[PATCH 2/4] drm/nouveau/acpi: return supported DSM functions

[Peter Wu]

Return the set of supported functions to the caller. No functional
changes.

Signed-off-by: Peter Wu <peter at lekensteyn.nl>
---
 drivers/gpu/drm/nouveau/nouveau_acpi.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_acpi.c 
b/drivers/gpu/drm/nouveau/nouveau_acpi.c
index 45fa9b2..71d5e6a 100644
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c
+++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c
@@ -107,7 +107,7 @@ static int nouveau_optimus_dsm(acpi_handle handle, int 
func, int arg, uint32_t *
  * requirements on the fourth parameter, so a private implementation
  * instead of using acpi_check_dsm().
  */
-static int nouveau_check_optimus_dsm(acpi_handle handle)
+static int nouveau_dsm_get_optimus_functions(acpi_handle handle)
 {
        int result;

@@ -122,7 +122,9 @@ static int nouveau_check_optimus_dsm(acpi_handle handle)
         * 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);
+       if (result & 1 && result & (1 << NOUVEAU_DSM_OPTIMUS_CAPS))
+               return result;
+       return 0;
 }

 static int nouveau_dsm(acpi_handle handle, int func, int arg)
@@ -214,7 +216,7 @@ static void nouveau_dsm_pci_probe(struct pci_dev *pdev, 
bool *has_mux,
 {
        acpi_handle dhandle;
        bool supports_mux;
-       bool supports_opt;
+       int optimus_funcs;

        dhandle = ACPI_HANDLE(&pdev->dev);
        if (!dhandle)
@@ -225,17 +227,17 @@ static void nouveau_dsm_pci_probe(struct pci_dev *pdev, 
bool *has_mux,

        supports_mux = acpi_check_dsm(dhandle, nouveau_dsm_muid, 0x00000102,
                                      1 << NOUVEAU_DSM_POWER);
-       supports_opt = nouveau_check_optimus_dsm(dhandle);
+       optimus_funcs = nouveau_dsm_get_optimus_functions(dhandle);

        /* Does not look like a Nvidia device. */
-       if (!supports_mux && !supports_opt)
+       if (!supports_mux && !optimus_funcs)
                return;

        nouveau_dsm_priv.dhandle = dhandle;
        *has_mux = supports_mux;
-       *has_opt = supports_opt;
+       *has_opt = !!optimus_funcs;

-       if (supports_opt) {
+       if (optimus_funcs) {
                uint32_t result;
                nouveau_optimus_dsm(dhandle, NOUVEAU_DSM_OPTIMUS_CAPS, 0,
                                    &result);
-- 
2.8.2