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From: Hans de Goede on 24 Mar 2010 04:40
Hi,

Nack:
As the watchdog has its own SIO logical device number, it should
have a separate driver, not have support glued to the hwmon driver.

Regards,

Hans


On 03/24/2010 12:12 AM, Giel van Schijndel wrote:
> Implement the watchdog API for the Fintek F71808E.
>
> Signed-off-by: Giel van Schijndel<me(a)mortis.eu>
> ---
> drivers/hwmon/f71882fg.c | 553 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 553 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/hwmon/f71882fg.c b/drivers/hwmon/f71882fg.c
> index 8006271..3604613 100644
> --- a/drivers/hwmon/f71882fg.c
> +++ b/drivers/hwmon/f71882fg.c
> @@ -26,14 +26,19 @@
> #include<linux/hwmon.h>
> #include<linux/hwmon-sysfs.h>
> #include<linux/err.h>
> +#include<linux/miscdevice.h>
> #include<linux/mutex.h>
> +#include<linux/notifier.h>
> #include<linux/io.h>
> #include<linux/acpi.h>
> +#include<linux/reboot.h>
> +#include<linux/watchdog.h>
>
> #define DRVNAME "f71882fg"
>
> #define SIO_F71858FG_LD_HWM 0x02 /* Hardware monitor logical device */
> #define SIO_F71882FG_LD_HWM 0x04 /* Hardware monitor logical device */
> +#define SIO_F71808FG_LD_WDT 0x07 /* Watchdog timer logical device */
> #define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */
> #define SIO_LOCK_KEY 0xAA /* Key to diasble Super-I/O */
>
> @@ -91,12 +96,52 @@
>
> #define F71882FG_REG_START 0x01
>
> +#define F71808FG_REG_WDO_CONF 0xf0
> +#define F71808FG_REG_WDT_CONF 0xf5
> +#define F71808FG_REG_WD_TIME 0xf6
> +
> +#define F71808FG_FLAG_WDOUT_EN 7
> +
> +#define F71808FG_FLAG_WDTMOUT_STS 5
> +#define F71808FG_FLAG_WD_EN 5
> +#define F71808FG_FLAG_WD_PULSE 4
> +#define F71808FG_FLAG_WD_UNIT 3
> +
> #define FAN_MIN_DETECT 366 /* Lowest detectable fanspeed */
>
> +/* Default values */
> +#define WATCHDOG_TIMEOUT 60 /* 1 minute default timeout */
> +#define WATCHDOG_MAX_TIMEOUT (60 * 255)
> +#define WATCHDOG_PULSE_WIDTH 125 /* 125 ms, default pulse width for
> + watchdog signal */
> +
> static unsigned short force_id;
> module_param(force_id, ushort, 0);
> MODULE_PARM_DESC(force_id, "Override the detected device ID");
>
> +static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
> +static int timeout = 60; /* default timeout in seconds */
> +module_param(timeout, int, 0);
> +MODULE_PARM_DESC(timeout,
> + "Watchdog timeout in seconds. 1<= timeout<="
> + __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
> + __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
> +
> +static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
> +module_param(pulse_width, uint, 0);
> +MODULE_PARM_DESC(pulse_width,
> + "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms"
> + " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
> +
> +static int nowayout = WATCHDOG_NOWAYOUT;
> +module_param(nowayout, bool, 0444);
> +MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
> +
> +static int start_withtimeout = 0;
> +module_param(start_withtimeout, uint, 0);
> +MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
> + " given initial timeout. Zero (default) disables this feature.");
> +
> enum chips { f71808fg, f71858fg, f71862fg, f71882fg, f71889fg, f8000 };
>
> static const char *f71882fg_names[] = {
> @@ -113,6 +158,9 @@ static struct platform_device *f71882fg_pdev;
> /* Super-I/O Function prototypes */
> static inline int superio_inb(int base, int reg);
