[PATCH v6 02/15] i2c: acpi: Use acpi_dev_ready_for_enumeration() helper

Hans de Goede
2021-11-25T16:56:37Z

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@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
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 92c1cc07ed46..04338cbd08a9 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;

--
2.33.1