| /* |
| * COMEDI driver for the watchdog subdevice found on some addi-data boards |
| * Copyright (c) 2013 H Hartley Sweeten <hsweeten@visionengravers.com> |
| * |
| * Based on implementations in various addi-data COMEDI drivers. |
| * |
| * COMEDI - Linux Control and Measurement Device Interface |
| * Copyright (C) 1998 David A. Schleef <ds@schleef.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| #include "../comedidev.h" |
| #include "addi_watchdog.h" |
| |
| /* |
| * Register offsets/defines for the addi-data watchdog |
| */ |
| #define ADDI_WDOG_REG 0x00 |
| #define ADDI_WDOG_RELOAD_REG 0x04 |
| #define ADDI_WDOG_TIMEBASE 0x08 |
| #define ADDI_WDOG_CTRL_REG 0x0c |
| #define ADDI_WDOG_CTRL_ENABLE (1 << 0) |
| #define ADDI_WDOG_CTRL_SW_TRIG (1 << 9) |
| #define ADDI_WDOG_STATUS_REG 0x10 |
| #define ADDI_WDOG_STATUS_ENABLED (1 << 0) |
| #define ADDI_WDOG_STATUS_SW_TRIG (1 << 1) |
| |
| struct addi_watchdog_private { |
| unsigned long iobase; |
| unsigned int wdog_ctrl; |
| }; |
| |
| /* |
| * The watchdog subdevice is configured with two INSN_CONFIG instructions: |
| * |
| * Enable the watchdog and set the reload timeout: |
| * data[0] = INSN_CONFIG_ARM |
| * data[1] = timeout reload value |
| * |
| * Disable the watchdog: |
| * data[0] = INSN_CONFIG_DISARM |
| */ |
| static int addi_watchdog_insn_config(struct comedi_device *dev, |
| struct comedi_subdevice *s, |
| struct comedi_insn *insn, |
| unsigned int *data) |
| { |
| struct addi_watchdog_private *spriv = s->private; |
| unsigned int reload; |
| |
| switch (data[0]) { |
| case INSN_CONFIG_ARM: |
| spriv->wdog_ctrl = ADDI_WDOG_CTRL_ENABLE; |
| reload = data[1] & s->maxdata; |
| outl(reload, spriv->iobase + ADDI_WDOG_RELOAD_REG); |
| |
| /* Time base is 20ms, let the user know the timeout */ |
| dev_info(dev->class_dev, "watchdog enabled, timeout:%dms\n", |
| 20 * reload + 20); |
| break; |
| case INSN_CONFIG_DISARM: |
| spriv->wdog_ctrl = 0; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| outl(spriv->wdog_ctrl, spriv->iobase + ADDI_WDOG_CTRL_REG); |
| |
| return insn->n; |
| } |
| |
| static int addi_watchdog_insn_read(struct comedi_device *dev, |
| struct comedi_subdevice *s, |
| struct comedi_insn *insn, |
| unsigned int *data) |
| { |
| struct addi_watchdog_private *spriv = s->private; |
| int i; |
| |
| for (i = 0; i < insn->n; i++) |
| data[i] = inl(spriv->iobase + ADDI_WDOG_STATUS_REG); |
| |
| return insn->n; |
| } |
| |
| static int addi_watchdog_insn_write(struct comedi_device *dev, |
| struct comedi_subdevice *s, |
| struct comedi_insn *insn, |
| unsigned int *data) |
| { |
| struct addi_watchdog_private *spriv = s->private; |
| int i; |
| |
| if (spriv->wdog_ctrl == 0) { |
| dev_warn(dev->class_dev, "watchdog is disabled\n"); |
| return -EINVAL; |
| } |
| |
| /* "ping" the watchdog */ |
| for (i = 0; i < insn->n; i++) { |
| outl(spriv->wdog_ctrl | ADDI_WDOG_CTRL_SW_TRIG, |
| spriv->iobase + ADDI_WDOG_CTRL_REG); |
| } |
| |
| return insn->n; |
| } |
| |
| void addi_watchdog_reset(unsigned long iobase) |
| { |
| outl(0x0, iobase + ADDI_WDOG_CTRL_REG); |
| outl(0x0, iobase + ADDI_WDOG_RELOAD_REG); |
| } |
| EXPORT_SYMBOL_GPL(addi_watchdog_reset); |
| |
| int addi_watchdog_init(struct comedi_subdevice *s, unsigned long iobase) |
| { |
| struct addi_watchdog_private *spriv; |
| |
| spriv = kzalloc(sizeof(*spriv), GFP_KERNEL); |
| if (!spriv) |
| return -ENOMEM; |
| |
| spriv->iobase = iobase; |
| |
| s->private = spriv; |
| |
| s->type = COMEDI_SUBD_TIMER; |
| s->subdev_flags = SDF_WRITEABLE; |
| s->n_chan = 1; |
| s->maxdata = 0xff; |
| s->insn_config = addi_watchdog_insn_config; |
| s->insn_read = addi_watchdog_insn_read; |
| s->insn_write = addi_watchdog_insn_write; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(addi_watchdog_init); |
| |
| static int __init addi_watchdog_module_init(void) |
| { |
| return 0; |
| } |
| module_init(addi_watchdog_module_init); |
| |
| static void __exit addi_watchdog_module_exit(void) |
| { |
| } |
| module_exit(addi_watchdog_module_exit); |
| |
| MODULE_DESCRIPTION("ADDI-DATA Watchdog subdevice"); |
| MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>"); |
| MODULE_LICENSE("GPL"); |