keyboard: add haptic feedback

buffyboard/buffyboard.conf

@@ -1,3 +1,6 @@
+[keyboard]
+haptic_feedback=true
+
 [theme]
 default=breezy-light
 

buffyboard/config.c

@@ -40,7 +40,13 @@ static int parsing_handler(void* user_data, const char* section, const char* key
 static int parsing_handler(void* user_data, const char* section, const char* key, const char* value) {
     bb_config_opts *opts = (bb_config_opts *)user_data;
 
-    if (strcmp(section, "theme") == 0) {
+    if (strcmp(section, "keyboard") == 0) {
+        if (strcmp(key, "haptic_feedback") == 0) {
+            if (bbx_config_parse_bool(value, &(opts->keyboard.haptic_feedback))) {
+                return 1;
+            }
+        }
+    } else if (strcmp(section, "theme") == 0) {
         if (strcmp(key, "default") == 0) {
             bbx_themes_theme_id_t id = bbx_themes_find_theme_with_name(value);
             if (id != BBX_THEMES_THEME_NONE) {
@@ -80,6 +86,7 @@ static int parsing_handler(void* user_data, const char* section, const char* key
  */
 
 void bb_config_init_opts(bb_config_opts *opts) {
+    opts->keyboard.haptic_feedback = true;
     opts->theme.default_id = BBX_THEMES_THEME_BREEZY_DARK;
     opts->input.pointer = true;
     opts->input.touchscreen = true;

buffyboard/config.h

@@ -11,6 +11,14 @@
 
 #include "sq2lv_layouts.h"
 
+/**
+ * Options related to the keyboard
+ */
+typedef struct {
+    /* If true, vibrate on key presses */
+    bool haptic_feedback;
+} bb_config_opts_keyboard;
+
 /**
  * Options related to the theme
  */
@@ -43,6 +51,8 @@ typedef struct {
  * Options parsed from config file(s)
  */
 typedef struct {
+    /* Options related to the keyboard */
+    bb_config_opts_keyboard keyboard;
     /* Options related to the theme */
     bb_config_opts_theme theme;
     /* Options related to input devices */

buffyboard/main.c

@@ -12,6 +12,7 @@
 
 #include "lvgl/lvgl.h"
 
+#include "../shared/force_feedback.h"
 #include "../shared/indev.h"
 #include "../shared/log.h"
 #include "../shared/theme.h"
@@ -93,6 +94,8 @@ static void keyboard_value_changed_cb(lv_event_t *event) {
         return;
     }
 
+    bbx_force_feedback_play();
+
     if (sq2lv_is_layer_switcher(kb, btn_id)) {
         pop_checked_modifier_keys();
         sq2lv_switch_layer(kb, btn_id);
@@ -296,7 +299,8 @@ int main(int argc, char *argv[]) {
     /* Attach input devices and start monitoring for new ones */
     struct bbx_indev_opts input_config = {
         .pointer = conf_opts.input.pointer,
-        .touchscreen = conf_opts.input.touchscreen
+        .touchscreen = conf_opts.input.touchscreen,
+        .force_feedback = conf_opts.keyboard.haptic_feedback
     };
     if (bbx_indev_init(fd_epoll, &input_config) == 0)
         return EXIT_FAILURE;

f0rmz/config.c

@@ -59,6 +59,10 @@ static int parsing_handler(void* user_data, const char* section, const char* key
             if (bbx_config_parse_bool(value, &(opts->keyboard.popovers))) {
                 return 1;
             }
+        } else if (strcmp(key, "haptic_feedback") == 0) {
+            if (bbx_config_parse_bool(value, &(opts->keyboard.haptic_feedback))) {
+                return 1;
+            }
         }
     } else if (strcmp(section, "theme") == 0) {
         if (strcmp(key, "default") == 0) {
@@ -190,6 +194,7 @@ void f0_config_init_opts(f0_config_opts *opts) {
     opts->keyboard.autohide = true;
     opts->keyboard.layout_id = SQ2LV_LAYOUT_US;
     opts->keyboard.popovers = true;
+    opts->keyboard.haptic_feedback = true;
     opts->textarea.obscured = true;
     opts->textarea.bullet = LV_SYMBOL_BULLET;
     opts->input.keyboard = true;

f0rmz/config.h

@@ -33,6 +33,8 @@ typedef struct {
     sq2lv_layout_id_t layout_id;
     /* If true, display key popovers on press */
     bool popovers;
+    /* If true, vibrate on key presses */
+    bool haptic_feedback;
 } f0_config_opts_keyboard;
 
