On Wed, Dec 28, 2016 at 10:14 AM, Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> wrote: > 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, > I'd rather only change the return statement, like this: return sta_present && list_empty(&adev->pnp.ids) ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; I'll send a patch tomorrow unless there's something wrong with this. BTW, the comment is not correct too, because the host bridge has a _HID. What is matched against _ADR(0) is the first function on bus 0 IIRC. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