> static inline int superio_inw(int base, int reg);
> +static inline void superio_outb(int base, int reg, u8 val);
> +static inline void superio_set_bit(int base, int reg, int bit);
> +static inline void superio_clear_bit(int base, int reg, int bit);
> static inline void superio_enter(int base);
> static inline void superio_select(int base, int ld);
> static inline void superio_exit(int base);
> @@ -162,6 +210,24 @@ struct f71882fg_data {
> s8 pwm_auto_point_temp[4][4];
> };
>
> +struct watchdog_data {
> + unsigned short sioaddr;
> + enum chips type;
> + unsigned long opened;
> + struct mutex lock;
> + char expect_close;
> + struct watchdog_info ident;
> +
> + unsigned short timeout;
> + u8 timer_val; /* content for the wd_time register */
> + char minutes_mode;
> + u8 pulse_val; /* pulse width flag */
> + char pulse_mode; /* enable pulse output mode? */
> + char caused_reboot; /* last reboot was by the watchdog */
> +};
> +
> +static struct watchdog_data *watchdog;
> +
> /* Sysfs in */
> static ssize_t show_in(struct device *dev, struct device_attribute *devattr,
> char *buf);
> @@ -883,6 +949,26 @@ static int superio_inw(int base, int reg)
> return val;
> }
>
> +static inline void superio_outb(int base, int reg, u8 val)
> +{
> + outb(reg, base);
> + outb(val, base + 1);
> +}
> +
> +static inline void superio_set_bit(int base, int reg, int bit)
> +{
> + unsigned long val = superio_inb(base, reg);
> + __set_bit(bit,&val);
> + superio_outb(base, reg, val);
> +}
> +
> +static inline void superio_clear_bit(int base, int reg, int bit)
> +{
> + unsigned long val = superio_inb(base, reg);
> + __clear_bit(bit,&val);
> + superio_outb(base, reg, val);
> +}
> +
> static inline void superio_enter(int base)
> {
> /* according to the datasheet the key must be send twice! */
> @@ -1941,6 +2027,430 @@ static void f71882fg_remove_sysfs_files(struct platform_device *pdev,
> device_remove_file(&pdev->dev,&attr[i].dev_attr);
> }
>
> +static int watchdog_set_timeout(int timeout)
> +{
> + if (!watchdog)
> + return -ENODEV;
> +
> + if (timeout<= 0
> + || timeout> max_timeout) {
> + printk(KERN_ERR DRVNAME ": watchdog timeout out of range\n");
> + return -EINVAL;
> + }
> +
> + mutex_lock(&watchdog->lock);
> +
> + watchdog->timeout = timeout;
> + if (timeout> 0xff) {
> + watchdog->timer_val = DIV_ROUND_UP(timeout, 60);
> + watchdog->minutes_mode = true;
> + } else {
> + watchdog->timer_val = timeout;
> + watchdog->minutes_mode = false;
> + }
> +
> + mutex_unlock(&watchdog->lock);
> +
> + return 0;
> +}
> +
> +static int watchdog_set_pulse_width(unsigned int pw)
> +{
> + int err = 0;
> +
> + if (!watchdog)
> + return -ENODEV;
> +
> + mutex_lock(&watchdog->lock);
> +
> + if (pw<= 1) {
> + watchdog->pulse_val = 0;
> + } else if (pw<= 25) {
> + watchdog->pulse_val = 1;
> + } else if (pw<= 125) {
> + watchdog->pulse_val = 2;
> + } else if (pw<= 5000) {
> + watchdog->pulse_val = 3;
> + } else {
> + printk(KERN_ERR DRVNAME ": watchdog pulse width out of range\n");
> + err = -EINVAL;
> + goto exit_unlock;
> + }
> +
> + watchdog->pulse_mode = pw;
> +
> +exit_unlock:
> + mutex_unlock(&watchdog->lock);
> + return err;
> +}
> +
> +static int watchdog_keepalive(void)
> +{
> + if (!watchdog)
> + return -ENODEV;
> +
> + mutex_lock(&watchdog->lock);
> + superio_enter(watchdog->sioaddr);
> +
> + if (watchdog->minutes_mode)
> + /* select minutes for timer units */
