Files
system76-embedded-controller/src/board/system76/common/kbc.c
2024-06-21 18:18:02 -06:00

520 lines
15 KiB
C

// SPDX-License-Identifier: GPL-3.0-only
#include <board/kbc.h>
#include <board/kbscan.h>
#include <board/keymap.h>
#include <common/debug.h>
#include <common/macro.h>
#include <ec/espi.h>
#include <ec/ps2.h>
void kbc_init(void) {
// Disable interrupts
*(KBC.control) = 0;
#if CONFIG_BUS_ESPI
// Set IRQ mode to edge-triggered, 1-cycle pulse width
*(KBC.irq) = BIT(3);
#else
// Set IRQ mode to level-triggered
*(KBC.irq) = 0;
#endif
kbc_reset();
}
void kbc_reset(void) {
// Set "key lock" to disabled
*(KBC.status) = BIT(4);
}
#define KBC_TIMEOUT 1000
// Enable first port
static bool kbc_first = false;
// Enable second port
static bool kbc_second = false;
// Second port input timeout
static uint8_t kbc_second_wait = 0;
// Translate from scancode set 2 to scancode set 1
// for basically no good reason
static bool kbc_translate = true;
// LED state
uint8_t kbc_leds = 0;
// clang-format off
// Values from linux/drivers/input/keyboard/atkbd.c
static const uint16_t kbc_typematic_period[32] = {
33, // 30.0 cps = ~33.33ms
37, // 26.7 cps = ~37.45ms
42, // 24.0 cps = ~41.67ms
46, // 21.8 cps = ~45.87ms
50, // 20.7 cps = ~48.30ms
54, // 18.5 cps = ~54.05ms
58, // 17.1 cps = ~58.48ms
63, // 16.0 cps = ~62.50ms
67, // 15.0 cps = ~66.67ms
75, // 13.3 cps = ~75.19ms
83, // 12.0 cps = ~83.33ms
92, // 10.9 cps = ~91.74ms
100, // 10.0 cps = 100ms
109, // 9.2 cps = ~108.70ms
116, // 8.6 cps = ~116.28ms
125, // 8.0 cps = 125ms
133, // 7.5 cps = ~133.33ms
149, // 6.7 cps = ~149.25ms
167, // 6.0 cps = ~166.67ms
182, // 5.5 cps = ~181.82ms
200, // 5.0 cps = 200ms
217, // 4.6 cps = ~217.39ms
232, // 4.3 cps = ~232.56ms
250, // 4.0 cps = 250ms
270, // 3.7 cps = ~270.27ms
303, // 3.3 cps = ~303.03ms
333, // 3.0 cps = ~333.33ms
370, // 2.7 cps = ~370.37ms
400, // 2.5 cps = 400ms
435, // 2.3 cps = ~434.78ms
470, // 2.1 cps = ~478.19ms
500, // 2.0 cps = 500ms
};
// clang-format on
static uint8_t kbc_buffer[16] = { 0 };
static uint8_t kbc_buffer_head = 0;
static uint8_t kbc_buffer_tail = 0;
static bool kbc_buffer_pop(uint8_t *const scancode) {
if (kbc_buffer_head == kbc_buffer_tail) {
return false;
}
*scancode = kbc_buffer[kbc_buffer_head];
kbc_buffer_head = (kbc_buffer_head + 1U) % ARRAY_SIZE(kbc_buffer);
return true;
}
static bool kbc_buffer_push(const uint8_t *const scancodes, uint8_t len) {
//TODO: make this test more efficient
for (uint8_t i = 0; i < len; i++) {
if ((kbc_buffer_tail + i + 1U) % ARRAY_SIZE(kbc_buffer) == kbc_buffer_head) {
return false;
}
}
for (uint8_t i = 0; i < len; i++) {
