diff options
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/hwmon/fschmd.c | 401 |
2 files changed, 386 insertions, 20 deletions
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index aba01b4ceca4..91975148f4b9 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -329,10 +329,11 @@ config SENSORS_FSCHMD depends on X86 && I2C && EXPERIMENTAL help If you say yes here you get support for various Fujitsu Siemens - Computers sensor chips. + Computers sensor chips, including support for the integrated + watchdog. This is a new merged driver for FSC sensor chips which is intended - as a replacment for the fscpos, fscscy and fscher drivers and adds + as a replacement for the fscpos, fscscy and fscher drivers and adds support for several other FCS sensor chips. This driver can also be built as a module. If so, the module diff --git a/drivers/hwmon/fschmd.c b/drivers/hwmon/fschmd.c index c188b7135025..8bb1a44a1de5 100644 --- a/drivers/hwmon/fschmd.c +++ b/drivers/hwmon/fschmd.c @@ -42,11 +42,20 @@ #include <linux/mutex.h> #include <linux/sysfs.h> #include <linux/dmi.h> +#include <linux/fs.h> +#include <linux/watchdog.h> +#include <linux/miscdevice.h> +#include <linux/uaccess.h> +#include <linux/kref.h> /* Addresses to scan */ static const unsigned short normal_i2c[] = { 0x73, I2C_CLIENT_END }; /* Insmod parameters */ +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); I2C_CLIENT_INSMOD_5(fscpos, fscher, fscscy, fschrc, fschmd); /* @@ -65,11 +74,18 @@ I2C_CLIENT_INSMOD_5(fscpos, fscher, fscscy, fschrc, fschmd); #define FSCHMD_CONTROL_ALERT_LED 0x01 -/* watchdog (support to be implemented) */ +/* watchdog */ #define FSCHMD_REG_WDOG_PRESET 0x28 #define FSCHMD_REG_WDOG_STATE 0x23 #define FSCHMD_REG_WDOG_CONTROL 0x21 +#define FSCHMD_WDOG_CONTROL_TRIGGER 0x10 +#define FSCHMD_WDOG_CONTROL_STARTED 0x10 /* the same as trigger */ +#define FSCHMD_WDOG_CONTROL_STOP 0x20 +#define FSCHMD_WDOG_CONTROL_RESOLUTION 0x40 + +#define FSCHMD_WDOG_STATE_CARDRESET 0x02 + /* voltages, weird order is to keep the same order as the old drivers */ static const u8 FSCHMD_REG_VOLT[3] = { 0x45, 0x42, 0x48 }; @@ -206,14 +222,26 @@ static struct i2c_driver fschmd_driver = { */ struct fschmd_data { + struct i2c_client *client; struct device *hwmon_dev; struct mutex update_lock; + struct mutex watchdog_lock; + struct list_head list; /* member of the watchdog_data_list */ + struct kref kref; + struct miscdevice watchdog_miscdev; int kind; + unsigned long watchdog_is_open; + char watchdog_expect_close; + char watchdog_name[10]; /* must be unique to avoid sysfs conflict */ char valid; /* zero until following fields are valid */ unsigned long last_updated; /* in jiffies */ /* register values */ + u8 revision; /* chip revision */ u8 global_control; /* global control register */ + u8 watchdog_control; /* watchdog control register */ + u8 watchdog_state; /* watchdog status register */ + u8 watchdog_preset; /* watchdog counter preset on trigger val */ u8 volt[3]; /* 12, 5, battery voltage */ u8 temp_act[5]; /* temperature */ u8 temp_status[5]; /* status of sensor */ @@ -225,11 +253,28 @@ struct fschmd_data { }; /* Global variables to hold information read from special DMI tables, which are - available on FSC machines with an fscher or later chip. */ + available on FSC machines with an fscher or later chip. There is no need to + protect these with a lock as they are only modified from our attach function + which always gets called with the i2c-core lock held and never accessed + before the attach function is done with them. */ static int dmi_mult[3] = { 490, 200, 100 }; static int dmi_offset[3] = { 0, 0, 0 }; static int dmi_vref = -1; +/* Somewhat ugly :( global data pointer list with all fschmd devices, so that + we can find our device data as when using misc_register there is no other + method to get to