1 files changed, 340 insertions, 0 deletions

diff --git a/drivers/ps2/ps2_interrupt.c b/drivers/ps2/ps2_interrupt.c
new file mode 100644
index 000000000..70debd02f
--- /dev/null
+++ b/drivers/ps2/ps2_interrupt.c
@@ -0,0 +1,340 @@
+/*
+Copyright 2010,2011,2012,2013 Jun WAKO <wakojun@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.
+*/
+
+/*
+ * PS/2 protocol Pin interrupt version
+ */
+
+#include <stdbool.h>
+
+#if defined(__AVR__)
+#    include <avr/interrupt.h>
+#elif defined(PROTOCOL_CHIBIOS)  // TODO: or STM32 ?
+// chibiOS headers
+#    include "ch.h"
+#    include "hal.h"
+#endif
+
+#include "ps2.h"
+#include "ps2_io.h"
+#include "print.h"
+#include "wait.h"
+
+#define WAIT(stat, us, err)     \
+    do {                        \
+        if (!wait_##stat(us)) { \
+            ps2_error = err;    \
+            goto ERROR;         \
+        }                       \
+    } while (0)
+
+uint8_t ps2_error = PS2_ERR_NONE;
+
+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);
+
+#if defined(PROTOCOL_CHIBIOS)
+void ps2_interrupt_service_routine(void);
+void palCallback(void *arg) { ps2_interrupt_service_routine(); }
+
+#    define PS2_INT_INIT()                                 \
+        { palSetLineMode(PS2_CLOCK_PIN, PAL_MODE_INPUT); } \
+        while (0)
+#    define PS2_INT_ON()                                                    \
+        {                                                                   \
+            palEnableLineEvent(PS2_CLOCK_PIN, PAL_EVENT_MODE_FALLING_EDGE); \
+            palSetLineCallback(PS2_CLOCK_PIN, palCallback, NULL);           \
+        }                                                                   \
+        while (0)
+#    define PS2_INT_OFF()                       \
+        { palDisableLineEvent(PS2_CLOCK_PIN); } \
+        while (0)
+#endif  // PROTOCOL_CHIBIOS
+
+void ps2_host_init(void) {
+    idle();
+    PS2_INT_INIT();
+    PS2_INT_ON();
+    // POR(150-2000ms) plus BAT(300-500ms) may take 2.5sec([3]p.20)
+    // wait_ms(2500);
+}
+
+uint8_t ps2_host_send(uint8_t data) {
+    bool parity = true;
+    ps2_error   = PS2_ERR_NONE;
+
+    PS2_INT_OFF();
+
+    /* terminate a transmission if we have */
+    inhibit();
+    wait_us(100);  // 100us [4]p.13, [5]p.50
+
+    /* 'Request to Send' and Start bit */
+    data_lo();
+    clock_hi();
+    WAIT(clock_lo, 10000, 10);  // 10ms [5]p.50
+
+    /* Data bit[2-9] */
+    for (uint8_t i = 0; i < 8; i++) {
+        if (data & (1 << i)) {
+            parity = !parity;
+            data_hi();
+        } else {
+            data_lo();
+        }
+        WAIT(clock_hi, 50, 2);
+        WAIT(clock_lo, 50, 3);
+    }
+
+    /* Parity bit */
+    wait_us(15);
+    if (parity) {
+        data_hi();
+    } else {
+        data_lo();
+    }
+    WAIT(clock_hi, 50, 4);
+    WAIT(clock_lo, 50, 5);
+
+    /* Stop bit */
+    wait_us(15);
+    data_hi();
+
+    /* Ack */
+    WAIT(data_lo, 50, 6);
+    WAIT(clock_lo, 50, 7);
+
+    /* wait for idle state */
+    WAIT(clock_hi, 50, 8);
+    WAIT(data_hi, 50, 9);
+
+    idle();
+    PS2_INT_ON();
+    return ps2_host_recv_response();
+ERROR:
+    idle();
+    PS2_INT_ON();
+    return 0;
+}
+
+uint8_t ps2_host_recv_response(void) {
+    // Command may take 25ms/20ms at most([5]p.46, [3]p.21)
+    uint8_t retry = 25;
+    while (retry-- && !pbuf_has_data()) {
+        wait_ms(1);
+    }
+    return pbuf_dequeue();
+}
+
+/* get data received by interrupt */
+uint8_t ps2_host_recv(void) {
+    if (pbuf_has_data()) {
