// SPDX-License-Identifier: GPL-2.0-only/* * PS/2 driver library * * Copyright (c) 1999-2002 Vojtech Pavlik * Copyright (c) 2004 Dmitry Torokhov */ #include <linux/delay.h>#include <linux/export.h>#include <linux/module.h>#include <linux/sched.h>#include <linux/interrupt.h>#include <linux/input.h>#include <linux/kmsan-checks.h>#include <linux/serio.h>#include <linux/i8042.h>#include <linux/libps2.h> #define DRIVER_DESC "PS/2 driver library" #define PS2_CMD_SETSCALE11 0x00e6#define PS2_CMD_SETRES 0x10e8#define PS2_CMD_EX_SETLEDS 0x20eb#define PS2_CMD_SETLEDS 0x10ed#define PS2_CMD_GETID 0x02f2#define PS2_CMD_SETREP 0x10f3 /* Set repeat rate/set report rate */#define PS2_CMD_RESET_BAT 0x02ff #define PS2_RET_BAT 0xaa#define PS2_RET_ID 0x00#define PS2_RET_ACK 0xfa#define PS2_RET_NAK 0xfe#define PS2_RET_ERR 0xfc #define PS2_FLAG_ACK BIT(0) /* Waiting for ACK/NAK */#define PS2_FLAG_CMD BIT(1) /* Waiting for a command to finish */#define PS2_FLAG_CMD1 BIT(2) /* Waiting for the first byte of command response */#define PS2_FLAG_WAITID BIT(3) /* Command executing is GET ID */#define PS2_FLAG_NAK BIT(4) /* Last transmission was NAKed */#define PS2_FLAG_PASS_NOACK BIT(5) /* Pass non-ACK byte to receive handler */ static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout, unsigned int max_attempts) __releases(&ps2dev->serio->lock) __acquires(&ps2dev->serio->lock){ int attempt = 0; int error; lockdep_assert_held(&ps2dev->serio->lock); do { ps2dev->nak = 1; ps2dev->flags |= PS2_FLAG_ACK; serio_continue_rx(ps2dev->serio); error = serio_write(ps2dev->serio, byte); if (error) dev_dbg(&ps2dev->serio->dev, "failed to write %#02x: %d\n", byte, error); else wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_ACK), msecs_to_jiffies(timeout)); serio_pause_rx(ps2dev->serio); } while (ps2dev->nak == PS2_RET_NAK && ++attempt < max_attempts); ps2dev->flags &= ~PS2_FLAG_ACK; if (!error) { switch (ps2dev->nak) { case 0: break; case PS2_RET_NAK: error = -EAGAIN; break; case PS2_RET_ERR: error = -EPROTO; break; default: error = -EIO; break; } } if (error || attempt > 1) dev_dbg(&ps2dev->serio->dev, "%02x - %d (%x), attempt %d\n", byte, error, ps2dev->nak, attempt); return error;} /** * ps2_sendbyte - sends a byte to the device and wait for acknowledgement * @ps2dev: a PS/2 device to send the data to * @byte: data to be sent to the device * @timeout: timeout for sending the data and receiving an acknowledge * * The function doesn't handle retransmission, the caller is expected to handle * it when needed. * * ps2_sendbyte() can only be called from a process context. */int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout){ int retval; guard(serio_pause_rx)(ps2dev->serio); retval = ps2_do_sendbyte(ps2dev, byte, timeout, 1); dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak); return retval;}EXPORT_SYMBOL(ps2_sendbyte); /** * ps2_begin_command - mark beginning of execution of a complex command * @ps2dev: a PS/2 device executing the command * * Serializes a complex/compound command. Once command is finished * ps2_end_command() should be called. */void ps2_begin_command(struct ps2dev *ps2dev){ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; mutex_lock(m);}EXPORT_SYMBOL(ps2_begin_command); /** * ps2_end_command - mark end of execution of a complex command * @ps2dev: a PS/2 device executing the command */void ps2_end_command(struct ps2dev *ps2dev){ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; mutex_unlock(m);}EXPORT_SYMBOL(ps2_end_command); /** * ps2_drain - waits for device to transmit requested number of bytes * and discards them * @ps2dev: the PS/2 device that should be drained * @maxbytes: maximum number of bytes to be drained * @timeout: time to drain the device */void ps2_drain(struct ps2dev *ps2dev, size_t maxbytes, unsigned int timeout){ if (WARN_ON(maxbytes > sizeof(ps2dev->cmdbuf))) maxbytes = sizeof(ps2dev->cmdbuf); ps2_begin_command(ps2dev); scoped_guard(serio_pause_rx, ps2dev->serio) { ps2dev->flags = PS2_FLAG_CMD; ps2dev->cmdcnt = maxbytes; } wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD), msecs_to_jiffies(timeout)); ps2_end_command(ps2dev);}EXPORT_SYMBOL(ps2_drain); /** * ps2_is_keyboard_id - checks received ID byte against the list of * known keyboard IDs * @id_byte: data byte that should be checked */bool ps2_is_keyboard_id(u8 id_byte){ static const u8 keyboard_ids[] = { 0xab, /* Regular keyboards */ 0xac, /* NCD Sun keyboard */ 0x2b, /* Trust keyboard, translated */ 0x5d, /* Trust keyboard */ 0x60, /* NMB SGI keyboard, translated */ 0x47, /* NMB SGI keyboard */ }; return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL;}EXPORT_SYMBOL(ps2_is_keyboard_id); /* * ps2_adjust_timeout() is called after receiving 1st byte of command * response and tries to reduce remaining timeout to speed up command * completion. */static int ps2_adjust_timeout(struct ps2dev *ps2dev, unsigned int command, unsigned int timeout){ switch (command) { case PS2_CMD_RESET_BAT: /* * Device has sent the first response byte after * reset command, reset is thus done, so we can * shorten the timeout. * The next byte will come soon (keyboard) or not * at all (mouse). */ if (timeout > msecs_to_jiffies(100)) timeout = msecs_to_jiffies(100); break; case PS2_CMD_GETID: /* * Microsoft Natural Elite keyboard responds to * the GET ID command as it were a mouse, with * a single byte. Fail the command so atkbd will * use alternative probe to detect it. */ if (ps2dev->cmdbuf[1] == 0xaa) { scoped_guard(serio_pause_rx, ps2dev->serio) ps2dev->flags = 0; timeout = 0; } /* * If device behind the port is not a keyboard there * won't be 2nd byte of ID response. */ if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { scoped_guard(serio_pause_rx, ps2dev->serio) ps2dev->flags = ps2dev->cmdcnt = 0; timeout = 0; } break; default: break; } return timeout;} /** * __ps2_command - send a command to PS/2 device * @ps2dev: the PS/2 device that should execute the command * @param: a buffer containing parameters to be sent along with the command, * or place where the results of the command execution will be deposited, * or both * @command: command word that encodes the command itself, as well as number of * additional parameter bytes that should be sent to the device and expected * length of the command response * * Not serialized. Callers should use ps2_begin_command() and ps2_end_command() * to ensure proper serialization for complex commands. */int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command){ unsigned int timeout; unsigned int send = (command >> 12) & 0xf; unsigned int receive = (command >> 8) & 0xf; int rc; int i; u8 send_param[16]; if (WARN_ON(receive > sizeof(ps2dev->cmdbuf))) return -EINVAL; if (WARN_ON(send && !param)) return -EINVAL; memcpy(send_param, param, send); /* * Not using guard notation because we need to break critical * section below while waiting for the response. */ serio_pause_rx(ps2dev->serio); ps2dev->cmdcnt = receive; switch (command) { case PS2_CMD_GETID: /* * Some mice do not ACK the "get ID" command, prepare to * handle this. */ ps2dev->flags = PS2_FLAG_WAITID; break; case PS2_CMD_SETLEDS: case PS2_CMD_EX_SETLEDS: case PS2_CMD_SETREP: ps2dev->flags = PS2_FLAG_PASS_NOACK; break; default: ps2dev->flags = 0; break; } if (receive) { /* Indicate that we expect response to the command. */ ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; if (param) for (i = 0; i < receive; i++) ps2dev->cmdbuf[(receive - 1) - i] = param[i]; } /* * Some devices (Synaptics) perform the reset before * ACKing the reset command, and so it can take a long * time before the ACK arrives. */ timeout = command == PS2_CMD_RESET_BAT ? 