ones device data from the open fop. */ +static LIST_HEAD(watchdog_data_list); +/* Note this lock not only protect list access, but also data.kref access */ +static DEFINE_MUTEX(watchdog_data_mutex); + +/* Release our data struct when we're detached from the i2c client *and* all + references to our watchdog device are released */ +static void fschmd_release_resources(struct kref *ref) +{ + struct fschmd_data *data = container_of(ref, struct fschmd_data, kref); + kfree(data); +} /* * Sysfs attr show / store functions @@ -548,7 +593,265 @@ static struct sensor_device_attribute fschmd_fan_attr[] = { /* - * Real code + * Watchdog routines + */ + +static int watchdog_set_timeout(struct fschmd_data *data, int timeout) +{ + int ret, resolution; + int kind = data->kind + 1; /* 0-x array index -> 1-x module param */ + + /* 2 second or 60 second resolution? */ + if (timeout <= 510 || kind == fscpos || kind == fscscy) + resolution = 2; + else + resolution = 60; + + if (timeout < resolution || timeout > (resolution * 255)) + return -EINVAL; + + mutex_lock(&data->watchdog_lock); + if (!data->client) { + ret = -ENODEV; + goto leave; + } + + if (resolution == 2) + data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_RESOLUTION; + else + data->watchdog_control |= FSCHMD_WDOG_CONTROL_RESOLUTION; + + data->watchdog_preset = DIV_ROUND_UP(timeout, resolution); + + /* Write new timeout value */ + i2c_smbus_write_byte_data(data->client, FSCHMD_REG_WDOG_PRESET, + data->watchdog_preset); + /* Write new control register, do not trigger! */ + i2c_smbus_write_byte_data(data->client, FSCHMD_REG_WDOG_CONTROL, + data->watchdog_control & ~FSCHMD_WDOG_CONTROL_TRIGGER); + + ret = data->watchdog_preset * resolution; + +leave: + mutex_unlock(&data->watchdog_lock); + return ret; +} + +static int watchdog_get_timeout(struct fschmd_data *data) +{ + int timeout; + + mutex_lock(&data->watchdog_lock); + if (data->watchdog_control & FSCHMD_WDOG_CONTROL_RESOLUTION) + timeout = data->watchdog_preset * 60; + else + timeout = data->watchdog_preset * 2; + mutex_unlock(&data->watchdog_lock); + + return timeout; +} + +static int watchdog_trigger(struct fschmd_data *data) +{ + int ret = 0; + + mutex_lock(&data->watchdog_lock); + if (!data->client) { + ret = -ENODEV; + goto leave; + } + + data->watchdog_control |= FSCHMD_WDOG_CONTROL_TRIGGER; + i2c_smbus_write_byte_data(data->client, FSCHMD_REG_WDOG_CONTROL, + data->watchdog_control); +leave: + mutex_unlock(&data->watchdog_lock); + return ret; +} + +static int watchdog_stop(struct fschmd_data *data) +{ + int ret = 0; + + mutex_lock(&data->watchdog_lock); + if (!data->client) { + ret = -ENODEV; + goto leave; + } + + data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_STARTED; + /* Don't store the stop flag in our watchdog control register copy, as + its a write only bit (read always returns 0) */ + i2c_smbus_write_byte_data(data->client, FSCHMD_REG_WDOG_CONTROL, + data->watchdog_control | FSCHMD_WDOG_CONTROL_STOP); +leave: + mutex_unlock(&data->watchdog_lock); + return ret; +} + +static int watchdog_open(struct inode *inode, struct file *filp) +{ + struct fschmd_data *pos, *data = NULL; + + /* We get called from drivers/char/misc.c with misc_mtx hold, and we + call misc_register() from fschmd_probe() with watchdog_data_mutex + hold, as misc_register() takes the misc_mtx lock, this is a possible + deadlock, so we use mutex_trylock here. */ + if (!mutex_trylock(&watchdog_data_mutex)) + return -ERESTARTSYS; + list_for_each_entry(pos, &watchdog_data_list, list) { + if (pos->watchdog_miscdev.minor == iminor(inode)) { + data = pos; + break; + } + } + /* Note we can never not have found data, so we don't check for this */ + kref_get(&data->kref); + mutex_unlock(&watchdog_data_mutex); + + if (test_and_set_bit(0, &data->watchdog_is_open)) + return -EBUSY; + + /* Start the watchdog */ + watchdog_trigger(data); + filp->private_data = data; + + return nonseekable_open(inode, filp); +} + +static int watchdog_release(struct inode *inode, struct file *filp) +{ + struct fschmd_data *data = filp->private_data; + + if (data->watchdog_expect_close) { + watchdog_stop(data); + data->watchdog_expect_close = 0; + } else { + watchdog_trigger(data); + dev_crit(&data->client->dev, + "unexpected close, not stopping watchdog!