From fc58d12be416eb51932eec594667ca3181903b9e Mon Sep 17 00:00:00 2001 From: Dmitry Eremin-Solenikov Date: Mon, 18 Oct 2010 09:18:13 -0700 Subject: [PATCH] Input: serio - add support for PS2Mult multiplexer protocol PS2Mult is a simple serial protocol used for multiplexing several PS/2 streams into one serial data stream. It's used e.g. on TQM85xx series of boards. Signed-off-by: Dmitry Eremin-Solenikov Signed-off-by: Dmitry Torokhov --- drivers/input/serio/Kconfig | 9 ++ drivers/input/serio/Makefile | 1 + drivers/input/serio/ps2mult.c | 318 ++++++++++++++++++++++++++++++++++++++++++ include/linux/serio.h | 1 + 4 files changed, 329 insertions(+) create mode 100644 drivers/input/serio/ps2mult.c diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig index 3bfe8fa..6256233 100644 --- a/drivers/input/serio/Kconfig +++ b/drivers/input/serio/Kconfig @@ -226,4 +226,13 @@ config SERIO_AMS_DELTA To compile this driver as a module, choose M here; the module will be called ams_delta_serio. +config SERIO_PS2MULT + tristate "TQC PS/2 multiplexer" + help + Say Y here if you have the PS/2 line multiplexer like the one + present on TQC boads. + + To compile this driver as a module, choose M here: the + module will be called ps2mult. + endif diff --git a/drivers/input/serio/Makefile b/drivers/input/serio/Makefile index 84c80bf..dbbe376 100644 --- a/drivers/input/serio/Makefile +++ b/drivers/input/serio/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_SERIO_GSCPS2) += gscps2.o obj-$(CONFIG_HP_SDC) += hp_sdc.o obj-$(CONFIG_HIL_MLC) += hp_sdc_mlc.o hil_mlc.o obj-$(CONFIG_SERIO_PCIPS2) += pcips2.o +obj-$(CONFIG_SERIO_PS2MULT) += ps2mult.o obj-$(CONFIG_SERIO_MACEPS2) += maceps2.o obj-$(CONFIG_SERIO_LIBPS2) += libps2.o obj-$(CONFIG_SERIO_RAW) += serio_raw.o diff --git a/drivers/input/serio/ps2mult.c b/drivers/input/serio/ps2mult.c new file mode 100644 index 0000000..6bce22e --- /dev/null +++ b/drivers/input/serio/ps2mult.c @@ -0,0 +1,318 @@ +/* + * TQC PS/2 Multiplexer driver + * + * Copyright (C) 2010 Dmitry Eremin-Solenikov + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + */ + + +#include +#include +#include +#include + +MODULE_AUTHOR("Dmitry Eremin-Solenikov "); +MODULE_DESCRIPTION("TQC PS/2 Multiplexer driver"); +MODULE_LICENSE("GPL"); + +#define PS2MULT_KB_SELECTOR 0xA0 +#define PS2MULT_MS_SELECTOR 0xA1 +#define PS2MULT_ESCAPE 0x7D +#define PS2MULT_BSYNC 0x7E +#define PS2MULT_SESSION_START 0x55 +#define PS2MULT_SESSION_END 0x56 + +struct ps2mult_port { + struct serio *serio; + unsigned char sel; + bool registered; +}; + +#define PS2MULT_NUM_PORTS 2 +#define PS2MULT_KBD_PORT 0 +#define PS2MULT_MOUSE_PORT 1 + +struct ps2mult { + struct serio *mx_serio; + struct ps2mult_port ports[PS2MULT_NUM_PORTS]; + + spinlock_t lock; + struct ps2mult_port *in_port; + struct ps2mult_port *out_port; + bool escape; +}; + +/* First MUST come PS2MULT_NUM_PORTS selectors */ +static const unsigned char ps2mult_controls[] = { + PS2MULT_KB_SELECTOR, PS2MULT_MS_SELECTOR, + PS2MULT_ESCAPE, PS2MULT_BSYNC, + PS2MULT_SESSION_START, PS2MULT_SESSION_END, +}; + +static const struct serio_device_id