From 60c0c6d6d6a5165adf6ee7c3ad8e8942e8b5b91a Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Wed, 26 Jan 2022 16:43:58 +0800 Subject: [PATCH] hwmon: (lm90) Fix usage of CONFIG2 register in detect function stable inclusion from stable-v5.10.89 commit fa2e149260bf90bbbe83dbc1ed9c9113d13d3afd bugzilla: 186140 https://gitee.com/openeuler/kernel/issues/I4S8HA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fa2e149260bf90bbbe83dbc1ed9c9113d13d3afd -------------------------------- [ Upstream commit fce15c45d3fbd9fc1feaaf3210d8e3f8b33dfd3a ] The detect function had a comment "Make compiler happy" when id did not read the second configuration register. As it turns out, the code was checking the contents of this register for manufacturer ID 0xA1 (NXP Semiconductor/Philips), but never actually read the register. So it wasn't surprising that the compiler complained, and it indeed had a point. Fix the code to read the register contents for manufacturer ID 0xa1. At the same time, the code was reading the register for manufacturer ID 0x41 (Analog Devices), but it was not using the results. In effect it was just checking if reading the register returned an error. That doesn't really add much if any value, so stop doing that. Fixes: f90be42fb383 ("hwmon: (lm90) Refactor reading of config2 register") Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin Signed-off-by: Chen Jun Signed-off-by: Zheng Zengkai --- drivers/hwmon/lm90.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c index ebbfd5f352c0..ef55a1486099 100644 --- a/drivers/hwmon/lm90.c +++ b/drivers/hwmon/lm90.c @@ -1438,12 +1438,11 @@ static int lm90_detect(struct i2c_client *client, if (man_id < 0 || chip_id < 0 || config1 < 0 || convrate < 0) return -ENODEV; - if (man_id == 0x01 || man_id == 0x5C || man_id == 0x41) { + if (man_id == 0x01 || man_id == 0x5C || man_id == 0xA1) { config2 = i2c_smbus_read_byte_data(client, LM90_REG_R_CONFIG2); if (config2 < 0) return -ENODEV; - } else - config2 = 0; /* Make compiler happy */ + } if ((address == 0x4C || address == 0x4D) && man_id == 0x01) { /* National Semiconductor */ -- GitLab