Skip to content

Commit

Permalink
Support backlight device in virtio gpu
Browse files Browse the repository at this point in the history 
Enable virtio backlight function, it will expose sysfs node
/sys/class/backlight/virtio-gpu-backlight0 for guest user.

Test-done:
- iGPU VF + virtio-GPU;
- backlight setting through command

Tracked-On: OAM-117147
Signed-off-by: Xue, Bosheng <[email protected]>
  • Loading branch information
@bosheng1
bosheng1 committed Sep 3, 2024
1 parent 5aff8c2 commit 297a008
Show file tree
Hide file tree
Showing 6 changed files with 281 additions and 0 deletions.
1 change: 1 addition & 0 deletions drivers/gpu/drm/virtio/Kconfig
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@ config DRM_VIRTIO_GPU
select DRM_KMS_HELPER
select DRM_GEM_SHMEM_HELPER
select VIRTIO_DMA_SHARED_BUFFER
select BACKLIGHT_CLASS_DEVICE
help
This is the virtual GPU driver for virtio. It can be used with
QEMU based VMMs (like KVM or Xen).
Expand Down
1 change: 1 addition & 0 deletions drivers/gpu/drm/virtio/virtgpu_drv.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -163,6 +163,7 @@ static unsigned int features[] = {
VIRTIO_GPU_F_MODIFIER,
VIRTIO_GPU_F_SCALING,
VIRTIO_GPU_F_VBLANK,
VIRTIO_GPU_F_BACKLIGHT,
VIRTIO_GPU_F_ALLOW_P2P,
VIRTIO_GPU_F_MULTI_PLANE,
VIRTIO_GPU_F_ROTATION,
Expand Down
26 changes: 26 additions & 0 deletions drivers/gpu/drm/virtio/virtgpu_drv.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
#include <linux/virtio_gpu.h>
#include <linux/backlight.h>

#include <drm/drm_atomic.h>
#include <drm/drm_drv.h>
Expand Down Expand Up @@ -175,6 +176,7 @@ struct virtio_gpu_vbuffer {
struct list_head list;

uint32_t seqno;
struct completion notify;
};

#define VIRTIO_GPU_MAX_PLANES 6
Expand Down Expand Up @@ -232,12 +234,26 @@ struct virtio_gpu_vblank {
uint32_t buf[4];
};

#define MAX_BACKLIGHT_NUM 16
struct virtio_gpu_backlight {
struct virtio_gpu_device *vgdev;
struct backlight_device *bd;
uint32_t backlight_id;
int32_t brightness;
int32_t max_brightness;
int32_t power;
enum backlight_type type;
enum backlight_scale scale;
};

struct virtio_gpu_device {
struct drm_device *ddev;

struct virtio_device *vdev;

struct virtio_gpu_output outputs[VIRTIO_GPU_MAX_SCANOUTS];
struct virtio_gpu_backlight backlight[MAX_BACKLIGHT_NUM];
uint32_t num_backlight;
uint32_t num_scanouts;
uint32_t num_vblankq;
struct virtio_gpu_queue ctrlq;
Expand All @@ -263,6 +279,7 @@ struct virtio_gpu_device {
bool has_modifier;
bool has_scaling;
bool has_vblank;
bool has_backlight;
bool has_allow_p2p;
bool has_multi_plane;
bool has_rotation;
Expand Down Expand Up @@ -489,6 +506,15 @@ void virtio_gpu_cmd_set_scaling(struct virtio_gpu_device *vgdev,
void virtio_gpu_cmd_send_misc(struct virtio_gpu_device *vgdev, uint32_t scanout_id,
uint32_t plane_indx, struct virtio_gpu_cmd *cmdp, int cnt);

int virtio_gpu_cmd_backlight_update_status(struct virtio_gpu_device *vgdev,
uint32_t backlight_id);

int virtio_gpu_cmd_get_brightness(struct virtio_gpu_device *vgdev,
uint32_t backlight_id);

int virtio_gpu_cmd_backlight_query(struct virtio_gpu_device *vgdev,
uint32_t backlight_id);