1000 : 200; rc = ps2_do_sendbyte(ps2dev, command & 0xff, timeout, 2); if (rc) goto out_reset_flags; /* Send command parameters, if any. */ for (i = 0; i < send; i++) { rc = ps2_do_sendbyte(ps2dev, param[i], 200, 2); if (rc) goto out_reset_flags; } serio_continue_rx(ps2dev->serio); /* * The reset command takes a long time to execute. */ timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); timeout = wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD1), timeout); if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) { timeout = ps2_adjust_timeout(ps2dev, command, timeout); wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD), timeout); } serio_pause_rx(ps2dev->serio); if (param) { for (i = 0; i < receive; i++) param[i] = ps2dev->cmdbuf[(receive - 1) - i]; kmsan_unpoison_memory(param, receive); } if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) { rc = -EPROTO; goto out_reset_flags; } rc = 0; out_reset_flags: ps2dev->flags = 0; serio_continue_rx(ps2dev->serio); dev_dbg(&ps2dev->serio->dev, "%02x [%*ph] - %x/%08lx [%*ph]\n", command & 0xff, send, send_param, ps2dev->nak, ps2dev->flags, receive, param ?: send_param); /* * ps_command() handles resends itself, so do not leak -EAGAIN * to the callers. */ return rc != -EAGAIN ? rc : -EPROTO;}EXPORT_SYMBOL(__ps2_command); /** * ps2_command - send a command to PS/2 device * @ps2dev: the PS/2 device that should execute the command * @param: a buffer containing parameters to be sent along with the command, * or place where the results of the command execution will be deposited, * or both * @command: command word that encodes the command itself, as well as number of * additional parameter bytes that should be sent to the device and expected * length of the command response * * Note: ps2_command() serializes the command execution so that only one * command can be executed at a time for either individual port or the entire * 8042 controller. */int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command){ int rc; ps2_begin_command(ps2dev); rc = __ps2_command(ps2dev, param, command); ps2_end_command(ps2dev); return rc;}EXPORT_SYMBOL(ps2_command); /** * ps2_sliced_command - sends an extended PS/2 command to a mouse * @ps2dev: the PS/2 device that should execute the command * @command: command byte * * The command is sent using "sliced" syntax understood by advanced devices, * such as Logitech or Synaptics touchpads. The command is encoded as: * 0xE6 0xE8 rr 0xE8 ss 0xE8 tt 0xE8 uu where (rr*64)+(ss*16)+(tt*4)+uu * is the command. */int ps2_sliced_command(struct ps2dev *ps2dev, u8 command){ int i; int retval; ps2_begin_command(ps2dev); retval = __ps2_command(ps2dev, NULL, PS2_CMD_SETSCALE11); if (retval) goto out; for (i = 6; i >= 0; i -= 2) { u8 d = (command >> i) & 3; retval = __ps2_command(ps2dev, &d, PS2_CMD_SETRES); if (retval) break; } out: dev_dbg(&ps2dev->serio->dev, "%02x - %d\n", command, retval); ps2_end_command(ps2dev); return retval;}EXPORT_SYMBOL(ps2_sliced_command); /** * ps2_init - initializes ps2dev structure * @ps2dev: structure to be initialized * @serio: serio port associated with the PS/2 device * @pre_receive_handler: validation handler to check basic communication state * @receive_handler: main protocol handler * * Prepares ps2dev structure for use in drivers for PS/2 devices. */void ps2_init(struct ps2dev *ps2dev, struct serio *serio, ps2_pre_receive_handler_t pre_receive_handler, ps2_receive_handler_t receive_handler){ ps2dev->pre_receive_handler = pre_receive_handler; ps2dev->receive_handler = receive_handler; mutex_init(&ps2dev->cmd_mutex); lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); init_waitqueue_head(&ps2dev->wait); ps2dev->serio = serio; serio_set_drvdata(serio, ps2dev);}EXPORT_SYMBOL(ps2_init); /* * ps2_handle_response() stores device's response to a command and notifies * the process waiting for completion of the command. Note that there is a * distinction between waiting for the first byte of the response, and * waiting for subsequent bytes. It is done so that callers could shorten * timeouts once first byte of response is received. */static void ps2_handle_response(struct ps2dev *ps2dev, u8 data){ if (ps2dev->cmdcnt) ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; if (ps2dev->flags & PS2_FLAG_CMD1) { ps2dev->flags &= ~PS2_FLAG_CMD1; if (ps2dev->cmdcnt) wake_up(&ps2dev->wait); } if (!ps2dev->cmdcnt) { ps2dev->flags &= ~PS2_FLAG_CMD; wake_up(&ps2dev->wait); }} /* * ps2_handle_ack() processes ACK/NAK of a command from a PS/2 device, * possibly applying workarounds for mice not acknowledging the "get ID" * command. */static void ps2_handle_ack(struct ps2dev *ps2dev, u8 data){ switch (data) {Lines 1–500 of 620. Load more
