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bp4f_tmp401: drop i2c auto-detection address list#22

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drop-i2c-autodetect-address-list
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bp4f_tmp401: drop i2c auto-detection address list#22
Scott8440 wants to merge 1 commit into
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drop-i2c-autodetect-address-list

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bp4f_tmp401 registers with legacy i2c class-based auto-detection (.class = I2C_CLASS_HWMON, .detect, .address_list = normal_i2c). At module load i2c_detect() probes every address in normal_i2c[] on every HWMON-class adapter, including the on-CPU Intel iSMT SMBus (i2c-0). That bus is unused/unresponsive on our switches, so each probe blocks for the full iSMT completion timeout (~1s), adding ~7s of "ismt_smbus ... completion wait timed out" to module load.

The sensor is always instantiated explicitly by platform_manager (via new_device, matched by id_table/of_match), so address-list auto-detection is never needed. Remove normal_i2c[] and the .address_list reference; i2c_detect() now early-returns, eliminating the scan. .detect/.class are left in place but inert.

bp4f_tmp401 registers with legacy i2c class-based auto-detection
(.class = I2C_CLASS_HWMON, .detect, .address_list = normal_i2c). At module
load i2c_detect() probes every address in normal_i2c[] on every HWMON-class
adapter, including the on-CPU Intel iSMT SMBus (i2c-0). That bus is
unused/unresponsive on our switches, so each probe blocks for the full iSMT
completion timeout (~1s), adding ~7s of "ismt_smbus ... completion wait
timed out" to module load.

The sensor is always instantiated explicitly by platform_manager (via
new_device, matched by id_table/of_match), so address-list auto-detection is
never needed. Remove normal_i2c[] and the .address_list reference;
i2c_detect() now early-returns, eliminating the scan. .detect/.class are
left in place but inert.
@meta-cla meta-cla Bot added the CLA Signed This label is managed by the Meta Open Source bot. label Jun 17, 2026
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