ps2mult_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_PS2MULT, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, ps2mult_serio_ids); + +static void ps2mult_select_port(struct ps2mult *psm, struct ps2mult_port *port) +{ + struct serio *mx_serio = psm->mx_serio; + + serio_write(mx_serio, port->sel); + psm->out_port = port; + dev_dbg(&mx_serio->dev, "switched to sel %02x\n", port->sel); +} + +static int ps2mult_serio_write(struct serio *serio, unsigned char data) +{ + struct serio *mx_port = serio->parent; + struct ps2mult *psm = serio_get_drvdata(mx_port); + struct ps2mult_port *port = serio->port_data; + bool need_escape; + unsigned long flags; + + spin_lock_irqsave(&psm->lock, flags); + + if (psm->out_port != port) + ps2mult_select_port(psm, port); + + need_escape = memchr(ps2mult_controls, data, sizeof(ps2mult_controls)); + + dev_dbg(&serio->dev, + "write: %s%02x\n", need_escape ? "ESC " : "", data); + + if (need_escape) + serio_write(mx_port, PS2MULT_ESCAPE); + + serio_write(mx_port, data); + + spin_unlock_irqrestore(&psm->lock, flags); + + return 0; +} + +static int ps2mult_serio_start(struct serio *serio) +{ + struct ps2mult *psm = serio_get_drvdata(serio->parent); + struct ps2mult_port *port = serio->port_data; + unsigned long flags; + + spin_lock_irqsave(&psm->lock, flags); + port->registered = true; + spin_unlock_irqrestore(&psm->lock, flags); + + return 0; +} + +static void ps2mult_serio_stop(struct serio *serio) +{ + struct ps2mult *psm = serio_get_drvdata(serio->parent); + struct ps2mult_port *port = serio->port_data; + unsigned long flags; + + spin_lock_irqsave(&psm->lock, flags); + port->registered = false; + spin_unlock_irqrestore(&psm->lock, flags); +} + +static int ps2mult_create_port(struct ps2mult *psm, int i) +{ + struct serio *mx_serio = psm->mx_serio; + struct serio *serio; + + serio = kzalloc(sizeof(struct serio), GFP_KERNEL); + if (!serio) + return -ENOMEM; + + strlcpy(serio->name, "TQC PS/2 Multiplexer", sizeof(serio->name)); + snprintf(serio->phys, sizeof(serio->phys), + "%s/port%d", mx_serio->phys, i); + serio->id.type = SERIO_8042; + serio->write = ps2mult_serio_write; + serio->start = ps2mult_serio_start; + serio->stop = ps2mult_serio_stop; + serio->parent = psm->mx_serio; + serio->port_data = &psm->ports[i]; + + psm->ports[i].serio = serio; + + return 0; +} + +static void ps2mult_reset(struct ps2mult *psm) +{ + unsigned long flags; + + spin_lock_irqsave(&psm->lock, flags); + + serio_write(psm->mx_serio, PS2MULT_SESSION_END); + serio_write(psm->mx_serio, PS2MULT_SESSION_START); + + ps2mult_select_port(psm, &psm->ports[PS2MULT_KBD_PORT]); + + spin_unlock_irqrestore(&psm->lock, flags); +} + +static int ps2mult_connect(struct serio *serio, struct serio_driver *drv) +{ + struct ps2mult *psm; + int i; + int error; + + if (!serio->write) + return -EINVAL; + + psm = kzalloc(sizeof(*psm), GFP_KERNEL); + if (!psm) + return -ENOMEM; + + spin_lock_init(&psm->lock); + psm->mx_serio = serio; + + for (i = 0; i < PS2MULT_NUM_PORTS; i++) { + psm->ports[i].sel = ps2mult_controls[i]; + error = ps2mult_create_port(psm, i); + if (error) + goto err_out; + } + + psm->in_port = psm->out_port = &psm->ports[PS2MULT_KBD_PORT]; + + serio_set_drvdata(serio, psm); + error = serio_open(serio, drv); + if (error) + goto err_out; + + ps2mult_reset(psm); + + for (i = 0; i < PS2MULT_NUM_PORTS; i++) { + struct serio *s = psm->ports[i].serio; + + dev_info(&serio->dev, "%s port at %s\n", s->name, serio->phys); + serio_register_port(s); + } + + return 0; + +err_out: + while (--i >= 0) + kfree(psm->ports[i].serio); + kfree(serio); + return error; +} + +static void ps2mult_disconnect(struct serio *serio) +{ + struct ps2mult *psm = serio_get_drvdata(serio); + + /* Note that serio core already take care of children ports */ + serio_write(serio, PS2MULT_SESSION_END); + serio_close(serio); + kfree(psm); + + serio_set_drvdata(serio, NULL); +} + +static int ps2mult_reconnect(struct serio *serio) +{ + struct ps2mult *psm = serio_get_drvdata(serio); + + ps2mult_reset(psm); + + return 0; +} + +static irqreturn_t ps2mult_interrupt(struct serio *serio, + unsigned char data, unsigned int dfl) +{ + struct ps2mult *psm = serio_get_drvdata(serio); + struct ps2mult_port *in_port; + unsigned long flags; + + dev_dbg(&serio->dev, "Received %02x flags %02x\n", data, dfl); + + spin_lock_irqsave(&psm->lock, flags); + + if (psm->escape) { + psm->escape = false; + in_port = psm->in_port; + if (in_port->registered) + serio_interrupt(in_port->serio, data, dfl); + goto out; + } + + switch (data) { + case PS2MULT_ESCAPE: + dev_dbg(&serio->dev, "ESCAPE\n"); + psm->escape = true; + break; + + case PS2MULT_BSYNC: + dev_dbg(&serio->dev, "BSYNC\n"); + psm->in_port = psm->out_port; + break; + + case PS2MULT_SESSION_START: + dev_dbg(&serio->dev, "SS\n"); + break; + + case PS2MULT_SESSION_END: + dev_dbg(&serio->dev, "SE\n"); + break; + + case PS2MULT_KB_SELECTOR: + dev_dbg(&serio->dev, "KB\n"); + psm->in_port = &psm->ports[PS2MULT_KBD_PORT]; + break; + + case PS2MULT_MS_SELECTOR: + dev_dbg(&serio->dev, "MS\n"); + psm->in_port = &psm->ports[PS2MULT_MOUSE_PORT]; + break; + + default: + in_port = psm->in_port; + if (in_port->registered) + serio_interrupt(in_port->serio, data, dfl); + break; + } + + out: + spin_unlock_irqrestore(&psm->lock, flags); + return IRQ_HANDLED; +} + +static struct serio_driver ps2mult_drv = { + .driver = { + .name = "ps2mult", + }, + .description = "TQC PS/2 Multiplexer driver", + .id_table = ps2mult_serio_ids, + .interrupt = ps2mult_interrupt, + .connect = ps2mult_connect, + .disconnect = ps2mult_disconnect, + .reconnect = ps2mult_reconnect, +}; + +static int __init ps2mult_init(void) +{ + return serio_register_driver(&ps2mult_drv); +} + +static void __exit ps2mult_exit(void) +{ + serio_unregister_driver(&ps2mult_drv); +} + +module_init(ps2mult_init); +module_exit(ps2mult_exit); diff --git a/include/linux/serio.h b/include/linux/serio.h index 109b237..e26f478 100644 --- a/include/linux/serio.h +++ b/include/linux/serio.h @@ -198,5 +198,6 @@ static inline void serio_continue_rx(struct serio *serio) #define SERIO_W8001 0x39 #define SERIO_DYNAPRO 0x3a #define SERIO_HAMPSHIRE 0x3b +#define SERIO_PS2MULT 0x3c #endif -- 2.7.4