> + superio_set_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_UNIT);
> + else
> + /* select seconds for timer units */
> + superio_clear_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_UNIT);
> +
> + /* Set timer value */
> + superio_outb(watchdog->sioaddr, F71808FG_REG_WD_TIME,
> + watchdog->timeout);
> +
> + superio_exit(watchdog->sioaddr);
> + mutex_unlock(&watchdog->lock);
> + return 0;
> +}
> +
> +static int watchdog_start(void)
> +{
> + /* Make sure we don't die as soon as the watchdog is enabled below */
> + int err = watchdog_keepalive();
> + if (err)
> + return err;
> +
> + mutex_lock(&watchdog->lock);
> + superio_enter(watchdog->sioaddr);
> +
> + /* Watchdog pin configuration */
> + switch (watchdog->type) {
> + case f71808fg:
> + /* Set ping 21 to GPIO23/WDTRST#, then to WDTRST# */
> + superio_clear_bit(watchdog->sioaddr, 0x2a, 3);
> + superio_clear_bit(watchdog->sioaddr, 0x2b, 3);
> + break;
> +
> + default:
> + /* 'default' label to shut up the compiler and catch programmer errors */
> + err = -ENODEV;
> + goto exit_unlock;
> + }
> +
> + superio_select(watchdog->sioaddr, SIO_F71808FG_LD_WDT);
> + superio_set_bit(watchdog->sioaddr, SIO_REG_ENABLE, 0);
> + superio_set_bit(watchdog->sioaddr, F71808FG_REG_WDO_CONF,
> + F71808FG_FLAG_WDOUT_EN);
> +
> + superio_set_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_EN);
> +
> + if (watchdog->pulse_mode) {
> + /* Select "pulse" output mode with given duration */
> + u8 wdt_conf = superio_inb(watchdog->sioaddr,
> + F71808FG_REG_WDT_CONF);
> +
> + /* Set WD_PSWIDTH bits (1:0) */
> + wdt_conf = (wdt_conf& 0xfc) | (watchdog->pulse_val& 0x03);
> + /* Set WD_PULSE to "pulse" mode */
> + wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
> +
> + superio_outb(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + wdt_conf);
> + } else {
> + /* Select "level" output mode */
> + superio_clear_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_PULSE);
> + }
> +
> +exit_unlock:
> + superio_exit(watchdog->sioaddr);
> + mutex_unlock(&watchdog->lock);
> +
> + return err;
> +}
> +
> +static int watchdog_stop(void)
> +{
> + if (!watchdog)
> + return -ENODEV;
> +
> + mutex_lock(&watchdog->lock);
> + superio_enter(watchdog->sioaddr);
> +
> + superio_clear_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_EN);
> +
> + superio_exit(watchdog->sioaddr);
> + mutex_unlock(&watchdog->lock);
> +
> + return 0;
> +}
> +
> +static int watchdog_get_status(void)
> +{
> + int status = 0;
> +
> + if (!watchdog)
> + return -ENODEV;
> +
> + mutex_lock(&watchdog->lock);
> + status = (watchdog->caused_reboot) ? WDIOF_CARDRESET : 0;
> + mutex_unlock(&watchdog->lock);
> +
> + return status;
> +}
> +
> +/* /dev/watchdog api */
> +
> +static int watchdog_open(struct inode *inode, struct file *file)
> +{
> + int err;
> +
> + /* If the watchdog is alive we don't need to start it again */
> + if (test_and_set_bit(0,&watchdog->opened))
> + return -EBUSY;
> +
> + err = watchdog_start();
> + if (err) {
> + clear_bit(0,&watchdog->opened);
> + return err;
> + }
> +
> + if (nowayout)
> + __module_get(THIS_MODULE);
> +
> + watchdog->expect_close = 0;
> + return nonseekable_open(inode, file);
> +}
> +
> +static int watchdog_release(struct inode *inode, struct file *file)
> +{
> + clear_bit(0,&watchdog->opened);
> +
> + if (!watchdog->expect_close) {
> + watchdog_keepalive();
> + printk(KERN_CRIT DRVNAME
> + ": Unexpected close, not stopping watchdog!\n");
