diff options
Diffstat (limited to 'drivers/input/serio/libps2.c')
-rw-r--r-- | drivers/input/serio/libps2.c | 322 |
1 files changed, 219 insertions, 103 deletions
diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c index 83e9c663aa67..e6a07e68d1ff 100644 --- a/drivers/input/serio/libps2.c +++ b/drivers/input/serio/libps2.c @@ -26,31 +26,79 @@ MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); MODULE_DESCRIPTION("PS/2 driver library"); MODULE_LICENSE("GPL"); +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 waits for acknowledge. - * It doesn't handle retransmission, though it could - because if there - * is a need for retransmissions device has to be replaced anyway. + * It 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, unsigned char byte, int timeout) +int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout) { + int retval; + serio_pause_rx(ps2dev->serio); - ps2dev->nak = 1; - ps2dev->flags |= PS2_FLAG_ACK; - serio_continue_rx(ps2dev->serio); - if (serio_write(ps2dev->serio, byte) == 0) - wait_event_timeout(ps2dev->wait, - !(ps2dev->flags & PS2_FLAG_ACK), - msecs_to_jiffies(timeout)); + retval = ps2_do_sendbyte(ps2dev, byte, timeout, 1); + dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak); - serio_pause_rx(ps2dev->serio); - ps2dev->flags &= ~PS2_FLAG_ACK; serio_continue_rx(ps2dev->serio); - return -ps2dev->nak; + return retval; } EXPORT_SYMBOL(ps2_sendbyte); @@ -75,7 +123,7 @@ EXPORT_SYMBOL(ps2_end_command); * and discards them. */ -void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout) +void ps2_drain(struct ps2dev *ps2dev, size_t maxbytes, unsigned int timeout) { if (maxbytes > sizeof(ps2dev->cmdbuf)) { WARN_ON(1); @@ -102,9 +150,9 @@ EXPORT_SYMBOL(ps2_drain); * known keyboard IDs. */ -int ps2_is_keyboard_id(char id_byte) +bool ps2_is_keyboard_id(u8 id_byte) { - static const char keyboard_ids[] = { + static const u8 keyboard_ids[] = { 0xab, /* Regular keyboards */ 0xac, /* NCD Sun keyboard */ 0x2b, /* Trust keyboard, translated */ @@ -123,49 +171,50 @@ EXPORT_SYMBOL(ps2_is_keyboard_id); * completion. */ -static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) +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_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) { - serio_pause_rx(ps2dev->serio); - ps2dev->flags = 0; - serio_continue_rx(ps2dev->serio); - 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])) { - serio_pause_rx(ps2dev->serio); - ps2dev->flags = ps2dev->cmdcnt = 0; - serio_continue_rx(ps2dev->serio); - timeout = 0; - } - 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) { + serio_pause_rx(ps2dev->serio); + ps2dev->flags = 0; + serio_continue_rx(ps2dev->serio); + timeout = 0; + } - default: - break; + /* + * 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])) { + serio_pause_rx(ps2dev->serio); + ps2dev->flags = ps2dev->cmdcnt = 0; + serio_continue_rx(ps2dev->serio); + timeout = 0; + } + break; + + default: + break; } return timeout; @@ -178,50 +227,60 @@ static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) * ps2_command() can only be called from a process context */ -int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) +int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) { - int timeout; - int send = (command >> 12) & 0xf; - int receive = (command >> 8) & 0xf; - int rc = -1; + unsigned int timeout; + unsigned int send = (command >> 12) & 0xf; + unsigned int receive = (command >> 8) & 0xf; + int rc; int i; + u8 send_param[16]; if (receive > sizeof(ps2dev->cmdbuf)) { WARN_ON(1); - return -1; + return -EINVAL; } if (send && !param) { WARN_ON(1); - return -1; + return -EINVAL; } + memcpy(send_param, param, send); + serio_pause_rx(ps2dev->serio); + ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; ps2dev->cmdcnt = receive; if (receive && param) for (i = 0; i < receive; i++) ps2dev->cmdbuf[(receive - 1) - i] = param[i]; - serio_continue_rx(ps2dev->serio); + + /* Signal that we are sending the command byte */ + ps2dev->flags |= PS2_FLAG_ACK_CMD; /* * Some devices (Synaptics) peform the reset before * ACKing the reset command, and so it can take a long * time before the ACK arrives. */ - if (ps2_sendbyte(ps2dev, command & 0xff, - command == PS2_CMD_RESET_BAT ? 