[Core] Split support for pointing devices. (#15304)

* Draft implementation

* formatting

* fix combined buttons

* remove pimoroni throttle

* sync pointing on a throttle loop with checksum

* no longer used

* doh

Co-authored-by: Drashna Jaelre <drashna@live.com>

* switch pimoroni to a cpi equivalent

* add cpi support

* allow user modification of seperate mouse reports

* a little tidy up

* add *_RIGHT defines.

* docs

* doxygen comments

* basic changelog

* clean up pimoroni

* small doc fixes

* Update docs/feature_pointing_device.md

Co-authored-by: Drashna Jaelre <drashna@live.com>

* performance tweak if side has usb

* Don't run init funtions on wrong side

* renamed some variables for consistency

* fix pimoroni typos

* Clamp instead of OR

* Promote combined values to uint16_t

* Update pointing_device.c

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>

3 files changed, 98 insertions, 0 deletions

diff --git a/quantum/split_common/transaction_id_define.h b/quantum/split_common/transaction_id_define.h
index 535bc21aea..aa71c3621e 100644
--- a/quantum/split_common/transaction_id_define.h
+++ b/quantum/split_common/transaction_id_define.h
@@ -78,6 +78,12 @@ enum serial_transaction_id {
     PUT_ST7565,
 #endif  // defined(ST7565_ENABLE) && defined(SPLIT_ST7565_ENABLE)
 
+#if defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+    GET_POINTING_CHECKSUM,
+    GET_POINTING_DATA,
+    PUT_POINTING_CPI,
+#endif  // defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
     PUT_RPC_INFO,
     PUT_RPC_REQ_DATA,
diff --git a/quantum/split_common/transactions.c b/quantum/split_common/transactions.c
index 3ff87710e7..9622acb377 100644
--- a/quantum/split_common/transactions.c
+++ b/quantum/split_common/transactions.c
@@ -579,6 +579,82 @@ static void st7565_handlers_slave(matrix_row_t master_matrix[], matrix_row_t sla
 #endif  // defined(ST7565_ENABLE) && defined(SPLIT_ST7565_ENABLE)
 
 ////////////////////////////////////////////////////
+// POINTING
+
+#if defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
+static bool pointing_handlers_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+#    if defined(POINTING_DEVICE_LEFT)
+    if (is_keyboard_left()) {
+        return true;
+    }
+#    elif defined(POINTING_DEVICE_RIGHT)
+    if (!is_keyboard_left()) {
+        return true;
+    }
+#    endif
+    static uint32_t last_update = 0;
+    static uint16_t last_cpi    = 0;
+    report_mouse_t  temp_state;
+    uint16_t        temp_cpi;
+    bool            okay = read_if_checksum_mismatch(GET_POINTING_CHECKSUM, GET_POINTING_DATA, &last_update, &temp_state, &split_shmem->pointing.report, sizeof(temp_state));
+    if (okay) pointing_device_set_shared_report(temp_state);
+    temp_cpi = pointing_device_get_shared_cpi();
+    if (temp_cpi && memcmp(&last_cpi, &temp_cpi, sizeof(temp_cpi)) != 0) {
+        memcpy(&split_shmem->pointing.cpi, &temp_cpi, sizeof(temp_cpi));
+        okay = transport_write(PUT_POINTING_CPI, &split_shmem->pointing.cpi, sizeof(split_shmem->pointing.cpi));
+        if (okay) {
+            last_cpi = temp_cpi;
+        }
+    }
+    return okay;
+}
+
+extern const pointing_device_driver_t pointing_device_driver;
+
+static void pointing_handlers_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[]) {
+#    if defined(POINTING_DEVICE_LEFT)
+    if (!is_keyboard_left()) {
+        return;
+    }
+#    elif defined(POINTING_DEVICE_RIGHT)
+    if (is_keyboard_left()) {
+        return;
+    }
+#    endif
+    report_mouse_t temp_report;
+    uint16_t       temp_cpi;
+#    ifdef POINTING_DEVICE_TASK_THROTTLE_MS
+    static uint32_t last_exec = 0;
+    if (timer_elapsed32(last_exec) < POINTING_DEVICE_TASK_THROTTLE_MS) {
+        return;
+    }
+    last_exec = timer_read32();
+#    endif
+    temp_cpi = pointing_device_driver.get_cpi();
+    if (split_shmem->pointing.cpi && memcmp(&split_shmem->pointing.cpi, &temp_cpi, sizeof(temp_cpi)) != 0) {
+        pointing_device_driver.set_cpi(split_shmem->pointing.cpi);
+    }
+    memset(&temp_report, 0, sizeof(temp_report));
+    temp_report = pointing_device_driver.get_report(temp_report);
+    memcpy(&split_shmem->pointing.report, &temp_report, sizeof(temp_report));
+    // Now update the checksum given that the pointing has been written to
+    split_shmem->pointing.checksum = crc8(&temp_report, sizeof(temp_report));
+}
+
+#    define TRANSACTIONS_POINTING_MASTER() TRANSACTION_HANDLER_MASTER(pointing)
+#    define TRANSACTIONS_POINTING_SLAVE() TRANSACTION_HANDLER_SLAVE(pointing)
+#    define TRANSACTIONS_POINTING_REGISTRATIONS [GET_POINTING_CHECKSUM] = trans_target2initiator_initializer(pointing.checksum), [GET_POINTING_DATA] = trans_target2initiator_initializer(pointing.report), [PUT_POINTING_CPI] = trans_initiator2target_initializer(pointing.cpi),
+
+#else  // defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
+#    define TRANSACTIONS_POINTING_MASTER()
+#    define TRANSACTIONS_POINTING_SLAVE()
+#    define TRANSACTIONS_POINTING_REGISTRATIONS
+
+#endif  // defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
+////////////////////////////////////////////////////
 
