Add ps2_busywait.c and recfactor PS/2 protocol
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					 5 changed files with 363 additions and 53 deletions
				
			
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			@ -91,6 +91,9 @@ uint8_t ps2_error = PS2_ERR_NONE;
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void ps2_host_init(void)
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{
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    // POR(150-2000ms) plus BAT(300-500ms) may take 2.5sec([3]p.20)
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    _delay_ms(2500);
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#ifdef PS2_USE_INT
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    PS2_INT_INIT();
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    PS2_INT_ON();
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			@ -163,23 +166,11 @@ ERROR:
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/* receive data when host want else inhibit communication */
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uint8_t ps2_host_recv_response(void)
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{
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    // Command might take 20ms to response([3]p.21)
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    // TrackPoint might take 25ms ([5]2.7)
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    uint8_t data = 0;
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#ifdef PS2_USE_INT
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    PS2_INT_OFF();
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#endif
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    /* terminate a transmission if we have */
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    inhibit();
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    _delay_us(100);
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    /* release lines(idle state) */
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    idle();
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    /* wait start bit */
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    wait_clock_lo(25000);    // command response may take 20 ms at most
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    data = recv_data();
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    inhibit();
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    uint8_t try = 200;
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    while (try-- && (data = ps2_host_recv())) ;
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    return data;
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}
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#endif
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			@ -187,7 +178,17 @@ uint8_t ps2_host_recv_response(void)
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#ifndef PS2_USE_INT
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uint8_t ps2_host_recv(void)
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{
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    return ps2_host_recv_response();
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    uint8_t data = 0;
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    /* release lines(idle state) */
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    idle();
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    /* wait start bit */
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    wait_clock_lo(100); // TODO: this is enough?
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    data = recv_data();
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    inhibit();
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    return data;
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}
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#else
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/* ring buffer to store ps/2 key data */
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			@ -241,13 +242,6 @@ static inline void pbuf_clear(void)
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/* get data received by interrupt */
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uint8_t ps2_host_recv(void)
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{
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    if (ps2_error) {
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        print("x");
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        phex(ps2_error);
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        ps2_host_send(0xFE);    // request to resend
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        ps2_error = PS2_ERR_NONE;
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    }
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    idle();
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    return pbuf_dequeue();
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}
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			@ -450,3 +444,26 @@ static inline void inhibit(void)
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    clock_lo();
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    data_hi();
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}
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/* PS/2 Resources
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 *
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 * [1] The PS/2 Mouse/Keyboard Protocol
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 * http://www.computer-engineering.org/ps2protocol/
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 * Concise and thorough primer of PS/2 protocol.
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 *
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 * [2] Keyboard and Auxiliary Device Controller
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 * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
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 * Signal Timing and Format
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 *
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 * [3] Keyboards(101- and 102-key)
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 * http://www.mcamafia.de/pdf/ibm_hitrc11.pdf
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 * Keyboard Layout, Scan Code Set, POR, and Commands.
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 *
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 * [4] PS/2 Reference Manuals
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 * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
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 * Collection of IBM Personal System/2 documents.
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 *
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 * [5] TrackPoint Engineering Specifications for version 3E
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 * https://web.archive.org/web/20100526161812/http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
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 */
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										142
									
								
								protocol/ps2.h
									
										
									
									
									
								
							
							
						
						
									
										142
									
								
								protocol/ps2.h
									
										
									
									
									