 /**

f0rmz/main.c

@@ -8,6 +8,7 @@
 
 #include "../shared/backends.h"
 #include "../shared/display.h"
+#include "../shared/force_feedback.h"
 #include "../shared/header.h"
 #include "../shared/indev.h"
 #include "../shared/keyboard.h"
@@ -37,19 +38,19 @@
 f0_cli_opts cli_opts;
 f0_config_opts conf_opts;
 
-bool is_alternate_theme = false;
+static bool is_alternate_theme = false;
-bool is_keyboard_hidden = false;
+static bool is_keyboard_hidden = false;
 
 static char **field_values = NULL;
 
-int current_field_index = 0;
+static int current_field_index = 0;
 
-lv_obj_t *form_container = NULL;
+static lv_obj_t *form_container = NULL;
-lv_obj_t *form_textarea = NULL;
+static lv_obj_t *form_textarea = NULL;
-lv_obj_t *keyboard = NULL;
+static lv_obj_t *keyboard = NULL;
 
-int32_t content_height_with_kb;
+static int32_t content_height_with_kb;
-int32_t content_height_without_kb;
+static int32_t content_height_without_kb;
 
 /**
  * Static prototypes
@@ -265,7 +266,7 @@ static void exit_failure();
  * Static functions
  */
 
- static void intro_key_cb(lv_event_t *event) {
+static void intro_key_cb(lv_event_t *event) {
     uint32_t key = lv_indev_get_key(lv_indev_active());
     if (key == LV_KEY_ENTER) {
         get_started_btn_clicked_cb(event);
@@ -409,6 +410,8 @@ static void keyboard_value_changed_cb(lv_event_t *event) {
         return;
     }
 
+    bbx_force_feedback_play();
+
     if (sq2lv_is_layer_switcher(kb, btn_id)) {
         sq2lv_switch_layer(kb, btn_id);
         return;
@@ -889,7 +892,8 @@ int main(int argc, char *argv[]) {
         .keymap = &conf_opts.hw_keyboard,
         .keyboard = conf_opts.input.keyboard,
         .pointer = conf_opts.input.pointer,
-        .touchscreen = conf_opts.input.touchscreen
+        .touchscreen = conf_opts.input.touchscreen,
+        .force_feedback = conf_opts.keyboard.haptic_feedback
     };
     if (bbx_indev_init(fd_epoll, &input_config) == 0)
         exit_failure();

man/buffyboard.1.scd

@@ -54,7 +54,7 @@ result.
 
