Re: [PATCH v3] hwmon: (lm75) Add support for Nuvoton NCT7715
From: sashiko-bot@kernel.org
Date: 2026-09-15 05:28:43
Also in:
linux-hwmon
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Medium] hwmon: lm75: NCT7715 initialization fails to clear bit 14 of config register -- commit 7bd04866b8e88a3003be284539483cdda6599844 Author: Sheng-Yuan Huang [off-list ref] hwmon: (lm75) Add support for Nuvoton NCT7715 This commit adds support for the Nuvoton NCT7715 temperature sensor to the lm75 hardware monitoring driver. It introduces a new device parameter entry that reuses much of the TMP112 handling for configuration and alarms.
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diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c --- a/drivers/hwmon/lm75.c +++ b/drivers/hwmon/lm75.c
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@@ -259,6 +260,16 @@ static const struct lm75_params device_params[] = { .sample_times = (unsigned int []){ 30, 60, 120, 240 }, .resolutions = (u8 []) {9, 10, 11, 12 }, }, + [nct7715] = { + .config_reg_16bits = true, + .set_mask = 0x8060, /* 12-bit mode, 4 samples / second */ + .clr_mask = 1 << 7, /* no one-shot mode */
[Severity: Medium] Will this leave bit 14 unchanged if it was previously set by a bootloader or left over from a warm reboot? During driver probe, lm75_generic_probe() calls lm75_write_config() to initialize LM75_REG_CONF. The regmap update mask used is: clr_mask | set_mask | LM75_SHUTDOWN For nct7715, set_mask is 0x8060 and clr_mask is 0x0080. Bit 14 (0x4000) is missing from both masks. Because of this, regmap_update_bits() will silently ignore the 0 in bit 14 of set_mask and preserve its prior value from the hardware configuration register. If bit 14 remains set, can the sensor operate at 8 Hz instead of the intended 4 Hz, leading to a mismatch between the hardware state and the driver state which expects and reports a 250ms interval? Should 0x4000 be included in clr_mask to ensure the hardware is properly initialized to 4 samples / second? -- Sashiko AI review · https://sashiko.dev/#/patchset/20260915052021.6959-1-syhuang3@nuvoton.com?part=1