/* virtgpu_display.c */
int virtio_gpu_modeset_init(struct virtio_gpu_device *vgdev);
void virtio_gpu_modeset_fini(struct virtio_gpu_device *vgdev);
Expand Down
75 changes: 75 additions & 0 deletions drivers/gpu/drm/virtio/virtgpu_kms.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -173,6 +173,65 @@ int virtio_gpu_find_vqs(struct virtio_gpu_device *vgdev)
return ret;
}

static int virtio_backlight_device_update_status(struct backlight_device *bd)
{
int ret = 0;
struct virtio_gpu_backlight *backlight = bl_get_data(bd);
backlight->power = bd->props.power;
backlight->brightness = bd->props.brightness;
ret = virtio_gpu_cmd_backlight_update_status(backlight->vgdev, backlight->backlight_id);
return ret;
}

static int virtio_backlight_device_get_brightness(struct backlight_device *bd)
{
int ret = 0;
struct virtio_gpu_backlight *backlight = bl_get_data(bd);
ret = virtio_gpu_cmd_get_brightness(backlight->vgdev, backlight->backlight_id);
return backlight->brightness;
}

static const struct backlight_ops virtio_backlight_device_ops = {
.update_status = virtio_backlight_device_update_status,
.get_brightness = virtio_backlight_device_get_brightness,
};

int virtio_backlight_device_register(struct virtio_gpu_device *vgdev, int index)
{
struct backlight_properties props;
char *name;
struct backlight_device *bd;
int ret = 0;
memset(&props, 0, sizeof(props));
if (index >= vgdev->num_backlight) {
return -EINVAL;
}
vgdev->backlight[index].vgdev = vgdev;
ret = virtio_gpu_cmd_backlight_query(vgdev, index);
if (ret) {
pr_err("fail to query backlight(%d) device config, ret:%d", index, ret);
return ret;
}

props.type = vgdev->backlight[index].type;
props.power = vgdev->backlight[index].power;
props.scale = vgdev->backlight[index].scale;
props.brightness = vgdev->backlight[index].brightness;
props.max_brightness = vgdev->backlight[index].max_brightness;
name = kasprintf(GFP_KERNEL, "virtio-gpu-backlight%d", index);
bd = devm_backlight_device_register(&vgdev->vdev->dev, name, &vgdev->vdev->dev,
&vgdev->backlight[index], &virtio_backlight_device_ops, &props);
if (IS_ERR(bd)) {
DRM_ERROR("failed to register backlight device\n");
kfree(name);
return PTR_ERR(bd);
}
vgdev->backlight[index].bd = bd;
DRM_INFO("backlight device:%s registered\n", name);
kfree(name);
return 0;
}

int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev)
{
struct virtio_gpu_device *vgdev;
Expand Down Expand Up @@ -253,6 +312,10 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev)
vgdev->has_modifier = true;
}
}
if (virtio_has_feature(vgdev->vdev, VIRTIO_GPU_F_BACKLIGHT)) {
vgdev->has_backlight = true;
}

if (virtio_get_shm_region(vgdev->vdev, &vgdev->host_visible_region,
VIRTIO_GPU_SHM_ID_HOST_VISIBLE)) {
if (!devm_request_mem_region(&vgdev->vdev->dev,
Expand Down Expand Up @@ -322,8 +385,20 @@ int virtio_gpu_init(struct virtio_device *vdev, struct drm_device *dev)
virtio_cread_le(vgdev->vdev, struct virtio_gpu_config,
num_capsets, &num_capsets);
DRM_INFO("number of cap sets: %d\n", num_capsets);
vgdev->num_backlight = 0;
if (vgdev->has_backlight) {
virtio_cread_le(vgdev->vdev, struct virtio_gpu_config,
num_backlight, &vgdev->num_backlight);
if (vgdev->num_backlight > MAX_BACKLIGHT_NUM)
vgdev->num_backlight = MAX_BACKLIGHT_NUM;
}
DRM_INFO("number of virtio backlight: %d\n", vgdev->num_backlight);

virtio_device_ready(vgdev->vdev);

for(i = 0; i < vgdev->num_backlight; i++) {
virtio_backlight_device_register(vgdev, i);
}

if (num_capsets)
virtio_gpu_get_capsets(vgdev, num_capsets);
Expand Down
129 changes: 129 additions & 0 deletions drivers/gpu/drm/virtio/virtgpu_vq.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1581,3 +1581,132 @@ void virtio_gpu_cmd_set_scaling(struct virtio_gpu_device *vgdev,

virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
}

int virtio_gpu_cmd_backlight_update_status(struct virtio_gpu_device *vgdev,
uint32_t backlight_id)
{
struct virtio_gpu_backlight_update_status *cmd_p;
struct virtio_gpu_vbuffer *vbuf;

if (backlight_id >= vgdev->num_backlight) {
return -EINVAL;
}
cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
memset(cmd_p, 0, sizeof(*cmd_p));
cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_BACKLIGHT_UPDATE_STATUS);
cmd_p->backlight_id = cpu_to_le32(backlight_id);
cmd_p->brightness = cpu_to_le32(vgdev->backlight[backlight_id].brightness);
cmd_p->power = cpu_to_le32(vgdev->backlight[backlight_id].power);

virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
virtio_gpu_notify(vgdev);
return 0;
}

static void virtio_gpu_cmd_get_backlightness_cb(struct virtio_gpu_device *vgdev,
struct virtio_gpu_vbuffer *vbuf)
{
struct virtio_gpu_get_brightness *cmd_p =
(struct virtio_gpu_get_brightness *)vbuf->buf;
struct virtio_gpu_resp_brightness *resp =
(struct virtio_gpu_resp_brightness *)vbuf->resp_buf;
int32_t brightness = le32_to_cpu(resp->brightness);
uint32_t backlight_id = cmd_p->backlight_id;
if (backlight_id < vgdev->num_backlight) {
vgdev->backlight[backlight_id].brightness = brightness;
}
complete(&vbuf->notify);
}

int virtio_gpu_cmd_get_brightness(struct virtio_gpu_device *vgdev,
uint32_t backlight_id)
{
struct virtio_gpu_get_brightness *cmd_p;
struct virtio_gpu_vbuffer *vbuf;
void *resp_buf;
int ret = 0;

if (backlight_id >= vgdev->num_backlight)
return -EINVAL;
resp_buf = kzalloc(sizeof(struct virtio_gpu_resp_brightness),
GFP_KERNEL);
if (!resp_buf)
return -ENOMEM;

cmd_p = virtio_gpu_alloc_cmd_resp
(vgdev, &virtio_gpu_cmd_get_backlightness_cb, &vbuf,
sizeof(*cmd_p), sizeof(struct virtio_gpu_resp_brightness),
resp_buf);
memset(cmd_p, 0, sizeof(*cmd_p));

init_completion(&vbuf->notify);
cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_BACKLIGHT_GET);
cmd_p->backlight_id = backlight_id;
virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
virtio_gpu_notify(vgdev);
ret = wait_for_completion_interruptible_timeout(&vbuf->notify, 100*HZ);
if (ret <= 0)
return -ETIME;
return 0;
}

static void virtio_gpu_cmd_get_backlight_info_cb(struct virtio_gpu_device *vgdev,
struct virtio_gpu_vbuffer *vbuf)
{
struct virtio_gpu_get_backlight_info *cmd_p =
(struct virtio_gpu_get_backlight_info *)vbuf->buf;
struct virtio_gpu_resp_backlight_info *resp =
(struct virtio_gpu_resp_backlight_info *)vbuf->resp_buf;
int32_t brightness = le32_to_cpu(resp->brightness);
int32_t max_brightness = le32_to_cpu(resp->max_brightness);
int32_t power = le32_to_cpu(resp->power);
int32_t type = le32_to_cpu(resp->type);
int32_t scale = le32_to_cpu(resp->scale);
uint32_t backlight_id = cmd_p->backlight_id;
if (backlight_id < vgdev->num_backlight) {
vgdev->backlight[backlight_id].brightness = brightness;
vgdev->backlight[backlight_id].max_brightness = max_brightness;
vgdev->backlight[backlight_id].power = power;
if (type > 0 && type < BACKLIGHT_TYPE_MAX)
vgdev->backlight[backlight_id].type = type;
else
vgdev->backlight[backlight_id].type = BACKLIGHT_RAW;
if (scale >= BACKLIGHT_SCALE_UNKNOWN && scale <= BACKLIGHT_SCALE_NON_LINEAR)
vgdev->backlight[backlight_id].scale = scale;
else
vgdev->backlight[backlight_id].scale = BACKLIGHT_SCALE_UNKNOWN;
}
complete(&vbuf->notify);
}

int virtio_gpu_cmd_backlight_query(struct virtio_gpu_device *vgdev,
uint32_t backlight_id)
{
struct virtio_gpu_get_backlight_info *cmd_p;
struct virtio_gpu_vbuffer *vbuf;
void *resp_buf;
int ret = 0;

