*
*/
-#include <linux/module.h>
+#include <linux/bcd.h>
+#include <linux/i2c.h>
#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtc.h>
#include <linux/slab.h>
+#include <linux/smp_lock.h>
#include <linux/string.h>
-#include <linux/i2c.h>
-#include <linux/rtc.h>
-#include <linux/bcd.h>
+#ifdef CONFIG_RTC_DRV_M41T80_WDT
+#include <linux/fs.h>
+#include <linux/ioctl.h>
+#include <linux/miscdevice.h>
+#include <linux/reboot.h>
+#include <linux/watchdog.h>
+#endif
#define M41T80_REG_SSEC 0
#define M41T80_REG_SEC 1
#define M41T80_ALHOUR_HT (1 << 6) /* HT: Halt Update Bit */
#define M41T80_FLAGS_AF (1 << 6) /* AF: Alarm Flag Bit */
#define M41T80_FLAGS_BATT_LOW (1 << 4) /* BL: Battery Low Bit */
+#define M41T80_WATCHDOG_RB2 (1 << 7) /* RB: Watchdog resolution */
+#define M41T80_WATCHDOG_RB1 (1 << 1) /* RB: Watchdog resolution */
+#define M41T80_WATCHDOG_RB0 (1 << 0) /* RB: Watchdog resolution */
-#define M41T80_FEATURE_HT (1 << 0)
-#define M41T80_FEATURE_BL (1 << 1)
+#define M41T80_FEATURE_HT (1 << 0) /* Halt feature */
+#define M41T80_FEATURE_BL (1 << 1) /* Battery low indicator */
+#define M41T80_FEATURE_SQ (1 << 2) /* Squarewave feature */
+#define M41T80_FEATURE_WD (1 << 3) /* Extra watchdog resolution */
+#define M41T80_FEATURE_SQ_ALT (1 << 4) /* RSx bits are in reg 4 */
#define DRV_VERSION "0.05"
-struct m41t80_chip_info {
- const char *name;
- u8 features;
-};
-
-static const struct m41t80_chip_info m41t80_chip_info_tbl[] = {
- {
- .name = "m41t80",
- .features = 0,
- },
- {
- .name = "m41t81",
- .features = M41T80_FEATURE_HT,
- },
- {
- .name = "m41t81s",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
- {
- .name = "m41t82",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
- {
- .name = "m41t83",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
- {
- .name = "m41st84",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
- {
- .name = "m41st85",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
- {
- .name = "m41st87",
- .features = M41T80_FEATURE_HT | M41T80_FEATURE_BL,
- },
+static const struct i2c_device_id m41t80_id[] = {
+ { "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT },
+ { "m41t65", M41T80_FEATURE_HT | M41T80_FEATURE_WD },
+ { "m41t80", M41T80_FEATURE_SQ },
+ { "m41t81", M41T80_FEATURE_HT | M41T80_FEATURE_SQ},
+ { "m41t81s", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { "m41t82", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { "m41t83", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { "m41st84", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { "m41st85", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { "m41st87", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
+ { }
};
+MODULE_DEVICE_TABLE(i2c, m41t80_id);
struct m41t80_data {