+        ps2_error = PS2_ERR_NONE;
+        return pbuf_dequeue();
+    } else {
+        ps2_error = PS2_ERR_NODATA;
+        return 0;
+    }
+}
+
+void ps2_interrupt_service_routine(void) {
+    static enum {
+        INIT,
+        START,
+        BIT0,
+        BIT1,
+        BIT2,
+        BIT3,
+        BIT4,
+        BIT5,
+        BIT6,
+        BIT7,
+        PARITY,
+        STOP,
+    } state               = INIT;
+    static uint8_t data   = 0;
+    static uint8_t parity = 1;
+
+    // TODO: abort if elapse 100us from previous interrupt
+
+    // return unless falling edge
+    if (clock_in()) {
+        goto RETURN;
+    }
+
+    state++;
+    switch (state) {
+        case START:
+            if (data_in()) goto ERROR;
+            break;
+        case BIT0:
+        case BIT1:
+        case BIT2:
+        case BIT3:
+        case BIT4:
+        case BIT5:
+        case BIT6:
+        case BIT7:
+            data >>= 1;
+            if (data_in()) {
+                data |= 0x80;
+                parity++;
+            }
+            break;
+        case PARITY:
+            if (data_in()) {
+                if (!(parity & 0x01)) goto ERROR;
+            } else {
+                if (parity & 0x01) goto ERROR;
+            }
+            break;
+        case STOP:
+            if (!data_in()) goto ERROR;
+            pbuf_enqueue(data);
+            goto DONE;
+            break;
+        default:
+            goto ERROR;
+    }
+    goto RETURN;
+ERROR:
+    ps2_error = state;
+DONE:
+    state  = INIT;
+    data   = 0;
+    parity = 1;
+RETURN:
+    return;
+}
+
+#if defined(__AVR__)
+ISR(PS2_INT_VECT) { ps2_interrupt_service_routine(); }
+#endif
+
+/* send LED state to keyboard */
+void ps2_host_set_led(uint8_t led) {
+    ps2_host_send(0xED);
+    ps2_host_send(led);
+}
+
+/*--------------------------------------------------------------------
+ * 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) {
+#if defined(__AVR__)
+    uint8_t sreg = SREG;
+    cli();
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysLockFromISR();
+#endif
+
+    uint8_t next = (pbuf_head + 1) % PBUF_SIZE;
+    if (next != pbuf_tail) {
+        pbuf[pbuf_head] = data;
+        pbuf_head       = next;
+    } else {
+        print("pbuf: full\n");
+    }
+
+#if defined(__AVR__)
+    SREG = sreg;
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysUnlockFromISR();
+#endif
+}
+static inline uint8_t pbuf_dequeue(void) {
+    uint8_t val = 0;
+
+#if defined(__AVR__)
+    uint8_t sreg = SREG;
+    cli();
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysLock();
+#endif
+
+    if (pbuf_head != pbuf_tail) {
+        val       = pbuf[pbuf_tail];
+        pbuf_tail = (pbuf_tail + 1) % PBUF_SIZE;
+    }
+
+#if defined(__AVR__)
+    SREG = sreg;
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysUnlock();
+#endif
+
+    return val;
+}
+static inline bool pbuf_has_data(void) {
+#if defined(__AVR__)
+    uint8_t sreg = SREG;
+    cli();
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysLock();
+#endif
+
+    bool has_data = (pbuf_head != pbuf_tail);
+
+#if defined(__AVR__)
+    SREG = sreg;
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysUnlock();
+#endif
+    return has_data;
+}
+static inline void pbuf_clear(void) {
+#if defined(__AVR__)
+    uint8_t sreg = SREG;
+    cli();
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysLock();
+#endif
+
+    pbuf_head = pbuf_tail = 0;
+
+#if defined(__AVR__)
+    SREG = sreg;
+#elif defined(PROTOCOL_CHIBIOS)
+    chSysUnlock();
+#endif
+}