> + } else if (!nowayout) {
> + watchdog_stop();
> + }
> + return 0;
> +}
> +
> +/*
> + * watchdog_write:
> + * @file: file handle to the watchdog
> + * @buf: buffer to write
> + * @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 watchdog_write(struct file *file, const char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + if (count) {
> + if (!nowayout) {
> + size_t i;
> +
> + /* In case it was set long ago */
> + bool expect_close = false;
> +
> + for (i = 0; i != count; i++) {
> + char c;
> + if (get_user(c, buf + i))
> + return -EFAULT;
> + expect_close = (c == 'V');
> + }
> +
> + /* Lock to properly order writes across fork()ed processes */
> + mutex_lock(&watchdog->lock);
> + watchdog->expect_close = expect_close;
> + mutex_unlock(&watchdog->lock);
> + }
> +
> + /* someone wrote to us, we should restart timer */
> + watchdog_keepalive();
> + }
> + return count;
> +}
> +
> +/*
> + * watchdog_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.
> + */
> +static long watchdog_ioctl(struct file *file, unsigned int cmd,
> + unsigned long arg)
> +{
> + int status;
> + int new_options;
> + int new_timeout;
> + union {
> + struct watchdog_info __user *ident;
> + int __user *i;
> + } uarg;
> +
> + uarg.i = (int __user *)arg;
> +
> + switch (cmd) {
> + case WDIOC_GETSUPPORT:
> + return copy_to_user(uarg.ident,&watchdog->ident,
> + sizeof(watchdog->ident)) ? -EFAULT : 0;
> +
> + case WDIOC_GETSTATUS:
> + status = watchdog_get_status();
> + if (status< 0)
> + return status;
> + return put_user(status, uarg.i);
> +
> + case WDIOC_GETBOOTSTATUS:
> + return put_user(0, uarg.i);
> +
> + case WDIOC_SETOPTIONS:
> + if (get_user(new_options, uarg.i))
> + return -EFAULT;
> +
> + if (new_options& WDIOS_DISABLECARD) {
> + watchdog_stop();
> + }
> +
> + if (new_options& WDIOS_ENABLECARD)
> + return watchdog_start();
> +
> +
> + case WDIOC_KEEPALIVE:
> + watchdog_keepalive();
> + return 0;
> +
> + case WDIOC_SETTIMEOUT:
> + if (get_user(new_timeout, uarg.i))
> + return -EFAULT;
> +
> + if (watchdog_set_timeout(new_timeout))
> + return -EINVAL;
> +
> + watchdog_keepalive();
> + /* Fall */
> +
> + case WDIOC_GETTIMEOUT:
> + return put_user(watchdog->timeout, uarg.i);
> +
> + default:
> + return -ENOTTY;
> +
> + }
> +}
> +
> +static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
> + void *unused)
> +{
> + if (code == SYS_DOWN || code == SYS_HALT)
> + watchdog_stop();
> + return NOTIFY_DONE;
> +}
> +
> +static const struct file_operations watchdog_fops = {
> + .owner = THIS_MODULE,
> + .llseek = no_llseek,
> + .open = watchdog_open,
> + .release = watchdog_release,
> + .write = watchdog_write,
> + .unlocked_ioctl = watchdog_ioctl,
> +};
> +
> +static struct miscdevice watchdog_miscdev = {
> + .minor = WATCHDOG_MINOR,
> + .name = "watchdog",
> + .fops =&watchdog_fops,
> +};
> +
> +static struct notifier_block watchdog_notifier = {
> + .notifier_call = watchdog_notify_sys,
> +};
> +
> +static int __init watchdog_init(void)
> +{
> + int err = 0;
> +
> + if (!request_region(watchdog->sioaddr, 2,
> + watchdog->ident.identity)) {
> + printk(KERN_ERR DRVNAME
> + ": I/O address 0x%04x already in use\n",
> + (int)watchdog->sioaddr);
> + return -EIO;
> + }
> +
> + err = register_reboot_notifier(&watchdog_notifier);
> + if (err)
> + goto exit_region;
> +
> + err = misc_register(&watchdog_miscdev);
> + if (err) {
> + printk(KERN_ERR DRVNAME
> + ": cannot register miscdev on minor=%d\n",
