Add support for Power Resources for Dx states and the necessary hook

for PCI devices.  This hook should be called twice, before and after
changing the power state of a PCI device.

Before setting the device to the new state, the ACPI layer will notify
every power resources linked to the device for that state and make sure
they are turned "_ON".  After changing the state of the device, it will
decrement the reference of every power resources linked to that device
for the old state and turn them "_OFF" if they are no longer referenced.

This fixes the no-USB after resume problem seen on various ThinkPad,
problem initialy diagnosed with Alexander Polakov.

ok kettenis@, deraadt@

1 files changed, 84 insertions, 8 deletions

diff --git a/sys/dev/acpi/acpi.c b/sys/dev/acpi/acpi.c
index 9d65faa395c..1683dbdc36c 100644
--- a/sys/dev/acpi/acpi.c
+++ b/sys/dev/acpi/acpi.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpi.c,v 1.246 2013/06/01 23:00:16 mlarkin Exp $ */
+/* $OpenBSD: acpi.c,v 1.247 2013/11/06 10:40:36 mpi Exp $ */
 /*
  * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com>
  * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org>
@@ -74,6 +74,7 @@ int	acpi_hasprocfvs;
 
 void 	acpi_pci_match(struct device *, struct pci_attach_args *);
 pcireg_t acpi_pci_min_powerstate(pci_chipset_tag_t, pcitag_t);
+void	 acpi_pci_set_powerstate(pci_chipset_tag_t, pcitag_t, int, int);
 
 int	acpi_match(struct device *, void *, void *);
 void	acpi_attach(struct device *, struct device *, void *);
@@ -559,15 +560,26 @@ void
 acpi_pci_match(struct device *dev, struct pci_attach_args *pa)
 {
 	struct acpi_pci *pdev;
+	int state;
 
 	TAILQ_FOREACH(pdev, &acpi_pcidevs, next) {
-		if (pdev->bus == pa->pa_bus && 
-		    pdev->dev == pa->pa_device && 
-		    pdev->fun == pa->pa_function) {
-			dnprintf(10,"%s at acpi0 %s\n", 
-			    dev->dv_xname, aml_nodename(pdev->node));
-			pdev->device = dev;
-		}
+		if (pdev->bus != pa->pa_bus ||
+		    pdev->dev != pa->pa_device ||
+		    pdev->fun != pa->pa_function)
+			continue;
+
+		dnprintf(10,"%s at acpi0 %s\n", dev->dv_xname,
+		    aml_nodename(pdev->node));
+
+		pdev->device = dev;
+
+		/*
+		 * If some Power Resources are dependent on this device
+		 * initialize them.
+		 */
+		state = pci_get_powerstate(pa->pa_pc, pa->pa_tag);
+		acpi_pci_set_powerstate(pa->pa_pc, pa->pa_tag, state, 1);
+		acpi_pci_set_powerstate(pa->pa_pc, pa->pa_tag, state, 0);
 	}
 }
 
@@ -604,6 +616,66 @@ acpi_pci_min_powerstate(pci_chipset_tag_t pc, pcitag_t tag)
 }
 
 void
+acpi_pci_set_powerstate(pci_chipset_tag_t pc, pcitag_t tag, int state, int pre)
+{
+#if NACPIPWRRES > 0
+	struct acpi_softc *sc = acpi_softc;
+	struct acpi_pwrres *pr;
+	struct acpi_pci *pdev;
+	int bus, dev, fun;
+	char name[5];
+
+	pci_decompose_tag(pc, tag, &bus, &dev, &fun);
+	TAILQ_FOREACH(pdev, &acpi_pcidevs, next) {
+		if (pdev->bus == bus && pdev->dev == dev && pdev->fun == fun)
+			break;
+	}
+
+	/* XXX Add a check to discard nodes without Power Resources? */
+	if (pdev == NULL)
+		return;
+
+	SIMPLEQ_FOREACH(pr, &sc->sc_pwrresdevs, p_next) {
+		if (pr->p_node != pdev->node)
+			continue;
+
+		/*
+		 * If the firmware is already aware that the device
+		 * is in the given state, there's nothing to do.
+		 */
+		if (pr->p_state == state)
+			continue;
+
+		if (pre) {
+			/*
+			 * If a Resource is dependent on this device for
+			 * the given state, make sure it is turned "_ON".
+			 */
+			if (pr->p_res_state == state)
+				acpipwrres_ref_incr(pr->p_res_sc, pr->p_node);
+		} else {
+			/*
+			 * If a Resource was referenced for the state we
+			 * left, drop a reference and turn it "_OFF" if
+			 * it was the last one.
+			 */
+			if (pr->p_res_state == pr->p_state)
+				acpipwrres_ref_decr(pr->p_res_sc, pr->p_node);
+
+			if (pr->p_res_state == state) {
+				snprintf(name, sizeof(name), "_PS%d", state);
+				aml_evalname(sc, pr->p_node, name, 0,
+				    NULL, NULL);
+			}
+
+			pr->p_state = state;
+		}
+
+	}
+#endif /* NACPIPWRRES > 0 */
+}
+
+void
 acpi_pciroots_attach(struct device *dev, void *aux, cfprint_t pr)
 {
 	struct acpi_pci			*pdev;
@@ -658,6 +730,10 @@ acpi_attach(struct device *parent, struct device *self, void *aux)
 
 	SIMPLEQ_INIT(&sc->sc_tables);
 	SIMPLEQ_INIT(&sc->sc_wakedevs);
+#if NACPIPWRRES > 0
+	SIMPLEQ_INIT(&sc->sc_pwrresdevs);
+#endif /* NACPIPWRRES > 0 */
+
 
 #ifndef SMALL_KERNEL
 	sc->sc_note = malloc(sizeof(struct klist), M_DEVBUF, M_NOWAIT | M_ZERO);