On 10/12/11 10:36, michael.hennerich@xxxxxxxxxx wrote: > From: Michael Hennerich <michael.hennerich@xxxxxxxxxx> > > The Analog Devices ADT75 has an additional register at 0x04 > for initiating oneshot captures. It is not actively used in > this driver but we must avoid assuming it will behave as > 0x05-0x07 do and return the last read value. In fact register 0x04 > reads the same as register 0x00. And all registers are repetitive > mirrored around register 0x04. This fact is used to detect the ADT75. > > This patch is based on an reworked proposal from Jonathan Cameron <jic23@xxxxxxxxx> Definitely looks like it will fail on all the other parts supported, so should be fine. > > Signed-off-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx> Acked-by: Jonathan Cameron <jic23@xxxxxxxxx> > --- > Documentation/hwmon/lm75 | 5 +++++ > drivers/hwmon/Kconfig | 1 + > drivers/hwmon/lm75.c | 30 ++++++++++++++++++++++++++---- > 3 files changed, 32 insertions(+), 4 deletions(-) > > diff --git a/Documentation/hwmon/lm75 b/Documentation/hwmon/lm75 > index a179040..8d40d0f 100644 > --- a/Documentation/hwmon/lm75 > +++ b/Documentation/hwmon/lm75 > @@ -32,6 +32,11 @@ Supported chips: > Addresses scanned: I2C 0x48 - 0x4f > Datasheet: Publicly available at the Microchip website > http://www.microchip.com/ > + * Analog Devices ADT75 > + Prefix: 'adt75' > + Addresses scanned: I2C 0x48 - 0x4f > + Datasheet: Publicly available at the Analog Devices website > + http://www.analog.com/adt75 > > Author: Frodo Looijaard <frodol@xxxxxx> > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 0b62c3c..497fd14 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -531,6 +531,7 @@ config SENSORS_LM75 > If you say yes here you get support for one common type of > temperature sensor chip, with models including: > > + - Analog Devices ADT75 > - Dallas Semiconductor DS75 and DS1775 > - Maxim MAX6625 and MAX6626 > - Microchip MCP980x > diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c > index ef902d5..0f0291c 100644 > --- a/drivers/hwmon/lm75.c > +++ b/drivers/hwmon/lm75.c > @@ -35,6 +35,7 @@ > */ > > enum lm75_type { /* keep sorted in alphabetical order */ > + adt75, > ds1775, > ds75, > lm75, > @@ -213,6 +214,7 @@ static int lm75_remove(struct i2c_client *client) > } > > static const struct i2c_device_id lm75_ids[] = { > + { "adt75", adt75, }, > { "ds1775", ds1775, }, > { "ds75", ds75, }, > { "lm75", lm75, }, > @@ -241,7 +243,7 @@ static int lm75_detect(struct i2c_client *new_client, > struct i2c_adapter *adapter = new_client->adapter; > int i; > int conf, hyst, os; > - bool is_lm75a = 0; > + bool is_lm75a = 0, is_adt75 = 0; > > if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | > I2C_FUNC_SMBUS_WORD_DATA)) > @@ -259,7 +261,15 @@ static int lm75_detect(struct i2c_client *new_client, > LM75s. It has an ID byte of 0xaX (where X is the chip > revision, with 1 being the only revision in existence) in > register 7, and unused registers return 0xff rather than the > - last read value. */ > + last read value. > + > + The Analog Devices ADT75 has an additional register at 0x04 > + for initiating oneshot captures. It is not actively used in > + this driver but we must avoid assuming it will behave as > + 0x05-0x07 do and return the last read value. In fact register 0x04 > + reads the same as register 0x00. And all registers are repetitive > + mirrored around register 0x04. > + */ > > /* Unused bits */ > conf = i2c_smbus_read_byte_data(new_client, 1); > @@ -277,7 +287,16 @@ static int lm75_detect(struct i2c_client *new_client, > is_lm75a = 1; > hyst = i2c_smbus_read_byte_data(new_client, 2); > os = i2c_smbus_read_byte_data(new_client, 3); > - } else { /* Traditional style LM75 detection */ > + } else { /* ADT75 detection: mirrored registers */ > + os = i2c_smbus_read_byte_data(new_client, 3); > + hyst = i2c_smbus_read_byte_data(new_client, 2); > + if (i2c_smbus_read_byte_data(new_client, 7) == os > + || i2c_smbus_read_byte_data(new_client, 11) == os > + || i2c_smbus_read_byte_data(new_client, 15) == os) > + is_adt75 = 1; > + } > + > + if (!is_lm75a && !is_adt75) { /* Traditional style LM75 detection */ > /* Unused addresses */ > hyst = i2c_smbus_read_byte_data(new_client, 2); > if (i2c_smbus_read_byte_data(new_client, 4) != hyst > @@ -304,7 +323,10 @@ static int lm75_detect(struct i2c_client *new_client, > return -ENODEV; > } > > - strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE); > + if (!is_adt75) > + strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE); > + else > + strlcpy(info->type, "adt75", I2C_NAME_SIZE); > > return 0; > } _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
