diff mbox series

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

Message ID 20211125165412.535063-3-hdegoede@redhat.com (mailing list archive)
State Not Applicable, archived
Headers show
Series Add support for X86/ACPI camera sensor/PMIC setup with clk and regulator platform data | expand

Commit Message

Hans de Goede Nov. 25, 2021, 4:53 p.m. UTC 
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(-)

Comments

Mika Westerberg Nov. 26, 2021, 7:16 a.m. UTC | #1 
On Thu, Nov 25, 2021 at 05:53:59PM +0100, Hans de Goede wrote:
> 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>

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
diff mbox series

Patch

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;