1 files changed, 78 insertions, 100 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index 95c740454049..83face3f608f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -1,15 +1,10 @@
 #include <linux/pci.h>
 #include <linux/acpi.h>
 #include <linux/slab.h>
-#include <acpi/acpi_drivers.h>
-#include <acpi/acpi_bus.h>
-#include <acpi/video.h>
-#include <acpi/acpi.h>
 #include <linux/mxm-wmi.h>
-
 #include <linux/vga_switcheroo.h>
-
 #include <drm/drm_edid.h>
+#include <acpi/video.h>
 
 #include "nouveau_drm.h"
 #include "nouveau_acpi.h"
@@ -51,6 +46,7 @@ static struct nouveau_dsm_priv {
 	bool dsm_detected;
 	bool optimus_detected;
 	acpi_handle dhandle;
+	acpi_handle other_handle;
 	acpi_handle rom_handle;
 } nouveau_dsm_priv;
 
@@ -65,6 +61,7 @@ bool nouveau_is_v1_dsm(void) {
 #define NOUVEAU_DSM_HAS_MUX 0x1
 #define NOUVEAU_DSM_HAS_OPT 0x2
 
+#ifdef CONFIG_VGA_SWITCHEROO
 static const char nouveau_dsm_muid[] = {
 	0xA0, 0xA0, 0x95, 0x9D, 0x60, 0x00, 0x48, 0x4D,
 	0xB3, 0x4D, 0x7E, 0x5F, 0xEA, 0x12, 0x9F, 0xD4,
@@ -77,124 +74,89 @@ static const char nouveau_op_dsm_muid[] = {
 
 static int nouveau_optimus_dsm(acpi_handle handle, int func, int arg, uint32_t *result)
 {
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	struct acpi_object_list input;
-	union acpi_object params[4];
+	int i;
 	union acpi_object *obj;
-	int i, err;
 	char args_buff[4];
+	union acpi_object argv4 = {
+		.buffer.type = ACPI_TYPE_BUFFER,
+		.buffer.length = 4,
+		.buffer.pointer = args_buff
+	};
 
-	input.count = 4;
-	input.pointer = params;
-	params[0].type = ACPI_TYPE_BUFFER;
-	params[0].buffer.length = sizeof(nouveau_op_dsm_muid);
-	params[0].buffer.pointer = (char *)nouveau_op_dsm_muid;
-	params[1].type = ACPI_TYPE_INTEGER;
-	params[1].integer.value = 0x00000100;
-	params[2].type = ACPI_TYPE_INTEGER;
-	params[2].integer.value = func;
-	params[3].type = ACPI_TYPE_BUFFER;
-	params[3].buffer.length = 4;
 	/* ACPI is little endian, AABBCCDD becomes {DD,CC,BB,AA} */
 	for (i = 0; i < 4; i++)
 		args_buff[i] = (arg >> i * 8) & 0xFF;
-	params[3].buffer.pointer = args_buff;
-
-	err = acpi_evaluate_object(handle, "_DSM", &input, &output);
-	if (err) {
-		printk(KERN_INFO "failed to evaluate _DSM: %d\n", err);
-		return err;
-	}
-
-	obj = (union acpi_object *)output.pointer;
-
-	if (obj->type == ACPI_TYPE_INTEGER)
-		if (obj->integer.value == 0x80000002) {
-			return -ENODEV;
-		}
 
-	if (obj->type == ACPI_TYPE_BUFFER) {
-		if (obj->buffer.length == 4 && result) {
-			*result = 0;
+	*result = 0;
+	obj = acpi_evaluate_dsm_typed(handle, nouveau_op_dsm_muid, 0x00000100,
+				      func, &argv4, ACPI_TYPE_BUFFER);
+	if (!obj) {
+		acpi_handle_info(handle, "failed to evaluate _DSM\n");
+		return AE_ERROR;
+	} else {
+		if (obj->buffer.length == 4) {
 			*result |= obj->buffer.pointer[0];
 			*result |= (obj->buffer.pointer[1] << 8);
 			*result |= (obj->buffer.pointer[2] << 16);
 			*result |= (obj->buffer.pointer[3] << 24);
 		}
+		ACPI_FREE(obj);
 	}
 