 uint8_t                  dummy;
 split_transaction_desc_t split_transaction_table[NUM_TOTAL_TRANSACTIONS] = {
@@ -604,6 +680,7 @@ split_transaction_desc_t split_transaction_table[NUM_TOTAL_TRANSACTIONS] = {
     TRANSACTIONS_WPM_REGISTRATIONS
     TRANSACTIONS_OLED_REGISTRATIONS
     TRANSACTIONS_ST7565_REGISTRATIONS
+    TRANSACTIONS_POINTING_REGISTRATIONS
 // clang-format on
 
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
@@ -629,6 +706,7 @@ bool transactions_master(matrix_row_t master_matrix[], matrix_row_t slave_matrix
     TRANSACTIONS_WPM_MASTER();
     TRANSACTIONS_OLED_MASTER();
     TRANSACTIONS_ST7565_MASTER();
+    TRANSACTIONS_POINTING_MASTER();
     return true;
 }
 
@@ -647,6 +725,7 @@ void transactions_slave(matrix_row_t master_matrix[], matrix_row_t slave_matrix[
     TRANSACTIONS_WPM_SLAVE();
     TRANSACTIONS_OLED_SLAVE();
     TRANSACTIONS_ST7565_SLAVE();
+    TRANSACTIONS_POINTING_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 1d4f6ed0cd..31b804908b 100644
--- a/quantum/split_common/transport.h
+++ b/quantum/split_common/transport.h
@@ -106,6 +106,15 @@ typedef struct _split_mods_sync_t {
 } split_mods_sync_t;
 #endif  // SPLIT_MODS_ENABLE
 
+#if defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+#    include "pointing_device.h"
+typedef struct _split_slave_pointing_sync_t {
+    uint8_t        checksum;
+    report_mouse_t report;
+    uint16_t       cpi;
+} split_slave_pointing_sync_t;
+#endif  // defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
 typedef struct _rpc_sync_info_t {
     int8_t  transaction_id;
@@ -173,6 +182,10 @@ typedef struct _split_shared_memory_t {
     uint8_t current_st7565_state;
 #endif  // ST7565_ENABLE(OLED_ENABLE) && defined(SPLIT_ST7565_ENABLE)
 
+#if defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+    split_slave_pointing_sync_t pointing;
+#endif  // defined(POINTING_DEVICE_ENABLE) && defined(SPLIT_POINTING_ENABLE)
+
 #if defined(SPLIT_TRANSACTION_IDS_KB) || defined(SPLIT_TRANSACTION_IDS_USER)
     rpc_sync_info_t rpc_info;
     uint8_t         rpc_m2s_buffer[RPC_M2S_BUFFER_SIZE];