kbc_buffer[kbc_buffer_tail] = scancodes[i];
kbc_buffer_tail = (kbc_buffer_tail + 1U) % ARRAY_SIZE(kbc_buffer);
}
return true;
}
bool kbc_scancode(uint16_t key, bool pressed) {
if (!kbc_first)
return true;
if (kbc_translate) {
key = keymap_translate(key);
}
if (!key)
return true;
uint8_t scancodes[3] = { 0, 0, 0 };
uint8_t scancodes_len = 0;
switch (key & 0xFF00) {
case KF_E0:
scancodes[scancodes_len++] = 0xE0;
key &= 0xFF;
// Fall through
case 0x00:
if (!pressed) {
if (kbc_translate) {
key |= 0x80;
} else {
scancodes[scancodes_len++] = 0xF0;
}
}
scancodes[scancodes_len++] = (uint8_t)key;
break;
}
return kbc_buffer_push(scancodes, scancodes_len);
}
enum KbcState {
// Input buffer states
KBC_STATE_NORMAL,
KBC_STATE_WRITE_CONFIG,
KBC_STATE_SET_LEDS,
KBC_STATE_SCANCODE,
KBC_STATE_TYPEMATIC,
KBC_STATE_WRITE_PORT,
KBC_STATE_FIRST_PORT_OUTPUT,
KBC_STATE_SECOND_PORT_OUTPUT,
KBC_STATE_SECOND_PORT_INPUT,
// Output buffer states
KBC_STATE_KEYBOARD,
KBC_STATE_TOUCHPAD,
KBC_STATE_MOUSE,
// After output buffer states
KBC_STATE_IDENTIFY_0,
KBC_STATE_IDENTIFY_1,
KBC_STATE_SELF_TEST,
};
// TODO: state per KBC (we only have one KBC so low priority)
static enum KbcState state = KBC_STATE_NORMAL;
static uint8_t state_data = 0;
static enum KbcState state_next = KBC_STATE_NORMAL;
// Clear output buffer
static void kbc_clear_output(struct Kbc *const kbc) {
*(kbc->control) |= BIT(5);
*(kbc->control) |= BIT(6);
*(kbc->control) &= ~BIT(5);
}
static void kbc_on_input_command(struct Kbc *const kbc, uint8_t data) {
TRACE("kbc cmd: %02X\n", data);
// Controller commands always reset the state
state = KBC_STATE_NORMAL;
// Controller commands clear the output buffer
kbc_clear_output(kbc);
switch (data) {
case 0x20:
TRACE(" read configuration byte\n");
state = KBC_STATE_KEYBOARD;
// Interrupt enable flags
state_data = *kbc->control & 0x03;
// System flag
if (*kbc->status & BIT(2)) {
state_data |= BIT(2);
}
if (!kbc_first) {
state_data |= BIT(4);
}
if (!kbc_second) {
state_data |= BIT(5);
}
if (kbc_translate) {
state_data |= BIT(6);
}
break;
case 0x60:
TRACE(" write configuration byte\n");
state = KBC_STATE_WRITE_CONFIG;
break;
case 0xA7:
TRACE(" disable second port\n");
kbc_second = false;
break;
case 0xA8:
TRACE(" enable second port\n");
kbc_second = true;
break;
case 0xA9:
TRACE(" test second port\n");
// TODO: communicate with touchpad?
state = KBC_STATE_KEYBOARD;
state_data = 0x00;
break;
case 0xAA:
TRACE(" test controller\n");
// Why not pass the test?
state = KBC_STATE_KEYBOARD;
state_data = 0x55;
break;
case 0xAB:
TRACE(" test first port\n");
// We _ARE_ the keyboard, so everything is good.
