refactor(core): make wireless charging driver optional

diff --git a/core/embed/io/Cargo.toml b/core/embed/io/Cargo.toml
index 58240570..f61ef39a 100644
--- a/core/embed/io/Cargo.toml
+++ b/core/embed/io/Cargo.toml
@@ -54,6 +54,7 @@ hw_jpeg_decoder = []
 lockable_bootloader = ["sec/lockable_bootloader"]
 pmic = ["sys/i2c_bus"]
 power_manager = ["pmic", "sys/i2c_bus"]
+wireless_stwlc38 = ["sys/i2c_bus"]
 production = ["sec/production"]
 raspi_emulator = []
 rgb_led = []
diff --git a/core/embed/io/power_manager/build.rs b/core/embed/io/power_manager/build.rs
index 174bf7b0..7391509c 100644
--- a/core/embed/io/power_manager/build.rs
+++ b/core/embed/io/power_manager/build.rs
@@ -23,6 +23,19 @@ pub fn def_module(lib: &mut CLibrary) -> Result<()> {
 
     lib.add_source("power_manager/power_manager_poll.c");
 
+    // --- Optional wireless charger ----------------------------------------
+    // Not present in the emulator (the STWLC38 driver needs the STM32 HAL).
+    if cfg!(feature = "wireless_stwlc38") && cfg!(not(feature = "emulator")) {
+        lib.add_define("USE_WIRELESS_CHARGER", Some("1"));
+        if cfg!(feature = "mcu_stm32u5") {
+            lib.add_sources([
+                "power_manager/stwlc38/stwlc38.c",
+                "power_manager/stwlc38/stwlc38_patching.c",
+            ]);
+        }
+    }
+
+    // --- Power manager backend --------------------------------------------
     if cfg!(feature = "emulator") {
         lib.add_source("power_manager/unix/power_manager.c");
     } else if cfg!(feature = "mcu_stm32u5") {
@@ -33,8 +46,6 @@ pub fn def_module(lib: &mut CLibrary) -> Result<()> {
             "power_manager/battery/battery.c",
             "power_manager/battery/fuel_gauge.c",
             "power_manager/battery/battery_model.c",
-            "power_manager/stwlc38/stwlc38.c",
-            "power_manager/stwlc38/stwlc38_patching.c",
         ]);
     } else {
         bail_unsupported!();
diff --git a/core/embed/io/power_manager/stm32u5/power_manager.c b/core/embed/io/power_manager/stm32u5/power_manager.c
index 782dc769..9aadad13 100644
--- a/core/embed/io/power_manager/stm32u5/power_manager.c
+++ b/core/embed/io/power_manager/stm32u5/power_manager.c
@@ -63,11 +63,18 @@ pm_status_t pm_init(bool inherit_state) {
   memset(drv, 0, sizeof(pm_driver_t));
 
   // Initialize hardware subsystems
-  if (!pmic_init() || !stwlc38_init()) {
+  if (!pmic_init()) {
     pm_deinit();
     return PM_ERROR;
   }
 
+#ifdef USE_WIRELESS_CHARGER
+  if (!stwlc38_init()) {
+    pm_deinit();
+    return PM_ERROR;
+  }
+#endif
+
   if (!pm_poll_init()) {
     pm_deinit();
     return PM_ERROR;
@@ -202,7 +209,9 @@ void pm_deinit(void) {
   }
 
   pmic_deinit();
+#ifdef USE_WIRELESS_CHARGER
   stwlc38_deinit();
+#endif
 
   drv->initialized = false;
 }
@@ -630,6 +639,12 @@ bool pm_driver_suspend(void) {
 
   irq_unlock(irq_key);
 
+  // Suspend the sub-drivers owned by the power manager.
+  pmic_suspend();
+#ifdef USE_WIRELESS_CHARGER
+  stwlc38_suspend();
+#endif
+
   return true;
 }
 
@@ -701,6 +716,12 @@ bool pm_usb_is_connected(void) {
 }
 
 bool pm_driver_resume(void) {
+  // Resume the sub-drivers owned by the power manager.
+#ifdef USE_WIRELESS_CHARGER
+  stwlc38_resume();
+#endif
+  pmic_resume();
+
   pm_driver_t* drv = &g_pm;
 
   if (!drv->initialized) {
@@ -748,6 +769,12 @@ bool pm_driver_is_suspended(void) {
   suspended = drv->suspended;
   irq_unlock(irq_key);
 