-	kfree(output.pointer);
 	return 0;
 }
 
-static int nouveau_dsm(acpi_handle handle, int func, int arg, uint32_t *result)
+/*
+ * On some platforms, _DSM(nouveau_op_dsm_muid, func0) has special
+ * requirements on the fourth parameter, so a private implementation
+ * instead of using acpi_check_dsm().
+ */
+static int nouveau_check_optimus_dsm(acpi_handle handle)
 {
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	struct acpi_object_list input;
-	union acpi_object params[4];
-	union acpi_object *obj;
-	int err;
-
-	input.count = 4;
-	input.pointer = params;
-	params[0].type = ACPI_TYPE_BUFFER;
-	params[0].buffer.length = sizeof(nouveau_dsm_muid);
-	params[0].buffer.pointer = (char *)nouveau_dsm_muid;
-	params[1].type = ACPI_TYPE_INTEGER;
-	params[1].integer.value = 0x00000102;
-	params[2].type = ACPI_TYPE_INTEGER;
-	params[2].integer.value = func;
-	params[3].type = ACPI_TYPE_INTEGER;
-	params[3].integer.value = arg;
-
-	err = acpi_evaluate_object(handle, "_DSM", &input, &output);
-	if (err) {
-		printk(KERN_INFO "failed to evaluate _DSM: %d\n", err);
-		return err;
-	}
-
-	obj = (union acpi_object *)output.pointer;
+	int result;
 
-	if (obj->type == ACPI_TYPE_INTEGER)
-		if (obj->integer.value == 0x80000002)
-			return -ENODEV;
-
-	if (obj->type == ACPI_TYPE_BUFFER) {
-		if (obj->buffer.length == 4 && result) {
-			*result = 0;
-			*result |= obj->buffer.pointer[0];
-			*result |= (obj->buffer.pointer[1] << 8);
-			*result |= (obj->buffer.pointer[2] << 16);
-			*result |= (obj->buffer.pointer[3] << 24);
-		}
-	}
+	/*
+	 * Function 0 returns a Buffer containing available functions.
+	 * The args parameter is ignored for function 0, so just put 0 in it
+	 */
+	if (nouveau_optimus_dsm(handle, 0, 0, &result))
+		return 0;
 
-	kfree(output.pointer);
-	return 0;
+	/*
+	 * ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported.
+	 * If the n-th bit is enabled, function n is supported
+	 */
+	return result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS);
 }
 
-/* Returns 1 if a DSM function is usable and 0 otherwise */
-static int nouveau_test_dsm(acpi_handle test_handle,
-	int (*dsm_func)(acpi_handle, int, int, uint32_t *),
-	int sfnc)
+static int nouveau_dsm(acpi_handle handle, int func, int arg)
 {
-	u32 result = 0;
-
-	/* Function 0 returns a Buffer containing available functions. The args
-	 * parameter is ignored for function 0, so just put 0 in it */
-	if (dsm_func(test_handle, 0, 0, &result))
-		return 0;
+	int ret = 0;
+	union acpi_object *obj;
+	union acpi_object argv4 = {
+		.integer.type = ACPI_TYPE_INTEGER,
+		.integer.value = arg,
+	};
+
+	obj = acpi_evaluate_dsm_typed(handle, nouveau_dsm_muid, 0x00000102,
+				      func, &argv4, ACPI_TYPE_INTEGER);
+	if (!obj) {
+		acpi_handle_info(handle, "failed to evaluate _DSM\n");
+		return AE_ERROR;
+	} else {
+		if (obj->integer.value == 0x80000002)
+			ret = -ENODEV;
+		ACPI_FREE(obj);
+	}
 
