fd, EVIOCGBIT(EV_FF, sizeof(ffbit)), ffbit) >= 0) {
if (test_bit(FF_RUMBLE, ffbit)) {
joystick->hwdata->ff_rumble = SDL_TRUE;
@@ -955,6 +1036,7 @@ PrepareJoystickHwdata(SDL_Joystick *joystick, SDL_joylist_item *item)
joystick->hwdata->guid = item->guid;
joystick->hwdata->effect.id = -1;
joystick->hwdata->m_bSteamController = item->m_bSteamController;
+ SDL_memset(joystick->hwdata->key_map, 0xFF, sizeof(joystick->hwdata->key_map));
SDL_memset(joystick->hwdata->abs_map, 0xFF, sizeof(joystick->hwdata->abs_map));
if (item->m_bSteamController) {
@@ -1098,7 +1180,7 @@ LINUX_JoystickSetSensorsEnabled(SDL_Joystick *joystick, SDL_bool enabled)
return SDL_Unsupported();
}
-static SDL_INLINE void
+static void
HandleHat(SDL_Joystick *stick, Uint8 hat, int axis, int value)
{
struct hwdata_hat *the_hat;
@@ -1123,14 +1205,14 @@ HandleHat(SDL_Joystick *stick, Uint8 hat, int axis, int value)
}
}
-static SDL_INLINE void
+static void
HandleBall(SDL_Joystick *stick, Uint8 ball, int axis, int value)
{
stick->hwdata->balls[ball].axis[axis] += value;
}
-static SDL_INLINE int
+static int
AxisCorrect(SDL_Joystick *joystick, int which, int value)
{
struct axis_correct *correct;
@@ -1164,7 +1246,7 @@ AxisCorrect(SDL_Joystick *joystick, int which, int value)
return value;
}
-static SDL_INLINE void
+static void
PollAllValues(SDL_Joystick *joystick)
{
struct input_absinfo absinfo;
@@ -1182,7 +1264,7 @@ PollAllValues(SDL_Joystick *joystick)
absinfo.value = AxisCorrect(joystick, i, absinfo.value);
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick : Re-read Axis %d (%d) val= %d\n",
+ SDL_Log("Joystick : Re-read Axis %d (%d) val= %d\n",
joystick->hwdata->abs_map[i], i, absinfo.value);
#endif
SDL_PrivateJoystickAxis(joystick,
@@ -1212,7 +1294,7 @@ PollAllValues(SDL_Joystick *joystick)
if (joystick->hwdata->has_key[i]) {
const Uint8 value = test_bit(i, keyinfo) ? SDL_PRESSED : SDL_RELEASED;
#ifdef DEBUG_INPUT_EVENTS
- printf("Joystick : Re-read Button %d (%d) val= %d\n",
+ SDL_Log("Joystick : Re-read Button %d (%d) val= %d\n",
joystick->hwdata->key_map[i], i, value);
#endif
SDL_PrivateJoystickButton(joystick,
@@ -1224,12 +1306,11 @@ PollAllValues(SDL_Joystick *joystick)
/* Joyballs are relative input, so there's no poll state. Events only! */
}
-static SDL_INLINE void
+static void
HandleInputEvents(SDL_Joystick *joystick)
{
struct input_event events[32];
- int i, len;
- int code;
+ int i, len, code;
if (joystick->hwdata->fresh) {
PollAllValues(joystick);
@@ -1268,13 +1349,10 @@ HandleInputEvents(SDL_Joystick *joystick)
HandleHat(joystick, joystick->hwdata->hats_indices[code / 2], code % 2, events[i].value);
break;
default:
- if (joystick->hwdata->abs_map[code] != 0xFF) {
- events[i].value =
- AxisCorrect(joystick, code, events[i].value);
- SDL_PrivateJoystickAxis(joystick,
- joystick->hwdata->abs_map[code],
- events[i].value);
- }
+ events[i].value = AxisCorrect(joystick, code, events[i].value);
+ SDL_PrivateJoystickAxis(joystick,
+ joystick->hwdata->abs_map[code],
+ events[i].value);
break;
}
break;
@@ -1293,7 +1371,7 @@ HandleInputEvents(SDL_Joystick *joystick)
switch (code) {
case SYN_DROPPED :
#ifdef DEBUG_INPUT_EVENTS
- printf("Event SYN_DROPPED detected\n");
+ SDL_Log("Event SYN_DROPPED detected\n");
#endif
joystick->hwdata->recovering_from_dropped = SDL_TRUE;
break;
@@ -1318,6 +1396,48 @@ HandleInputEvents(SDL_Joystick *joystick)
