Make "detected_host_os()" available on the SLAVE side of the split keyboard (#19854)

Co-authored-by: ngs.ch <ngs.ch>
Co-authored-by: Drashna Jaelre <drashna@drashna.net>

5 files changed, 73 insertions, 19 deletions

diff --git a/quantum/os_detection.c b/quantum/os_detection.c
index b1511afb14..e606227136 100644
--- a/quantum/os_detection.c
+++ b/quantum/os_detection.c
@@ -31,53 +31,53 @@ uint16_t usb_setups[STORED_USB_SETUPS];
 
 #ifdef OS_DETECTION_ENABLE
 struct setups_data_t {
-    uint8_t      count;
-    uint8_t      cnt_02;
-    uint8_t      cnt_04;
-    uint8_t      cnt_ff;
-    uint16_t     last_wlength;
-    os_variant_t detected_os;
+    uint8_t  count;
+    uint8_t  cnt_02;
+    uint8_t  cnt_04;
+    uint8_t  cnt_ff;
+    uint16_t last_wlength;
 };
 
 struct setups_data_t setups_data = {
-    .count       = 0,
-    .cnt_02      = 0,
-    .cnt_04      = 0,
-    .cnt_ff      = 0,
-    .detected_os = OS_UNSURE,
+    .count  = 0,
+    .cnt_02 = 0,
+    .cnt_04 = 0,
+    .cnt_ff = 0,
 };
 
+os_variant_t detected_os = OS_UNSURE;
+
 // Some collected sequences of wLength can be found in tests.
 void make_guess(void) {
     if (setups_data.count < 3) {
         return;
     }
     if (setups_data.cnt_ff >= 2 && setups_data.cnt_04 >= 1) {
-        setups_data.detected_os = OS_WINDOWS;
+        detected_os = OS_WINDOWS;
         return;
     }
     if (setups_data.count == setups_data.cnt_ff) {
         // Linux has 3 packets with 0xFF.
-        setups_data.detected_os = OS_LINUX;
+        detected_os = OS_LINUX;
         return;
     }
     if (setups_data.count == 5 && setups_data.last_wlength == 0xFF && setups_data.cnt_ff == 1 && setups_data.cnt_02 == 2) {
-        setups_data.detected_os = OS_MACOS;
+        detected_os = OS_MACOS;
         return;
     }
     if (setups_data.count == 4 && setups_data.cnt_ff == 0 && setups_data.cnt_02 == 2) {
         // iOS and iPadOS don't have the last 0xFF packet.
-        setups_data.detected_os = OS_IOS;
+        detected_os = OS_IOS;
         return;
     }
     if (setups_data.cnt_ff == 0 && setups_data.cnt_02 == 3 && setups_data.cnt_04 == 1) {
         // This is actually PS5.
-        setups_data.detected_os = OS_LINUX;
+        detected_os = OS_LINUX;
         return;
     }
     if (setups_data.cnt_ff >= 1 && setups_data.cnt_02 == 0 && setups_data.cnt_04 == 0) {
         // This is actually Quest 2 or Nintendo Switch.
-        setups_data.detected_os = OS_LINUX;
+        detected_os = OS_LINUX;
         return;
     }
 }
@@ -99,13 +99,20 @@ void process_wlength(const uint16_t w_length) {
 }
 
 os_variant_t detected_host_os(void) {
-    return setups_data.detected_os;
+    return detected_os;
 }
 
 void erase_wlength_data(void) {
     memset(&setups_data, 0, sizeof(setups_data));
+    detected_os = OS_UNSURE;
+}
+
+#    if defined(SPLIT_KEYBOARD) && defined(SPLIT_DETECTED_OS_ENABLE)
+void slave_update_detected_host_os(os_variant_t os) {
+    detected_os = os;
 }
-#endif // OS_DETECTION_ENABLE
+#    endif // defined(SPLIT_KEYBOARD) && defined(SPLIT_DETECTED_OS_ENABLE)
+#endif     // OS_DETECTION_ENABLE
 
 #ifdef OS_DETECTION_DEBUG_ENABLE
 void print_stored_setups(void) {
diff --git a/quantum/os_detection.h b/quantum/os_detection.h
index e643dcd27f..3496ea0ed2 100644
--- a/quantum/os_detection.h
+++ b/quantum/os_detection.h
@@ -30,6 +30,10 @@ typedef enum {
 void         process_wlength(const uint16_t w_length);
 os_variant_t detected_host_os(void);
 void         erase_wlength_data(void);
+
+#    if defined(SPLIT_KEYBOARD) && defined(SPLIT_DETECTED_OS_ENABLE)
+void slave_update_detected_host_os(os_variant_t os);
+#    endif // defined(SPLIT_KEYBOARD) && defined(SPLIT_DETECTED_OS_ENABLE)
 #endif
 