// SPDX-License-Identifier: GPL-2.0-only /* * PS/2 driver library * * Copyright (c) 1999-2002 Vojtech Pavlik * Copyright (c) 2004 Dmitry Torokhov */ #include <linux/delay.h> #include <linux/export.h> #include <linux/module.h> #include <linux/sched.h> #include <linux/interrupt.h> #include <linux/input.h> #include <linux/kmsan-checks.h> #include <linux/serio.h> #include <linux/i8042.h> #include <linux/libps2.h> #define DRIVER_DESC "PS/2 driver library" #define PS2_CMD_SETSCALE11 0x00e6 #define PS2_CMD_SETRES 0x10e8 #define PS2_CMD_EX_SETLEDS 0x20eb #define PS2_CMD_SETLEDS 0x10ed #define PS2_CMD_GETID 0x02f2 #define PS2_CMD_SETREP 0x10f3 /* Set repeat rate/set report rate */ #define PS2_CMD_RESET_BAT 0x02ff #define PS2_RET_BAT 0xaa #define PS2_RET_ID 0x00 #define PS2_RET_ACK 0xfa #define PS2_RET_NAK 0xfe #define PS2_RET_ERR 0xfc #define PS2_FLAG_ACK BIT(0) /* Waiting for ACK/NAK */ #define PS2_FLAG_CMD BIT(1) /* Waiting for a command to finish */ #define PS2_FLAG_CMD1 BIT(2) /* Waiting for the first byte of command response */ #define PS2_FLAG_WAITID BIT(3) /* Command executing is GET ID */ #define PS2_FLAG_NAK BIT(4) /* Last transmission was NAKed */ #define PS2_FLAG_PASS_NOACK BIT(5) /* Pass non-ACK byte to receive handler */ static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout, unsigned int max_attempts) __releases(&ps2dev->serio->lock) __acquires(&ps2dev->serio->lock) { int attempt = 0; int error; lockdep_assert_held(&ps2dev->serio->lock); do { ps2dev->nak = 1; ps2dev->flags |= PS2_FLAG_ACK; serio_continue_rx(ps2dev->serio); error = serio_write(ps2dev->serio, byte); if (error) dev_dbg(&ps2dev->serio->dev, "failed to write %#02x: %d\n", byte, error); else wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_ACK), msecs_to_jiffies(timeout)); serio_pause_rx(ps2dev->serio); } while (ps2dev->nak == PS2_RET_NAK && ++attempt < max_attempts); ps2dev->flags &= ~PS2_FLAG_ACK; if (!error) { switch (ps2dev->nak) { case 0: break; case PS2_RET_NAK: error = -EAGAIN; break; case PS2_RET_ERR: error = -EPROTO; break; default: error = -EIO; break; } } if (error || attempt > 1) dev_dbg(&ps2dev->serio->dev, "%02x - %d (%x), attempt %d\n", byte, error, ps2dev->nak, attempt); return error; } /** * ps2_sendbyte - sends a byte to the device and wait for acknowledgement * @ps2dev: a PS/2 device to send the data to * @byte: data to be sent to the device * @timeout: timeout for sending the data and receiving an acknowledge * * The function doesn't handle retransmission, the caller is expected to handle * it when needed. * * ps2_sendbyte() can only be called from a process context. */ int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout) { int retval; guard(serio_pause_rx)(ps2dev->serio); retval = ps2_do_sendbyte(ps2dev, byte, timeout, 1); dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak); return retval; } EXPORT_SYMBOL(ps2_sendbyte); /** * ps2_begin_command - mark beginning of execution of a complex command * @ps2dev: a PS/2 device executing the command * * Serializes a complex/compound command. Once command is finished * ps2_end_command() should be called. */ void ps2_begin_command(struct ps2dev *ps2dev) { struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; mutex_lock(m); } EXPORT_SYMBOL(ps2_begin_command); /** * ps2_end_command - mark end of execution of a complex command * @ps2dev: a PS/2 device executing the command */ void ps2_end_command(struct ps2dev *ps2dev) { struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; mutex_unlock(m); } EXPORT_SYMBOL(ps2_end_command); /** * ps2_drain - waits for device to transmit requested number of bytes * and discards them * @ps2dev: the PS/2 device that should be drained * @maxbytes: maximum number of bytes to be drained * @timeout: time to drain the device */ void ps2_drain(struct ps2dev *ps2dev, size_t maxbytes, unsigned int timeout) { if (WARN_ON(maxbytes > sizeof(ps2dev->cmdbuf))) maxbytes = sizeof(ps2dev->cmdbuf); ps2_begin_command(ps2dev); scoped_guard(serio_pause_rx, ps2dev->serio) { ps2dev->flags = PS2_FLAG_CMD; ps2dev->cmdcnt = maxbytes; } wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD), msecs_to_jiffies(timeout)); ps2_end_command(ps2dev); } EXPORT_SYMBOL(ps2_drain); /** * ps2_is_keyboard_id - checks received ID byte against the list of * known keyboard IDs * @id_byte: data byte that should be checked */ bool ps2_is_keyboard_id(u8 id_byte) { static const u8 keyboard_ids[] = { 0xab, /* Regular keyboards */ 0xac, /* NCD Sun keyboard */ 0x2b, /* Trust keyboard, translated */ 0x5d, /* Trust keyboard */ 0x60, /* NMB SGI keyboard, translated */ 0x47, /* NMB SGI keyboard */ }; return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL; } EXPORT_SYMBOL(ps2_is_keyboard_id); /* * ps2_adjust_timeout() is called after receiving 1st byte of command * response and tries to reduce remaining timeout to speed up command * completion. */ static int ps2_adjust_timeout(struct ps2dev *ps2dev, unsigned int command, unsigned int timeout) { switch (command) { case PS2_CMD_RESET_BAT: /* * Device has sent the first response byte after * reset command, reset is thus done, so we can * shorten the timeout. * The next byte will come soon (keyboard) or not * at all (mouse). */ if (timeout > msecs_to_jiffies(100)) timeout = msecs_to_jiffies(100); break; case PS2_CMD_GETID: /* * Microsoft Natural Elite keyboard responds to * the GET ID command as it were a mouse, with * a single byte. Fail the command so atkbd will * use alternative probe to detect it. */ if (ps2dev->cmdbuf[1] == 0xaa) { scoped_guard(serio_pause_rx, ps2dev->serio) ps2dev->flags = 0; timeout = 0; } /* * If device behind the port is not a keyboard there * won't be 2nd byte of ID response. */ if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { scoped_guard(serio_pause_rx, ps2dev->serio) ps2dev->flags = ps2dev->cmdcnt = 0; timeout = 0; } break; default: break; } return timeout; } /** * __ps2_command - send a command to PS/2 device * @ps2dev: the PS/2 device that should execute the command * @param: a buffer containing parameters to be sent along with the command, * or place where the results of the command execution will be deposited, * or both * @command: command word that encodes the command itself, as well as number of * additional parameter bytes that should be sent to the device and expected * length of the command response * * Not serialized. Callers should use ps2_begin_command() and ps2_end_command() * to ensure proper serialization for complex commands. */ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) { unsigned int timeout; unsigned int send = (command >> 12) & 0xf; unsigned int receive = (command >> 8) & 0xf; int rc; int i; u8 send_param[16]; if (WARN_ON(receive > sizeof(ps2dev->cmdbuf))) return -EINVAL; if (WARN_ON(send && !param)) return -EINVAL; memcpy(send_param, param, send); /* * Not using guard notation because we need to break critical * section below while waiting for the response. */ serio_pause_rx(ps2dev->serio); ps2dev->cmdcnt = receive; switch (command) { case PS2_CMD_GETID: /* * Some mice do not ACK the "get ID" command, prepare to * handle this. */ ps2dev->flags = PS2_FLAG_WAITID; break; case PS2_CMD_SETLEDS: case PS2_CMD_EX_SETLEDS: case PS2_CMD_SETREP: ps2dev->flags = PS2_FLAG_PASS_NOACK; break; default: ps2dev->flags = 0; break; } if (receive) { /* Indicate that we expect response to the command. */ ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; if (param) for (i = 0; i < receive; i++) ps2dev->cmdbuf[(receive - 1) - i] = param[i]; } /* * Some devices (Synaptics) perform the reset before * ACKing the reset command, and so it can take a long * time before the ACK arrives. */ timeout = command == PS2_CMD_RESET_BAT ? 1000 : 200; rc = ps2_do_sendbyte(ps2dev, command & 0xff, timeout, 2); if (rc) goto out_reset_flags; /* Send command parameters, if any. */ for (i = 0; i < send; i++) { rc = ps2_do_sendbyte(ps2dev, param[i], 200, 2); if (rc) goto out_reset_flags; } serio_continue_rx(ps2dev->serio); /* * The reset command takes a long time to execute. */ timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); timeout = wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD1), timeout); if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) { timeout = ps2_adjust_timeout(ps2dev, command, timeout); wait_event_timeout(ps2dev->wait, !