347 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			347 lines
		
	
	
		
			8.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
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"
 | 
						|
#    include "gpio.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 void    pbuf_clear(void);
 | 
						|
bool                  pbuf_has_data(void);
 | 
						|
 | 
						|
#if defined(PROTOCOL_CHIBIOS)
 | 
						|
void ps2_interrupt_service_routine(void);
 | 
						|
void palCallback(void *arg) {
 | 
						|
    ps2_interrupt_service_routine();
 | 
						|
}
 | 
						|
 | 
						|
#    define PS2_INT_INIT()                                 \
 | 
						|
        do {                                               \
 | 
						|
            palSetLineMode(PS2_CLOCK_PIN, PAL_MODE_INPUT); \
 | 
						|
        } while (0)
 | 
						|
#    define PS2_INT_ON()                                                    \
 | 
						|
        do {                                                                \
 | 
						|
            palEnableLineEvent(PS2_CLOCK_PIN, PAL_EVENT_MODE_FALLING_EDGE); \
 | 
						|
            palSetLineCallback(PS2_CLOCK_PIN, palCallback, NULL);           \
 | 
						|
        } while (0)
 | 
						|
#    define PS2_INT_OFF()                       \
 | 
						|
        do {                                    \
 | 
						|
            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;
 | 
						|
}
 | 
						|
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
 | 
						|
}
 |