On Mon, Dec 26, 2016 at 12:25:19AM +0100, Rafael J. Wysocki wrote: > CC Mika and Andy. > > Plus I don't think -stable is going to take your patches directly. > > On Sun, Dec 25, 2016 at 11:21 AM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote: > > The firmware on some cherrytrail devices wrongly adds _ADR 0 to their > > entry describing the 80860F14 uid "2" sd-controller. > > > > I believe the firmware writers intended this as a sdio function address, > > but it is in the wrong place for this, so it gets interpreted as a pci > > address, causing the node describing the sd-controller used for the > > sdio-wifi to get seen as a firmware_node for the pci host bridge, rather > > then being stand-alone device. > > > > This commit adds a byt_sdio_setup function which detects this scenario > > and removes the wrong firmware_node link from the pci host bridge, which > > fixes acpi_create_platform_device returning NULL, leading to non-working > > sdio-wifi. > > > > BugLink: https://github.com/hadess/rtl8723bs/issues/80 > > Cc: stable@xxxxxxxxxxxxxxx > > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> > > --- > > drivers/acpi/acpi_lpss.c | 30 ++++++++++++++++++++++++++++++ > > 1 file changed, 30 insertions(+) > > > > diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c > > index 373657f..df9cc66 100644 > > --- a/drivers/acpi/acpi_lpss.c > > +++ b/drivers/acpi/acpi_lpss.c > > @@ -84,6 +84,7 @@ static const struct lpss_device_desc lpss_dma_desc = { > > }; > > > > struct lpss_private_data { > > + struct acpi_device *adev; > > void __iomem *mmio_base; > > resource_size_t mmio_size; > > unsigned int fixed_clk_rate; > > @@ -154,6 +155,33 @@ static void byt_i2c_setup(struct lpss_private_data *pdata) > > writel(0, pdata->mmio_base + LPSS_I2C_ENABLE); > > } > > > > +static void byt_sdio_setup(struct lpss_private_data *pdata) > > +{ > > + unsigned long long adr; > > + acpi_status status; > > + struct device *dev; > > + > > + /* > > + * Some firmware has a broken _ADR 0 enter for the 80860F14:2 > > + * device, which causes it to get seen as the firmware_node > > + * for the pci host bridge, rather then a stand alone device. > > + * > > + * Check if this is the case, and if it is remove the link. > > + */ > > + if (strcmp(acpi_device_uid(pdata->adev), "2") != 0) > > + return; > > + > > + status = acpi_evaluate_integer(pdata->adev->handle, "_ADR", NULL, &adr); > > + if (ACPI_FAILURE(status) || adr != 0) > > + return; > > + > > + dev = acpi_get_first_physical_node(pdata->adev); > > + if (!dev) > > + return; > > + > > + acpi_unbind_one(dev); > > +} IIRC the _ADR 0 problem is not only limited to SDIO devices. I think we should just fix the match heuristics in acpi_find_child_device() to cover all other devices as well. Something like below might do the job. diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 5ea5dc219f56..7cfd48f55b6f 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -85,7 +85,7 @@ static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) static int find_child_checks(struct acpi_device *adev, bool check_children) { - bool sta_present = true; + bool hid_present, sta_present = true; unsigned long long sta; acpi_status status; @@ -98,7 +98,22 @@ static int find_child_checks(struct acpi_device *adev, bool check_children) if (check_children && list_empty(&adev->children)) return -ENODEV; - return sta_present ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; + /* + * If there is a _HID or _CID present on a bus that is supposed to + * be matched using _ADR, we prioritize those devices without ID + * higher. + * + * This is because there are many BIOSes out there having ACPI + * enumerated devices and the _ADR is set to 0. This will match the + * root PCI bridge to the first found device with _ADR 0 which is + * not always the right device. + */ + hid_present = !list_empty(&adev->pnp.ids); + + if (sta_present) + return hid_present ? FIND_CHILD_MIN_SCORE : FIND_CHILD_MAX_SCORE; + + return FIND_CHILD_MIN_SCORE; } struct acpi_device *acpi_find_child_device(struct acpi_device *parent, -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html