 # NOTES
 
-Some terminal commands, like _clear_ or _setfont_, can erase the keyboard or brake the layout of the terminal. In this case you should send a signal to Buffyboard or switch to another terminal to update the screen:
+Some terminal commands, like _clear_ or _setfont_, can erase the keyboard or break the layout of the terminal. In this case you should send a signal to Buffyboard or switch to another terminal to update the screen:
 
 ```
 setfont solar24x32;/usr/bin/kill -s SIGUSR1 buffyboard

man/buffyboard.conf.5.scd

@@ -25,6 +25,11 @@ for and, if found, merged in the following order:
 
 # OPTIONS
 
+## Keyboard
+*haptic_feedback* = <true|false>
+	Enable or disable vibrations when pressing keys.
+	Default: true.
+
 ## Theme
 *default* = <adwaita-light|adwaita-dark|breezy-light|breezy-dark|nord-light|nord-dark|pmos-light|pmos-dark>
 	Selects the default theme on boot. Can be changed at runtime to the

man/unl0kr.conf.5.scd

@@ -48,7 +48,11 @@ for and, if found, merged in the following order:
 
 *popovers* = <true|false>
 	Enable or disable key press popovers showing the selected key.
-	default: true.
+	Default: true.
+
+*haptic_feedback* = <true|false>
+	Enable or disable vibrations when pressing keys.
+	Default: true.
 
 ## Textarea
 *obscured* = <true|false>

meson.build

@@ -26,6 +26,7 @@ shared_sources = files(
     'shared/fonts/font_32.c',
     'shared/cli_common.c',
     'shared/config.c',
+    'shared/force_feedback.c',
     'shared/indev.c',
     'shared/log.c',
     'shared/theme.c',

shared/force_feedback.c

@@ -0,0 +1,109 @@
+/**
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "force_feedback.h"
+
+#include "log.h"
+
+#include <linux/input.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <libudev.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#define bit_is_set(array, bit)  ((array[bit / 8] >> bit % 8) & 0x01)
+
+/**
+ * Static variables
+ */
+
+static int fd = -1;
+static struct input_event ff_event = {
+    .type = EV_FF,
+    .code = 0,
+    .value = 1
+};
+
+/**
+ * Public functions
+ */
+
+void bbx_force_feedback_connect(struct udev_device* device) {
+    if (fd >= 0)
+        return;
+
+    const char* node = udev_device_get_devnode(device);
+
+    int fd_event = open(node, O_RDWR);
+    if (fd_event < 0) {
+        bbx_log(BBX_LOG_LEVEL_ERROR, "Can't open %s", node);
+        return;
+    }
+
+    int n_effects;
+    if (ioctl(fd_event, EVIOCGEFFECTS, &n_effects) == -1 || n_effects == 0) {
+        close(fd_event);
+        return;
+    }
+
+    bbx_log(BBX_LOG_LEVEL_VERBOSE, "Found a force feedback device: %s", node);
+
+    uint8_t features[(FF_CNT + 7) / 8];
+    if (ioctl(fd_event, EVIOCGBIT(EV_FF, sizeof(features)), features) == -1) {
+        bbx_log(BBX_LOG_LEVEL_ERROR, "Can't request features of %s", node);
+        close(fd_event);
+        return;
+    }
+
+    if (!bit_is_set(features, FF_RUMBLE)) {
+        bbx_log(BBX_LOG_LEVEL_VERBOSE, "%s does not support FF_RUMBLE", node);
+        close(fd_event);
+        return;
+    }
+
+    struct ff_effect effect = {
+        .type = FF_RUMBLE,
+	.id = -1,
+	.direction = 0x0000,
+	.trigger.button = 0,
+	.trigger.interval = 0,
+	.replay.length = 50,
+	.replay.delay = 0,
+	.u.rumble.strong_magnitude = 0xC000,
+	.u.rumble.weak_magnitude = 0xC000
+    };
+
+    if (ioctl(fd_event, EVIOCSFF, &effect) == -1) {
+        bbx_log(BBX_LOG_LEVEL_ERROR, "Can't upload the effect");
+        close(fd_event);
+        return;
+    }
+
+    ff_event.code = effect.id;
+
+    if (bit_is_set(features, FF_GAIN)) {
+        struct input_event gain = {
+            .type = EV_FF,
+            .code = FF_GAIN,
+            .value = 0xFFFF
+        };
+
+        if (write(fd_event, &gain, sizeof(gain)) != sizeof(gain))
+            bbx_log(BBX_LOG_LEVEL_WARNING, "Can't set the gain");
+    }
+
+    fd = fd_event;
+}
+
+void bbx_force_feedback_play() {
+    if (fd < 0)
+        return;
+
+    if (write(fd, &ff_event, sizeof(ff_event)) != sizeof(ff_event)) {
