From: Josh Lehan krellan@google.com
[ Upstream commit 229d495d8189ae785dacee72e5633a58edc25ddf ]
Add support for the Maxim MAX6654 to the lm90 driver.
The MAX6654 is a temperature sensor, similar to the others, but with some differences regarding the configuration register, and the sampling rate at which extended resolution becomes possible.
Signed-off-by: Josh Lehan krellan@google.com Link: https://lore.kernel.org/r/20200513184248.145765-1-krellan@google.com Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Sasha Levin sashal@kernel.org --- Documentation/hwmon/lm90.rst | 23 ++++++++++++++++-- drivers/hwmon/Kconfig | 9 ++++---- drivers/hwmon/lm90.c | 45 ++++++++++++++++++++++++++++++++---- 3 files changed, 67 insertions(+), 10 deletions(-)
diff --git a/Documentation/hwmon/lm90.rst b/Documentation/hwmon/lm90.rst index 953315987c06e..78dfc01b47a23 100644 --- a/Documentation/hwmon/lm90.rst +++ b/Documentation/hwmon/lm90.rst @@ -123,6 +123,18 @@ Supported chips:
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+ * Maxim MAX6654 + + Prefix: 'max6654' + + Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, + + 0x4c, 0x4d and 0x4e + + Datasheet: Publicly available at the Maxim website + + https://www.maximintegrated.com/en/products/sensors/MAX6654.html + * Maxim MAX6657
Prefix: 'max6657' @@ -301,6 +313,13 @@ ADT7461, ADT7461A, NCT1008: * Extended temperature range (breaks compatibility) * Lower resolution for remote temperature
+MAX6654: + * Better local resolution + * Selectable address + * Remote sensor type selection + * Extended temperature range + * Extended resolution only available when conversion rate <= 1 Hz + MAX6657 and MAX6658: * Better local resolution * Remote sensor type selection @@ -336,8 +355,8 @@ SA56004X:
All temperature values are given in degrees Celsius. Resolution is 1.0 degree for the local temperature, 0.125 degree for the remote -temperature, except for the MAX6657, MAX6658 and MAX6659 which have a -resolution of 0.125 degree for both temperatures. +temperature, except for the MAX6654, MAX6657, MAX6658 and MAX6659 which have +a resolution of 0.125 degree for both temperatures.
Each sensor has its own high and low limits, plus a critical limit. Additionally, there is a relative hysteresis value common to both critical diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 13a6b4afb4b36..fdf8fab7eb396 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1132,10 +1132,11 @@ config SENSORS_LM90 help If you say yes here you get support for National Semiconductor LM90, LM86, LM89 and LM99, Analog Devices ADM1032, ADT7461, and ADT7461A, - Maxim MAX6646, MAX6647, MAX6648, MAX6649, MAX6657, MAX6658, MAX6659, - MAX6680, MAX6681, MAX6692, MAX6695, MAX6696, ON Semiconductor NCT1008, - Winbond/Nuvoton W83L771W/G/AWG/ASG, Philips SA56004, GMT G781, and - Texas Instruments TMP451 sensor chips. + Maxim MAX6646, MAX6647, MAX6648, MAX6649, MAX6654, MAX6657, MAX6658, + MAX6659, MAX6680, MAX6681, MAX6692, MAX6695, MAX6696, + ON Semiconductor NCT1008, Winbond/Nuvoton W83L771W/G/AWG/ASG, + Philips SA56004, GMT G781, and Texas Instruments TMP451 + sensor chips.
This driver can also be built as a module. If so, the module will be called lm90. diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c index 6d6f543baea68..9d48a7405932f 100644 --- a/drivers/hwmon/lm90.c +++ b/drivers/hwmon/lm90.c @@ -35,6 +35,14 @@ * explicitly as max6659, or if its address is not 0x4c. * These chips lack the remote temperature offset feature. * + * This driver also supports the MAX6654 chip made by Maxim. This chip can + * be at 9 different addresses, similar to MAX6680/MAX6681. The MAX6654 is + * otherwise similar to MAX6657/MAX6658/MAX6659. Extended range is available + * by setting the configuration register accordingly, and is done during + * initialization. Extended precision is only available at conversion rates + * of 1 Hz and slower. Note that extended precision is not enabled by + * default, as this driver initializes all chips to 2 Hz by design. + * * This driver also supports the MAX6646, MAX6647, MAX6648, MAX6649 and * MAX6692 chips made by Maxim. These are again similar to the LM86, * but they use unsigned temperature values and can report temperatures @@ -94,8 +102,8 @@ * have address 0x4d. * MAX6647 has address 0x4e. * MAX6659 can have address 0x4c, 0x4d or 0x4e. - * MAX6680 and MAX6681 can have address 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, - * 0x4c, 0x4d or 0x4e. + * MAX6654, MAX6680, and MAX6681 can have address 0x18, 0x19, 0x1a, 0x29, + * 0x2a, 0x2b, 0x4c, 0x4d or 0x4e. * SA56004 can have address 0x48 through 0x4F. */
@@ -104,7 +112,7 @@ static const unsigned short normal_i2c[] = { 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680, - max6646, w83l771, max6696, sa56004, g781, tmp451 }; + max6646, w83l771, max6696, sa56004, g781, tmp451, max6654 };
/* * The LM90 registers @@ -145,7 +153,7 @@ enum chips { lm90, adm1032, lm99, lm86, max6657, max6659, adt7461, max6680, #define LM90_REG_R_TCRIT_HYST 0x21 #define LM90_REG_W_TCRIT_HYST 0x21
-/* MAX6646/6647/6649/6657/6658/6659/6695/6696 registers */ +/* MAX6646/6647/6649/6654/6657/6658/6659/6695/6696 registers */
#define MAX6657_REG_R_LOCAL_TEMPL 0x11 #define MAX6696_REG_R_STATUS2 0x12 @@ -209,6 +217,7 @@ static const struct i2c_device_id lm90_id[] = { { "max6646", max6646 }, { "max6647", max6646 }, { "max6649", max6646 }, + { "max6654", max6654 }, { "max6657", max6657 }, { "max6658", max6657 }, { "max6659", max6659 }, @@ -269,6 +278,10 @@ static const struct of_device_id __maybe_unused lm90_of_match[] = { .compatible = "dallas,max6649", .data = (void *)max6646 }, + { + .compatible = "dallas,max6654", + .data = (void *)max6654 + }, { .compatible = "dallas,max6657", .data = (void *)max6657 @@ -367,6 +380,11 @@ static const struct lm90_params lm90_params[] = { .max_convrate = 6, .reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL, }, + [max6654] = { + .alert_alarms = 0x7c, + .max_convrate = 7, + .reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL, + }, [max6657] = { .flags = LM90_PAUSE_FOR_CONFIG, .alert_alarms = 0x7c, @@ -1556,6 +1574,16 @@ static int lm90_detect(struct i2c_client *client, && (config1 & 0x3f) == 0x00 && convrate <= 0x07) { name = "max6646"; + } else + /* + * The chip_id of the MAX6654 holds the revision of the chip. + * The lowest 3 bits of the config1 register are unused and + * should return zero when read. + */ + if (chip_id == 0x08 + && (config1 & 0x07) == 0x00 + && convrate <= 0x07) { + name = "max6654"; } } else if (address == 0x4C @@ -1659,6 +1687,15 @@ static int lm90_init_client(struct i2c_client *client, struct lm90_data *data) if (data->kind == max6680) config |= 0x18;
+ /* + * Put MAX6654 into extended range (0x20, extend minimum range from + * 0 degrees to -64 degrees). Note that extended resolution is not + * possible on the MAX6654 unless conversion rate is set to 1 Hz or + * slower, which is intentionally not done by default. + */ + if (data->kind == max6654) + config |= 0x20; + /* * Select external channel 0 for max6695/96 */