[PATCH v4 02/11] i2c: acpi: Use acpi_dev_ready_for_enumeration() helper

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The clk and regulator frameworks expect clk/regulator consumer-devices
to have info about the consumed clks/regulators described in the device's
fw_node.

To work around cases where this info is not present in the firmware tables,
which is often the case on x86/ACPI devices, both frameworks allow the
provider-driver to attach info about consumers to the clks/regulators
when registering these.

This causes problems with the probe ordering wrt drivers for consumers
of these clks/regulators. Since the lookups are only registered when the
provider-driver binds, trying to get these clks/regulators before then
results in a -ENOENT error for clks and a dummy regulator for regulators.

To ensure the correct probe-ordering the ACPI core has code to defer the
enumeration of consumers affected by this until the providers are ready.

Call the new acpi_dev_ready_for_enumeration() helper to avoid
enumerating / instantiating i2c-clients too early.

Acked-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
 drivers/i2c/i2c-core-acpi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 546cc935e035..71eee5bc17ab 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -144,9 +144,12 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,
 	struct list_head resource_list;
 	int ret;
 
-	if (acpi_bus_get_status(adev) || !adev->status.present)
+	if (acpi_bus_get_status(adev))
 		return -EINVAL;
 
+	if (!acpi_dev_ready_for_enumeration(adev))
+		return -ENODEV;
+
 	if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
 		return -ENODEV;
 
-- 
2.31.1




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