								
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			@ -1,5 +1,5 @@
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/*
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Copyright 2010,2011 Jun WAKO <wakojun@gmail.com>
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Copyright 2010,2011,2012,2013 Jun WAKO <wakojun@gmail.com>
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This software is licensed with a Modified BSD License.
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All of this is supposed to be Free Software, Open Source, DFSG-free,
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			@ -37,12 +37,60 @@ POSSIBILITY OF SUCH DAMAGE.
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#ifndef PS2_H
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#define PS2_H
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#include <stdbool.h>
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#include <util/delay.h>
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#include <avr/io.h>
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/*
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 * Primitive PS/2 Library for AVR
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 *
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 * PS/2 Resources
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 * --------------
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 * [1] The PS/2 Mouse/Keyboard Protocol
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 * http://www.computer-engineering.org/ps2protocol/
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 * Concise and thorough primer of PS/2 protocol.
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 *
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 * [2] Keyboard and Auxiliary Device Controller
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 * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
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 * Signal Timing and Format
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 *
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 * [3] Keyboards(101- and 102-key)
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 * http://www.mcamafia.de/pdf/ibm_hitrc11.pdf
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 * Keyboard Layout, Scan Code Set, POR, and Commands.
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 *
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 * [4] PS/2 Reference Manuals
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 * http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
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 * Collection of IBM Personal System/2 documents.
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 *
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 * [5] TrackPoint Engineering Specifications for version 3E
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 * https://web.archive.org/web/20100526161812/http://wwwcssrv.almaden.ibm.com/trackpoint/download.html
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 */
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#define PS2_ACK         0xFA
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#define PS2_RESEND      0xFE
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#define PS2_SET_LED     0xED
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#define PS2_ERR_NONE        0
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#define PS2_ERR_STARTBIT1   1
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#define PS2_ERR_STARTBIT2   2
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#define PS2_ERR_STARTBIT3   3
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#define PS2_ERR_PARITY      0x10
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#define PS2_LED_SCROLL_LOCK 0
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#define PS2_LED_NUM_LOCK    1
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#define PS2_LED_CAPS_LOCK   2
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/* port settings for clock and data line */
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extern uint8_t ps2_error;
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void ps2_host_init(void);
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uint8_t ps2_host_send(uint8_t data);
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uint8_t ps2_host_recv_response(void);
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uint8_t ps2_host_recv(void);
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void ps2_host_set_led(uint8_t usb_led);
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/* Check port settings for clock and data line */
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#if !(defined(PS2_CLOCK_PORT) && \
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      defined(PS2_CLOCK_PIN) && \
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      defined(PS2_CLOCK_DDR) && \
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			@ -57,27 +105,79 @@ POSSIBILITY OF SUCH DAMAGE.
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#   error "PS/2 data port setting is required in config.h"
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#endif
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#define PS2_ACK         0xFA
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#define PS2_RESEND      0xFE
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#define PS2_SET_LED     0xED
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/*--------------------------------------------------------------------
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 * static functions
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 *------------------------------------------------------------------*/
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static inline void clock_lo(void)
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{
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    PS2_CLOCK_PORT &= ~(1<<PS2_CLOCK_BIT);
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    PS2_CLOCK_DDR  |=  (1<<PS2_CLOCK_BIT);
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}
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static inline void clock_hi(void)
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{
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    /* input with pull up */
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    PS2_CLOCK_DDR  &= ~(1<<PS2_CLOCK_BIT);
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    PS2_CLOCK_PORT |=  (1<<PS2_CLOCK_BIT);
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}
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static inline bool clock_in(void)
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{
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    PS2_CLOCK_DDR  &= ~(1<<PS2_CLOCK_BIT);
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    PS2_CLOCK_PORT |=  (1<<PS2_CLOCK_BIT);
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    _delay_us(1);
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    return PS2_CLOCK_PIN&(1<<PS2_CLOCK_BIT);
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}
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static inline void data_lo(void)
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{
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    PS2_DATA_PORT &= ~(1<<PS2_DATA_BIT);
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    PS2_DATA_DDR  |=  (1<<PS2_DATA_BIT);
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}
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static inline void data_hi(void)
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{
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    /* input with pull up */
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    PS2_DATA_DDR  &= ~(1<<PS2_DATA_BIT);
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    PS2_DATA_PORT |=  (1<<PS2_DATA_BIT);
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}
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static inline bool data_in(void)
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{
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    PS2_DATA_DDR  &= ~(1<<PS2_DATA_BIT);
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    PS2_DATA_PORT |=  (1<<PS2_DATA_BIT);
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    _delay_us(1);
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    return PS2_DATA_PIN&(1<<PS2_DATA_BIT);
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}
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#define PS2_ERR_NONE    0
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#define PS2_ERR_PARITY  0x10
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static inline uint16_t wait_clock_lo(uint16_t us)
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{
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    while (clock_in()  && us) { asm(""); _delay_us(1); us--; }
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    return us;
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}
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static inline uint16_t wait_clock_hi(uint16_t us)
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{
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    while (!clock_in() && us) { asm(""); _delay_us(1); us--; }
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    return us;
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}
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static inline uint16_t wait_data_lo(uint16_t us)
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{
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    while (data_in() && us)  { asm(""); _delay_us(1); us--; }
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    return us;
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}
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static inline uint16_t wait_data_hi(uint16_t us)
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{
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    while (!data_in() && us)  { asm(""); _delay_us(1); us--; }
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    return us;
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}
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#define PS2_LED_SCROLL_LOCK 0
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#define PS2_LED_NUM_LOCK    1
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#define PS2_LED_CAPS_LOCK   2
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/* idle state that device can send */
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static inline void idle(void)
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{
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    clock_hi();
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    data_hi();
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}
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extern uint8_t ps2_error;
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/* host role */
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void ps2_host_init(void);
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uint8_t ps2_host_send(uint8_t data);
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uint8_t ps2_host_recv_response(void);
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uint8_t ps2_host_recv(void);
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void ps2_host_set_led(uint8_t usb_led);
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/* device role */
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/* inhibit device to send */
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static inline void inhibit(void)
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{
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    clock_lo();
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    data_hi();
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}
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#endif
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						 | 
				