state = KBC_STATE_KEYBOARD;
state_data = 0x00;
break;
case 0xAD:
TRACE(" disable first port\n");
kbc_first = false;
break;
case 0xAE:
TRACE(" enable first port\n");
kbc_first = true;
break;
case 0xD1:
TRACE(" write port byte\n");
state = KBC_STATE_WRITE_PORT;
break;
case 0xD2:
TRACE(" write first port output\n");
state = KBC_STATE_FIRST_PORT_OUTPUT;
break;
case 0xD3:
TRACE(" write second port output\n");
state = KBC_STATE_SECOND_PORT_OUTPUT;
break;
case 0xD4:
TRACE(" write second port input\n");
state = KBC_STATE_SECOND_PORT_INPUT;
break;
}
}
static void kbc_on_input_data(struct Kbc *const kbc, uint8_t data) {
TRACE("kbc data: %02X\n", data);
switch (state) {
case KBC_STATE_TOUCHPAD:
// Interrupt touchpad command
state = KBC_STATE_NORMAL;
// Fall through
case KBC_STATE_NORMAL:
TRACE(" keyboard command\n");
// Keyboard commands clear output buffer
kbc_clear_output(kbc);
switch (data) {
case 0xED:
TRACE(" set leds\n");
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
state_next = KBC_STATE_SET_LEDS;
break;
case 0xEE:
TRACE(" echo\n");
// Hey, this is easy. I like easy commands
state = KBC_STATE_KEYBOARD;
state_data = 0xEE;
break;
case 0xF0:
TRACE(" get/set scancode\n");
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
state_next = KBC_STATE_SCANCODE;
break;
case 0xF2:
TRACE(" identify keyboard\n");
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
state_next = KBC_STATE_IDENTIFY_0;
break;
case 0xF3:
TRACE(" set typematic rate/delay\n");
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
state_next = KBC_STATE_TYPEMATIC;
break;
case 0xF4:
TRACE(" enable scanning\n");
kbscan_enabled = true;
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case 0xF5:
TRACE(" disable scanning\n");
kbscan_enabled = false;
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case 0xF6:
TRACE(" set default parameters\n");
kbc_leds = 0;
kbscan_repeat_period = 91;
kbscan_repeat_delay = 500;
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case 0xFF:
TRACE(" self test\n");
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
state_next = KBC_STATE_SELF_TEST;
break;
}
break;
case KBC_STATE_WRITE_CONFIG:
TRACE(" write configuration byte\n");
state = KBC_STATE_NORMAL;
// Enable keyboard interrupt
if (data & BIT(0)) {
*kbc->control |= BIT(0);
} else {
*kbc->control &= ~BIT(0);
}
// Enable mouse interrupt
if (data & BIT(1)) {
*kbc->control |= BIT(1);
} else {
*kbc->control &= ~BIT(1);
}
// System flag
if (data & BIT(2)) {
*kbc->status |= BIT(2);
} else {
*kbc->status &= ~BIT(2);
}
kbc_first = (bool)(!(data & BIT(4)));
kbc_second = (bool)(!(data & BIT(5)));
kbc_translate = (bool)(data & BIT(6));
break;
case KBC_STATE_SET_LEDS:
TRACE(" set leds\n");
kbc_leds = data;
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case KBC_STATE_SCANCODE:
TRACE(" get/set scancode\n");
#if LEVEL >= LEVEL_TRACE
switch (data) {
case 0x02:
TRACE(" set scancode set 2\n");
break;
}
#endif
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case KBC_STATE_TYPEMATIC:
TRACE(" set typematic rate/delay\n");
{
// Rate: bits 0-4
uint16_t period = kbc_typematic_period[data & 0x1F];
kbscan_repeat_period = period;
// Delay: bits 5-6
static const uint16_t delay[4] = { 250, 500, 750, 1000 };
