summaryrefslogtreecommitdiff
path: root/ps2_usb/ps2_usart.c
diff options
context:
space:
mode:
Diffstat (limited to 'ps2_usb/ps2_usart.c')
-rw-r--r--ps2_usb/ps2_usart.c325
1 files changed, 0 insertions, 325 deletions
diff --git a/ps2_usb/ps2_usart.c b/ps2_usb/ps2_usart.c
deleted file mode 100644
index e45b94c93b..0000000000
--- a/ps2_usb/ps2_usart.c
+++ /dev/null
@@ -1,325 +0,0 @@
-/*
-Copyright (c) 2010,2011 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.
-*/
-/*
-Primitive PS/2 Library for AVR
-==============================
-Host side is only supported now.
-Synchronous USART is used to receive data by hardware process
-rather than interrupt. During V-USB interrupt runs, CLOCK interrupt
-cannot interpose. In the result it is prone to lost CLOCK edge.
-
-
-I/O control
------------
-High state is asserted by internal pull-up.
-If you have a signaling problem, you may need to have
-external pull-up resisters on CLOCK and DATA line.
-
-
-PS/2 References
----------------
-http://www.computer-engineering.org/ps2protocol/
-http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
-*/
-#include <stdbool.h>
-#include <avr/io.h>
-#include <avr/interrupt.h>
-#include <util/delay.h>
-#include "ps2.h"
-#include "debug.h"
-
-
-#if 0
-#define DEBUGP_INIT() do { DDRC = 0xFF; } while (0)
-#define DEBUGP(x) do { PORTC = x; } while (0)
-#else
-#define DEBUGP_INIT()
-#define DEBUGP(x)
-#endif
-
-#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 void clock_lo(void);
-static inline void clock_hi(void);
-static inline bool clock_in(void);
-static inline void data_lo(void);
-static inline void data_hi(void);
-static inline bool data_in(void);
-static inline uint16_t wait_clock_lo(uint16_t us);
-static inline uint16_t wait_clock_hi(uint16_t us);
-static inline uint16_t wait_data_lo(uint16_t us);
-static inline uint16_t wait_data_hi(uint16_t us);
-static inline void idle(void);
-static inline void inhibit(void);
-#if defined PS2_USE_INT || defined PS2_USE_USART
-static inline uint8_t pbuf_dequeue(void);
-static inline void pbuf_enqueue(uint8_t data);
-#endif
-
-
-void ps2_host_init(void)
-{
- DEBUGP_INIT();
- DEBUGP(0x1);
- idle();
- PS2_USART_INIT();
- PS2_USART_RX_INT_ON();
-}
-
-uint8_t ps2_host_send(uint8_t data)
-{
- uint8_t res = 0;
- bool parity = true;
- ps2_error = PS2_ERR_NONE;
-
- DEBUGP(0x6);
- PS2_USART_OFF();
-
- /* terminate a transmission if we have */
- inhibit();
- _delay_us(100);
-
- /* start bit [1] */
- data_lo();
- clock_hi();
- WAIT(clock_lo, 15000, 1);
- /* data [2-9] */
- for (uint8_t i = 0; i < 8; i++) {
- _delay_us(15);
- if (data&(1<<i)) {
- parity = !parity;
- data_hi();
- } else {
- data_lo();
- }
- WAIT(clock_hi, 50, 2);
- WAIT(clock_lo, 50, 3);
- }
- /* parity [10] */
- _delay_us(15);
- if (parity) { data_hi(); } else { data_lo(); }
- WAIT(clock_hi, 50, 4);
- WAIT(clock_lo, 50, 5);
- /* stop bit [11] */
- _delay_us(15);
- data_hi();
- /* 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:
- idle();
- PS2_USART_INIT();
- PS2_USART_RX_INT_ON();
- return res;
-}
-
-// Do polling data from keyboard to get response to last command.
-uint8_t ps2_host_recv_response(void)
-{
- uint8_t data = 0;
- PS2_USART_INIT();
- PS2_USART_RX_POLL_ON();
- while (!PS2_USART_RX_READY)
- ;
- data = PS2_USART_RX_DATA;
- PS2_USART_OFF();
- DEBUGP(0x9);
- return data;
-}
-
-uint8_t ps2_host_recv(void)
-{
- return pbuf_dequeue();
-}
-
-ISR(PS2_USART_RX_VECT)
-{
- DEBUGP(0x7);
- uint8_t error = PS2_USART_ERROR;
- uint8_t data = PS2_USART_RX_DATA;
- if (error) {
- DEBUGP(error>>2);
- } else {
- pbuf_enqueue(data);
- }
- DEBUGP(0x8);
-}
-
-/* send LED state to keyboard */
-void ps2_host_set_led(uint8_t led)
-{
- // send 0xED then keyboard keeps waiting for next LED data
- // and keyboard does not send any scan codes during waiting.
- // If fail to send LED data keyboard looks like being freezed.
- uint8_t retry = 3;
- while (retry-- && ps2_host_send(PS2_SET_LED) != PS2_ACK)
- ;
- retry = 3;
- while (retry-- && ps2_host_send(led) != PS2_ACK)
- ;
-}
-
-
-/*--------------------------------------------------------------------
- * static functions
- *------------------------------------------------------------------*/
-static inline void clock_lo()
-{
- PS2_CLOCK_PORT &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_DDR |= (1<<PS2_CLOCK_BIT);
-}
-static inline void clock_hi()
-{
- /* input with pull up */
- PS2_CLOCK_DDR &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_PORT |= (1<<PS2_CLOCK_BIT);
-}
-static inline bool clock_in()
-{
- PS2_CLOCK_DDR &= ~(1<<PS2_CLOCK_BIT);
- PS2_CLOCK_PORT |= (1<<PS2_CLOCK_BIT);
- _delay_us(1);
- return PS2_CLOCK_PIN&(1<<PS2_CLOCK_BIT);
-}
-static inline void data_lo()
-{
- PS2_DATA_PORT &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_DDR |= (1<<PS2_DATA_BIT);
-}
-static inline void data_hi()
-{
- /* input with pull up */
- PS2_DATA_DDR &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_PORT |= (1<<PS2_DATA_BIT);
-}
-static inline bool data_in()
-{
- PS2_DATA_DDR &= ~(1<<PS2_DATA_BIT);
- PS2_DATA_PORT |= (1<<PS2_DATA_BIT);
- _delay_us(1);
- return PS2_DATA_PIN&(1<<PS2_DATA_BIT);
-}
-
-static inline uint16_t wait_clock_lo(uint16_t us)
-{
- while (clock_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_clock_hi(uint16_t us)
-{
- while (!clock_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_data_lo(uint16_t us)
-{
- while (data_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-static inline uint16_t wait_data_hi(uint16_t us)
-{
- while (!data_in() && us) { asm(""); _delay_us(1); us--; }
- return us;
-}
-
-/* idle state that device can send */
-static inline void idle(void)
-{
- clock_hi();
- data_hi();
-}
-
-/* inhibit device to send */
-static inline void inhibit(void)
-{
- clock_lo();
- data_hi();
-}
-
-
-/*--------------------------------------------------------------------
- * Ring buffer to store scan codes from keyboard
- *------------------------------------------------------------------*/
-#define PBUF_SIZE 8
-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 (!data)
- return;
-
- 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 {
- debug("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;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-25 13:55:34 +0000