/*
* Berkshire PCI-PC Watchdog Card Driver
*
* (c) Copyright 2003-2007 Wim Van Sebroeck <wim@iguana.be>.
*
* Based on source code of the following authors:
* Ken Hollis <kenji@bitgate.com>,
* Lindsay Harris <lindsay@bluegum.com>,
* Alan Cox <alan@lxorguk.ukuu.org.uk>,
* Matt Domsch <Matt_Domsch@dell.com>,
* Rob Radez <rob@osinvestor.com>
*
* 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.
*
* Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*/
/*
* A bells and whistles driver is available from:
* http://www.kernel.org/pub/linux/kernel/people/wim/pcwd/pcwd_pci/
*
* More info available at
* http://www.berkprod.com/ or http://www.pcwatchdog.com/
*/
/*
* Includes, defines, variables, module parameters, ...
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h> /* For module specific items */
#include <linux/moduleparam.h> /* For new moduleparam's */
#include <linux/types.h> /* For standard types (like size_t) */
#include <linux/errno.h> /* For the -ENODEV/... values */
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/delay.h> /* For mdelay function */
#include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
#include <linux/watchdog.h> /* For the watchdog specific items */
#include <linux/notifier.h> /* For notifier support */
#include <linux/reboot.h> /* For reboot_notifier stuff */
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/fs.h> /* For file operations */
#include <linux/pci.h> /* For pci functions */
#include <linux/ioport.h> /* For io-port access */
#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
#include <linux/io.h> /* For inb/outb/... */
/* Module and version information */
#define WATCHDOG_VERSION "1.03"
#define WATCHDOG_DRIVER_NAME "PCI-PC Watchdog"
#define WATCHDOG_NAME "pcwd_pci"
#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION
/* Stuff for the PCI ID's */
#ifndef PCI_VENDOR_ID_QUICKLOGIC
#define PCI_VENDOR_ID_QUICKLOGIC 0x11e3
#endif
#ifndef PCI_DEVICE_ID_WATCHDOG_PCIPCWD
#define PCI_DEVICE_ID_WATCHDOG_PCIPCWD 0x5030
#endif
/*
* These are the defines that describe the control status bits for the
* PCI-PC Watchdog card.
*/
/* Port 1 : Control Status #1 */
#define WD_PCI_WTRP 0x01 /* Watchdog Trip status */
#define WD_PCI_HRBT 0x02 /* Watchdog Heartbeat */
#define WD_PCI_TTRP 0x04 /* Temperature Trip status */
#define WD_PCI_RL2A 0x08 /* Relay 2 Active */
#define WD_PCI_RL1A 0x10 /* Relay 1 Active */
#define WD_PCI_R2DS 0x40 /* Relay 2 Disable Temperature-trip /
reset */
#define WD_PCI_RLY2 0x80 /* Activate Relay 2 on the board */
/* Port 2 : Control Status #2 */
#define WD_PCI_WDIS 0x10 /* Watchdog Disable */
#define WD_PCI_ENTP 0x20 /* Enable Temperature Trip Reset */
#define WD_PCI_WRSP 0x40 /* Watchdog wrote response */
#define WD_PCI_PCMD 0x80 /* PC has sent command */
/* according to documentation max. time to process a command for the pci
* watchdog card is 100 ms, so we give it 150 ms to do it's job */
#define PCI_COMMAND_TIMEOUT 150
/* Watchdog's internal commands */
#define CMD_GET_STATUS 0x04
#define CMD_GET_FIRMWARE_VERSION 0x08
#define CMD_READ_WATCHDOG_TIMEOUT 0x18
#define CMD_WRITE_WATCHDOG_TIMEOUT 0x19
#define CMD_GET_CLEAR_RESET_COUNT 0x84
/* Watchdog's Dip Switch heartbeat values */
static const int heartbeat_tbl[] = {
5, /* OFF-OFF-OFF = 5 Sec */
10, /* OFF-OFF-ON = 10 Sec */
30, /* OFF-ON-OFF = 30 Sec */
60, /* OFF-ON-ON = 1 Min */
300, /* ON-OFF-OFF = 5 Min */
600, /* ON-OFF-ON = 10 Min */
1800, /* ON-ON-OFF = 30 Min */
3600, /* ON-ON-ON = 1 hour */
};
/* We can only use 1 card due to the /dev/watchdog restriction */
static int cards_found;
/* internal variables */
static int temp_panic;
static unsigned long is_active;
static char expect_release;
/* this is private data for each PCI-PC watchdog card */
static struct {
/* Wether or not the card has a temperature device */
int supports_temp;
/* The card's boot status */
int boot_status;
/* The cards I/O address */
unsigned long io_addr;
/* the lock for io operations */
spinlock_t io_lock;
/* the PCI-device */
struct pci_dev *pdev;
} pcipcwd_private;
/* module parameters */
#define QUIET 0 /* Default */
#define VERBOSE 1 /* Verbose */
#define DEBUG 2 /* print fancy stuff too */
static int debug = QUIET;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
#define WATCHDOG_HEARTBEAT 0 /* default heartbeat =
delay-time from dip-switches */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
"(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* Internal functions
*/
static int send_command(int cmd, int *msb, int *lsb)
{
int got_response, count;
if (debug >= DEBUG)
pr_debug("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x\n",
cmd, *msb, *lsb);
spin_lock(&pcipcwd_private.io_lock);
/* If a command requires data it should be written first.