uint8_t idx = (data & 0x60) >> 5;
kbscan_repeat_delay = delay[idx];
}
state = KBC_STATE_KEYBOARD;
state_data = 0xFA;
break;
case KBC_STATE_WRITE_PORT:
TRACE(" write port byte\n");
state = KBC_STATE_NORMAL;
break;
case KBC_STATE_FIRST_PORT_OUTPUT:
TRACE(" write first port output\n");
state = KBC_STATE_KEYBOARD;
state_data = data;
break;
case KBC_STATE_SECOND_PORT_OUTPUT:
TRACE(" write second port output\n");
state = KBC_STATE_MOUSE;
state_data = data;
break;
case KBC_STATE_SECOND_PORT_INPUT:
TRACE(" write second port input\n");
state = KBC_STATE_NORMAL;
// Begin write
*(PS2_TOUCHPAD.control) = 0x1D;
// Write the data
*(PS2_TOUCHPAD.data) = data;
// Pull data line low
*(PS2_TOUCHPAD.control) = 0x1C;
// Pull clock line high
*(PS2_TOUCHPAD.control) = 0x1E;
// Set wait timeout of 100 cycles
kbc_second_wait = 100;
break;
}
}
static void kbc_on_output_empty(struct Kbc *const kbc) {
switch (state) {
case KBC_STATE_KEYBOARD:
TRACE("kbc keyboard: %02X\n", state_data);
if (kbc_keyboard(kbc, state_data, KBC_TIMEOUT)) {
state = state_next;
state_next = KBC_STATE_NORMAL;
}
break;
case KBC_STATE_TOUCHPAD:
state_data = *(PS2_TOUCHPAD.data);
// Fall through
case KBC_STATE_MOUSE:
TRACE("kbc mouse: %02X\n", state_data);
if (kbc_mouse(kbc, state_data, KBC_TIMEOUT)) {
state = state_next;
state_next = KBC_STATE_NORMAL;
}
break;
}
switch (state) {
case KBC_STATE_IDENTIFY_0:
state = KBC_STATE_KEYBOARD;
state_data = 0xAB;
state_next = KBC_STATE_IDENTIFY_1;
break;
case KBC_STATE_IDENTIFY_1:
state = KBC_STATE_KEYBOARD;
state_data = 0x83;
break;
case KBC_STATE_SELF_TEST:
// Yep, everything is still good, I promise
state = KBC_STATE_KEYBOARD;
state_data = 0xAA;
break;
}
}
void kbc_event(struct Kbc *const kbc) {
uint8_t sts;
// Read from scancode buffer when possible
if (state == KBC_STATE_NORMAL && kbc_buffer_pop(&state_data)) {
state = KBC_STATE_KEYBOARD;
}
// Read from touchpad when possible
if (kbc_second) {
if (kbc_second_wait > 0) {
// Wait for touchpad write transaction to finish
kbc_second_wait -= 1;
uint8_t sts = *(PS2_TOUCHPAD.status);
*(PS2_TOUCHPAD.status) = sts;
// If transaction is done, stop waiting
if (sts & PSSTS_DONE) {
kbc_second_wait = 0;
}
// If an error happened, clear status, print error, and stop waiting
else if (sts & PSSTS_ALL_ERR) {
ps2_reset(&PS2_TOUCHPAD);
TRACE(" write second port input ERROR %02X\n", sts);
kbc_second_wait = 0;
}
// If a timeout occurs, clear status, print error, and stop waiting
else if (kbc_second_wait == 0) {
ps2_reset(&PS2_TOUCHPAD);
TRACE(" write second port input TIMEOUT\n");
kbc_second_wait = 0;
}
}
if (kbc_second_wait == 0) {
// Attempt to read from touchpad
*(PS2_TOUCHPAD.control) = 0x17;
if (state == KBC_STATE_NORMAL) {
uint8_t sts = *(PS2_TOUCHPAD.status);
*(PS2_TOUCHPAD.status) = sts;
if (sts & PSSTS_DONE) {
state = KBC_STATE_TOUCHPAD;
}
}
}
} else {
ps2_reset(&PS2_TOUCHPAD);
}
// Read command/data while available
sts = kbc_status(kbc);
if (sts & KBC_STS_IBF) {
uint8_t data = kbc_read(kbc);
if (sts & KBC_STS_CMD) {
kbc_on_input_command(kbc, data);
} else {
kbc_on_input_data(kbc, data);
}
}
// Write data if possible
sts = kbc_status(kbc);
if (!(sts & KBC_STS_OBF)) {
kbc_on_output_empty(kbc);
}
}