- const struct m41t80_chip_info *chip;
+ u8 features;
struct rtc_device *rtc;
};
return -EIO;
}
- tm->tm_sec = BCD2BIN(buf[M41T80_REG_SEC] & 0x7f);
- tm->tm_min = BCD2BIN(buf[M41T80_REG_MIN] & 0x7f);
- tm->tm_hour = BCD2BIN(buf[M41T80_REG_HOUR] & 0x3f);
- tm->tm_mday = BCD2BIN(buf[M41T80_REG_DAY] & 0x3f);
+ tm->tm_sec = bcd2bin(buf[M41T80_REG_SEC] & 0x7f);
+ tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f);
+ tm->tm_hour = bcd2bin(buf[M41T80_REG_HOUR] & 0x3f);
+ tm->tm_mday = bcd2bin(buf[M41T80_REG_DAY] & 0x3f);
tm->tm_wday = buf[M41T80_REG_WDAY] & 0x07;
- tm->tm_mon = BCD2BIN(buf[M41T80_REG_MON] & 0x1f) - 1;
+ tm->tm_mon = bcd2bin(buf[M41T80_REG_MON] & 0x1f) - 1;
/* assume 20YY not 19YY, and ignore the Century Bit */
- tm->tm_year = BCD2BIN(buf[M41T80_REG_YEAR]) + 100;
+ tm->tm_year = bcd2bin(buf[M41T80_REG_YEAR]) + 100;
return 0;
}
/* Merge time-data and register flags into buf[0..7] */
buf[M41T80_REG_SSEC] = 0;
buf[M41T80_REG_SEC] =
- BIN2BCD(tm->tm_sec) | (buf[M41T80_REG_SEC] & ~0x7f);
+ bin2bcd(tm->tm_sec) | (buf[M41T80_REG_SEC] & ~0x7f);
buf[M41T80_REG_MIN] =
- BIN2BCD(tm->tm_min) | (buf[M41T80_REG_MIN] & ~0x7f);
+ bin2bcd(tm->tm_min) | (buf[M41T80_REG_MIN] & ~0x7f);
buf[M41T80_REG_HOUR] =
- BIN2BCD(tm->tm_hour) | (buf[M41T80_REG_HOUR] & ~0x3f) ;
+ bin2bcd(tm->tm_hour) | (buf[M41T80_REG_HOUR] & ~0x3f) ;
buf[M41T80_REG_WDAY] =
(tm->tm_wday & 0x07) | (buf[M41T80_REG_WDAY] & ~0x07);
buf[M41T80_REG_DAY] =
- BIN2BCD(tm->tm_mday) | (buf[M41T80_REG_DAY] & ~0x3f);
+ bin2bcd(tm->tm_mday) | (buf[M41T80_REG_DAY] & ~0x3f);
buf[M41T80_REG_MON] =
- BIN2BCD(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f);
+ bin2bcd(tm->tm_mon + 1) | (buf[M41T80_REG_MON] & ~0x1f);
/* assume 20YY not 19YY */
- buf[M41T80_REG_YEAR] = BIN2BCD(tm->tm_year % 100);
+ buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year % 100);
if (i2c_transfer(client->adapter, msgs, 1) != 1) {
dev_err(&client->dev, "write error\n");
struct m41t80_data *clientdata = i2c_get_clientdata(client);
u8 reg;
- if (clientdata->chip->features & M41T80_FEATURE_BL) {
+ if (clientdata->features & M41T80_FEATURE_BL) {
reg = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
seq_printf(seq, "battery\t\t: %s\n",
(reg & M41T80_FLAGS_BATT_LOW) ? "exhausted" : "ok");
wbuf[0] = M41T80_REG_ALARM_MON; /* offset into rtc's regs */
reg[M41T80_REG_ALARM_SEC] |= t->time.tm_sec >= 0 ?
- BIN2BCD(t->time.tm_sec) : 0x80;
+ bin2bcd(t->time.tm_sec) : 0x80;
reg[M41T80_REG_ALARM_MIN] |= t->time.tm_min >= 0 ?
- BIN2BCD(t->time.tm_min) : 0x80;
+ bin2bcd(t->time.tm_min) : 0x80;
reg[M41T80_REG_ALARM_HOUR] |= t->time.tm_hour >= 0 ?
- BIN2BCD(t->time.tm_hour) : 0x80;
+ bin2bcd(t->time.tm_hour) : 0x80;
reg[M41T80_REG_ALARM_DAY] |= t->time.tm_mday >= 0 ?