+        // Assume that the force feedback device was disconnected
+        close(fd);
+        fd = -1;
+    }
+}

shared/force_feedback.h

@@ -0,0 +1,20 @@
+/**
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#ifndef BBX_FORCE_FEEDBACK_H
+#define BBX_FORCE_FEEDBACK_H
+
+#include <libudev.h>
+
+/**
+ * Try to connect a force feedback device.
+ */
+void bbx_force_feedback_connect(struct udev_device* device);
+
+/**
+ * Play a force feedback effect.
+ */
+void bbx_force_feedback_play();
+
+#endif /* BBX_FORCE_FEEDBACK_H */

shared/indev.c

@@ -6,6 +6,7 @@
 #include "indev.h"
 
 #include "cursor/cursor.h"
+#include "force_feedback.h"
 #include "log.h"
 
 #include "lvgl/lvgl.h"
@@ -93,6 +94,7 @@ static struct {
 #endif
     uint8_t pointer : 1;
     uint8_t touchscreen : 1;
+    uint8_t force_feedback : 1;
 } options;
 
 /**
@@ -641,6 +643,12 @@ static void attach_input_device(struct udev_device* device) {
         break;
     }
 
+    /* A device can be a force feedback device and an input device independently,
+       so we check for both capabilities. */
+
+    if (options.force_feedback)
+        bbx_force_feedback_connect(device);
+
     struct libinput_device* dev = libinput_path_add_device(context_libinput, node);
     if (!dev) {
         bbx_log(BBX_LOG_LEVEL_WARNING, "libinput can't use %s", node);
@@ -795,6 +803,7 @@ uint8_t bbx_indev_init(int fd_epoll, const struct bbx_indev_opts* opts) {
 #endif
     options.pointer = opts->pointer;
     options.touchscreen = opts->touchscreen;
+    options.force_feedback = opts->force_feedback;
 
     attach_input_devices();
 

shared/indev.h

@@ -20,6 +20,7 @@ struct bbx_indev_opts {
 #endif
     uint8_t pointer : 1;
     uint8_t touchscreen : 1;
+    uint8_t force_feedback : 1;
 };
 
 #ifndef BBX_APP_BUFFYBOARD

unl0kr/config.c

@@ -71,6 +71,10 @@ static int parsing_handler(void* user_data, const char* section, const char* key
             if (bbx_config_parse_bool(value, &(opts->keyboard.popovers))) {
                 return 1;
             }
+        } else if (strcmp(key, "haptic_feedback") == 0) {
+            if (bbx_config_parse_bool(value, &(opts->keyboard.haptic_feedback))) {
+                return 1;
+            }
         }
     } else if (strcmp(section, "textarea") == 0) {
         if (strcmp(key, "obscured") == 0) {
@@ -161,6 +165,7 @@ void ul_config_init_opts(ul_config_opts *opts) {
     opts->keyboard.autohide = true;
     opts->keyboard.layout_id = SQ2LV_LAYOUT_US;
     opts->keyboard.popovers = true;
+    opts->keyboard.haptic_feedback = true;
     opts->textarea.obscured = true;
     opts->textarea.bullet = LV_SYMBOL_BULLET;
     opts->theme.default_id = BBX_THEMES_THEME_BREEZY_DARK;

unl0kr/config.h

@@ -39,6 +39,8 @@ typedef struct {
     sq2lv_layout_id_t layout_id;
     /* If true, display key popovers on press */
     bool popovers;
+    /* If true, vibrate on key presses */
+    bool haptic_feedback;
 } ul_config_opts_keyboard;
 
 /**

unl0kr/main.c

@@ -10,6 +10,7 @@
 
 #include "../shared/backends.h"
 #include "../shared/display.h"
+#include "../shared/force_feedback.h"
 #include "../shared/header.h"
 #include "../shared/indev.h"
 #include "../shared/keyboard.h"
@@ -334,6 +335,8 @@ static void keyboard_value_changed_cb(lv_event_t *event) {
         return;
     }
 
+    bbx_force_feedback_play();
+
     if (sq2lv_is_layer_switcher(kb, btn_id)) {
         sq2lv_switch_layer(kb, btn_id);
         return;
@@ -447,7 +450,8 @@ int main(int argc, char *argv[]) {
         .keymap = &conf_opts.hw_keyboard,
         .keyboard = conf_opts.input.keyboard,
         .pointer = conf_opts.input.pointer,
-        .touchscreen = conf_opts.input.touchscreen
+        .touchscreen = conf_opts.input.touchscreen,
+        .force_feedback = conf_opts.keyboard.haptic_feedback
     };
     if (bbx_indev_init(fd_epoll, &input_config) == 0)
         exit_failure();

unl0kr/unl0kr.conf

@@ -7,6 +7,7 @@ animations=true
 autohide=false
 layout=us
 popovers=true
+haptic_feedback=true
 
 [textarea]
 obscured=true