-#include <lunaix/peripheral/ps2kbd.h>
+#include <hal/acpi/acpi.h>
+#include <hal/ioapic.h>
#include <lunaix/clock.h>
-#include <lunaix/timer.h>
#include <lunaix/common.h>
+#include <lunaix/input.h>
+#include <lunaix/isrm.h>
+#include <lunaix/peripheral/ps2kbd.h>
#include <lunaix/syslog.h>
-#include <hal/acpi/acpi.h>
-#include <hal/ioapic.h>
+#include <lunaix/timer.h>
-#include <hal/cpu.h>
#include <arch/x86/interrupts.h>
+#include <hal/cpu.h>
#include <klibc/string.h>
#include <stdint.h>
#define PS2_DEV_CMD_MAX_ATTEMPTS 5
-LOG_MODULE("PS2KBD");
+LOG_MODULE("i8042");
static struct ps2_cmd_queue cmd_q;
-static struct ps2_key_buffer key_buf;
static struct ps2_kbd_state kbd_state;
-#define KEY_NUM(x) (x + 0x30)
-#define KEY_NPAD(x) ON_KEYPAD(KEY_NUM(x))
+#define KEY_NUM(x) (x + 0x30)
+#define KEY_NPAD(x) ON_KEYPAD(KEY_NUM(x))
// 我们使用 Scancode Set 2
+// clang-format off
+
// 大部分的扫描码（键码）
static kbd_keycode_t scancode_set2[] = {
0, KEY_F9, 0, KEY_F5, KEY_F3, KEY_F1, KEY_F2, KEY_F12, 0, KEY_F10, KEY_F8, KEY_F6,
KEY_NPAD(3), ON_KEYPAD('-'), ON_KEYPAD('*'), KEY_SCRLLK, 0, 0, 0, 0, KEY_F7
};
+// clang-format on
+
+static struct input_device* kbd_idev;
-#define KBD_STATE_KWAIT 0x00
-#define KBD_STATE_KSPECIAL 0x01
-#define KBD_STATE_KRELEASED 0x02
-#define KBD_STATE_CMDPROCS 0x40
+#define KBD_STATE_KWAIT 0x00
+#define KBD_STATE_KSPECIAL 0x01
+#define KBD_STATE_KRELEASED 0x02
+#define KBD_STATE_E012 0x03
+#define KBD_STATE_KRELEASED_E0 0x04
+#define KBD_STATE_CMDPROCS 0x40
-#define KBD_ENABLE_SPIRQ_FIX
+// #define KBD_ENABLE_SPIRQ_FIX
+#define KBD_ENABLE_SPIRQ_FIX2
// #define KBD_DBGLOG
-void intr_ps2_kbd_handler(const isr_param* param);
-static struct kdb_keyinfo_pkt* ps2_keybuffer_next_write();
+void
+intr_ps2_kbd_handler(const isr_param* param);
-void ps2_device_post_cmd(char cmd, char arg) {
+static u8_t
+ps2_issue_cmd_wretry(char cmd, u16_t arg);
+
+void
+ps2_device_post_cmd(char cmd, char arg)
+{
mutex_lock(&cmd_q.mutex);
int index = (cmd_q.queue_ptr + cmd_q.queue_len) % PS2_CMD_QUEUE_SIZE;
if (index == cmd_q.queue_ptr && cmd_q.queue_len) {
return;
}
- struct ps2_cmd *container = &cmd_q.cmd_queue[index];
+ struct ps2_cmd* container = &cmd_q.cmd_queue[index];
container->cmd = cmd;
container->arg = arg;
cmd_q.queue_len++;
mutex_unlock(&cmd_q.mutex);
}
-void ps2_kbd_init() {
+void
+ps2_kbd_init()
+{
memset(&cmd_q, 0, sizeof(cmd_q));
- memset(&key_buf, 0, sizeof(key_buf));
memset(&kbd_state, 0, sizeof(kbd_state));
-
- mutex_init(&cmd_q.mutex);
- mutex_init(&key_buf.mutex);
+ mutex_init(&cmd_q.mutex);
kbd_state.translation_table = scancode_set2;
kbd_state.state = KBD_STATE_KWAIT;
+ kbd_idev = input_add_device("i8042-kbd");
+
acpi_context* acpi_ctx = acpi_get_context();