- BIN2BCD(t->time.tm_mday) : 0x80;
+ bin2bcd(t->time.tm_mday) : 0x80;
if (t->time.tm_mon >= 0)
- reg[M41T80_REG_ALARM_MON] |= BIN2BCD(t->time.tm_mon + 1);
+ reg[M41T80_REG_ALARM_MON] |= bin2bcd(t->time.tm_mon + 1);
else
reg[M41T80_REG_ALARM_DAY] |= 0x40;
t->time.tm_mday = -1;
t->time.tm_mon = -1;
if (!(reg[M41T80_REG_ALARM_SEC] & 0x80))
- t->time.tm_sec = BCD2BIN(reg[M41T80_REG_ALARM_SEC] & 0x7f);
+ t->time.tm_sec = bcd2bin(reg[M41T80_REG_ALARM_SEC] & 0x7f);
if (!(reg[M41T80_REG_ALARM_MIN] & 0x80))
- t->time.tm_min = BCD2BIN(reg[M41T80_REG_ALARM_MIN] & 0x7f);
+ t->time.tm_min = bcd2bin(reg[M41T80_REG_ALARM_MIN] & 0x7f);
if (!(reg[M41T80_REG_ALARM_HOUR] & 0x80))
- t->time.tm_hour = BCD2BIN(reg[M41T80_REG_ALARM_HOUR] & 0x3f);
+ t->time.tm_hour = bcd2bin(reg[M41T80_REG_ALARM_HOUR] & 0x3f);
if (!(reg[M41T80_REG_ALARM_DAY] & 0x80))
- t->time.tm_mday = BCD2BIN(reg[M41T80_REG_ALARM_DAY] & 0x3f);
+ t->time.tm_mday = bcd2bin(reg[M41T80_REG_ALARM_DAY] & 0x3f);
if (!(reg[M41T80_REG_ALARM_DAY] & 0x40))
- t->time.tm_mon = BCD2BIN(reg[M41T80_REG_ALARM_MON] & 0x1f) - 1;
+ t->time.tm_mon = bcd2bin(reg[M41T80_REG_ALARM_MON] & 0x1f) - 1;
t->time.tm_year = -1;
t->time.tm_wday = -1;
t->time.tm_yday = -1;
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
- int val;
+ struct m41t80_data *clientdata = i2c_get_clientdata(client);
+ int val, reg_sqw;
+
+ if (!(clientdata->features & M41T80_FEATURE_SQ))
+ return -EINVAL;
- val = i2c_smbus_read_byte_data(client, M41T80_REG_SQW);
+ reg_sqw = M41T80_REG_SQW;
+ if (clientdata->features & M41T80_FEATURE_SQ_ALT)
+ reg_sqw = M41T80_REG_WDAY;
+ val = i2c_smbus_read_byte_data(client, reg_sqw);
if (val < 0)
return -EIO;
val = (val >> 4) & 0xf;
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
- int almon, sqw;
+ struct m41t80_data *clientdata = i2c_get_clientdata(client);
+ int almon, sqw, reg_sqw;
int val = simple_strtoul(buf, NULL, 0);
+ if (!(clientdata->features & M41T80_FEATURE_SQ))
+ return -EINVAL;
+
if (val) {
if (!is_power_of_2(val))
return -EINVAL;
almon = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
if (almon < 0)
return -EIO;
- sqw = i2c_smbus_read_byte_data(client, M41T80_REG_SQW);
+ reg_sqw = M41T80_REG_SQW;
+ if (clientdata->features & M41T80_FEATURE_SQ_ALT)
+ reg_sqw = M41T80_REG_WDAY;
+ sqw = i2c_smbus_read_byte_data(client, reg_sqw);
if (sqw < 0)
return -EIO;
sqw = (sqw & 0x0f) | (val << 4);
if (i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
almon & ~M41T80_ALMON_SQWE) < 0 ||
- i2c_smbus_write_byte_data(client, M41T80_REG_SQW, sqw) < 0)
+ i2c_smbus_write_byte_data(client, reg_sqw, sqw) < 0)
return -EIO;
if (val && i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
almon | M41T80_ALMON_SQWE) < 0)
}
#endif
+#ifdef CONFIG_RTC_DRV_M41T80_WDT
+/*
+ *****************************************************************************
+ *
+ * Watchdog Driver
+ *
+ *****************************************************************************
+ */
+static struct i2c_client *save_client;
+
+/* Default margin */
+#define WD_TIMO 60 /* 1..31 seconds */
+
+static int wdt_margin = WD_TIMO;
+module_param(wdt_margin, int, 0);
+MODULE_PARM_DESC(wdt_margin, "Watchdog timeout in seconds (default 60s)");
+
+static unsigned long wdt_is_open;
+static int boot_flag;
+
+/**
+ * wdt_ping:
+ *
+ * Reload counter one with the watchdog timeout. We don't bother reloading
+ * the cascade counter.
+ */
+static void wdt_ping(void)
+{
+ unsigned char i2c_data[2];
+ struct i2c_msg msgs1[1] = {
+ {
+ .addr = save_client->addr,
+ .flags = 0,
+ .len = 2,
+ .buf = i2c_data,
+ },
+ };
+ struct m41t80_data *clientdata = i2c_get_clientdata(save_client);
+
+ i2c_data[0] = 0x09; /* watchdog register */
+
+ if (wdt_margin > 31)
+ i2c_data[1] = (wdt_margin & 0xFC) | 0x83; /* resolution = 4s */
+ else
+ /*
+ * WDS = 1 (0x80), mulitplier = WD_TIMO, resolution = 1s (0x02)
+ */
+ i2c_data[1] = wdt_margin<<2 | 0x82;
+
+ /*
+ * M41T65 has three bits for watchdog resolution. Don't set bit 7, as
+ * that would be an invalid resolution.
