Merge remote-tracking branch 'upstream/develop'

3 files changed, 28 insertions, 11 deletions

diff --git a/quantum/split_common/split_util.c b/quantum/split_common/split_util.c
index 7d50adf758..4892b7f8d8 100644
--- a/quantum/split_common/split_util.c
+++ b/quantum/split_common/split_util.c
@@ -57,8 +57,9 @@ static uint8_t connection_errors = 0;
 volatile bool isLeftHand = true;
 
 #if defined(SPLIT_USB_DETECT)
+_Static_assert((SPLIT_USB_TIMEOUT / SPLIT_USB_TIMEOUT_POLL) <= UINT16_MAX, "Please lower SPLIT_USB_TIMEOUT and/or increase SPLIT_USB_TIMEOUT_POLL.");
 static bool usbIsActive(void) {
-    for (uint8_t i = 0; i < (SPLIT_USB_TIMEOUT / SPLIT_USB_TIMEOUT_POLL); i++) {
+    for (uint16_t i = 0; i < (SPLIT_USB_TIMEOUT / SPLIT_USB_TIMEOUT_POLL); i++) {
         // This will return true if a USB connection has been established
         if (usb_connected_state()) {
             return true;
@@ -93,7 +94,6 @@ static uint8_t peek_matrix_intersection(pin_t out_pin, pin_t in_pin) {
 __attribute__((weak)) bool is_keyboard_left(void) {
 #if defined(SPLIT_HAND_PIN)
     // Test pin SPLIT_HAND_PIN for High/Low, if low it's right hand
-    setPinInput(SPLIT_HAND_PIN);
 #    ifdef SPLIT_HAND_PIN_LOW_IS_LEFT
     return !readPin(SPLIT_HAND_PIN);
 #    else
@@ -132,6 +132,14 @@ __attribute__((weak)) bool is_keyboard_master(void) {
 
 // this code runs before the keyboard is fully initialized
 void split_pre_init(void) {
+#if defined(SPLIT_HAND_PIN)
+    setPinInput(SPLIT_HAND_PIN);
+    wait_us(100);
+#elif defined(EE_HANDS)
+    if (!eeconfig_is_enabled()) {
+        eeconfig_init();
+    }
+#endif
     isLeftHand = is_keyboard_left();
 
 #if defined(RGBLIGHT_ENABLE) && defined(RGBLED_SPLIT)
diff --git a/quantum/split_common/transactions.c b/quantum/split_common/transactions.c
index 9e3df534e3..719068908f 100644
--- a/quantum/split_common/transactions.c
+++ b/quantum/split_common/transactions.c
@@ -694,7 +694,7 @@ split_transaction_desc_t split_transaction_table[NUM_TOTAL_TRANSACTIONS] = {
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
         [PUT_RPC_INFO]  = trans_initiator2target_initializer_cb(rpc_info, slave_rpc_info_callback),
     [PUT_RPC_REQ_DATA]  = trans_initiator2target_initializer(rpc_m2s_buffer),
-    [EXECUTE_RPC]       = trans_initiator2target_initializer_cb(rpc_info.transaction_id, slave_rpc_exec_callback),
+    [EXECUTE_RPC]       = trans_initiator2target_initializer_cb(rpc_info.payload.transaction_id, slave_rpc_exec_callback),
     [GET_RPC_RESP_DATA] = trans_target2initiator_initializer(rpc_s2m_buffer),
 #endif // defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
 };
@@ -760,7 +760,8 @@ bool transaction_rpc_exec(int8_t transaction_id, uint8_t initiator2target_buffer
     if (target2initiator_buffer_size > RPC_S2M_BUFFER_SIZE) return false;
 
     // Prepare the metadata block
-    rpc_sync_info_t info = {.transaction_id = transaction_id, .m2s_length = initiator2target_buffer_size, .s2m_length = target2initiator_buffer_size};
+    rpc_sync_info_t info = {.payload = {.transaction_id = transaction_id, .m2s_length = initiator2target_buffer_size, .s2m_length = target2initiator_buffer_size}};
+    info.checksum        = crc8(&info.payload, sizeof(info.payload));
 
     // Make sure the local side knows that we're not sending the full block of data
     split_transaction_table[PUT_RPC_REQ_DATA].initiator2target_buffer_size  = initiator2target_buffer_size;
@@ -791,18 +792,23 @@ void slave_rpc_info_callback(uint8_t initiator2target_buffer_size, const void *i
     // Ignore the args -- the `split_shmem` already has the info, we just need to act upon it.
     // We must keep the `split_transaction_table` non-const, so that it is able to be modified at runtime.
 
-    split_transaction_table[PUT_RPC_REQ_DATA].initiator2target_buffer_size  = split_shmem->rpc_info.m2s_length;
-    split_transaction_table[GET_RPC_RESP_DATA].target2initiator_buffer_size = split_shmem->rpc_info.s2m_length;
+    split_transaction_table[PUT_RPC_REQ_DATA].initiator2target_buffer_size  = split_shmem->rpc_info.payload.m2s_length;
+    split_transaction_table[GET_RPC_RESP_DATA].target2initiator_buffer_size = split_shmem->rpc_info.payload.s2m_length;
 }
 
 void slave_rpc_exec_callback(uint8_t initiator2target_buffer_size, const void *initiator2target_buffer, uint8_t target2initiator_buffer_size, void *target2initiator_buffer) {
     // We can assume that the buffer lengths are correctly set, now, given that sequentially the rpc_info callback was already executed.
     // Go through the rpc_info and execute _that_ transaction's callback, with the scratch buffers as inputs.
-    int8_t transaction_id = split_shmem->rpc_info.transaction_id;
+    // As a safety precaution we check that the received payload matches its checksum first.
+    if (crc8(&split_shmem->rpc_info.payload, sizeof(split_shmem->rpc_info.payload)) != split_shmem->rpc_info.checksum) {
+        return;
+    }
+
+    int8_t transaction_id = split_shmem->rpc_info.payload.transaction_id;
     if (transaction_id < NUM_TOTAL_TRANSACTIONS) {
         split_transaction_desc_t *trans = &split_transaction_table[transaction_id];
         if (trans->slave_callback) {
-            trans->slave_callback(split_shmem->rpc_info.m2s_length, split_shmem->rpc_m2s_buffer, split_shmem->rpc_info.s2m_length, split_shmem->rpc_s2m_buffer);
+            trans->slave_callback(split_shmem->rpc_info.payload.m2s_length, split_shmem->rpc_m2s_buffer, split_shmem->rpc_info.payload.s2m_length, split_shmem->rpc_s2m_buffer);
         }
     }
 }
diff --git a/quantum/split_common/transport.h b/quantum/split_common/transport.h
index e62679990a..06778ad14a 100644
--- a/quantum/split_common/transport.h
+++ b/quantum/split_common/transport.h
@@ -116,9 +116,12 @@ typedef struct _split_slave_pointing_sync_t {
 
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
 typedef struct _rpc_sync_info_t {
-    int8_t  transaction_id;
-    uint8_t m2s_length;
-    uint8_t s2m_length;
+    uint8_t checksum;
+    struct {
+        int8_t  transaction_id;
+        uint8_t m2s_length;
+        uint8_t s2m_length;
+    } payload;
 } rpc_sync_info_t;
 #endif // defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)