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path: root/drivers/hwmon/lm78.c
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Diffstat (limited to 'drivers/hwmon/lm78.c')
-rw-r--r--drivers/hwmon/lm78.c270
1 files changed, 158 insertions, 112 deletions
diff --git a/drivers/hwmon/lm78.c b/drivers/hwmon/lm78.c
index ed7859f..b5e3b28 100644
--- a/drivers/hwmon/lm78.c
+++ b/drivers/hwmon/lm78.c
@@ -114,25 +114,16 @@ static inline int TEMP_FROM_REG(s8 val)
#define DIV_FROM_REG(val) (1 << (val))
-/* There are some complications in a module like this. First off, LM78 chips
- may be both present on the SMBus and the ISA bus, and we have to handle
- those cases separately at some places. Second, there might be several
- LM78 chips available (well, actually, that is probably never done; but
- it is a clean illustration of how to handle a case like that). Finally,
- a specific chip may be attached to *both* ISA and SMBus, and we would
- not like to detect it double. Fortunately, in the case of the LM78 at
- least, a register tells us what SMBus address we are on, so that helps
- a bit - except if there could be more than one SMBus. Groan. No solution
- for this yet. */
-
-/* For ISA chips, we abuse the i2c_client addr and name fields. We also use
- the driver field to differentiate between I2C and ISA chips. */
struct lm78_data {
- struct i2c_client client;
+ struct i2c_client *client;
struct device *hwmon_dev;
struct mutex lock;
enum chips type;
+ /* For ISA device only */
+ const char *name;
+ int isa_addr;
+
struct mutex update_lock;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */
@@ -151,9 +142,11 @@ struct lm78_data {
};
-static int lm78_attach_adapter(struct i2c_adapter *adapter);
-static int lm78_detect(struct i2c_adapter *adapter, int address, int kind);
-static int lm78_detach_client(struct i2c_client *client);
+static int lm78_i2c_detect(struct i2c_client *client, int kind,
+ struct i2c_board_info *info);
+static int lm78_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id);
+static int lm78_i2c_remove(struct i2c_client *client);
static int __devinit lm78_isa_probe(struct platform_device *pdev);
static int __devexit lm78_isa_remove(struct platform_device *pdev);
@@ -164,12 +157,23 @@ static struct lm78_data *lm78_update_device(struct device *dev);
static void lm78_init_device(struct lm78_data *data);
+static const struct i2c_device_id lm78_i2c_id[] = {
+ { "lm78", lm78 },
+ { "lm79", lm79 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lm78_i2c_id);
+
static struct i2c_driver lm78_driver = {
+ .class = I2C_CLASS_HWMON,
.driver = {
.name = "lm78",
},
- .attach_adapter = lm78_attach_adapter,
- .detach_client = lm78_detach_client,
+ .probe = lm78_i2c_probe,
+ .remove = lm78_i2c_remove,
+ .id_table = lm78_i2c_id,
+ .detect = lm78_i2c_detect,
+ .address_data = &addr_data,
};
static struct platform_driver lm78_isa_driver = {
@@ -454,17 +458,6 @@ static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_alarm, NULL, 11);
static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
-/* This function is called when:
- * lm78_driver is inserted (when this module is loaded), for each
- available adapter
- * when a new adapter is inserted (and lm78_driver is still present) */
-static int lm78_attach_adapter(struct i2c_adapter *adapter)
-{
- if (!(adapter->class & I2C_CLASS_HWMON))
- return 0;
- return i2c_probe(adapter, &addr_data, lm78_detect);
-}
-
static struct attribute *lm78_attributes[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