+ */
+ if (clientdata->features & M41T80_FEATURE_WD)
+ i2c_data[1] &= ~M41T80_WATCHDOG_RB2;
+
+ i2c_transfer(save_client->adapter, msgs1, 1);
+}
+
+/**
+ * wdt_disable:
+ *
+ * disables watchdog.
+ */
+static void wdt_disable(void)
+{
+ unsigned char i2c_data[2], i2c_buf[0x10];
+ struct i2c_msg msgs0[2] = {
+ {
+ .addr = save_client->addr,
+ .flags = 0,
+ .len = 1,
+ .buf = i2c_data,
+ },
+ {
+ .addr = save_client->addr,
+ .flags = I2C_M_RD,
+ .len = 1,
+ .buf = i2c_buf,
+ },
+ };
+ struct i2c_msg msgs1[1] = {
+ {
+ .addr = save_client->addr,
+ .flags = 0,
+ .len = 2,
+ .buf = i2c_data,
+ },
+ };
+
+ i2c_data[0] = 0x09;
+ i2c_transfer(save_client->adapter, msgs0, 2);
+
+ i2c_data[0] = 0x09;
+ i2c_data[1] = 0x00;
+ i2c_transfer(save_client->adapter, msgs1, 1);
+}
+
+/**
+ * wdt_write:
+ * @file: file handle to the watchdog
+ * @buf: buffer to write (unused as data does not matter here
+ * @count: count of bytes
+ * @ppos: pointer to the position to write. No seeks allowed
+ *
+ * A write to a watchdog device is defined as a keepalive signal. Any
+ * write of data will do, as we we don't define content meaning.
+ */
+static ssize_t wdt_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ /* Can't seek (pwrite) on this device
+ if (ppos != &file->f_pos)
+ return -ESPIPE;
+ */
+ if (count) {
+ wdt_ping();
+ return 1;
+ }
+ return 0;
+}
+
+static ssize_t wdt_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return 0;
+}
+
+/**
+ * wdt_ioctl:
+ * @inode: inode of the device
+ * @file: file handle to the device
+ * @cmd: watchdog command
+ * @arg: argument pointer
+ *
+ * The watchdog API defines a common set of functions for all watchdogs
+ * according to their available features. We only actually usefully support
+ * querying capabilities and current status.
+ */
+static int wdt_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int new_margin, rv;
+ static struct watchdog_info ident = {
+ .options = WDIOF_POWERUNDER | WDIOF_KEEPALIVEPING |
+ WDIOF_SETTIMEOUT,
+ .firmware_version = 1,
+ .identity = "M41T80 WTD"
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user((struct watchdog_info __user *)arg, &ident,
+ sizeof(ident)) ? -EFAULT : 0;
+
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(boot_flag, (int __user *)arg);
+ case WDIOC_KEEPALIVE:
+ wdt_ping();
+ return 0;
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_margin, (int __user *)arg))
+ return -EFAULT;
+ /* Arbitrary, can't find the card's limits */
+ if (new_margin < 1 || new_margin > 124)
+ return -EINVAL;
+ wdt_margin = new_margin;
+ wdt_ping();
+ /* Fall */
+ case WDIOC_GETTIMEOUT:
+ return put_user(wdt_margin, (int __user *)arg);
+
+ case WDIOC_SETOPTIONS:
+ if (copy_from_user(&rv, (int __user *)arg, sizeof(int)))
+ return -EFAULT;
+
+ if (rv & WDIOS_DISABLECARD) {
+ pr_info("rtc-m41t80: disable watchdog\n");
+ wdt_disable();
+ }
+
+ if (rv & WDIOS_ENABLECARD) {
+ pr_info("rtc-m41t80: enable watchdog\n");
+ wdt_ping();
+ }
+
+ return -EINVAL;
+ }
+ return -ENOTTY;
+}
+
+static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret;
+
+ lock_kernel();
+ ret = wdt_ioctl(file, cmd, arg);
+ unlock_kernel();
+
+ return ret;
+}
+
+/**
+ * wdt_open:
+ * @inode: inode of device
+ * @file: file handle to device
+ *
+ */
+static int wdt_open(struct inode *inode, struct file *file)
+{
+ if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
+ lock_kernel();
+ if (test_and_set_bit(0, &wdt_is_open)) {
+ unlock_kernel();
+ return -EBUSY;
+ }
+ /*
+ * Activate
+ */
+ wdt_is_open = 1;
+ unlock_kernel();
+ return 0;
+ }
+ return -ENODEV;
+}
+
+/**
+ * wdt_close:
+ * @inode: inode to board
+ * @file: file handle to board
+ *
+ */
+static int wdt_release(struct inode *inode, struct file *file)
+{
+ if (MINOR(inode->i_rdev) == WATCHDOG_MINOR)
+ clear_bit(0, &wdt_is_open);
+ return 0;
+}
+
+/**
+ * notify_sys:
+ * @this: our notifier block
+ * @code: the event being reported
+ * @unused: unused
+ *
+ * Our notifier is called on system shutdowns. We want to turn the card
+ * off at reboot otherwise the machine will reboot again during memory
+ * test or worse yet during the following fsck. This would suck, in fact
+ * trust me - if it happens it does suck.
