Re: [PATCH v9 8/9] regulator: Add MediaTek MT6392 regulator

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The driver mutates the statically allocated global array `mt6392_regulators` during probe, causing data races and breaking support for multiple PMIC instances.
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--- Patch [8]: [PATCH v9 8/9] regulator: Add MediaTek MT6392 regulator ---

commit 942bc64d63d9355df7d6368a340ca5b124e3e738
Author: Fabien Parent [off-list ref]

regulator: Add MediaTek MT6392 regulator

This patch introduces a new regulator driver for the MediaTek MT6392 PMIC.
It provides support for various power rails, including buck and LDO
regulators, controlled via regmap.

[ ... ]

+static int mt6392_set_buck_vsel_reg(struct platform_device *pdev)
+{
+	struct mt6397_chip *mt6392 = dev_get_drvdata(pdev->dev.parent);
+	int i;
+	u32 regval;
+
+	for (i = 0; i < MT6392_MAX_REGULATOR; i++) {
+		if (mt6392_regulators[i].vselctrl_reg) {
+			// Read the vselctrl_reg register
+			if (regmap_read(mt6392->regmap,
+					mt6392_regulators[i].vselctrl_reg,
+					&regval) < 0) {
+				dev_err(&pdev->dev,
+					"Failed to read buck ctrl\n");
+				return -EIO;
+			}
+
+			// vselctrl_reg[vselctrl_mask] defines the mode
+			if (regval & mt6392_regulators[i].vselctrl_mask) {
+				// Regulator in Normal mode
+				mt6392_regulators[i].desc.vsel_reg =
+					mt6392_regulators[i].vsel_normal_mode_reg;
+				mt6392_regulators[i].desc.vsel_mask =
+					mt6392_regulators[i].vsel_normal_mode_mask;

[Severity: Medium]
Will this corrupt the configuration for previously registered devices if
multiple MT6392 PMIC instances are present?

This modifies the statically allocated global array mt6392_regulators based on
per-instance hardware state. Because the regulator core keeps a pointer to the
provided desc, mutating it here affects all instances of the PMIC in the
system.

+			} else {
+				// Regulator in Register mode
+				mt6392_regulators[i].desc.vsel_reg =
+					mt6392_regulators[i].vsel_reg_mode_reg;
+				mt6392_regulators[i].desc.vsel_mask =
+					mt6392_regulators[i].vsel_reg_mode_mask;
+			}
+		}
+	}
+
+	return 0;
+}

[ ... ]

+static struct platform_driver mt6392_regulator_driver = {
+	.driver = {
+		.name = "mt6392-regulator",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,

[Severity: Medium]
Does enabling asynchronous probing introduce a data race with the global array
modifications above?

If multiple PMIC instances are probed concurrently, they will race to overwrite
the vsel_reg and vsel_mask fields of the shared global mt6392_regulators array
in mt6392_set_buck_vsel_reg().

+	},
+	.probe = mt6392_regulator_probe,
+	.id_table = mt6392_platform_ids,
+};

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Sashiko AI review · https://sashiko.dev/#/patchset/20260820122242.120039-1-l.scorcia@gmail.com?part=8