On Thu, Mar 22, 2018 at 10:17:02AM +0100, Jean Delvare wrote: > On Wed, 21 Mar 2018 16:04:52 +0100, Alvaro Gamez Machado wrote: > > Maxim MAX663x family are mostly compatible with LM92, but they lack any > > identification register. Weakening the detect function would make it prone > > to false positives, and current one doesn't detect all chips. Therefore, > > the detect function for max6635 devices is removed in favor of explicit > > device instatiation. > > > > Signed-off-by: Alvaro Gamez Machado <[email protected]> > > --- > > Documentation/hwmon/lm92 | 4 +--- > > drivers/hwmon/lm92.c | 58 > > ------------------------------------------------ > > 2 files changed, 1 insertion(+), 61 deletions(-) > > > > diff --git a/Documentation/hwmon/lm92 b/Documentation/hwmon/lm92 > > index 22f68ad032cf..f2a5adcf4ead 100644 > > --- a/Documentation/hwmon/lm92 > > +++ b/Documentation/hwmon/lm92 > > @@ -12,9 +12,7 @@ Supported chips: > > Datasheet: http://www.national.com/pf/LM/LM76.html > > * Maxim MAX6633/MAX6634/MAX6635 > > Prefix: 'lm92' > > - Addresses scanned: I2C 0x48 - 0x4b > > - MAX6633 with address in 0x40 - 0x47, 0x4c - 0x4f needs force parameter > > - and MAX6634 with address in 0x4c - 0x4f needs force parameter > > + Addresses scanned: none, force parameter needed > > Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074 > > > > Authors: > > diff --git a/drivers/hwmon/lm92.c b/drivers/hwmon/lm92.c > > index 2a91974a10bb..18509b5af11e 100644 > > --- a/drivers/hwmon/lm92.c > > +++ b/drivers/hwmon/lm92.c > > @@ -259,62 +259,6 @@ static void lm92_init_client(struct i2c_client *client) > > config & 0xFE); > > } > > > > -/* > > - * The MAX6635 has no identification register, so we have to use tricks > > - * to identify it reliably. This is somewhat slow. > > - * Note that we do NOT rely on the 2 MSB of the configuration register > > - * always reading 0, as suggested by the datasheet, because it was once > > - * reported not to be true. > > - */ > > -static int max6635_check(struct i2c_client *client) > > -{ > > - u16 temp_low, temp_high, temp_hyst, temp_crit; > > - u8 conf; > > - int i; > > - > > - /* > > - * No manufacturer ID register, so a read from this address will > > - * always return the last read value. > > - */ > > - temp_low = i2c_smbus_read_word_data(client, LM92_REG_TEMP_LOW); > > - if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_low) > > - return 0; > > - temp_high = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HIGH); > > - if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_high) > > - return 0; > > - > > - /* Limits are stored as integer values (signed, 9-bit). */ > > - if ((temp_low & 0x7f00) || (temp_high & 0x7f00)) > > - return 0; > > - temp_hyst = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HYST); > > - temp_crit = i2c_smbus_read_word_data(client, LM92_REG_TEMP_CRIT); > > - if ((temp_hyst & 0x7f00) || (temp_crit & 0x7f00)) > > - return 0; > > - > > - /* > > - * Registers addresses were found to cycle over 16-byte boundaries. > > - * We don't test all registers with all offsets so as to save some > > - * reads and time, but this should still be sufficient to dismiss > > - * non-MAX6635 chips. > > - */ > > - conf = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG); > > - for (i = 16; i < 96; i *= 2) { > > - if (temp_hyst != i2c_smbus_read_word_data(client, > > - LM92_REG_TEMP_HYST + i - 16) > > - || temp_crit != i2c_smbus_read_word_data(client, > > - LM92_REG_TEMP_CRIT + i) > > - || temp_low != i2c_smbus_read_word_data(client, > > - LM92_REG_TEMP_LOW + i + 16) > > - || temp_high != i2c_smbus_read_word_data(client, > > - LM92_REG_TEMP_HIGH + i + 32) > > - || conf != i2c_smbus_read_byte_data(client, > > - LM92_REG_CONFIG + i)) > > - return 0; > > - } > > - > > - return 1; > > -} > > - > > static struct attribute *lm92_attrs[] = { > > &sensor_dev_attr_temp1_input.dev_attr.attr, > > &sensor_dev_attr_temp1_crit.dev_attr.attr, > > @@ -348,8 +292,6 @@ static int lm92_detect(struct i2c_client *new_client, > > > > if ((config & 0xe0) == 0x00 && man_id == 0x0180) > > pr_info("lm92: Found National Semiconductor LM92 chip\n"); > > - else if (max6635_check(new_client)) > > - pr_info("lm92: Found Maxim MAX6635 chip\n"); > > else > > return -ENODEV; > > > > Reviewed-by: Jean Delvare <[email protected]> > > It would probably make sense to add prefix "max6635" to lm92_id[] so > that the device can be instantiated by its actual name.
Excellent idea. I took the freedom to add that to the patch. Thanks, Guenter > > -- > Jean Delvare > SUSE L3 Support -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