> + watchdog_miscdev.minor);
> + goto exit_reboot;
> + }
> +
> + if (start_withtimeout) {
> + if (start_withtimeout<= 0
> + || start_withtimeout> max_timeout) {
> + printk(KERN_ERR DRVNAME ": watchdog starting timeout out of range\n");
> + err = -EINVAL;
> + goto exit_reboot;
> + }
> +
> + err = watchdog_start();
> + if (err) {
> + printk(KERN_ERR DRVNAME
> + ": cannot start watchdog timer\n");
> + goto exit_reboot;
> + }
> +
> + mutex_lock(&watchdog->lock);
> + superio_enter(watchdog->sioaddr);
> +
> + if (start_withtimeout> 0xff) {
> + /* select minutes for timer units */
> + superio_set_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_UNIT);
> + superio_outb(watchdog->sioaddr, F71808FG_REG_WD_TIME,
> + DIV_ROUND_UP(start_withtimeout, 60));
> + } else {
> + /* select seconds for timer units */
> + superio_clear_bit(watchdog->sioaddr, F71808FG_REG_WDT_CONF,
> + F71808FG_FLAG_WD_UNIT);
> + superio_outb(watchdog->sioaddr, F71808FG_REG_WD_TIME,
> + start_withtimeout);
> + }
> +
> + superio_exit(watchdog->sioaddr);
> + mutex_unlock(&watchdog->lock);
> +
> + if (nowayout)
> + __module_get(THIS_MODULE);
> +
> + printk(KERN_INFO DRVNAME
> + ": watchdog started with initial timeout of %d seconds!\n",
> + start_withtimeout);
> + }
> +
> + return 0;
> +
> +exit_reboot:
> + unregister_reboot_notifier(&watchdog_notifier);
> +exit_region:
> + release_region(watchdog->sioaddr, 2);
> +
> + return err;
> +}
> +
> static int __devinit f71882fg_probe(struct platform_device *pdev)
> {
> struct f71882fg_data *data;
> @@ -2236,8 +2746,32 @@ static int f71882fg_remove(struct platform_device *pdev)
> static int __init f71882fg_find_watchdog(int sioaddr,
> const struct f71882fg_sio_data *sio_data)
> {
> + int err = 0;
> +
> switch (sio_data->type) {
> case f71808fg:
> + watchdog = kzalloc(sizeof(*watchdog), GFP_KERNEL);
> + if (!watchdog)
> + return -ENOMEM;
> +
> + mutex_init(&watchdog->lock);
> + watchdog->sioaddr = sioaddr;
> + watchdog->type = sio_data->type;
> +
> + watchdog->ident.options = WDIOC_SETTIMEOUT
> + | WDIOF_MAGICCLOSE
> + | WDIOF_KEEPALIVEPING;
> + snprintf(watchdog->ident.identity,
> + sizeof(watchdog->ident.identity), "%s watchdog",
> + f71882fg_names[watchdog->type]);
> +
> + err = watchdog_set_timeout(timeout);
> + if (err)
> + goto exit_alloc;
> + err = watchdog_set_pulse_width(pulse_width);
> + if (err)
> + goto exit_alloc;
> +
> break;
>
> case f71862fg:
> @@ -2256,6 +2790,12 @@ static int __init f71882fg_find_watchdog(int sioaddr,
> }
>
> return 0;
> +
> +exit_alloc:
> + kfree(watchdog);
> + watchdog = NULL;
> +
> + return err;
> }
>
> static int __init f71882fg_find_hwmon(int sioaddr, unsigned short *hwmon_addr,
> @@ -2421,6 +2961,12 @@ static int __init f71882fg_init(void)
> if (err)
> goto exit_driver;
>
> + if (watchdog) {
> + err = watchdog_init();
> + if (err)
> + goto exit_driver;
> + }
> +
> return 0;
>
> exit_driver:
> @@ -2433,6 +2979,13 @@ static void __exit f71882fg_exit(void)
> {
> platform_device_unregister(f71882fg_pdev);
> platform_driver_unregister(&f71882fg_driver);
> +
> + if (watchdog) {
> + watchdog_stop();
> + misc_deregister(&watchdog_miscdev);
> + unregister_reboot_notifier(&watchdog_notifier);
> + release_region(watchdog->sioaddr, 2);
> + }
> }
>
> MODULE_DESCRIPTION("F71882FG Hardware Monitoring Driver");
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From: Hans de Goede on 24 Mar 2010 06:40
Hi,