1000 : 200)) { - serio_pause_rx(ps2dev->serio); + timeout = command == PS2_CMD_RESET_BAT ? 1000 : 200; + + rc = ps2_do_sendbyte(ps2dev, command & 0xff, timeout, 2); + if (rc) goto out_reset_flags; - } + + /* Now we are sending command parameters, if any */ + ps2dev->flags &= ~PS2_FLAG_ACK_CMD; for (i = 0; i < send; i++) { - if (ps2_sendbyte(ps2dev, param[i], 200)) { - serio_pause_rx(ps2dev->serio); + 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. */ @@ -243,8 +302,11 @@ int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) for (i = 0; i < receive; i++) param[i] = ps2dev->cmdbuf[(receive - 1) - i]; - if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) + if (ps2dev->cmdcnt && + (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) { + rc = -EPROTO; goto out_reset_flags; + } rc = 0; @@ -252,11 +314,21 @@ int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) ps2dev->flags = 0; serio_continue_rx(ps2dev->serio); - return rc; + 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); -int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) +int ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) { int rc; @@ -269,6 +341,39 @@ int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) EXPORT_SYMBOL(ps2_command); /* + * ps2_sliced_command() sends an extended PS/2 command to the mouse + * 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 */ @@ -286,42 +391,53 @@ EXPORT_SYMBOL(ps2_init); * to properly process ACK/NAK of a command from a PS/2 device. */ -int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) +bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data) { switch (data) { - case PS2_RET_ACK: - ps2dev->nak = 0; + case PS2_RET_ACK: + ps2dev->nak = 0; + break; + + case PS2_RET_NAK: + ps2dev->flags |= PS2_FLAG_NAK; + ps2dev->nak = PS2_RET_NAK; + break; + + case PS2_RET_ERR: + if (ps2dev->flags & PS2_FLAG_NAK) { + ps2dev->flags &= ~PS2_FLAG_NAK; + ps2dev->nak = PS2_RET_ERR; break; + } - case PS2_RET_NAK: - ps2dev->flags |= PS2_FLAG_NAK; - ps2dev->nak = PS2_RET_NAK; + /* + * Workaround for mice which don't ACK the Get ID command. + * These are valid mouse IDs that we recognize. + */ + case 0x00: + case 0x03: + case 0x04: + if (ps2dev->flags & PS2_FLAG_WAITID) { + ps2dev->nak = 0; break; - - case PS2_RET_ERR: - if (ps2dev->flags & PS2_FLAG_NAK) { - ps2dev->flags &= ~PS2_FLAG_NAK; - ps2dev->nak = PS2_RET_ERR; - break; - } - + } + /* Fall through */ + default: /* - * Workaround for mice which don't ACK the Get ID command. - * These are valid mouse IDs that we recognize. + * Do not signal errors if we get unexpected reply while + * waiting for an ACK to the initial (first) command byte: + * the device might not be quiesced yet and continue + * delivering data. + * Note that we reset PS2_FLAG_WAITID flag, so the workaround + * for mice not acknowledging the Get ID command only triggers + * on the 1st byte; if device spews data we really want to see + * a real ACK from it. */ - case 0x00: - case 0x03: - case 0x04: - if (ps2dev->flags & PS2_FLAG_WAITID) { - ps2dev->nak = 0; - break; - } - /* Fall through */ - default: - return 0; + dev_dbg(&ps2dev->serio->dev, "unexpected %#02x\n", data); + ps2dev->flags &= ~PS2_FLAG_WAITID; + return ps2dev->flags & PS2_FLAG_ACK_CMD; } - if (!ps2dev->nak) { ps2dev->flags &= ~PS2_FLAG_NAK; if (ps2dev->cmdcnt) @@ -334,7 +450,7 @@ int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) if (data != PS2_RET_ACK) ps2_handle_response(ps2dev, data); - return 1; + return true; } EXPORT_SYMBOL(ps2_handle_ack); @@ -344,7 +460,7 @@ EXPORT_SYMBOL(ps2_handle_ack); * waiting for completion of the command. */ -int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) +bool ps2_handle_response(struct ps2dev *ps2dev, u8 data) { if (ps2dev->cmdcnt) ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; @@ -360,7 +476,7 @@ int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) wake_up(&ps2dev->wait); } - return 1; + return true; } EXPORT_SYMBOL(ps2_handle_response); |