+  // The power manager is only fully suspended once its sub-drivers are too.
+  suspended = suspended && pmic_is_suspended();
+#ifdef USE_WIRELESS_CHARGER
+  suspended = suspended && stwlc38_is_suspended();
+#endif
+
   return suspended;
 }
 
diff --git a/core/embed/io/power_manager/stm32u5/power_monitoring.c b/core/embed/io/power_manager/stm32u5/power_monitoring.c
index e945c919..832092b0 100644
--- a/core/embed/io/power_manager/stm32u5/power_monitoring.c
+++ b/core/embed/io/power_manager/stm32u5/power_monitoring.c
@@ -77,7 +77,9 @@ void pm_pmic_data_ready(void* context, pmic_report_t* report) {
   memcpy(&drv->pmic_data, report, sizeof(pmic_report_t));
 
   // Get wireless charger data
+#ifdef USE_WIRELESS_CHARGER
   stwlc38_get_report(&drv->wireless_data);
+#endif
 
 #ifdef USE_TELEMETRY
   // Update telemetry with the current battery temperature
diff --git a/core/embed/io/suspend/stm32u5/suspend.c b/core/embed/io/suspend/stm32u5/suspend.c
index ca4ed821..cea8f142 100644
--- a/core/embed/io/suspend/stm32u5/suspend.c
+++ b/core/embed/io/suspend/stm32u5/suspend.c
@@ -26,8 +26,6 @@
 #include <sec/suspend_io.h>
 #include <sys/irq.h>
 
-#include <../../power_manager/stwlc38/stwlc38.h>
-#include <io/pmic.h>
 #include <io/power_manager.h>
 
 #ifdef USE_RGB_LED
@@ -147,21 +145,15 @@ wakeup_flags_t system_suspend(void) {
   return wakeup_flags;
 }
 
-static void background_tasks_suspend(void) {
-  pm_driver_suspend();
-  pmic_suspend();
-  stwlc38_suspend();
-}
+// The power manager owns its sub-drivers (PMIC, wireless charger); it
+// suspends/resumes them internally, so the suspend framework only deals with
+// the pm_driver_* interface and stays unaware of which power hardware exists.
+static void background_tasks_suspend(void) { pm_driver_suspend(); }
 
 static bool background_tasks_suspended(void) {
-  return pmic_is_suspended() && stwlc38_is_suspended() &&
-         pm_driver_is_suspended();
+  return pm_driver_is_suspended();
 }
 
-static void background_tasks_resume(void) {
-  stwlc38_resume();
-  pmic_resume();
-  pm_driver_resume();
-}
+static void background_tasks_resume(void) { pm_driver_resume(); }
 
 #endif  // defined(KERNEL_MODE) && !defined(SECMON)
diff --git a/core/embed/models/T3W1/boards/revA.toml b/core/embed/models/T3W1/boards/revA.toml
index dc74a5b4..1f0f185c 100644
--- a/core/embed/models/T3W1/boards/revA.toml
+++ b/core/embed/models/T3W1/boards/revA.toml
@@ -25,6 +25,7 @@ panel = "io/touch_panel_lx250a2410a"
 [rgb_led]
 
 [power_manager]
+wireless = "io/wireless_stwlc38"
 
 [nfc]
 
diff --git a/core/embed/models/T3W1/boards/revB.toml b/core/embed/models/T3W1/boards/revB.toml
index ceba657f..915da087 100644
--- a/core/embed/models/T3W1/boards/revB.toml
+++ b/core/embed/models/T3W1/boards/revB.toml
@@ -25,6 +25,7 @@ panel = "io/touch_panel_lx250a2410a"
 [rgb_led]
 
 [power_manager]
+wireless = "io/wireless_stwlc38"
 
 [nfc]
 
diff --git a/core/embed/models/T3W1/boards/revC.toml b/core/embed/models/T3W1/boards/revC.toml
index d5a1fa48..b939ec04 100644
--- a/core/embed/models/T3W1/boards/revC.toml
+++ b/core/embed/models/T3W1/boards/revC.toml
@@ -25,6 +25,7 @@ panel = "io/touch_panel_lx250a2410a"
 [rgb_led]
 
 [power_manager]
+wireless = "io/wireless_stwlc38"
 
 [nfc]
 
diff --git a/core/embed/projects/prodtest/cmd/prodtest_wpc.c b/core/embed/projects/prodtest/cmd/prodtest_wpc.c
index 891181f7..84b5a10e 100644
--- a/core/embed/projects/prodtest/cmd/prodtest_wpc.c
+++ b/core/embed/projects/prodtest/cmd/prodtest_wpc.c
@@ -17,7 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifdef USE_POWER_MANAGER
+#ifdef USE_WIRELESS_CHARGER
 
 #include <trezor_rtl.h>
 
@@ -183,4 +183,4 @@ PRODTEST_CLI_CMD(
   .args = ""
 );
 
-#endif // USE_POWER_MANAGER
+#endif // USE_WIRELESS_CHARGER