-	/* ACPI Spec v4 9.14.1: if bit 0 is zero, no function is supported. If
-	 * the n-th bit is enabled, function n is supported */
-	return result & 1 && result & (1 << sfnc);
+	return ret;
 }
 
 static int nouveau_dsm_switch_mux(acpi_handle handle, int mux_id)
 {
 	mxm_wmi_call_mxmx(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
 	mxm_wmi_call_mxds(mux_id == NOUVEAU_DSM_LED_STAMINA ? MXM_MXDS_ADAPTER_IGD : MXM_MXDS_ADAPTER_0);
-	return nouveau_dsm(handle, NOUVEAU_DSM_LED, mux_id, NULL);
+	return nouveau_dsm(handle, NOUVEAU_DSM_LED, mux_id);
 }
 
 static int nouveau_dsm_set_discrete_state(acpi_handle handle, enum vga_switcheroo_state state)
@@ -204,7 +166,7 @@ static int nouveau_dsm_set_discrete_state(acpi_handle handle, enum vga_switchero
 		arg = NOUVEAU_DSM_POWER_SPEED;
 	else
 		arg = NOUVEAU_DSM_POWER_STAMINA;
-	nouveau_dsm(handle, NOUVEAU_DSM_POWER, arg, NULL);
+	nouveau_dsm(handle, NOUVEAU_DSM_POWER, arg);
 	return 0;
 }
 
@@ -260,14 +222,15 @@ static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
 	if (!dhandle)
 		return false;
 
-	if (!acpi_has_method(dhandle, "_DSM"))
+	if (!acpi_has_method(dhandle, "_DSM")) {
+		nouveau_dsm_priv.other_handle = dhandle;
 		return false;
-
-	if (nouveau_test_dsm(dhandle, nouveau_dsm, NOUVEAU_DSM_POWER))
+	}
+	if (acpi_check_dsm(dhandle, nouveau_dsm_muid, 0x00000102,
+			   1 << NOUVEAU_DSM_POWER))
 		retval |= NOUVEAU_DSM_HAS_MUX;
 
-	if (nouveau_test_dsm(dhandle, nouveau_optimus_dsm,
-		NOUVEAU_DSM_OPTIMUS_CAPS))
+	if (nouveau_check_optimus_dsm(dhandle))
 		retval |= NOUVEAU_DSM_HAS_OPT;
 
 	if (retval & NOUVEAU_DSM_HAS_OPT) {
@@ -338,6 +301,16 @@ static bool nouveau_dsm_detect(void)
 		printk(KERN_INFO "VGA switcheroo: detected DSM switching method %s handle\n",
 			acpi_method_name);
 		nouveau_dsm_priv.dsm_detected = true;
+		/*
+		 * On some systems hotplug events are generated for the device
+		 * being switched off when _DSM is executed.  They cause ACPI
+		 * hotplug to trigger and attempt to remove the device from
+		 * the system, which causes it to break down.  Prevent that from
+		 * happening by setting the no_hotplug flag for the involved
+		 * ACPI device objects.
+		 */
+		acpi_bus_no_hotplug(nouveau_dsm_priv.dhandle);
+		acpi_bus_no_hotplug(nouveau_dsm_priv.other_handle);
 		ret = true;
 	}
 
@@ -376,6 +349,11 @@ void nouveau_unregister_dsm_handler(void)
 	if (nouveau_dsm_priv.optimus_detected || nouveau_dsm_priv.dsm_detected)
 		vga_switcheroo_unregister_handler();
 }
+#else
+void nouveau_register_dsm_handler(void) {}
+void nouveau_unregister_dsm_handler(void) {}
+void nouveau_switcheroo_optimus_dsm(void) {}
+#endif
 
 /* retrieve the ROM in 4k blocks */
 static int nouveau_rom_call(acpi_handle rom_handle, uint8_t *bios,