&sensor_dev_attr_in0_min.dev_attr.attr,
@@ -527,54 +520,77 @@ static ssize_t show_name(struct device *dev, struct device_attribute
{
struct lm78_data *data = dev_get_drvdata(dev);
- return sprintf(buf, "%s\n", data->client.name);
+ return sprintf(buf, "%s\n", data->name);
}
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
-/* This function is called by i2c_probe */
-static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
+/* Returns 1 if the I2C chip appears to be an alias of the ISA chip */
+static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
{
- int i, err;
- struct i2c_client *new_client;
- struct lm78_data *data;
- const char *client_name = "";
+ struct lm78_data *isa;
+ int i;
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
- err = -ENODEV;
- goto ERROR1;
+ if (!pdev) /* No ISA chip */
+ return 0;
+ isa = platform_get_drvdata(pdev);
+
+ if (lm78_read_value(isa, LM78_REG_I2C_ADDR) != client->addr)
+ return 0; /* Address doesn't match */
+ if ((lm78_read_value(isa, LM78_REG_CHIPID) & 0xfe) != (chipid & 0xfe))
+ return 0; /* Chip type doesn't match */
+
+ /* We compare all the limit registers, the config register and the
+ * interrupt mask registers */
+ for (i = 0x2b; i <= 0x3d; i++) {
+ if (lm78_read_value(isa, i) !=
+ i2c_smbus_read_byte_data(client, i))
+ return 0;
}
+ if (lm78_read_value(isa, LM78_REG_CONFIG) !=
+ i2c_smbus_read_byte_data(client, LM78_REG_CONFIG))
+ return 0;
+ for (i = 0x43; i <= 0x46; i++) {
+ if (lm78_read_value(isa, i) !=
+ i2c_smbus_read_byte_data(client, i))
+ return 0;
+ }
+
+ return 1;
+}
- /* OK. For now, we presume we have a valid client. We now create the
- client structure, even though we cannot fill it completely yet.
- But it allows us to access lm78_{read,write}_value. */
+static int lm78_i2c_detect(struct i2c_client *client, int kind,
+ struct i2c_board_info *info)
+{
+ int i;
+ struct lm78_data *isa = pdev ? platform_get_drvdata(pdev) : NULL;
+ const char *client_name;
+ struct i2c_adapter *adapter = client->adapter;
+ int address = client->addr;
- if (!(data = kzalloc(sizeof(struct lm78_data), GFP_KERNEL))) {
- err = -ENOMEM;
- goto ERROR1;
- }
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
- new_client = &data->client;
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &lm78_driver;
+ /* We block updates of the ISA device to minimize the risk of
+ concurrent access to the same LM78 chip through different
+ interfaces. */
+ if (isa)
+ mutex_lock(&isa->update_lock);
- /* Now, we do the remaining detection. */
if (kind < 0) {
- if (lm78_read_value(data, LM78_REG_CONFIG) & 0x80) {
- err = -ENODEV;
- goto ERROR2;
- }
- if (lm78_read_value(data, LM78_REG_I2C_ADDR) !=
- address) {
- err = -ENODEV;
- goto ERROR2;
- }
+ if ((i2c_smbus_read_byte_data(client, LM78_REG_CONFIG) & 0x80)
+ || i2c_smbus_read_byte_data(client, LM78_REG_I2C_ADDR)
+ != address)
+ goto err_nodev;
+
+ /* Explicitly prevent the misdetection of Winbond chips */
+ i = i2c_smbus_read_byte_data(client, 0x4f);
+ if (i == 0xa3 || i == 0x5c)
+ goto err_nodev;
}
/* Determine the chip type. */
if (kind <= 0) {
- i = lm78_read_value(data, LM78_REG_CHIPID);
+ i = i2c_smbus_read_byte_data(client, LM78_REG_CHIPID);
if (i == 0x00 || i == 0x20 /* LM78 */
|| i == 0x40) /* LM78-J */
kind = lm78;
@@ -586,33 +602,59 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
"parameter for unknown chip at "
"adapter %d, address 0x%02x\n",
i2c_adapter_id(adapter), address);
- err = -ENODEV;
- goto ERROR2;