 #ifdef OS_DETECTION_DEBUG_ENABLE
diff --git a/quantum/split_common/transaction_id_define.h b/quantum/split_common/transaction_id_define.h
index 4932530aa3..4d4d2b9570 100644
--- a/quantum/split_common/transaction_id_define.h
+++ b/quantum/split_common/transaction_id_define.h
@@ -113,6 +113,10 @@ enum serial_transaction_id {
     SPLIT_TRANSACTION_IDS_USER,
 #endif // SPLIT_TRANSACTION_IDS_USER
 
+#if defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+    PUT_DETECTED_OS,
+#endif // defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+
     NUM_TOTAL_TRANSACTIONS
 };
 
diff --git a/quantum/split_common/transactions.c b/quantum/split_common/transactions.c
index 0ae91ba363..b3c80f1194 100644
--- a/quantum/split_common/transactions.c
+++ b/quantum/split_common/transactions.c
@@ -820,6 +820,34 @@ static void activity_handlers_slave(matrix_row_t master_matrix[], matrix_row_t s
 #endif // defined(SPLIT_ACTIVITY_ENABLE)
 
 ////////////////////////////////////////////////////
+// Detected OS
+
+#if defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+
+static bool detected_os_handlers_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+    static uint32_t last_detected_os_update = 0;
+    os_variant_t    detected_os             = detected_host_os();
+    bool            okay                    = send_if_condition(PUT_DETECTED_OS, &last_detected_os_update, (detected_os != split_shmem->detected_os), &detected_os, sizeof(os_variant_t));
+    return okay;
+}
+
+static void detected_os_handlers_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+    slave_update_detected_host_os(split_shmem->detected_os);
+}
+
+#    define TRANSACTIONS_DETECTED_OS_MASTER() TRANSACTION_HANDLER_MASTER(detected_os)
+#    define TRANSACTIONS_DETECTED_OS_SLAVE() TRANSACTION_HANDLER_SLAVE_AUTOLOCK(detected_os)
+#    define TRANSACTIONS_DETECTED_OS_REGISTRATIONS [PUT_DETECTED_OS] = trans_initiator2target_initializer(detected_os),
+
+#else // defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+
+#    define TRANSACTIONS_DETECTED_OS_MASTER()
+#    define TRANSACTIONS_DETECTED_OS_SLAVE()
+#    define TRANSACTIONS_DETECTED_OS_REGISTRATIONS
+
+#endif // defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+
+////////////////////////////////////////////////////
 
 split_transaction_desc_t split_transaction_table[NUM_TOTAL_TRANSACTIONS] = {
     // Set defaults
@@ -848,6 +876,7 @@ split_transaction_desc_t split_transaction_table[NUM_TOTAL_TRANSACTIONS] = {
     TRANSACTIONS_WATCHDOG_REGISTRATIONS
     TRANSACTIONS_HAPTIC_REGISTRATIONS
     TRANSACTIONS_ACTIVITY_REGISTRATIONS
+    TRANSACTIONS_DETECTED_OS_REGISTRATIONS
 // clang-format on
 
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
@@ -877,6 +906,7 @@ bool transactions_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix
     TRANSACTIONS_WATCHDOG_MASTER();
     TRANSACTIONS_HAPTIC_MASTER();
     TRANSACTIONS_ACTIVITY_MASTER();
+    TRANSACTIONS_DETECTED_OS_MASTER();
     return true;
 }
 
@@ -899,6 +929,7 @@ void transactions_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[
     TRANSACTIONS_WATCHDOG_SLAVE();
     TRANSACTIONS_HAPTIC_SLAVE();
     TRANSACTIONS_ACTIVITY_SLAVE();
+    TRANSACTIONS_DETECTED_OS_SLAVE();
 }
 
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
diff --git a/quantum/split_common/transport.h b/quantum/split_common/transport.h
index 13b1e56814..6f8985cb07 100644
--- a/quantum/split_common/transport.h
+++ b/quantum/split_common/transport.h
@@ -142,6 +142,10 @@ typedef struct _rpc_sync_info_t {
 } rpc_sync_info_t;
 #endif // defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
 
+#if defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+#    include "os_detection.h"
+#endif // defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+
 typedef struct _split_shared_memory_t {
 #ifdef USE_I2C
     int8_t transaction_id;
@@ -222,6 +226,10 @@ typedef struct _split_shared_memory_t {
     uint8_t         rpc_m2s_buffer[RPC_M2S_BUFFER_SIZE];
     uint8_t         rpc_s2m_buffer[RPC_S2M_BUFFER_SIZE];
 #endif // defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
+
+#if defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
+    os_variant_t detected_os;
+#endif // defined(OS_DETECTION_ENABLE) && defined(SPLIT_DETECTED_OS_ENABLE)
 } split_shared_memory_t;
 
 extern split_shared_memory_t *const split_shmem;