Re: [PATCH V9 04/11] iio: imu: inv_icm42607: Add I2C and SPI For icm42607

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Missing power-up delay after enabling the `vdd` regulator and before obtaining/enabling the `vddio` regulator.
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commit f54ebd503e69aebf3524a2526c6611126af82da8
Author: Chris Morgan <macromorgan@hotmail.com>

iio: imu: inv_icm42607: Add I2C and SPI For icm42607

This commit adds I2C and SPI driver support for InvenSense ICM-42607 devices.
It includes the necessary Kconfig and Makefile additions to allow building
the module.

> diff --git a/drivers/iio/imu/inv_icm42607/inv_icm42607_i2c.c b/drivers/iio/imu/inv_icm42607/inv_icm42607_i2c.c
> new file mode 100644
> index 0000000000000..22ac51108cd3b
> --- /dev/null
> +++ b/drivers/iio/imu/inv_icm42607/inv_icm42607_i2c.c

[ ... ]

> +static int inv_icm42607_probe(struct i2c_client *client)
> +{
> +	const struct inv_icm42607_hw *hw;
> +	struct regmap *regmap;
> +
> +	hw = i2c_get_match_data(client);
> +	if (!hw)
> +		return dev_err_probe(&client->dev, -ENODEV,
> +				     "Failed to get i2c data\n");
> +
> +	regmap = devm_regmap_init_i2c(client, &inv_icm42607_regmap_config);
> +	if (IS_ERR(regmap))
> +		return dev_err_probe(&client->dev, PTR_ERR(regmap),
> +				     "Failed to register i2c regmap %ld\n",
> +				     PTR_ERR(regmap));
> +
> +	return inv_icm42607_core_probe(regmap, hw, inv_icm42607_i2c_bus_setup);
> +}

[Severity: Medium]
Does inv_icm42607_core_probe() need a power-up stabilization delay after
enabling the vdd regulator?

Looking at inv_icm42607_core_probe() in inv_icm42607_core.c, the vdd and
vddio regulators are enabled sequentially without an intervening delay:

	ret = devm_regulator_get_enable(dev, "vdd");
	if (ret)
		return dev_err_probe(dev, ret,
				     "Failed to get vdd regulator\n");

	st->vddio_supply = devm_regulator_get(dev, "vddio");
	if (IS_ERR(st->vddio_supply))
		return dev_err_probe(dev, PTR_ERR(st->vddio_supply),
				     "Failed to get vddio regulator\n");

	ret = inv_icm42607_enable_vddio_reg(st);

Other sensors in this family, such as the icm42600 and icm45600, typically
require a delay before vddio can be applied. Could omitting this delay
cause hardware initialization failures or latch-up on platforms where vddio
ramps up before vdd is fully stable?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260530031739.109063-1-macroalpha82@gmail.com?part=4