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-rw-r--r--drivers/accessibility/speakup/fakekey.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/drivers/accessibility/speakup/fakekey.c b/drivers/accessibility/speakup/fakekey.c
new file mode 100644
index 000000000000..cd029968462f
--- /dev/null
+++ b/drivers/accessibility/speakup/fakekey.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* fakekey.c
+ * Functions for simulating keypresses.
+ *
+ * Copyright (C) 2010 the Speakup Team
+ */
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/preempt.h>
+#include <linux/percpu.h>
+#include <linux/input.h>
+
+#include "speakup.h"
+
+#define PRESSED 1
+#define RELEASED 0
+
+static DEFINE_PER_CPU(int, reporting_keystroke);
+
+static struct input_dev *virt_keyboard;
+
+int speakup_add_virtual_keyboard(void)
+{
+ int err;
+
+ virt_keyboard = input_allocate_device();
+
+ if (!virt_keyboard)
+ return -ENOMEM;
+
+ virt_keyboard->name = "Speakup";
+ virt_keyboard->id.bustype = BUS_VIRTUAL;
+ virt_keyboard->phys = "speakup/input0";
+ virt_keyboard->dev.parent = NULL;
+
+ __set_bit(EV_KEY, virt_keyboard->evbit);
+ __set_bit(KEY_DOWN, virt_keyboard->keybit);
+
+ err = input_register_device(virt_keyboard);
+ if (err) {
+ input_free_device(virt_keyboard);
+ virt_keyboard = NULL;
+ }
+
+ return err;
+}
+
+void speakup_remove_virtual_keyboard(void)
+{
+ if (virt_keyboard) {
+ input_unregister_device(virt_keyboard);
+ virt_keyboard = NULL;
+ }
+}
+
+/*
+ * Send a simulated down-arrow to the application.
+ */
+void speakup_fake_down_arrow(void)
+{
+ unsigned long flags;
+
+ /* disable keyboard interrupts */
+ local_irq_save(flags);
+ /* don't change CPU */
+ preempt_disable();
+
+ __this_cpu_write(reporting_keystroke, true);
+ input_report_key(virt_keyboard, KEY_DOWN, PRESSED);
+ input_report_key(virt_keyboard, KEY_DOWN, RELEASED);
+ input_sync(virt_keyboard);
+ __this_cpu_write(reporting_keystroke, false);
+
+ /* reenable preemption */
+ preempt_enable();
+ /* reenable keyboard interrupts */
+ local_irq_restore(flags);
+}
+
+/*
+ * Are we handling a simulated keypress on the current CPU?
+ * Returns a boolean.
+ */
+bool speakup_fake_key_pressed(void)
+{
+ return this_cpu_read(reporting_keystroke);
+}