+ */
+static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ if (code == SYS_DOWN || code == SYS_HALT)
+ /* Disable Watchdog */
+ wdt_disable();
+ return NOTIFY_DONE;
+}
+
+static const struct file_operations wdt_fops = {
+ .owner = THIS_MODULE,
+ .read = wdt_read,
+ .unlocked_ioctl = wdt_unlocked_ioctl,
+ .write = wdt_write,
+ .open = wdt_open,
+ .release = wdt_release,
+};
+
+static struct miscdevice wdt_dev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &wdt_fops,
+};
+
+/*
+ * The WDT card needs to learn about soft shutdowns in order to
+ * turn the timebomb registers off.
+ */
+static struct notifier_block wdt_notifier = {
+ .notifier_call = wdt_notify_sys,
+};
+#endif /* CONFIG_RTC_DRV_M41T80_WDT */
+
/*
*****************************************************************************
*
*
*****************************************************************************
*/
-static int m41t80_probe(struct i2c_client *client)
+static int m41t80_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
{
- int i, rc = 0;
+ int rc = 0;
struct rtc_device *rtc = NULL;
struct rtc_time tm;
- const struct m41t80_chip_info *chip;
struct m41t80_data *clientdata = NULL;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C
dev_info(&client->dev,
"chip found, driver version " DRV_VERSION "\n");
- chip = NULL;
- for (i = 0; i < ARRAY_SIZE(m41t80_chip_info_tbl); i++) {
- if (!strcmp(m41t80_chip_info_tbl[i].name, client->name)) {
- chip = &m41t80_chip_info_tbl[i];
- break;
- }
- }
- if (!chip) {
- dev_err(&client->dev, "%s is not supported\n", client->name);
- rc = -ENODEV;
- goto exit;
- }
-
clientdata = kzalloc(sizeof(*clientdata), GFP_KERNEL);
if (!clientdata) {
rc = -ENOMEM;
}
clientdata->rtc = rtc;
- clientdata->chip = chip;
+ clientdata->features = id->driver_data;
i2c_set_clientdata(client, clientdata);
/* Make sure HT (Halt Update) bit is cleared */
goto ht_err;
if (rc & M41T80_ALHOUR_HT) {
- if (chip->features & M41T80_FEATURE_HT) {
+ if (clientdata->features & M41T80_FEATURE_HT) {
m41t80_get_datetime(client, &tm);
dev_info(&client->dev, "HT bit was set!\n");
dev_info(&client->dev,
if (rc)
goto exit;
+#ifdef CONFIG_RTC_DRV_M41T80_WDT
+ if (clientdata->features & M41T80_FEATURE_HT) {
+ save_client = client;
+ rc = misc_register(&wdt_dev);
+ if (rc)
+ goto exit;
+ rc = register_reboot_notifier(&wdt_notifier);
+ if (rc) {
+ misc_deregister(&wdt_dev);
+ goto exit;
+ }
+ }
+#endif
return 0;
st_err:
struct m41t80_data *clientdata = i2c_get_clientdata(client);
struct rtc_device *rtc = clientdata->rtc;
+#ifdef CONFIG_RTC_DRV_M41T80_WDT
+ if (clientdata->features & M41T80_FEATURE_HT) {
+ misc_deregister(&wdt_dev);
+ unregister_reboot_notifier(&wdt_notifier);
+ }
+#endif
if (rtc)
rtc_device_unregister(rtc);
kfree(clientdata);
static struct i2c_driver m41t80_driver = {
.driver = {
- .name = "m41t80",
+ .name = "rtc-m41t80",
},
.probe = m41t80_probe,
.remove = m41t80_remove,
+ .id_table = m41t80_id,
};
static int __init m41t80_rtc_init(void)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff