drm/nouveau/disp: add dp aux xfer method

- preparation for GSP-RM

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Danilo Krummrich <me@dakr.org>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230919220442.202488-28-lyude@redhat.com

3 files changed, 38 insertions, 4 deletions

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
index 99fe7ef07a44..49fbb32f5022 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/dp.c
@@ -42,6 +42,19 @@
 #define AMPERE_IED_HACK(disp) ((disp)->engine.subdev.device->card_type >= GA100)
 
 static int
+nvkm_dp_aux_xfer(struct nvkm_outp *outp, u8 type, u32 addr, u8 *data, u8 *size)
+{
+	int ret = nvkm_i2c_aux_acquire(outp->dp.aux);
+
+	if (ret)
+		return ret;
+
+	ret = nvkm_i2c_aux_xfer(outp->dp.aux, false, type, addr, data, size);
+	nvkm_i2c_aux_release(outp->dp.aux);
+	return ret;
+}
+
+static int
 nvkm_dp_aux_pwr(struct nvkm_outp *outp, bool pu)
 {
 	outp->dp.enabled = pu;
@@ -823,6 +836,7 @@ nvkm_dp_func = {
 	.bl.get = nvkm_outp_bl_get,
 	.bl.set = nvkm_outp_bl_set,
 	.dp.aux_pwr = nvkm_dp_aux_pwr,
+	.dp.aux_xfer = nvkm_dp_aux_xfer,
 };
 
 int
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
index 513794a278a9..a2391b224ea4 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
@@ -107,6 +107,7 @@ struct nvkm_outp_func {
 
 	struct {
 		int (*aux_pwr)(struct nvkm_outp *, bool pu);
+		int (*aux_xfer)(struct nvkm_outp *, u8 type, u32 addr, u8 *data, u8 *size);
 	} dp;
 };
 
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
index 6ca364e953bd..cd92db9028a3 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
@@ -25,6 +25,8 @@
 #include "head.h"
 #include "ior.h"
 
+#include <subdev/i2c.h>
+
 #include <nvif/if0012.h>
 
 static int
@@ -69,6 +71,20 @@ nvkm_uoutp_mthd_acquire_dp(struct nvkm_outp *outp, u8 dpcd[DP_RECEIVER_CAP_SIZE]
 }
 
 static int
+nvkm_uoutp_mthd_dp_aux_xfer(struct nvkm_outp *outp, void *argv, u32 argc)
+{
+	union nvif_outp_dp_aux_xfer_args *args = argv;
+
+	if (argc != sizeof(args->v0) || args->v0.version != 0)
+		return -ENOSYS;
+	if (!outp->func->dp.aux_xfer)
+		return -EINVAL;
+
+	return outp->func->dp.aux_xfer(outp, args->v0.type, args->v0.addr,
+					     args->v0.data, &args->v0.size);
+}
+
+static int
 nvkm_uoutp_mthd_dp_aux_pwr(struct nvkm_outp *outp, void *argv, u32 argc)
 {
 	union nvif_outp_dp_aux_pwr_args *args = argv;
@@ -429,7 +445,7 @@ nvkm_uoutp_mthd_acquired(struct nvkm_outp *outp, u32 mthd, void *argv, u32 argc)
 }
 
 static int
-nvkm_uoutp_mthd_noacquire(struct nvkm_outp *outp, u32 mthd, void *argv, u32 argc)
+nvkm_uoutp_mthd_noacquire(struct nvkm_outp *outp, u32 mthd, void *argv, u32 argc, bool *invalid)
 {
 	switch (mthd) {
 	case NVIF_OUTP_V0_DETECT     : return nvkm_uoutp_mthd_detect     (outp, argv, argc);
@@ -440,11 +456,13 @@ nvkm_uoutp_mthd_noacquire(struct nvkm_outp *outp, u32 mthd, void *argv, u32 argc
 	case NVIF_OUTP_V0_BL_GET     : return nvkm_uoutp_mthd_bl_get     (outp, argv, argc);
 	case NVIF_OUTP_V0_BL_SET     : return nvkm_uoutp_mthd_bl_set     (outp, argv, argc);
 	case NVIF_OUTP_V0_DP_AUX_PWR : return nvkm_uoutp_mthd_dp_aux_pwr (outp, argv, argc);
+	case NVIF_OUTP_V0_DP_AUX_XFER: return nvkm_uoutp_mthd_dp_aux_xfer(outp, argv, argc);
 	default:
 		break;
 	}
 
-	return 1;
+	*invalid = true;
+	return 0;
 }
 
 static int
@@ -452,12 +470,13 @@ nvkm_uoutp_mthd(struct nvkm_object *object, u32 mthd, void *argv, u32 argc)
 {
 	struct nvkm_outp *outp = nvkm_uoutp(object);
 	struct nvkm_disp *disp = outp->disp;
+	bool invalid = false;
 	int ret;
 
 	mutex_lock(&disp->super.mutex);
 
-	ret = nvkm_uoutp_mthd_noacquire(outp, mthd, argv, argc);
-	if (ret <= 0)
+	ret = nvkm_uoutp_mthd_noacquire(outp, mthd, argv, argc, &invalid);
+	if (!invalid)
 		goto done;
 
 	if (outp->ior)