diff options
| author | Christian Lamparter <chunkeey@gmail.com> | 2022-02-18 10:06:43 +0100 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2022-02-27 17:03:19 -0800 |
| commit | cd929672a9ef644aca12de59a75de5f061d5983d (patch) | |
| tree | 1a6fc95a69ac7054e7e17f099603938c9e0cd2ea /drivers/hwmon/lm70.c | |
| parent | 64b631fb0c6f7e5fbbe0d641556e07e7a8a272ef (diff) | |
hwmon: (lm70) Add ti,tmp125 support
The TMP125 is a 2 degree Celsius accurate Digital
Temperature Sensor with a SPI interface.
The temperature register is a 16-bit, read-only register.
The MSB (Bit 15) is a leading zero and never set. Bits 14
to 5 are the 1+9 temperature data bits in a two's
complement format. Bits 4 to 0 are useless copies of
Bit 5 value and therefore ignored.
This was tested on a Aerohive HiveAP-350.
Bonus: lm70 supports TMP122/TMP124 as well.
I added them to the Kconfig module description.
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Link: https://lore.kernel.org/r/43b19cbd4e7f51e9509e561b02b5d8d0e7079fac.1645175187.git.chunkeey@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/lm70.c')
| -rw-r--r-- | drivers/hwmon/lm70.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/hwmon/lm70.c b/drivers/hwmon/lm70.c index d2a60de5b8de..c20a749fc7f2 100644 --- a/drivers/hwmon/lm70.c +++ b/drivers/hwmon/lm70.c @@ -34,6 +34,7 @@ #define LM70_CHIP_LM71 2 /* NS LM71 */ #define LM70_CHIP_LM74 3 /* NS LM74 */ #define LM70_CHIP_TMP122 4 /* TI TMP122/TMP124 */ +#define LM70_CHIP_TMP125 5 /* TI TMP125 */ struct lm70 { struct spi_device *spi; @@ -87,6 +88,12 @@ static ssize_t temp1_input_show(struct device *dev, * LM71: * 14 bits of 2's complement data, discard LSB 2 bits, * resolution 0.0312 degrees celsius. + * + * TMP125: + * MSB/D15 is a leading zero. D14 is the sign-bit. This is + * followed by 9 temperature bits (D13..D5) in 2's complement + * data format with a resolution of 0.25 degrees celsius per unit. + * LSB 5 bits (D4..D0) share the same value as D5 and get discarded. */ switch (p_lm70->chip) { case LM70_CHIP_LM70: @@ -102,6 +109,10 @@ static ssize_t temp1_input_show(struct device *dev, case LM70_CHIP_LM71: val = ((int)raw / 4) * 3125 / 100; break; + + case LM70_CHIP_TMP125: + val = (sign_extend32(raw, 14) / 32) * 250; + break; } status = sprintf(buf, "%d\n", val); /* millidegrees Celsius */ @@ -136,6 +147,10 @@ static const struct of_device_id lm70_of_ids[] = { .data = (void *) LM70_CHIP_TMP122, }, { + .compatible = "ti,tmp125", + .data = (void *) LM70_CHIP_TMP125, + }, + { .compatible = "ti,lm71", .data = (void *) LM70_CHIP_LM71, }, @@ -184,6 +199,7 @@ static const struct spi_device_id lm70_ids[] = { { "lm70", LM70_CHIP_LM70 }, { "tmp121", LM70_CHIP_TMP121 }, { "tmp122", LM70_CHIP_TMP122 }, + { "tmp125", LM70_CHIP_TMP125 }, { "lm71", LM70_CHIP_LM71 }, { "lm74", LM70_CHIP_LM74 }, { }, |