}
}
+static void
+HandleClassicEvents(SDL_Joystick *joystick)
+{
+ struct js_event events[32];
+ int i, len, code;
+
+ joystick->hwdata->fresh = SDL_FALSE;
+ while ((len = read(joystick->hwdata->fd, events, (sizeof events))) > 0) {
+ len /= sizeof(events[0]);
+ for (i = 0; i < len; ++i) {
+ switch (events[i].type) {
+ case JS_EVENT_BUTTON:
+ code = joystick->hwdata->key_pam[events[i].number];
+ SDL_PrivateJoystickButton(joystick,
+ joystick->hwdata->key_map[code],
+ events[i].value);
+ break;
+ case JS_EVENT_AXIS:
+ code = joystick->hwdata->abs_pam[events[i].number];
+ switch (code) {
+ case ABS_HAT0X:
+ case ABS_HAT0Y:
+ case ABS_HAT1X:
+ case ABS_HAT1Y:
+ case ABS_HAT2X:
+ case ABS_HAT2Y:
+ case ABS_HAT3X:
+ case ABS_HAT3Y:
+ code -= ABS_HAT0X;
+ HandleHat(joystick, joystick->hwdata->hats_indices[code / 2], code % 2, events[i].value);
+ break;
+ default:
+ SDL_PrivateJoystickAxis(joystick,
+ joystick->hwdata->abs_map[code],
+ events[i].value);
+ break;
+ }
+ }
+ }
+ }
+}
+
static void
LINUX_JoystickUpdate(SDL_Joystick *joystick)
{
@@ -1328,7 +1448,11 @@ LINUX_JoystickUpdate(SDL_Joystick *joystick)
return;
}
- HandleInputEvents(joystick);
+ if (joystick->hwdata->classic) {
+ HandleClassicEvents(joystick);
+ } else {
+ HandleInputEvents(joystick);
+ }
/* Deliver ball motion updates */
for (i = 0; i < joystick->nballs; ++i) {
@@ -1359,6 +1483,8 @@ LINUX_JoystickClose(SDL_Joystick *joystick)
if (joystick->hwdata->item) {
joystick->hwdata->item->hwdata = NULL;
}
+ SDL_free(joystick->hwdata->key_pam);
+ SDL_free(joystick->hwdata->abs_pam);
SDL_free(joystick->hwdata->hats);
SDL_free(joystick->hwdata->balls);
SDL_free(joystick->hwdata->fname);
@@ -1525,20 +1651,20 @@ LINUX_JoystickGetGamepadMapping(int device_index, SDL_GamepadMapping *out)
out->lefttrigger.target = hat | 0x4;
out->righttrigger.target = hat | 0x2;
} else {
- if (joystick->hwdata->has_key[BTN_TL2]) {
- out->lefttrigger.kind = EMappingKind_Button;
- out->lefttrigger.target = joystick->hwdata->key_map[BTN_TL2];
- } else if (joystick->hwdata->has_abs[ABS_Z]) {
+ if (joystick->hwdata->has_abs[ABS_Z]) {
out->lefttrigger.kind = EMappingKind_Axis;
out->lefttrigger.target = joystick->hwdata->abs_map[ABS_Z];
+ } else if (joystick->hwdata->has_key[BTN_TL2]) {
+ out->lefttrigger.kind = EMappingKind_Button;
+ out->lefttrigger.target = joystick->hwdata->key_map[BTN_TL2];
}
- if (joystick->hwdata->has_key[BTN_TR2]) {
- out->righttrigger.kind = EMappingKind_Button;
- out->righttrigger.target = joystick->hwdata->key_map[BTN_TR2];
- } else if (joystick->hwdata->has_abs[ABS_RZ]) {
+ if (joystick->hwdata->has_abs[ABS_RZ]) {
out->righttrigger.kind = EMappingKind_Axis;
out->righttrigger.target = joystick->hwdata->abs_map[ABS_RZ];
+ } else if (joystick->hwdata->has_key[BTN_TR2]) {
+ out->righttrigger.kind = EMappingKind_Button;
+ out->righttrigger.target = joystick->hwdata->key_map[BTN_TR2];
}
}
diff --git a/src/joystick/linux/SDL_sysjoystick_c.h b/src/joystick/linux/SDL_sysjoystick_c.h
index 898f183dd6..630e2f5c5b 100644
--- a/src/joystick/linux/SDL_sysjoystick_c.h
+++ b/src/joystick/linux/SDL_sysjoystick_c.h
@@ -56,6 +56,11 @@ struct joystick_hwdata
SDL_bool has_key[KEY_MAX];
SDL_bool has_abs[ABS_MAX];
+ /* Support for the classic joystick interface */
+ SDL_bool classic;
+ Uint16 *key_pam;
+ Uint8 *abs_pam;
+
struct axis_correct
{
SDL_bool use_deadzones;