* Data for commands with 8 bits of data should be written to port 4.
* Commands with 16 bits of data, should be written as LSB to port 4
* and MSB to port 5.
* After the required data has been written then write the command to
* port 6. */
outb_p(*lsb, pcipcwd_private.io_addr + 4);
outb_p(*msb, pcipcwd_private.io_addr + 5);
outb_p(cmd, pcipcwd_private.io_addr + 6);
/* wait till the pci card processed the command, signaled by
* the WRSP bit in port 2 and give it a max. timeout of
* PCI_COMMAND_TIMEOUT to process */
got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
for (count = 0; (count < PCI_COMMAND_TIMEOUT) && (!got_response);
count++) {
mdelay(1);
got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
}
if (debug >= DEBUG) {
if (got_response) {
pr_debug("time to process command was: %d ms\n",
count);
} else {
pr_debug("card did not respond on command!\n");
}
}
if (got_response) {
/* read back response */
*lsb = inb_p(pcipcwd_private.io_addr + 4);
*msb = inb_p(pcipcwd_private.io_addr + 5);
/* clear WRSP bit */
inb_p(pcipcwd_private.io_addr + 6);
if (debug >= DEBUG)
pr_debug("received following data for cmd=0x%02x: msb=0x%02x lsb=0x%02x\n",
cmd, *msb, *lsb);
}
spin_unlock(&pcipcwd_private.io_lock);
return got_response;
}
static inline void pcipcwd_check_temperature_support(void)
{
if (inb_p(pcipcwd_private.io_addr) != 0xF0)
pcipcwd_private.supports_temp = 1;
}
static int pcipcwd_get_option_switches(void)
{
int option_switches;
option_switches = inb_p(pcipcwd_private.io_addr + 3);
return option_switches;
}
static void pcipcwd_show_card_info(void)
{
int got_fw_rev, fw_rev_major, fw_rev_minor;
char fw_ver_str[20]; /* The cards firmware version */
int option_switches;
got_fw_rev = send_command(CMD_GET_FIRMWARE_VERSION, &fw_rev_major,
&fw_rev_minor);
if (got_fw_rev)
sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
else
sprintf(fw_ver_str, "<card no answer>");
/* Get switch settings */
option_switches = pcipcwd_get_option_switches();
pr_info("Found card at port 0x%04x (Firmware: %s) %s temp option\n",
(int) pcipcwd_private.io_addr, fw_ver_str,
(pcipcwd_private.supports_temp ? "with" : "without"));
pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
option_switches,
((option_switches & 0x10) ? "ON" : "OFF"),
((option_switches & 0x08) ? "ON" : "OFF"));
if (pcipcwd_private.boot_status & WDIOF_CARDRESET)
pr_info("Previous reset was caused by the Watchdog card\n");
if (pcipcwd_private.boot_status & WDIOF_OVERHEAT)
pr_info("Card sensed a CPU Overheat\n");
if (pcipcwd_private.boot_status == 0)
pr_info("No previous trip detected - Cold boot or reset\n");
}
static int pcipcwd_start(void)
{
int stat_reg;
spin_lock(&pcipcwd_private.io_lock);
outb_p(0x00, pcipcwd_private.io_addr + 3);
udelay(1000);
