Move converter specific tmk_core protocols (#14743)

2021-10-07 23:14:26 +01:00 · 2021-10-07 23:14:26 +01:00 · e0d688d4c8
commit e0d688d4c8
parent c39170b7ef
13 changed files with 15 additions and 34 deletions
--- a/keyboards/converter/xt_usb/xt_interrupt.c
+++ b/keyboards/converter/xt_usb/xt_interrupt.c
@ -0,0 +1,166 @@
+/*
+Copyright 2018 Jun WAKO <wakojun@gmail.com>
+Copyright 2016 Ethan Apodaca <papodaca@gmail.com>
+
+This software is licensed with a Modified BSD License.
+All of this is supposed to be Free Software, Open Source, DFSG-free,
+GPL-compatible, and OK to use in both free and proprietary applications.
+Additions and corrections to this file are welcome.
+
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright
+  notice, this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright
+  notice, this list of conditions and the following disclaimer in
+  the documentation and/or other materials provided with the
+  distribution.
+
+* Neither the name of the copyright holders nor the names of
+  contributors may be used to endorse or promote products derived
+  from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <stdbool.h>
+#include <avr/interrupt.h>
+#include "xt.h"
+#include "wait.h"
+#include "debug.h"
+
+static inline uint8_t pbuf_dequeue(void);
+static inline void    pbuf_enqueue(uint8_t data);
+static inline bool    pbuf_has_data(void);
+static inline void    pbuf_clear(void);
+
+void xt_host_init(void) {
+    XT_INT_INIT();
+    XT_INT_OFF();
+
+    /* hard reset */
+#ifdef XT_RESET
+    XT_RESET();
+#endif
+
+    /* soft reset: pull clock line down for 20ms */
+    XT_DATA_LO();
+    XT_CLOCK_LO();
+    wait_ms(20);
+
+    /* input mode with pullup */
+    XT_CLOCK_IN();
+    XT_DATA_IN();
+
+    XT_INT_ON();
+}
+
+/* get data received by interrupt */
+uint8_t xt_host_recv(void) {
+    if (pbuf_has_data()) {
+        return pbuf_dequeue();
+    } else {
+        return 0;
+    }
+}
+
+ISR(XT_INT_VECT) {
+    /*
+     * XT signal format consits of 10 or 9 clocks and sends start bits and 8-bit data,
+     * which should be read on falling edge of clock.
+     *
+     *  start(0), start(1), bit0, bit1, bit2, bit3, bit4, bit5, bit6, bit7
+     *
+     * Original IBM XT keyboard sends start(0) bit while some of clones don't.
+     * Start(0) bit is read as low on data line while start(1) as high.
+     *
+     * https://github.com/tmk/tmk_keyboard/wiki/IBM-PC-XT-Keyboard-Protocol
+     */
+    static enum { START, BIT0, BIT1, BIT2, BIT3, BIT4, BIT5, BIT6, BIT7 } state = START;
+    static uint8_t data                                                         = 0;
+
+    uint8_t dbit = XT_DATA_READ();
+
+    // This is needed if using PCINT which can be called on both falling and rising edge
+    // if (XT_CLOCK_READ()) return;
+
+    switch (state) {
+        case START:
+            // ignore start(0) bit
+            if (!dbit) return;
+            break;
+        case BIT0 ... BIT7:
+            data >>= 1;
+            if (dbit) data |= 0x80;
+            break;
+    }
+    if (state++ == BIT7) {
+        pbuf_enqueue(data);
+        state = START;
+        data  = 0;
+    }
+    return;
+}
+
+/*--------------------------------------------------------------------
+ * Ring buffer to store scan codes from keyboard
+ *------------------------------------------------------------------*/
+#define PBUF_SIZE 32
+static uint8_t pbuf[PBUF_SIZE];
+static uint8_t pbuf_head = 0;
+static uint8_t pbuf_tail = 0;
+
+static inline void pbuf_enqueue(uint8_t data) {
+    uint8_t sreg = SREG;
+    cli();
+    uint8_t next = (pbuf_head + 1) % PBUF_SIZE;
+    if (next != pbuf_tail) {
+        pbuf[pbuf_head] = data;
+        pbuf_head       = next;
+    } else {
+        dprintf("pbuf: full\n");
+    }
+    SREG = sreg;
+}
+
+static inline uint8_t pbuf_dequeue(void) {
+    uint8_t val = 0;
+
+    uint8_t sreg = SREG;
+    cli();
+    if (pbuf_head != pbuf_tail) {
+        val       = pbuf[pbuf_tail];
+        pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE;
+    }
+    SREG = sreg;
+
+    return val;
+}
+
+static inline bool pbuf_has_data(void) {
+    uint8_t sreg = SREG;
+    cli();
+    bool has_data = (pbuf_head != pbuf_tail);
+    SREG          = sreg;
+    return has_data;
+}
+
+static inline void pbuf_clear(void) {
+    uint8_t sreg = SREG;
+    cli();
+    pbuf_head = pbuf_tail = 0;
+    SREG                  = sreg;
+}