[PATCH 4.6 032/100] mmc: sdhci-acpi: Ensure connected devices are powered when probing

From: Greg Kroah-Hartman
Date: Mon May 30 2016 - 17:20:26 EST

4.6-stable review patch. If anyone has any objections, please let me know.


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

commit e5bbf30733f930a1d17b4ccf19eac88e30a39cc7 upstream.

Some devices connected to the SDHCI controller may have separate enabling
lines that are controlled through GPIO. These devices need to be powered
on and enabled before probing. This is to ensure all devices connected can
be seen by the controller.

Note, for "stable" this patch depends on the following change:
commit 78a898d0e395 ("ACPI / PM: Export acpi_device_fix_up_power()")

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Reported-and-tested-by: Laszlo Fiat <laszlo.fiat@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Reported-by: Laszlo Fiat <laszlo.fiat@xxxxxxxxx>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112571
Link: http://lkml.kernel.org/r/CA+7w51inLtQSr656bJvOjGG9oQWKYPXH+xxDPJKbeJ=CcrkS9Q@xxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/mmc/host/sdhci-acpi.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -381,7 +381,7 @@ static int sdhci_acpi_probe(struct platf
struct device *dev = &pdev->dev;
acpi_handle handle = ACPI_HANDLE(dev);
- struct acpi_device *device;
+ struct acpi_device *device, *child;
struct sdhci_acpi_host *c;
struct sdhci_host *host;
struct resource *iomem;
@@ -393,6 +393,11 @@ static int sdhci_acpi_probe(struct platf
if (acpi_bus_get_device(handle, &device))
return -ENODEV;

+ /* Power on the SDHCI controller and its children */
+ acpi_device_fix_up_power(device);
+ list_for_each_entry(child, &device->children, node)
+ acpi_device_fix_up_power(child);
if (acpi_bus_get_status(device) || !device->status.present)
return -ENODEV;