stat_reg = inb_p(pcipcwd_private.io_addr + 2);
spin_unlock(&pcipcwd_private.io_lock);
if (stat_reg & WD_PCI_WDIS) {
pr_err("Card timer not enabled\n");
return -1;
}
if (debug >= VERBOSE)
pr_debug("Watchdog started\n");
return 0;
}
static int pcipcwd_stop(void)
{
int stat_reg;
spin_lock(&pcipcwd_private.io_lock);
outb_p(0xA5, pcipcwd_private.io_addr + 3);
udelay(1000);
outb_p(0xA5, pcipcwd_private.io_addr + 3);
udelay(1000);
stat_reg = inb_p(pcipcwd_private.io_addr + 2);
spin_unlock(&pcipcwd_private.io_lock);
if (!(stat_reg & WD_PCI_WDIS)) {
pr_err("Card did not acknowledge disable attempt\n");
return -1;
}
if (debug >= VERBOSE)
pr_debug("Watchdog stopped\n");
return 0;
}
static int pcipcwd_keepalive(void)
{
/* Re-trigger watchdog by writing to port 0 */
spin_lock(&pcipcwd_private.io_lock);
outb_p(0x42, pcipcwd_private.io_addr); /* send out any data */
spin_unlock(&pcipcwd_private.io_lock);
if (debug >= DEBUG)
pr_debug("Watchdog keepalive signal send\n");
return 0;
}
static int pcipcwd_set_heartbeat(int t)
{
int t_msb = t / 256;
int t_lsb = t % 256;
if ((t < 0x0001) || (t > 0xFFFF))
return -EINVAL;
/* Write new heartbeat to watchdog */
send_command(CMD_WRITE_WATCHDOG_TIMEOUT, &t_msb, &t_lsb);
heartbeat = t;
if (debug >= VERBOSE)
pr_debug("New heartbeat: %d\n", heartbeat);
return 0;
}
static int pcipcwd_get_status(int *status)
{
int control_status;
*status = 0;
control_status = inb_p(pcipcwd_private.io_addr + 1);
if (control_status & WD_PCI_WTRP)
*status |= WDIOF_CARDRESET;
if (control_status & WD_PCI_TTRP) {
*status |= WDIOF_OVERHEAT;
if (temp_panic)
panic(KBUILD_MODNAME ": Temperature overheat trip!\n");
}
if (debug >= DEBUG)
pr_debug("Control Status #1: 0x%02x\n", control_status);
return 0;
}
static int pcipcwd_clear_status(void)
{
int control_status;
int msb;
int reset_counter;
if (debug >= VERBOSE)
pr_info("clearing watchdog trip status & LED\n");
control_status = inb_p(pcipcwd_private.io_addr + 1);
if (debug >= DEBUG) {
pr_debug("status was: 0x%02x\n", control_status);
pr_debug("sending: 0x%02x\n",
(control_status & WD_PCI_R2DS) | WD_PCI_WTRP);
}
/* clear trip status & LED and keep mode of relay 2 */
outb_p((control_status & WD_PCI_R2DS) | WD_PCI_WTRP,
pcipcwd_private.io_addr + 1);
/* clear reset counter */
msb = 0;
reset_counter = 0xff;
send_command(CMD_GET_CLEAR_RESET_COUNT, &msb, &reset_counter);
if (debug >= DEBUG) {
pr_debug("reset count was: 0x%02x\n", reset_counter);
}
return 0;
}
static int pcipcwd_get_temperature(int *temperature)
{
*temperature = 0;
if (!pcipcwd_private.supports_temp)
return -ENODEV;
spin_lock(&pcipcwd_private.io_lock);
*temperature = inb_p(pcipcwd_private.io_addr);
spin_unlock(&pcipcwd_private.io_lock);
/*
* Convert celsius to fahrenheit, since this was
* the decided 'standard' for this return value.
