feat(core): add mock touch driver

diff --git a/core/embed/io/Cargo.toml b/core/embed/io/Cargo.toml
index 3eb53f04..da425ed3 100644
--- a/core/embed/io/Cargo.toml
+++ b/core/embed/io/Cargo.toml
@@ -92,7 +92,7 @@ backlight_tps61043 = []
 backlight_tps61062 = []
 backlight_pin = []
 
-# touch drivers
+touch_none = []
 touch_ft6x36 = []
 touch_ft3168 = []
 touch_stmpe811 = []
diff --git a/core/embed/io/touch/build.rs b/core/embed/io/touch/build.rs
index 8478ba03..b6808735 100644
--- a/core/embed/io/touch/build.rs
+++ b/core/embed/io/touch/build.rs
@@ -23,6 +23,9 @@ pub fn def_module(lib: &mut CLibrary) -> Result<()> {
         // builds the unix driver instead of the HW one. The unix driver does no
         // panel correction, so the selected panel feature is ignored here.
         lib.add_source("touch/unix/touch.c");
+    } else if cfg!(feature = "touch_none") {
+        // Headless boards: touch API present but never reports activity.
+        lib.add_source("touch/none/touch.c");
     } else if cfg!(feature = "touch_ft3168") {
         add_driver_ft3168(lib)?;
     } else if cfg!(feature = "touch_ft6x36") {
diff --git a/core/embed/io/touch/none/touch.c b/core/embed/io/touch/none/touch.c
new file mode 100644
index 00000000..28ed42b7
--- /dev/null
+++ b/core/embed/io/touch/none/touch.c
@@ -0,0 +1,70 @@
+/*
+ * This file is part of the Trezor project, https://trezor.io/
+ *
+ * Copyright (c) SatoshiLabs
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+// Headless ("none") touch driver.
+//
+// Used by boards that have no touch panel (e.g. bare development boards). It
+// satisfies the touch API but never reports any touch activity. This lets the
+// touch-based UI (and the `touch_get_event()` helper in `touch_poll.c`) link
+// and run without touch hardware; the interface simply stays idle.
+
+#include <trezor_rtl.h>
+
+#include <io/touch.h>
+
+#include "../touch_poll.h"
+
+#ifdef KERNEL_MODE
+
+secbool touch_init(void) {
+  // Initialize the polling layer so touch_get_event() works (and always
+  // returns "no event").
+  if (!touch_poll_init()) {
+    return secfalse;
+  }
+  return sectrue;
+}
+
+void touch_deinit(void) { touch_poll_deinit(); }
+
+void touch_power_set(bool on) {}
+
+#ifdef USE_SUSPEND
+void touch_suspend(void) {}
+
+void touch_resume(void) {}
+#endif
+
+secbool touch_ready(void) { return sectrue; }
+
+uint8_t touch_get_version(void) { return 0; }
+
+secbool touch_set_sensitivity(uint8_t value) { return sectrue; }
+
+secbool touch_activity(void) { return secfalse; }
+
+uint32_t touch_get_state(void) { return 0; }
+
+#if defined(USE_SUSPEND) && defined(USE_TOUCH_WAKEUP)
+void touch_wakeup_set_enabled(bool enabled) {}
+
+bool touch_wakeup_get_enabled(void) { return false; }
+#endif
+
+#endif  // KERNEL_MODE