(ps2dev->flags & PS2_FLAG_CMD), timeout); } serio_pause_rx(ps2dev->serio); if (param) { for (i = 0; i < receive; i++) param[i] = ps2dev->cmdbuf[(receive - 1) - i]; kmsan_unpoison_memory(param, receive); } if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) { rc = -EPROTO; goto out_reset_flags; } rc = 0; out_reset_flags: ps2dev->flags = 0; serio_continue_rx(ps2dev->serio); dev_dbg(&ps2dev->serio->dev, "%02x [%*ph] - %x/%08lx [%*ph]\n", command & 0xff, send, send_param, ps2dev->nak, ps2dev->flags, receive, param ?: send_param); /* * ps_command() handles resends itself, so do not leak -EAGAIN * to the callers. */ return rc != -EAGAIN ? rc : -EPROTO; } EXPORT_SYMBOL(__ps2_command); /** * ps2_command - send a command to PS/2 device * @ps2dev: the PS/2 device that should execute the command * @param: a buffer containing parameters to be sent along with the command, * or place where the results of the command execution will be deposited, * or both * @command: command word that encodes the command itself, as well as number of * additional parameter bytes that should be sent to the device and expected * length of the command response * * Note: ps2_command() serializes the command execution so that only one * command can be executed at a time for either individual port or the entire * 8042 controller. */ int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) { int rc; ps2_begin_command(ps2dev); rc = __ps2_command(ps2dev, param, command); ps2_end_command(ps2dev); return rc; } EXPORT_SYMBOL(ps2_command); /** * ps2_sliced_command - sends an extended PS/2 command to a mouse * @ps2dev: the PS/2 device that should execute the command * @command: command byte * * The command is sent using "sliced" syntax understood by advanced devices, * such as Logitech or Synaptics touchpads. The command is encoded as: * 0xE6 0xE8 rr 0xE8 ss 0xE8 tt 0xE8 uu where (rr*64)+(ss*16)+(tt*4)+uu * is the command. */ int ps2_sliced_command(struct ps2dev *ps2dev, u8 command) { int i; int retval; ps2_begin_command(ps2dev); retval = __ps2_command(ps2dev, NULL, PS2_CMD_SETSCALE11); if (retval) goto out; for (i = 6; i >= 0; i -= 2) { u8 d = (command >> i) & 3; retval = __ps2_command(ps2dev, &d, PS2_CMD_SETRES); if (retval) break; } out: dev_dbg(&ps2dev->serio->dev, "%02x - %d\n", command, retval); ps2_end_command(ps2dev); return retval; } EXPORT_SYMBOL(ps2_sliced_command); /** * ps2_init - initializes ps2dev structure * @ps2dev: structure to be initialized * @serio: serio port associated with the PS/2 device * @pre_receive_handler: validation handler to check basic communication state * @receive_handler: main protocol handler * * Prepares ps2dev structure for use in drivers for PS/2 devices. */ void ps2_init(struct ps2dev *ps2dev, struct serio *serio, ps2_pre_receive_handler_t pre_receive_handler, ps2_receive_handler_t receive_handler) { ps2dev->pre_receive_handler = pre_receive_handler; ps2dev->receive_handler = receive_handler; mutex_init(&ps2dev->cmd_mutex); lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); init_waitqueue_head(&ps2dev->wait); ps2dev->serio = serio; serio_set_drvdata(serio, ps2dev); } EXPORT_SYMBOL(ps2_init); /* * ps2_handle_response() stores device's response to a command and notifies * the process waiting for completion of the command. Note that there is a * distinction between waiting for the first byte of the response, and * waiting for subsequent bytes. It is done so that callers could shorten * timeouts once first byte of response is received. */ static void ps2_handle_response(struct ps2dev *ps2dev, u8 data) { if (ps2dev->cmdcnt) ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; if (ps2dev->flags & PS2_FLAG_CMD1) { ps2dev->flags &= ~PS2_FLAG_CMD1; if (ps2dev->cmdcnt) wake_up(&ps2dev->wait); } if (!ps2dev->cmdcnt) { ps2dev->flags &= ~PS2_FLAG_CMD; wake_up(&ps2dev->wait); } } /* * ps2_handle_ack() processes ACK/NAK of a command from a PS/2 device, * possibly applying workarounds for mice not acknowledging the "get ID" * command. */ static void ps2_handle_ack(struct ps2dev *ps2dev, u8 data) { switch (data) {