*/
*temperature = (*temperature * 9 / 5) + 32;
if (debug >= DEBUG) {
pr_debug("temperature is: %d F\n", *temperature);
}
return 0;
}
static int pcipcwd_get_timeleft(int *time_left)
{
int msb;
int lsb;
/* Read the time that's left before rebooting */
/* Note: if the board is not yet armed then we will read 0xFFFF */
send_command(CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
*time_left = (msb << 8) + lsb;
if (debug >= VERBOSE)
pr_debug("Time left before next reboot: %d\n", *time_left);
return 0;
}
/*
* /dev/watchdog handling
*/
static ssize_t pcipcwd_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if (len) {
if (!nowayout) {
size_t i;
/* note: just in case someone wrote the magic character
* five months ago... */
expect_release = 0;
/* scan to see whether or not we got the
* magic character */
for (i = 0; i != len; i++) {
char c;
if (get_user(c, data + i))
return -EFAULT;
if (c == 'V')
expect_release = 42;
}
}
/* someone wrote to us, we should reload the timer */
pcipcwd_keepalive();
}
return len;
}
static long pcipcwd_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
static const struct watchdog_info ident = {
.options = WDIOF_OVERHEAT |
WDIOF_CARDRESET |
WDIOF_KEEPALIVEPING |
WDIOF_SETTIMEOUT |
WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = WATCHDOG_DRIVER_NAME,
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
{
int status;
pcipcwd_get_status(&status);
return put_user(status, p);
}
case WDIOC_GETBOOTSTATUS:
return put_user(pcipcwd_private.boot_status, p);
case WDIOC_GETTEMP:
{
int temperature;
if (pcipcwd_get_temperature(&temperature))
return -EFAULT;
return put_user(temperature, p);
}
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
if (pcipcwd_stop())
return -EIO;
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
if (pcipcwd_start())
return -EIO;
retval = 0;
}
if (new_options & WDIOS_TEMPPANIC) {
temp_panic = 1;
retval = 0;
}
return retval;
}
case WDIOC_KEEPALIVE:
pcipcwd_keepalive();
return 0;
case WDIOC_SETTIMEOUT:
{
int new_heartbeat;
if (get_user(new_heartbeat, p))
return -EFAULT;
if (pcipcwd_set_heartbeat(new_heartbeat))
return -EINVAL;
pcipcwd_keepalive();
/* Fall */
}
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, p);
case WDIOC_GETTIMELEFT:
{
int time_left;
if (pcipcwd_get_timeleft(&time_left))
return -EFAULT;
return put_user(time_left, p);
}
default:
return -ENOTTY;
}
}
static int pcipcwd_open(struct inode *inode, struct file *file)
{
/* /dev/watchdog can only be opened once */
if (test_and_set_bit(0, &is_active)) {
if (debug >= VERBOSE)
pr_err("Attempt to open already opened device\n");
return -EBUSY;
}
/* Activate */
pcipcwd_start();
pcipcwd_keepalive();
return nonseekable_open(inode, file);
}
static int pcipcwd_release(struct inode *inode, struct file *file)
{
/*
* Shut off the timer.
*/
if (expect_release == 42) {
pcipcwd_stop();
} else {
pr_crit("Unexpected close, not stopping watchdog!\n");
pcipcwd_keepalive();
}
expect_release = 0;
clear_bit(0, &is_active);
return 0;
}
/*
* /dev/temperature handling
*/
static ssize_t pcipcwd_temp_read(struct file *file, char __user *data,
size_t len, loff_t *ppos)
{
int temperature;
if (pcipcwd_get_temperature(&temperature))
return -EFAULT;
if (copy_to_user(data, &temperature, 1))
return -EFAULT;
return 1;
}
static int pcipcwd_temp_open(struct inode *inode, struct file *file)
{
if (!pcipcwd_private.supports_temp)
return -ENODEV;
return nonseekable_open(inode, file);
}
static int pcipcwd_temp_release(struct inode *inode, struct file *file)
{
return 0;
}
/*
* Notify system
*/
static int pcipcwd_notify_sys(struct notifier_block *this, unsigned long code,
void *unused)
{
if (code == SYS_DOWN || code == SYS_HALT)
pcipcwd_stop(); /* Turn the WDT off */
return NOTIFY_DONE;
}
/*
* Kernel Interfaces
*/
static const struct file_operations pcipcwd_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = pcipcwd_write,