			
			
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										179
									
								
								protocol/ps2_busywait.c
									
										
									
									
									
										Normal file
									
								
							
							
						
						
									
										179
									
								
								protocol/ps2_busywait.c
									
										
									
									
									
										Normal file
									
								
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			@ -0,0 +1,179 @@
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/*
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Copyright 2010,2011,2012,2013 Jun WAKO <wakojun@gmail.com>
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This software is licensed with a Modified BSD License.
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All of this is supposed to be Free Software, Open Source, DFSG-free,
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GPL-compatible, and OK to use in both free and proprietary applications.
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Additions and corrections to this file are welcome.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright
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  notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright
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  notice, this list of conditions and the following disclaimer in
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  the documentation and/or other materials provided with the
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  distribution.
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* Neither the name of the copyright holders nor the names of
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  contributors may be used to endorse or promote products derived
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  from this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <stdbool.h>
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#include <util/delay.h>
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#include "ps2.h"
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#include "debug.h"
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/*
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 * PS/2 protocol busywait version
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 */
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#define WAIT(stat, us, err) do { \
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    if (!wait_##stat(us)) { \
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        ps2_error = err; \
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        goto ERROR; \
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    } \
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} while (0)
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uint8_t ps2_error = PS2_ERR_NONE;
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void ps2_host_init(void)
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{
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    // POR(150-2000ms) plus BAT(300-500ms) may take 2.5sec([3]p.20)
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    _delay_ms(2500);
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    inhibit();
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}
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uint8_t ps2_host_send(uint8_t data)
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{
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    uint8_t res = 0;
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    bool parity = true;
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    ps2_error = PS2_ERR_NONE;
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    /* terminate a transmission if we have */
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    inhibit();
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    _delay_us(200); // at least 100us
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    /* start bit [1] */
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    data_lo();
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    clock_hi();
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    WAIT(clock_lo, 20000, 10);   // may take 15ms at most until device starts clocking
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    /* data [2-9] */
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    for (uint8_t i = 0; i < 8; i++) {
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        _delay_us(15);
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        if (data&(1<<i)) {
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            parity = !parity;
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            data_hi();
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        } else {
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            data_lo();
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        }
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        WAIT(clock_hi, 50, 2);
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        WAIT(clock_lo, 50, 3);
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    }
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    /* parity [10] */
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    _delay_us(15);
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    if (parity) { data_hi(); } else { data_lo(); }
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    WAIT(clock_hi, 50, 4);
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    WAIT(clock_lo, 50, 5);
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    /* stop bit [11] */
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    _delay_us(15);
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    data_hi();
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    /* ack [12] */
 | 
			