\n"); + } + + clear_bit(0, &data->watchdog_is_open); + + mutex_lock(&watchdog_data_mutex); + kref_put(&data->kref, fschmd_release_resources); + mutex_unlock(&watchdog_data_mutex); + + return 0; +} + +static ssize_t watchdog_write(struct file *filp, const char __user *buf, + size_t count, loff_t *offset) +{ + size_t ret; + struct fschmd_data *data = filp->private_data; + + if (count) { + if (!nowayout) { + size_t i; + + /* Clear it in case it was set with a previous write */ + data->watchdog_expect_close = 0; + + for (i = 0; i != count; i++) { + char c; + if (get_user(c, buf + i)) + return -EFAULT; + if (c == 'V') + data->watchdog_expect_close = 1; + } + } + ret = watchdog_trigger(data); + if (ret < 0) + return ret; + } + return count; +} + +static int watchdog_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg) +{ + static struct watchdog_info ident = { + .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | + WDIOF_CARDRESET, + .identity = "FSC watchdog" + }; + int i, ret = 0; + struct fschmd_data *data = filp->private_data; + + switch (cmd) { + case WDIOC_GETSUPPORT: + ident.firmware_version = data->revision; + if (!nowayout) + ident.options |= WDIOF_MAGICCLOSE; + if (copy_to_user((void __user *)arg, &ident, sizeof(ident))) + ret = -EFAULT; + break; + + case WDIOC_GETSTATUS: + ret = put_user(0, (int __user *)arg); + break; + + case WDIOC_GETBOOTSTATUS: + if (data->watchdog_state & FSCHMD_WDOG_STATE_CARDRESET) + ret = put_user(WDIOF_CARDRESET, (int __user *)arg); + else + ret = put_user(0, (int __user *)arg); + break; + + case WDIOC_KEEPALIVE: + ret = watchdog_trigger(data); + break; + + case WDIOC_GETTIMEOUT: + i = watchdog_get_timeout(data); + ret = put_user(i, (int __user *)arg); + break; + + case WDIOC_SETTIMEOUT: + if (get_user(i, (int __user *)arg)) { + ret = -EFAULT; + break; + } + ret = watchdog_set_timeout(data, i); + if (ret > 0) + ret = put_user(ret, (int __user *)arg); + break; + + case WDIOC_SETOPTIONS: + if (get_user(i, (int __user *)arg)) { + ret = -EFAULT; + break; + } + + if (i & WDIOS_DISABLECARD) + ret = watchdog_stop(data); + else if (i & WDIOS_ENABLECARD) + ret = watchdog_trigger(data); + else + ret = -EINVAL; + + break; + default: + ret = -ENOTTY; + } + + return ret; +} + +static struct file_operations watchdog_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .open = watchdog_open, + .release = watchdog_release, + .write = watchdog_write, + .ioctl = watchdog_ioctl, +}; + + +/* + * Detect, register, unregister and update device functions */ /* DMI decode routine to read voltage scaling factors from special DMI tables, @@ -658,9 +961,9 @@ static int fschmd_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct fschmd_data *data; - u8 revision; const char * const names[5] = { "Poseidon", "Hermes", "Scylla", "Heracles", "Heimdall" }; + const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 }; int i, err; enum chips kind = id->driver_data; @@ -670,6 +973,13 @@ static int fschmd_probe(struct i2c_client *client, i2c_set_clientdata(client, data); mutex_init(&data->update_lock); + mutex_init(&data->watchdog_lock); + INIT_LIST_HEAD(&data->list); + kref_init(&data->kref); + /* Store client pointer in our data struct for watchdog usage + (where the client is found through a data ptr instead of the + otherway around) */ + data->client = client; if (kind == fscpos) { /* The Poseidon has hardwired temp limits, fill