ACPI / nouveau: replace open-coded _DSM code with helper functions

Use helper functions to simplify _DSM related code in nouveau driver.
After analyzing the ACPI _DSM related code, I changed nouveau_optimus_dsm()
to expect a buffer and nouveau_dsm() to expect an integer only.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/gpu/drm/nouveau/core/subdev/mxm/base.c b/drivers/gpu/drm/nouveau/core/subdev/mxm/base.c
index 1291204..13c5af8 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/subdev/mxm/base.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mxm/base.c
@@ -87,55 +87,39 @@ mxm_shadow_dsm(struct nouveau_mxm *mxm, u8 version)
                0xB8, 0x9C, 0x79, 0xB6, 0x2F, 0xD5, 0x56, 0x65
        };
        u32 mxms_args[] = { 0x00000000 };
-       union acpi_object args[4] = {
-               /* _DSM MUID */
-               { .buffer.type = 3,
-                 .buffer.length = sizeof(muid),
-                 .buffer.pointer = muid,
-               },
-               /* spec says this can be zero to mean "highest revision", but
-                * of course there's at least one bios out there which fails
-                * unless you pass in exactly the version it supports..
-                */
-               { .integer.type = ACPI_TYPE_INTEGER,
-                 .integer.value = (version & 0xf0) << 4 | (version & 0x0f),
-               },
-               /* MXMS function */
-               { .integer.type = ACPI_TYPE_INTEGER,
-                 .integer.value = 0x00000010,
-               },
-               /* Pointer to MXMS arguments */
-               { .buffer.type = ACPI_TYPE_BUFFER,
-                 .buffer.length = sizeof(mxms_args),
-                 .buffer.pointer = (char *)mxms_args,
-               },
+       union acpi_object argv4 = {
+               .buffer.type = ACPI_TYPE_BUFFER,
+               .buffer.length = sizeof(mxms_args),
+               .buffer.pointer = (char *)mxms_args,
        };
-       struct acpi_object_list list = { ARRAY_SIZE(args), args };
-       struct acpi_buffer retn = { ACPI_ALLOCATE_BUFFER, NULL };
        union acpi_object *obj;
        acpi_handle handle;
-       int ret;
+       int rev;
 
        handle = ACPI_HANDLE(&device->pdev->dev);
        if (!handle)
                return false;
 
-       ret = acpi_evaluate_object(handle, "_DSM", &list, &retn);
-       if (ret) {
-               nv_debug(mxm, "DSM MXMS failed: %d\n", ret);
+       /*
+        * spec says this can be zero to mean "highest revision", but
+        * of course there's at least one bios out there which fails
+        * unless you pass in exactly the version it supports..
+        */
+       rev = (version & 0xf0) << 4 | (version & 0x0f);
+       obj = acpi_evaluate_dsm(handle, muid, rev, 0x00000010, &argv4);
+       if (!obj) {
+               nv_debug(mxm, "DSM MXMS failed\n");
                return false;
        }
 
-       obj = retn.pointer;
        if (obj->type == ACPI_TYPE_BUFFER) {
                mxm->mxms = kmemdup(obj->buffer.pointer,
                                         obj->buffer.length, GFP_KERNEL);
-       } else
-       if (obj->type == ACPI_TYPE_INTEGER) {
+       } else if (obj->type == ACPI_TYPE_INTEGER) {
                nv_debug(mxm, "DSM MXMS returned 0x%llx\n", obj->integer.value);
        }
 
-       kfree(obj);
+       ACPI_FREE(obj);
        return mxm->mxms != NULL;
 }
 #endif

diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index 3f721e3..879a8b4 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -78,127 +78,66 @@ 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) {
-                       kfree(output.pointer);
-                       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)
+static int nouveau_dsm(acpi_handle handle, int func, int arg)
 {
-       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-       struct acpi_object_list input;
-       union acpi_object params[4];
+       int ret = 0;
        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;
-
-       if (obj->type == ACPI_TYPE_INTEGER)
-               if (obj->integer.value == 0x80000002) {
-                       kfree(output.pointer);
-                       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);
-               }
+       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);
        }
 
-       kfree(output.pointer);
-       return 0;
-}
-
-/* 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)
-{
-       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;
-
-       /* 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)
@@ -208,7 +147,7 @@ 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;
 }
 
@@ -268,11 +207,12 @@ static int nouveau_dsm_pci_probe(struct pci_dev *pdev)
                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 (acpi_check_dsm(dhandle, nouveau_op_dsm_muid, 0x00000100,
+                          1 << NOUVEAU_DSM_OPTIMUS_CAPS))
                retval |= NOUVEAU_DSM_HAS_OPT;
 
        if (retval & NOUVEAU_DSM_HAS_OPT) {