+ goto err_nodev;
+ }
+
+ if (lm78_alias_detect(client, i)) {
+ dev_dbg(&adapter->dev, "Device at 0x%02x appears to "
+ "be the same as ISA device\n", address);
+ goto err_nodev;
}
}
- if (kind == lm78) {
- client_name = "lm78";
- } else if (kind == lm79) {
+ if (isa)
+ mutex_unlock(&isa->update_lock);
+
+ switch (kind) {
+ case lm79:
client_name = "lm79";
+ break;
+ default:
+ client_name = "lm78";
}
+ strlcpy(info->type, client_name, I2C_NAME_SIZE);
+
+ return 0;
+
+ err_nodev:
+ if (isa)
+ mutex_unlock(&isa->update_lock);
+ return -ENODEV;
+}
+
+static int lm78_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct lm78_data *data;
+ int err;
- /* Fill in the remaining client fields and put into the global list */
- strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
- data->type = kind;
+ data = kzalloc(sizeof(struct lm78_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
- /* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
- goto ERROR2;
+ i2c_set_clientdata(client, data);
+ data->client = client;
+ data->type = id->driver_data;
/* Initialize the LM78 chip */
lm78_init_device(data);
/* Register sysfs hooks */
- if ((err = sysfs_create_group(&new_client->dev.kobj, &lm78_group)))
+ err = sysfs_create_group(&client->dev.kobj, &lm78_group);
+ if (err)
goto ERROR3;
- data->hwmon_dev = hwmon_device_register(&new_client->dev);
+ data->hwmon_dev = hwmon_device_register(&client->dev);
if (IS_ERR(data->hwmon_dev)) {
err = PTR_ERR(data->hwmon_dev);
goto ERROR4;
@@ -621,26 +663,18 @@ static int lm78_detect(struct i2c_adapter *adapter, int address, int kind)
return 0;
ERROR4:
- sysfs_remove_group(&new_client->dev.kobj, &lm78_group);
+ sysfs_remove_group(&client->dev.kobj, &lm78_group);
ERROR3:
- i2c_detach_client(new_client);
-ERROR2:
kfree(data);
-ERROR1:
return err;
}
-static int lm78_detach_client(struct i2c_client *client)
+static int lm78_i2c_remove(struct i2c_client *client)
{
struct lm78_data *data = i2c_get_clientdata(client);
- int err;
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &lm78_group);
-
- if ((err = i2c_detach_client(client)))
- return err;
-
kfree(data);
return 0;
@@ -651,11 +685,10 @@ static int __devinit lm78_isa_probe(struct platform_device *pdev)
int err;
struct lm78_data *data;
struct resource *res;
- const char *name;
/* Reserve the ISA region */
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
- if (!request_region(res->start, LM78_EXTENT, "lm78")) {
+ if (!request_region(res->start + LM78_ADDR_REG_OFFSET, 2, "lm78")) {
err = -EBUSY;
goto exit;
}
@@ -665,18 +698,16 @@ static int __devinit lm78_isa_probe(struct platform_device *pdev)
goto exit_release_region;
}
mutex_init(&data->lock);
- data->client.addr = res->start;
- i2c_set_clientdata(&data->client, data);
+ data->isa_addr = res->start;
platform_set_drvdata(pdev, data);
if (lm78_read_value(data, LM78_REG_CHIPID) & 0x80) {
data->type = lm79;
- name = "lm79";
+ data->name = "lm79";
} else {
data->type = lm78;
- name = "lm78";
+ data->name = "lm78";
}
- strlcpy(data->client.name, name, I2C_NAME_SIZE);
/* Initialize the LM78 chip */
lm78_init_device(data);
@@ -699,7 +730,7 @@ static int __devinit lm78_isa_probe(struct platform_device *pdev)
device_remove_file(&pdev->dev, &dev_attr_name);
kfree(data);
exit_release_region:
- release_region(res->start, LM78_EXTENT);
+ release_region(res->start + LM78_ADDR_REG_OFFSET, 2);
exit:
return err;
}
@@ -707,13 +738,16 @@ static int __devinit lm78_isa_probe(struct platform_device *pdev)
static int __devexit lm78_isa_remove(struct platform_device *pdev)
{
struct lm78_data *data = platform_get_drvdata(pdev);
+ struct resource *res;
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&pdev->dev.kobj, &lm78_group);
device_remove_file(&pdev->dev, &dev_attr_name);
- release_region(data->client.addr, LM78_EXTENT);
kfree(data);
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ release_region(res->start + LM78_ADDR_REG_OFFSET, 2);
+
return 0;
}
@@ -724,13 +758,13 @@ static int __devexit lm78_isa_remove(struct platform_device *pdev)
would slow down the LM78 access and should not be necessary. */
static int lm78_read_value(struct lm78_data *data, u8 reg)
{
- struct i2c_client *client = &data->client;
+ struct i2c_client *client = data->client;
- if (!client->driver) { /* ISA device */
+ if (!client) { /* ISA device */
int res;
mutex_lock(&data->lock);
- outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
- res = inb_p(client->addr + LM78_DATA_REG_OFFSET);
+ outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
+ res = inb_p(data->isa_addr + LM78_DATA_REG_OFFSET);
mutex_unlock(&data->lock);
return res;
} else
@@ -746,12 +780,12 @@ static int lm78_read_value(struct lm78_data *data, u8 reg)
nowhere else be necessary! */
static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value)
{
- struct i2c_client *client = &data->client;
+ struct i2c_client *client = data->client;
- if (!client->driver) { /* ISA device */
+ if (!client) { /* ISA device */
mutex_lock(&data->lock);
- outb_p(reg, client->addr + LM78_ADDR_REG_OFFSET);
- outb_p(value, client->addr + LM78_DATA_REG_OFFSET);
+ outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
+ outb_p(value, data->isa_addr + LM78_DATA_REG_OFFSET);
mutex_unlock(&data->lock);
return 0;
} else
@@ -837,8 +871,17 @@ static int __init lm78_isa_found(unsigned short address)
{
int val, save, found = 0;
- if (!request_region(address, LM78_EXTENT, "lm78"))
+ /* We have to request the region in two parts because some
+ boards declare base+4 to base+7 as a PNP device */
+ if (!request_region(address, 4, "lm78")) {
+ pr_debug("lm78: Failed to request low part of region\n");
return 0;
+ }
+ if (!request_region(address + 4, 4, "lm78")) {
+ pr_debug("lm78: Failed to request high part of region\n");
+ release_region(address, 4);
+ return 0;
+ }
#define REALLY_SLOW_IO
/* We need the timeouts for at least some LM78-like
@@ -901,7 +944,8 @@ static int __init lm78_isa_found(unsigned short address)
val & 0x80 ? "LM79" : "LM78", (int)address);
release:
- release_region(address, LM78_EXTENT);
+ release_region(address + 4, 4);
+ release_region(address, 4);
return found;
}
@@ -949,14 +993,12 @@ static int __init sm_lm78_init(void)
{
int res;
- res = i2c_add_driver(&lm78_driver);
- if (res)
- goto exit;
-
+ /* We register the ISA device first, so that we can skip the
+ * registration of an I2C interface to the same device. */
if (lm78_isa_found(isa_address)) {
res = platform_driver_register(&lm78_isa_driver);
if (res)
- goto exit_unreg_i2c_driver;
+ goto exit;
/* Sets global pdev as a side effect */
res = lm78_isa_device_add(isa_address);
@@ -964,12 +1006,16 @@ static int __init sm_lm78_init(void)
goto exit_unreg_isa_driver;
}
+ res = i2c_add_driver(&lm78_driver);
+ if (res)
+ goto exit_unreg_isa_device;
+
return 0;
+ exit_unreg_isa_device:
+ platform_device_unregister(pdev);
exit_unreg_isa_driver:
platform_driver_unregister(&lm78_isa_driver);
- exit_unreg_i2c_driver:
- i2c_del_driver(&lm78_driver);
exit:
return res;
}