these @@ -690,6 +1000,17 @@ static int fschmd_probe(struct i2c_client *client, } } + /* Read in some never changing registers */ + data->revision = i2c_smbus_read_byte_data(client, FSCHMD_REG_REVISION); + data->global_control = i2c_smbus_read_byte_data(client, + FSCHMD_REG_CONTROL); + data->watchdog_control = i2c_smbus_read_byte_data(client, + FSCHMD_REG_WDOG_CONTROL); + data->watchdog_state = i2c_smbus_read_byte_data(client, + FSCHMD_REG_WDOG_STATE); + data->watchdog_preset = i2c_smbus_read_byte_data(client, + FSCHMD_REG_WDOG_PRESET); + /* i2c kind goes from 1-5, we want from 0-4 to address arrays */ data->kind = kind - 1; @@ -732,9 +1053,43 @@ static int fschmd_probe(struct i2c_client *client, goto exit_detach; } - revision = i2c_smbus_read_byte_data(client, FSCHMD_REG_REVISION); + /* We take the data_mutex lock early so that watchdog_open() cannot + run when misc_register() has completed, but we've not yet added + our data to the watchdog_data_list (and set the default timeout) */ + mutex_lock(&watchdog_data_mutex); + for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) { + /* Register our watchdog part */ + snprintf(data->watchdog_name, sizeof(data->watchdog_name), + "watchdog%c", (i == 0) ? '\0' : ('0' + i)); + data->watchdog_miscdev.name = data->watchdog_name; + data->watchdog_miscdev.fops = &watchdog_fops; + data->watchdog_miscdev.minor = watchdog_minors[i]; + err = misc_register(&data->watchdog_miscdev); + if (err == -EBUSY) + continue; + if (err) { + data->watchdog_miscdev.minor = 0; + dev_err(&client->dev, + "Registering watchdog chardev: %d\n", err); + break; + } + + list_add(&data->list, &watchdog_data_list); + watchdog_set_timeout(data, 60); + dev_info(&client->dev, + "Registered watchdog chardev major 10, minor: %d\n", + watchdog_minors[i]); + break; + } + if (i == ARRAY_SIZE(watchdog_minors)) { + data->watchdog_miscdev.minor = 0; + dev_warn(&client->dev, "Couldn't register watchdog chardev " + "(due to no free minor)\n"); + } + mutex_unlock(&watchdog_data_mutex); + dev_info(&client->dev, "Detected FSC %s chip, revision: %d\n", - names[data->kind], (int) revision); + names[data->kind], (int) data->revision); return 0; @@ -748,6 +1103,24 @@ static int fschmd_remove(struct i2c_client *client) struct fschmd_data *data = i2c_get_clientdata(client); int i; + /* Unregister the watchdog (if registered) */ + if (data->watchdog_miscdev.minor) { + misc_deregister(&data->watchdog_miscdev); + if (data->watchdog_is_open) { + dev_warn(&client->dev, + "i2c client detached with watchdog open! " + "Stopping watchdog.\n"); + watchdog_stop(data); + } + mutex_lock(&watchdog_data_mutex); + list_del(&data->list); + mutex_unlock(&watchdog_data_mutex); + /* Tell the watchdog code the client is gone */ + mutex_lock(&data->watchdog_lock); + data->client = NULL; + mutex_unlock(&data->watchdog_lock); + } + /* Check if registered in case we're called from fschmd_detect to cleanup after an error */ if (data->hwmon_dev) @@ -762,7 +1135,10 @@ static int fschmd_remove(struct i2c_client *client) device_remove_file(&client->dev, &fschmd_fan_attr[i].dev_attr); - kfree(data); + mutex_lock(&watchdog_data_mutex); + kref_put(&data->kref, fschmd_release_resources); + mutex_unlock(&watchdog_data_mutex); + return 0; } @@ -824,17 +1200,6 @@ static struct fschmd_data *fschmd_update_device(struct device *dev) data->volt[i] = i2c_smbus_read_byte_data(client, FSCHMD_REG_VOLT[i]); - data->global_control = i2c_smbus_read_byte_data(client, - FSCHMD_REG_CONTROL); - - /* To be implemented in the future - data->watchdog[0] = i2c_smbus_read_byte_data(client, - FSCHMD_REG_WDOG_PRESET); - data->watchdog[1] = i2c_smbus_read_byte_data(client, - FSCHMD_REG_WDOG_STATE); - data->watchdog[2] = i2c_smbus_read_byte_data(client, - FSCHMD_REG_WDOG_CONTROL); */ - data->last_updated = jiffies; data->valid = 1; } |