diff options
Diffstat (limited to 'drivers/hwmon/lm78.c')
-rw-r--r-- | drivers/hwmon/lm78.c | 270 |
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; } |