.unlocked_ioctl = pcipcwd_ioctl,
.open = pcipcwd_open,
.release = pcipcwd_release,
};
static struct miscdevice pcipcwd_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &pcipcwd_fops,
};
static const struct file_operations pcipcwd_temp_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = pcipcwd_temp_read,
.open = pcipcwd_temp_open,
.release = pcipcwd_temp_release,
};
static struct miscdevice pcipcwd_temp_miscdev = {
.minor = TEMP_MINOR,
.name = "temperature",
.fops = &pcipcwd_temp_fops,
};
static struct notifier_block pcipcwd_notifier = {
.notifier_call = pcipcwd_notify_sys,
};
/*
* Init & exit routines
*/
static int __devinit pcipcwd_card_init(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
int ret = -EIO;
cards_found++;
if (cards_found == 1)
pr_info("%s\n", DRIVER_VERSION);
if (cards_found > 1) {
pr_err("This driver only supports 1 device\n");
return -ENODEV;
}
if (pci_enable_device(pdev)) {
pr_err("Not possible to enable PCI Device\n");
return -ENODEV;
}
if (pci_resource_start(pdev, 0) == 0x0000) {
pr_err("No I/O-Address for card detected\n");
ret = -ENODEV;
goto err_out_disable_device;
}
spin_lock_init(&pcipcwd_private.io_lock);
pcipcwd_private.pdev = pdev;
pcipcwd_private.io_addr = pci_resource_start(pdev, 0);
if (pci_request_regions(pdev, WATCHDOG_NAME)) {
pr_err("I/O address 0x%04x already in use\n",
(int) pcipcwd_private.io_addr);
ret = -EIO;
goto err_out_disable_device;
}
/* get the boot_status */
pcipcwd_get_status(&pcipcwd_private.boot_status);
/* clear the "card caused reboot" flag */
pcipcwd_clear_status();
/* disable card */
pcipcwd_stop();
/* Check whether or not the card supports the temperature device */
pcipcwd_check_temperature_support();
/* Show info about the card itself */
pcipcwd_show_card_info();
/* If heartbeat = 0 then we use the heartbeat from the dip-switches */
if (heartbeat == 0)
heartbeat =
heartbeat_tbl[(pcipcwd_get_option_switches() & 0x07)];
/* Check that the heartbeat value is within it's range ;
* if not reset to the default */
if (pcipcwd_set_heartbeat(heartbeat)) {
pcipcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
WATCHDOG_HEARTBEAT);
}
ret = register_reboot_notifier(&pcipcwd_notifier);
if (ret != 0) {
pr_err("cannot register reboot notifier (err=%d)\n", ret);
goto err_out_release_region;
}
if (pcipcwd_private.supports_temp) {
ret = misc_register(&pcipcwd_temp_miscdev);
if (ret != 0) {
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
TEMP_MINOR, ret);
goto err_out_unregister_reboot;
}
}
ret = misc_register(&pcipcwd_miscdev);
if (ret != 0) {
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto err_out_misc_deregister;
}
pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
return 0;
err_out_misc_deregister:
if (pcipcwd_private.supports_temp)
misc_deregister(&pcipcwd_temp_miscdev);
err_out_unregister_reboot:
unregister_reboot_notifier(&pcipcwd_notifier);
err_out_release_region:
pci_release_regions(pdev);
err_out_disable_device:
pci_disable_device(pdev);
return ret;
}
static void __devexit pcipcwd_card_exit(struct pci_dev *pdev)
{
/* Stop the timer before we leave */
if (!nowayout)
pcipcwd_stop();
/* Deregister */
misc_deregister(&pcipcwd_miscdev);
if (pcipcwd_private.supports_temp)
misc_deregister(&pcipcwd_temp_miscdev);
unregister_reboot_notifier(&pcipcwd_notifier);
pci_release_regions(pdev);
pci_disable_device(pdev);
cards_found--;
}
static DEFINE_PCI_DEVICE_TABLE(pcipcwd_pci_tbl) = {
{ PCI_VENDOR_ID_QUICKLOGIC, PCI_DEVICE_ID_WATCHDOG_PCIPCWD,
PCI_ANY_ID, PCI_ANY_ID, },
{ 0 }, /* End of list */
};
MODULE_DEVICE_TABLE(pci, pcipcwd_pci_tbl);
static struct pci_driver pcipcwd_driver = {
.name = WATCHDOG_NAME,
.id_table = pcipcwd_pci_tbl,
.probe = pcipcwd_card_init,
.remove = __devexit_p(pcipcwd_card_exit),
};
module_pci_driver(pcipcwd_driver);
MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("Berkshire PCI-PC Watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);