if (backlight_id >= vgdev->num_backlight)
return -EINVAL;
resp_buf = kzalloc(sizeof(struct virtio_gpu_resp_backlight_info),
GFP_KERNEL);
if (!resp_buf)
return -ENOMEM;

cmd_p = virtio_gpu_alloc_cmd_resp
(vgdev, &virtio_gpu_cmd_get_backlight_info_cb, &vbuf,
sizeof(*cmd_p), sizeof(struct virtio_gpu_resp_backlight_info),
resp_buf);
init_completion(&vbuf->notify);
memset(cmd_p, 0, sizeof(*cmd_p));

cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_BACKLIGHT_QUERY);
cmd_p->backlight_id = backlight_id;
virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
virtio_gpu_notify(vgdev);
ret = wait_for_completion_interruptible_timeout(&vbuf->notify, 100*HZ);
if (ret <= 0)
return -ETIME;
return 0;
}
49 changes: 49 additions & 0 deletions include/uapi/linux/virtio_gpu.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -75,6 +75,8 @@

#define VIRTIO_GPU_F_VBLANK 7

#define VIRTIO_GPU_F_BACKLIGHT 8

#define VIRTIO_GPU_F_ALLOW_P2P 31

/*
Expand Down Expand Up @@ -141,6 +143,11 @@ enum virtio_gpu_ctrl_type {
VIRTIO_GPU_CMD_UPDATE_CURSOR = 0x0300,
VIRTIO_GPU_CMD_MOVE_CURSOR,

/* backlight cmd */
VIRTIO_GPU_CMD_BACKLIGHT_UPDATE_STATUS = 0x0400,
VIRTIO_GPU_CMD_BACKLIGHT_GET,
VIRTIO_GPU_CMD_BACKLIGHT_QUERY,

/* success responses */
VIRTIO_GPU_RESP_OK_NODATA = 0x1100,
VIRTIO_GPU_RESP_OK_DISPLAY_INFO,
Expand All @@ -149,6 +156,8 @@ enum virtio_gpu_ctrl_type {
VIRTIO_GPU_RESP_OK_EDID,
VIRTIO_GPU_RESP_OK_RESOURCE_UUID,
VIRTIO_GPU_RESP_OK_MAP_INFO,
VIRTIO_GPU_RESP_OK_BACKLIGHT_GET,
VIRTIO_GPU_RESP_OK_BACKLIGHT,

/* error responses */
VIRTIO_GPU_RESP_ERR_UNSPEC = 0x1200,
Expand Down Expand Up @@ -300,6 +309,45 @@ struct virtio_gpu_set_scaling {
__le32 padding;
};

/* VIRTIO_GPU_CMD_BACKLIGHT_UPDATE_STATUS */
struct virtio_gpu_backlight_update_status {
struct virtio_gpu_ctrl_hdr hdr;
__le32 backlight_id;
__le32 brightness;
__le32 power;
__le32 padding;
};

/* VIRTIO_GPU_CMD_BACKLIGHT_GET */
struct virtio_gpu_get_brightness {
struct virtio_gpu_ctrl_hdr hdr;
__le32 backlight_id;
__le32 padding;
};

struct virtio_gpu_resp_brightness {
struct virtio_gpu_ctrl_hdr hdr;
__le32 brightness;
__le32 padding;
};

/* VIRTIO_GPU_CMD_BACKLIGHT_QUERY */
struct virtio_gpu_get_backlight_info {
struct virtio_gpu_ctrl_hdr hdr;
__le32 backlight_id;
__le32 padding;
};

struct virtio_gpu_resp_backlight_info {
struct virtio_gpu_ctrl_hdr hdr;
__le32 brightness;
__le32 max_brightness;
__le32 power;
__le32 type;
__le32 scale;
__le32 padding;
};

/* VIRTIO_GPU_CMD_TRANSFER_TO_HOST_2D: simple transfer to_host */
struct virtio_gpu_transfer_to_host_2d {
struct virtio_gpu_ctrl_hdr hdr;
Expand Down Expand Up @@ -487,6 +535,7 @@ struct virtio_gpu_config {
__le32 num_scanouts;
__le32 num_capsets;
__le32 num_pipe;
__le32 num_backlight;
};

/* simple formats for fbcon/X use */
Expand Down

0 comments on commit 297a008

Please sign in to comment.