On 03/24/2010 10:36 AM, Giel van Schijndel wrote:
> On Wed, Mar 24, 2010 at 09:37:43AM +0100, Hans de Goede wrote:
>> Nack:
>> As the watchdog has its own SIO logical device number, it should
>> have a separate driver, not have support glued to the hwmon driver.
>
> Thus, if I understand correctly, you would suggest for me to implement a
> new driver in drivers/watchdog/ to implement this driver?
>

Yes, correct.

Regards,

Hans
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From: Alan Cox on 24 Mar 2010 11:50
> hold on the SIO port range. This would thus interfere with the operation
> of the f71882fg driver. I.e. it would prevent the device probing stage
> from working, thus preventing it from loading *after* my in-development
> watchdog driver.

There are two ways to deal with that really

1. Add a multi-function driver - it finds the chip and claims the port
regions and then provides methods for locked access to them as well as
creating other device instances that the drivers map to (probably platform
devices ?) which in turn trigger the loading/binding of the relevant low
level devices.

2. Fix the kernel request_resource stuff to support a sleeping non
exclusive resource so request/free of regions can be used as a resource
semaphore by co-operative devices.

#2 is actually not hard but when I did the patch originally it then
wasn't needed by the driver I had in mind for other reasons.

See http://groups.google.com/group/linux.kernel/msg/1425fc2aad32e6ea

Maybe its worth resurrecting ?

Alan
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From: Hans de Goede on 24 Mar 2010 12:30
Hi,

On 03/24/2010 04:51 PM, Alan Cox wrote:
>> hold on the SIO port range. This would thus interfere with the operation
>> of the f71882fg driver. I.e. it would prevent the device probing stage
>> from working, thus preventing it from loading *after* my in-development
>> watchdog driver.
>
> There are two ways to deal with that really
>
> 1. Add a multi-function driver - it finds the chip and claims the port
> regions and then provides methods for locked access to them as well as
> creating other device instances that the drivers map to (probably platform
> devices ?) which in turn trigger the loading/binding of the relevant low
> level devices.
>
> 2. Fix the kernel request_resource stuff to support a sleeping non
> exclusive resource so request/free of regions can be used as a resource
> semaphore by co-operative devices.
>
> #2 is actually not hard but when I did the patch originally it then
> wasn't needed by the driver I had in mind for other reasons.
>
> See http://groups.google.com/group/linux.kernel/msg/1425fc2aad32e6ea
>
> Maybe its worth resurrecting ?
>

Or, a bit more specific solution would be to resurrect the superio lock
coordinator patches, which were written (but never merged) 2 years ago
to solve exactly this problem:
http://lists.lm-sensors.org/pipermail/lm-sensors/2008-July/023743.html

Regards,

Hans
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From: Alan Cox on 25 Mar 2010 08:50
O> Using Alan's patch and the one following the dashed line I can implement
> (and have already done so) a separate watchdog driver for the Fintek
> F71808E.
>
> Should I just ask for this patch to be applied together with Alan's?
> Then submit the new driver? (I'm a bit new to the non-technical aspects
> of Linux kernel development).

I'd expect to see a submission of three patches I think

1. Patch adding the muxed resource support
2. Patch making the hwmon driver use it
3. Patch adding the new driver which needs it

and then we have a few other bits of code that probably should adopt it,
but that is a separate matter and other maintainers can do that bit.

Alan
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