if (acpi_ctx->fadt.header.rev > 1) {
/*
* 只有当前ACPI版本大于1时，我们才使用FADT的IAPC_BOOT_ARCH去判断8042是否存在。
* 这是一个坑，在ACPI v1中，这个字段是reserved！而这及至ACPI v2才出现。
- * 需要注意：Bochs 和 QEMU 使用的是ACPI v1，而非 v2 （virtualbox好像是v4）
- *
+ * 需要注意：Bochs 和 QEMU 使用的是ACPI v1，而非 v2
+ * （virtualbox好像是v4）
+ *
+ * (2022/6/29)
+ * QEMU在7.0.0版本中，修复了FADT::IAPC_BOOT无法正确提供关于i8042的信息的bug
+ * https://wiki.qemu.org/ChangeLog/7.0#ACPI_.2F_SMBIOS
+ *
* 请看Bochs的bios源码（QEMU的BIOS其实是照抄bochs的，所以也是一个德行。。）：
* https://bochs.sourceforge.io/cgi-bin/lxr/source/bios/rombios32.c#L1314
*/
if (!(acpi_ctx->fadt.boot_arch & IAPC_ARCH_8042)) {
- kprintf(KERROR "No PS/2 controller detected.\n");
- // FUTURE: Some alternative fallback on this? Check PCI bus for USB controller instead?
+ kprintf(KERROR "not found\n");
+ // FUTURE: Some alternative fallback on this? Check PCI bus for USB
+ // controller instead?
return;
}
+ } else {
+ kprintf(KWARN "outdated FADT used, assuming exists.\n");
}
- else {
- kprintf(KWARN "Outdated FADT used, assuming 8042 always exist.\n");
- }
-
+
char result;
-
+
cpu_disable_interrupt();
// 1、禁用任何的PS/2设备
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_PORT1_DISABLE, PS2_NO_ARG);
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_PORT2_DISABLE, PS2_NO_ARG);
-
+
// 2、清空控制器缓冲区
io_inb(PS2_PORT_ENC_DATA);
-
// 3、屏蔽所有PS/2设备（端口1&2）IRQ，并且禁用键盘键码转换功能
result = ps2_issue_cmd(PS2_CMD_READ_CFG, PS2_NO_ARG);
- result = result & ~(PS2_CFG_P1INT | PS2_CFG_P2INT | PS2_CFG_TRANSLATION);
+ result = result & ~(PS2_CFG_P1INT | PS2_CFG_P2INT);
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_WRITE_CFG, result);
// 4、控制器自检
- result = ps2_issue_cmd(PS2_CMD_SELFTEST, PS2_NO_ARG);
+ result = ps2_issue_cmd_wretry(PS2_CMD_SELFTEST, PS2_NO_ARG);
if (result != PS2_RESULT_TEST_OK) {
- kprintf(KERROR "Controller self-test failed.");
- goto done;
+ kprintf(KWARN "controller self-test failed. (%x)\n", result);
+ // goto done;
}
// 5、设备自检（端口1自检，通常是我们的键盘）
- result = ps2_issue_cmd(PS2_CMD_SELFTEST_PORT1, PS2_NO_ARG);
+ result = ps2_issue_cmd_wretry(PS2_CMD_SELFTEST_PORT1, PS2_NO_ARG);
if (result != 0) {
- kprintf(KERROR "Interface test on port 1 failed.");
- goto done;
+ kprintf(KERROR "interface test on port 1 failed. (%x)\n", result);
+ // goto done;
}
+ ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_PORT2_DISABLE, PS2_NO_ARG);
+
// 6、开启位于端口1的 IRQ，并启用端口1。不用理会端口2，那儿一般是鼠标。
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_PORT1_ENABLE, PS2_NO_ARG);
result = ps2_issue_cmd(PS2_CMD_READ_CFG, PS2_NO_ARG);
- result = result | PS2_CFG_P1INT;
+ // 重新设置配置字节，因为控制器自检有可能重置我们先前做的改动。
+ result = (result | PS2_CFG_P1INT) & ~(PS2_CFG_TRANSLATION | PS2_CFG_P2INT);
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, PS2_CMD_WRITE_CFG, result);
// 至此，PS/2控制器和设备已完成初始化，可以正常使用。
- // 将我们的键盘驱动挂载到第204号中断上（已由IOAPIC映射至IRQ#1），
- intr_subscribe(PC_KBD_IV, intr_ps2_kbd_handler);
-
- // 搞一个计时器，将我们的 ps2_process_cmd 挂上去。每隔5毫秒执行排在队头的命令。
+ // 搞一个计时器，将我们的 ps2_process_cmd
+ // 挂上去。每隔5毫秒执行排在队头的命令。
// 为什么只执行队头的命令，而不是全部的命令？
// 因为我们需要保证isr尽量的简短，运行起来快速。而发送这些命令非常的耗时。
timer_run_ms(5, ps2_process_cmd, NULL, TIMER_MODE_PERIODIC);
* 初始化8042，屏蔽了所有中断，IF=0）。
* 当sti后，这些堆积的中断会紧跟着递送进CPU里，导致我们的键盘handler误认为由按键按下，从而将这个毫无意义的数值加入
* 我们的队列中，以供上层读取。
- *
- * 所以，保险的方法是：在初始化后才去设置ioapic，这样一来我们就能有一个稳定的IRQ#1以放心使用。
- */
- uint8_t irq_kbd = ioapic_get_irq(acpi_ctx, PC_AT_IRQ_KBD);
- ioapic_redirect(irq_kbd, PC_KBD_IV, 0, IOAPIC_DELMOD_FIXED);
+ *
+ * 所以，保险的方法是：在初始化后才去设置ioapic，这样一来我们就能有一个稳定的IRQ#1以放心使用。
+ */
+ isrm_bindirq(PC_AT_IRQ_KBD, intr_ps2_kbd_handler);
-done:
cpu_enable_interrupt();
}
-void ps2_process_cmd(void* arg) {
- /*
+void
+ps2_process_cmd(void* arg)
+{
+ /*
* 检查锁是否已被启用，如果启用，则表明该timer中断发生时，某个指令正在入队。
* 如果是这种情况则跳过，留到下一轮再尝试处理。
* 注意，这里其实是ISR的一部分（timer中断），对于单核CPU来说，ISR等同于单个的原子操作。
- * （因为EFLAGS.IF=0，所有可屏蔽中断被屏蔽。对于NMI的情况，那么就直接算是triple fault了，所以也没有讨论的意义）
+ * （因为EFLAGS.IF=0，所有可屏蔽中断被屏蔽。对于NMI的情况，那么就直接算是triple
+ * fault了，所以也没有讨论的意义）
* 所以，假若我们遵从互斥锁的严格定义（即这里需要阻塞），那么中断将会被阻塞，进而造成死锁。
* 因此，我们这里仅仅进行判断。
* 会不会产生指令堆积？不会，因为指令发送的频率远远低于指令队列清空的频率。在目前，我们发送的唯一指令
}
// 处理队列排头的指令
- struct ps2_cmd *pending_cmd = &cmd_q.cmd_queue[cmd_q.queue_ptr];
- char result;
+ struct ps2_cmd* pending_cmd = &cmd_q.cmd_queue[cmd_q.queue_ptr];
+ u8_t result;
int attempts = 0;
// 尝试将命令发送至PS/2键盘（通过PS/2控制器）
kbd_state.state += KBD_STATE_CMDPROCS;
#endif
attempts++;
- } while(result == PS2_RESULT_NAK && attempts < PS2_DEV_CMD_MAX_ATTEMPTS);
-
+ } while (result == PS2_RESULT_NAK && attempts < PS2_DEV_CMD_MAX_ATTEMPTS);
// XXX: 是否需要处理不成功的指令？
cmd_q.queue_ptr = (cmd_q.queue_ptr + 1) % PS2_CMD_QUEUE_SIZE;
cmd_q.queue_len--;
}
-void kbd_buffer_key_event(kbd_keycode_t key, uint8_t scancode, kbd_kstate_t state) {
- /*
- forgive me on these ugly bit-level tricks,
- I really hate doing branching on these "fliping switch" things
+void
+kbd_buffer_key_event(kbd_keycode_t key, u8_t scancode, kbd_kstate_t state)
+{
+ /*
+ forgive me on these ugly bit-level tricks,
+ I really hate doing branching on these "fliping switch" things
*/
if (key == KEY_CAPSLK) {
kbd_state.key_state ^= KBD_KEY_FCAPSLKED & -state;
if ((key & MODIFR)) {
kbd_kstate_t tmp = (KBD_KEY_FLSHIFT_HELD << (key & 0x00ff));
kbd_state.key_state = (kbd_state.key_state & ~tmp) | (tmp & -state);
- }
- else if (!(key & 0xff00) && (kbd_state.key_state & (KBD_KEY_FLSHIFT_HELD | KBD_KEY_FRSHIFT_HELD))) {
+ } else if (!(key & 0xff00) &&
+ (kbd_state.key_state &
+ (KBD_KEY_FLSHIFT_HELD | KBD_KEY_FRSHIFT_HELD))) {
key = scancode_set2_shift[scancode];
}
state = state | kbd_state.key_state;
- key = key & (0xffdf | -('a' > key || key > 'z' || !(state & KBD_KEY_FCAPSLKED)));
-
- if (!mutex_on_hold(&key_buf.mutex)) {
- struct kdb_keyinfo_pkt* keyevent_pkt = ps2_keybuffer_next_write();
- *keyevent_pkt = (struct kdb_keyinfo_pkt) {
- .keycode = key,
- .scancode = scancode,
- .state = state,
- .timestamp = clock_systime()
- };
- }
+ key = key & (0xffdf |
+ -('a' > key || key > 'z' || !(state & KBD_KEY_FCAPSLKED)));
+
+ struct input_evt_pkt ipkt = { .pkt_type = (state & KBD_KEY_FPRESSED)
+ ? PKT_PRESS
+ : PKT_RELEASE,
+ .scan_code = scancode,
+ .sys_code = (state << 16) | key };
+
+ input_fire_event(kbd_idev, &ipkt);
return;
}
if (state & KBD_KEY_FPRESSED) {
// Ooops, this guy generates irq!
- ps2_device_post_cmd(PS2_KBD_CMD_SETLED, (kbd_state.key_state >> 1) & 0x00ff);
+ ps2_device_post_cmd(PS2_KBD_CMD_SETLED,
+ (kbd_state.key_state >> 1) & 0x00ff);
}
}
-void intr_ps2_kbd_handler(const isr_param* param) {
+void
+intr_ps2_kbd_handler(const isr_param* param)
+{
// This is important! Don't believe me? try comment it out and run on Bochs!
- while (!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL));
-
- // I know you are tempting to move this chunk after the keyboard state check.
- // But DO NOT. This chunk is in right place and right order. Moving it at your own risk
- // This is to ensure we've cleared the output buffer everytime, so it won't pile up across irqs.
- uint8_t scancode = io_inb(PS2_PORT_ENC_DATA);
+ // while (!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL))
+ // ;
+
+ // I know you are tempting to move this chunk after the keyboard state
+ // check. But DO NOT. This chunk is in right place and right order. Moving
+ // it at your own risk This is to ensure we've cleared the output buffer
+ // everytime, so it won't pile up across irqs.
+ u8_t scancode = io_inb(PS2_PORT_ENC_DATA);
kbd_keycode_t key;
- /*
+ /*
* 判断键盘是否处在指令发送状态，防止误触发。（伪输入中断）
* 这是因为我们需要向ps/2设备发送指令（比如控制led灯），而指令会有返回码。
* 这就会有可能导致ps/2控制器在受到我们的命令后（在ps2_process_cmd中），
* 产生IRQ#1中断（虽然说这种情况取决于底层BIOS实现，但还是会发生，比如QEMU和bochs）。
* 所以这就是说，当IRQ#1中断产生时，我们的CPU正处在另一个ISR中。这样就会导致所有的外部中断被缓存在APIC内部的
- * FIFO队列里，进行排队等待（APIC长度为二的队列 {IRR, TMR}；参考 Intel Manual Vol.3A 10.8.4）
+ * FIFO队列里，进行排队等待（APIC长度为二的队列 {IRR, TMR}；参考 Intel
+ * Manual Vol.3A 10.8.4）
* 那么当ps2_process_cmd执行完后（内嵌在#APIC_TIMER_IV），CPU返回EOI给APIC，APIC紧接着将排在队里的IRQ#1发送给CPU
* 造成误触发。也就是说，我们此时读入的scancode实则上是上一个指令的返回代码。
- *
+ *
* Problem 1 (Fixed):
* 但是这种方法有个问题，那就是，假若我们的某一个命令失败了一次，ps/2给出0xfe，我们重传，ps/2收到指令并给出0xfa。
* 那么这样一来，将会由两个连续的IRQ#1产生。而APIC是最多可以缓存两个IRQ，于是我们就会漏掉一个IRQ，依然会误触发。
* Solution:
* 累加掩码 ;)
- *
+ *
* Problem 2:
- * + 这种累加掩码的操作是基于只有一号IRQ产生的中断的假设，万一中间夹杂了别的中断？Race Condition!
- * + 不很稳定x1，假如连续4次发送失败，那么就会导致累加的掩码上溢出，从而导致下述判断失败。
+ * +
+ * 这种累加掩码的操作是基于只有一号IRQ产生的中断的假设，万一中间夹杂了别的中断？Race
+ * Condition!
+ * +
+ * 不很稳定x1，假如连续4次发送失败，那么就会导致累加的掩码上溢出，从而导致下述判断失败。
*/
#ifdef KBD_ENABLE_SPIRQ_FIX
if ((kbd_state.state & 0xc0)) {
}
#endif
+#ifdef KBD_ENABLE_SPIRQ_FIX2
+ if (scancode == PS2_RESULT_ACK || scancode == PS2_RESULT_NAK) {
+ return;
+ }
+#endif
+
#ifdef KBD_DBGLOG
kprintf(KDEBUG "%x\n", scancode & 0xff);
#endif
-
- switch (kbd_state.state)
- {
- case KBD_STATE_KWAIT:
- if (scancode == 0xf0) { // release code
- kbd_state.state = KBD_STATE_KRELEASED;
- } else if (scancode == 0xe0) {
- kbd_state.state = KBD_STATE_KSPECIAL;
- kbd_state.translation_table = scancode_set2_ex;
- } else {
- key = kbd_state.translation_table[scancode];
- kbd_buffer_key_event(key, scancode, KBD_KEY_FPRESSED);
- }
- break;
- case KBD_STATE_KSPECIAL:
- if (scancode == 0xf0) { //release code
- kbd_state.state = KBD_STATE_KRELEASED;
- } else {
+
+ switch (kbd_state.state) {
+ case KBD_STATE_KWAIT:
+ if (scancode == 0xf0) { // release code
+ kbd_state.state = KBD_STATE_KRELEASED;
+ } else if (scancode == 0xe0) {
+ kbd_state.state = KBD_STATE_KSPECIAL;
+ kbd_state.translation_table = scancode_set2_ex;
+ } else {
+ key = kbd_state.translation_table[scancode];
+ kbd_buffer_key_event(key, scancode, KBD_KEY_FPRESSED);
+ }
+ break;
+ case KBD_STATE_KSPECIAL:
+ if (scancode == 0x12) {
+ kbd_state.state = KBD_STATE_E012;
+ } else if (scancode == 0xf0) { // release code
+ kbd_state.state = KBD_STATE_KRELEASED_E0;
+ } else {
+ key = kbd_state.translation_table[scancode];
+ kbd_buffer_key_event(key, scancode, KBD_KEY_FPRESSED);
+
+ kbd_state.state = KBD_STATE_KWAIT;
+ kbd_state.translation_table = scancode_set2;
+ }
+ break;
+ // handle the '0xE0, 0x12, 0xE0, xx' sequence
+ case KBD_STATE_E012:
+ if (scancode == 0xe0) {
+ kbd_state.state = KBD_STATE_KSPECIAL;
+ kbd_state.translation_table = scancode_set2_ex;
+ }
+ break;
+ case KBD_STATE_KRELEASED_E0:
+ if (scancode == 0x12) {
+ goto escape_release;
+ }
+ // fall through
+ case KBD_STATE_KRELEASED:
key = kbd_state.translation_table[scancode];
- kbd_buffer_key_event(key, scancode, KBD_KEY_FPRESSED);
+ kbd_buffer_key_event(key, scancode, KBD_KEY_FRELEASED);
+ escape_release:
+ // reset the translation table to scancode_set2
kbd_state.state = KBD_STATE_KWAIT;
kbd_state.translation_table = scancode_set2;
- }
- break;
- case KBD_STATE_KRELEASED:
- key = kbd_state.translation_table[scancode];
- kbd_buffer_key_event(key, scancode, KBD_KEY_FRELEASED);
-
- // reset the translation table to scancode_set2
- kbd_state.state = KBD_STATE_KWAIT;
- kbd_state.translation_table = scancode_set2;
- break;
-
- default:
- break;
+ break;
+
+ default:
+ break;
}
}
-static uint8_t ps2_issue_cmd(char cmd, uint16_t arg) {
+static u8_t
+ps2_issue_cmd(char cmd, u16_t arg)
+{
ps2_post_cmd(PS2_PORT_CTRL_CMDREG, cmd, arg);
-
+
// 等待PS/2控制器返回。通过轮询（polling）状态寄存器的 bit 0
// 如置位，则表明返回代码此时就在 0x60 IO口上等待读取。
- while(!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL));
+ while (!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL))
+ ;
return io_inb(PS2_PORT_ENC_CMDREG);
}
-static void ps2_post_cmd(uint8_t port, char cmd, uint16_t arg) {
+static u8_t
+ps2_issue_cmd_wretry(char cmd, u16_t arg)
+{
+ u8_t r, c = 0;
+ while ((r = ps2_issue_cmd(cmd, arg)) == PS2_RESULT_NAK && c < 5) {
+ c++;
+ }
+ if (c >= 5) {
+ kprintf(KWARN "max attempt reached.\n");
+ }
+ return r;
+}
+
+static void
+ps2_post_cmd(u8_t port, char cmd, u16_t arg)
+{
// 等待PS/2输入缓冲区清空，这样我们才可以写入命令
- while(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_IFULL);
+ while (io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_IFULL)
+ ;
io_outb(port, cmd);
io_delay(PS2_DELAY);
-
+
if (!(arg & PS2_NO_ARG)) {
// 所有参数一律通过0x60传入。
- io_outb(PS2_PORT_ENC_CMDREG, (uint8_t)(arg & 0x00ff));
+ while (io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_IFULL)
+ ;
+ io_outb(PS2_PORT_ENC_CMDREG, (u8_t)(arg & 0x00ff));
io_delay(PS2_DELAY);
}
}
-static uint8_t ps2_issue_dev_cmd(char cmd, uint16_t arg) {
+static u8_t
+ps2_issue_dev_cmd(char cmd, u16_t arg)
+{
ps2_post_cmd(PS2_PORT_ENC_CMDREG, cmd, arg);
-
+
// 等待PS/2控制器返回。通过轮询（polling）状态寄存器的 bit 0
// 如置位，则表明返回代码此时就在 0x60 IO口上等待读取。
- while(!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL));
+ while (!(io_inb(PS2_PORT_CTRL_STATUS) & PS2_STATUS_OFULL))
+ ;
return io_inb(PS2_PORT_ENC_CMDREG);
-}
-
-int kbd_recv_key(struct kdb_keyinfo_pkt* key_event) {
- if (!key_buf.buffered_len) {
- return 0;
- }
- mutex_lock(&key_buf.mutex);
-
- struct kdb_keyinfo_pkt* pkt_current = &key_buf.buffer[key_buf.read_ptr];
-
- *key_event = *pkt_current;
- key_buf.buffered_len--;
- key_buf.read_ptr = (key_buf.read_ptr + 1) % PS2_KBD_RECV_BUFFER_SIZE;
-
- mutex_unlock(&key_buf.mutex);
- return 1;
-}
-
-static struct kdb_keyinfo_pkt* ps2_keybuffer_next_write() {
- int index = (key_buf.read_ptr + key_buf.buffered_len) % PS2_KBD_RECV_BUFFER_SIZE;
- if (index == key_buf.read_ptr && key_buf.buffered_len) {
- // the reader is lagged so much such that the buffer is full.
- // It is suggested to read from beginning for nearly up-to-date readings.
- key_buf.read_ptr = 0;
- key_buf.buffered_len = index;
- }
- else {
- key_buf.buffered_len++;
- }
- return &key_buf.buffer[index];
}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff