[PATCH 21/40] hwmon: (lm90) Strengthen chip detection for ADM1032, ADT7461(A), and NCT1008

From: Guenter Roeck
Date: Wed May 25 2022 - 10:01:35 EST


ADT7461A and NCT1008 support the undocumented manufacturer and chip ID
registers at 0x3e and 0x3f, and return 0x61 as chip ID. ADM1032 and
ADT7461 do not support those registers but return 0 when reading them.
Use this information to improve the accuracy of the chip detection code.

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/hwmon/lm90.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index d2477e0c1e1e..abc64738e892 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -1603,22 +1603,26 @@ static const char *lm90_detect_analog(struct i2c_client *client, int chip_id,

switch (chip_id) {
case 0x40 ... 0x4f: /* ADM1032 */
- if ((address == 0x4c || address == 0x4d) && !(config1 & 0x3f) &&
+ if (man_id2 == 0x00 && chip_id2 == 0x00 &&
+ (address == 0x4c || address == 0x4d) && !(config1 & 0x3f) &&
convrate <= 0x0a)
name = "adm1032";
break;
case 0x51: /* ADT7461 */
- if ((address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
+ if (man_id2 == 0x00 && chip_id2 == 0x00 &&
+ (address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
convrate <= 0x0a)
name = "adt7461";
break;
case 0x54: /* NCT1008 */
- if ((address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
+ if (man_id2 == 0x41 && chip_id2 == 0x61 &&
+ (address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
convrate <= 0x0a)
name = "nct1008";
break;
case 0x57: /* ADT7461A, NCT1008 (datasheet rev. 3) */
- if ((address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
+ if (man_id2 == 0x41 && chip_id2 == 0x61 &&
+ (address == 0x4c || address == 0x4d) && !(config1 & 0x1b) &&
convrate <= 0x0a)
name = "adt7461a";
break;
--
2.35.1