Intel's BXT devices need to execute a _DSM method
during {runtime_,}{suspend,resume} in order to get a
chunk of dwc3 to power gate and save some extra
power.
Let's do that now.
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
---
drivers/usb/dwc3/Kconfig | 2 +-
drivers/usb/dwc3/dwc3-pci.c | 73 +++++++++++++++++++++++++++++++++++++--------
2 files changed, 62 insertions(+), 13 deletions(-)
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index a45b4f1ba689..c5aa235863e8 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -70,7 +70,7 @@ config USB_DWC3_EXYNOS
config USB_DWC3_PCI
tristate "PCIe-based Platforms"
- depends on PCI
+ depends on PCI && ACPI
default USB_DWC3
help
If you're using the DesignWare Core IP with a PCIe, please say
diff --git a/drivers/usb/dwc3/dwc3-pci.c b/drivers/usb/dwc3/dwc3-pci.c
index 0f54b8166e54..8c39ec6522fd 100644
--- a/drivers/usb/dwc3/dwc3-pci.c
+++ b/drivers/usb/dwc3/dwc3-pci.c
@@ -39,14 +39,25 @@
#define PCI_DEVICE_ID_INTEL_APL 0x5aaa
#define PCI_DEVICE_ID_INTEL_KBP 0xa2b0
+#define PCI_INTEL_BXT_DSM_UUID "732b85d5-b7a7-4a1b-9ba0-4bbd00ffd511"
+#define PCI_INTEL_BXT_FUNC_PMU_PWR 4
+#define PCI_INTEL_BXT_STATE_D0 0
+#define PCI_INTEL_BXT_STATE_D3 3
+
/**
* struct dwc3_pci - Driver private structure
* @dwc3: child dwc3 platform_device
* @pci: our link to PCI bus
+ * @uuid: _DSM UUID
+ * @has_dsm_for_pm: true for devices which need to run _DSM on runtime PM
*/
struct dwc3_pci {
struct platform_device *dwc3;
struct pci_dev *pci;
+
+ u8 uuid[16];
+
+ unsigned int has_dsm_for_pm:1;
};
static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
@@ -102,6 +113,12 @@ static int dwc3_pci_quirks(struct dwc3_pci *dwc)
if (ret < 0)
return ret;
+ if (pdev->device == PCI_DEVICE_ID_INTEL_BXT ||
+ pdev->device == PCI_DEVICE_ID_INTEL_BXT_M) {
+ acpi_str_to_uuid(PCI_INTEL_BXT_DSM_UUID, dwc->uuid);
+ dwc->has_dsm_for_pm = true;
+ }
+
if (pdev->device == PCI_DEVICE_ID_INTEL_BYT) {
struct gpio_desc *gpio;
@@ -149,6 +166,30 @@ static int dwc3_pci_quirks(struct dwc3_pci *dwc)
return 0;
}
+static int dwc3_pci_dsm(struct dwc3_pci *dwc, int param)
+{
+ union acpi_object *obj;
+ union acpi_object tmp;
+ union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(1, &tmp);
+
+ if (!dwc->has_dsm_for_pm)
+ return 0;
+
+ tmp.type = ACPI_TYPE_INTEGER;
+ tmp.integer.value = param;
+
+ obj = acpi_evaluate_dsm(ACPI_HANDLE(&dwc->pci->dev), dwc->uuid,
+ 1, PCI_INTEL_BXT_FUNC_PMU_PWR, &argv4);
+ if (!obj) {
+ dev_err(&dwc->pci->dev, "failed to evaluate _DSM\n");
+ return -EIO;
+ }
+
+ ACPI_FREE(obj);
+
+ return 0;
+}
+
static int dwc3_pci_probe(struct pci_dev *pci,
const struct pci_device_id *id)
{
@@ -255,8 +296,10 @@ MODULE_DEVICE_TABLE(pci, dwc3_pci_id_table);
#ifdef CONFIG_PM
static int dwc3_pci_runtime_suspend(struct device *dev)
{
+ struct dwc3_pci *dwc = dev_get_drvdata(dev);
+
if (device_run_wake(dev))
- return 0;
+ return dwc3_pci_dsm(dwc, PCI_INTEL_BXT_STATE_D3);
return -EBUSY;
}
@@ -265,28 +308,34 @@ static int dwc3_pci_runtime_resume(struct device *dev)
{
struct dwc3_pci *dwc = dev_get_drvdata(dev);
struct platform_device *dwc3 = dwc->dwc3;
+ int ret;
+
+ ret = dwc3_pci_dsm(dwc, PCI_INTEL_BXT_STATE_D0);
+ if (ret)
+ return ret;
return pm_runtime_get(&dwc3->dev);
}
#endif /* CONFIG_PM */
#ifdef CONFIG_PM_SLEEP
-static int dwc3_pci_pm_dummy(struct device *dev)
+static int dwc3_pci_suspend(struct device *dev)
{
- /*
- * There's nothing to do here. No, seriously. Everything is either taken
- * care either by PCI subsystem or dwc3/core.c, so we have nothing
- * missing here.
- *
- * So you'd think we didn't need this at all, but PCI subsystem will
- * bail out if we don't have a valid callback :-s
- */
- return 0;
+ struct dwc3_pci *dwc = dev_get_drvdata(dev);
+
+ return dwc3_pci_dsm(dwc, PCI_INTEL_BXT_STATE_D3);
+}
+
+static int dwc3_pci_resume(struct device *dev)
+{
+ struct dwc3_pci *dwc = dev_get_drvdata(dev);
+
+ return dwc3_pci_dsm(dwc, PCI_INTEL_BXT_STATE_D0);
}
#endif /* CONFIG_PM_SLEEP */
static struct dev_pm_ops dwc3_pci_dev_pm_ops = {
- SET_SYSTEM_SLEEP_PM_OPS(dwc3_pci_pm_dummy, dwc3_pci_pm_dummy)
+ SET_SYSTEM_SLEEP_PM_OPS(dwc3_pci_suspend, dwc3_pci_resume)
SET_RUNTIME_PM_OPS(dwc3_pci_runtime_suspend, dwc3_pci_runtime_resume,
NULL)
};
--
2.10.1
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