		||||
    WAIT(data_lo, 50, 6);
 | 
			
		||||
    WAIT(clock_lo, 50, 7);
 | 
			
		||||
 | 
			
		||||
    /* wait for idle state */
 | 
			
		||||
    WAIT(clock_hi, 50, 8);
 | 
			
		||||
    WAIT(data_hi, 50, 9);
 | 
			
		||||
 | 
			
		||||
    res = ps2_host_recv_response();
 | 
			
		||||
ERROR:
 | 
			
		||||
    inhibit();
 | 
			
		||||
    return res;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/* receive data when host want else inhibit communication */
 | 
			
		||||
uint8_t ps2_host_recv_response(void)
 | 
			
		||||
{
 | 
			
		||||
    // TODO:
 | 
			
		||||
    // Command might take 20ms to response([3]p.21)
 | 
			
		||||
    // TrackPoint might take 25ms ([5]2.7)
 | 
			
		||||
    uint8_t data = 0;
 | 
			
		||||
    uint8_t try = 200;
 | 
			
		||||
    while (try-- && (data = ps2_host_recv())) ;
 | 
			
		||||
    return data;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/* send LED state to keyboard */
 | 
			
		||||
void ps2_host_set_led(uint8_t led)
 | 
			
		||||
{
 | 
			
		||||
    ps2_host_send(0xED);
 | 
			
		||||
    ps2_host_send(led);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/* called after start bit comes */
 | 
			
		||||
uint8_t ps2_host_recv(void)
 | 
			
		||||
{
 | 
			
		||||
    uint8_t data = 0;
 | 
			
		||||
    bool parity = true;
 | 
			
		||||
    ps2_error = PS2_ERR_NONE;
 | 
			
		||||
 | 
			
		||||
    /* release lines(idle state) */
 | 
			
		||||
    idle();
 | 
			
		||||
 | 
			
		||||
    /* start bit [1] */
 | 
			
		||||
    WAIT(clock_lo, 100, 1); // TODO: this is enough?
 | 
			
		||||
    WAIT(data_lo, 1, 2);
 | 
			
		||||
    WAIT(clock_hi, 50, 3);
 | 
			
		||||
 | 
			
		||||
    /* data [2-9] */
 | 
			
		||||
    for (uint8_t i = 0; i < 8; i++) {
 | 
			
		||||
        WAIT(clock_lo, 50, 4);
 | 
			
		||||
        if (data_in()) {
 | 
			
		||||
            parity = !parity;
 | 
			
		||||
            data |= (1<<i);
 | 
			
		||||
        }
 | 
			
		||||
        WAIT(clock_hi, 50, 5);
 | 
			
		||||
    }
 | 
			
		||||
 | 
			
		||||
    /* parity [10] */
 | 
			
		||||
    WAIT(clock_lo, 50, 6);
 | 
			
		||||
    if (data_in() != parity) {
 | 
			
		||||
        ps2_error = PS2_ERR_PARITY;
 | 
			
		||||
        goto ERROR;
 | 
			
		||||
    }
 | 
			
		||||
    WAIT(clock_hi, 50, 7);
 | 
			
		||||
 | 
			
		||||
    /* stop bit [11] */
 | 
			
		||||
    WAIT(clock_lo, 50, 8);
 | 
			
		||||
    WAIT(data_hi, 1, 9);
 | 
			
		||||
    WAIT(clock_hi, 50, 10);
 | 
			
		||||
 | 
			
		||||
    inhibit();
 | 
			
		||||
    return data;
 | 
			
		||||
ERROR:
 | 
			
		||||
    if (ps2_error > PS2_ERR_STARTBIT3) {
 | 
			
		||||
        printf("x%02X\n", ps2_error);
 | 
			
		||||
    }
 | 
			
		||||
    inhibit();
 | 
			
		||||
    return 0;
 | 
			
		||||
}
 | 
			
		||||
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		Reference in a new issue