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-rw-r--r--drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c11
-rw-r--r--drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c5
-rw-r--r--drivers/gpu/drm/amd/amdgpu/vce_v2_0.c2
-rw-r--r--drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c8
-rw-r--r--drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c17
-rw-r--r--drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c1
-rw-r--r--drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c64
-rw-r--r--drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c7
-rw-r--r--drivers/gpu/drm/amd/display/dc/core/dc_resource.c7
-rw-r--r--drivers/gpu/drm/amd/display/dc/dce60/dce60_timing_generator.c1
-rw-r--r--drivers/gpu/drm/display/drm_dp_mst_topology.c40
-rw-r--r--drivers/gpu/drm/drm_atomic_uapi.c4
-rw-r--r--drivers/gpu/drm/drm_connector.c4
-rw-r--r--drivers/gpu/drm/drm_panic_qr.rs16
-rw-r--r--drivers/gpu/drm/gma500/mid_bios.c5
15 files changed, 136 insertions, 56 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 95a05b03f799..c0ddbe7d6f0b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2555,7 +2555,6 @@ static int amdgpu_pmops_freeze(struct device *dev)
int r;
r = amdgpu_device_suspend(drm_dev, true);
- adev->in_s4 = false;
if (r)
return r;
@@ -2567,8 +2566,13 @@ static int amdgpu_pmops_freeze(struct device *dev)
static int amdgpu_pmops_thaw(struct device *dev)
{
struct drm_device *drm_dev = dev_get_drvdata(dev);
+ struct amdgpu_device *adev = drm_to_adev(drm_dev);
+ int r;
- return amdgpu_device_resume(drm_dev, true);
+ r = amdgpu_device_resume(drm_dev, true);
+ adev->in_s4 = false;
+
+ return r;
}
static int amdgpu_pmops_poweroff(struct device *dev)
@@ -2581,6 +2585,9 @@ static int amdgpu_pmops_poweroff(struct device *dev)
static int amdgpu_pmops_restore(struct device *dev)
{
struct drm_device *drm_dev = dev_get_drvdata(dev);
+ struct amdgpu_device *adev = drm_to_adev(drm_dev);
+
+ adev->in_s4 = false;
return amdgpu_device_resume(drm_dev, true);
}
diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
index b749f1c3f6a9..0fb88e6d5d54 100644
--- a/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/gmc_v12_0.c
@@ -528,8 +528,9 @@ static void gmc_v12_0_get_vm_pte(struct amdgpu_device *adev,
bo_adev = amdgpu_ttm_adev(bo->tbo.bdev);
coherent = bo->flags & AMDGPU_GEM_CREATE_COHERENT;
- is_system = (bo->tbo.resource->mem_type == TTM_PL_TT) ||
- (bo->tbo.resource->mem_type == AMDGPU_PL_PREEMPT);
+ is_system = bo->tbo.resource &&
+ (bo->tbo.resource->mem_type == TTM_PL_TT ||
+ bo->tbo.resource->mem_type == AMDGPU_PL_PREEMPT);
if (bo && bo->flags & AMDGPU_GEM_CREATE_GFX12_DCC)
*flags |= AMDGPU_PTE_DCC;
diff --git a/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c b/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
index c633b7ff2943..09fd6ef99b3d 100644
--- a/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vce_v2_0.c
@@ -284,7 +284,7 @@ static int vce_v2_0_stop(struct amdgpu_device *adev)
return 0;
}
- ip_block = amdgpu_device_ip_get_ip_block(adev, AMD_IP_BLOCK_TYPE_VCN);
+ ip_block = amdgpu_device_ip_get_ip_block(adev, AMD_IP_BLOCK_TYPE_VCE);
if (!ip_block)
return -EINVAL;
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
index d4593374e7a1..34c2c42c0f95 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
@@ -1230,11 +1230,13 @@ static int evict_process_queues_cpsch(struct device_queue_manager *dqm,
decrement_queue_count(dqm, qpd, q);
if (dqm->dev->kfd->shared_resources.enable_mes) {
- retval = remove_queue_mes(dqm, q, qpd);
- if (retval) {
+ int err;
+
+ err = remove_queue_mes(dqm, q, qpd);
+ if (err) {
dev_err(dev, "Failed to evict queue %d\n",
q->properties.queue_id);
- goto out;
+ retval = err;
}
}
}
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 9d9645a2d18e..74ad0d1240fe 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -245,6 +245,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
static void handle_hpd_irq_helper(struct amdgpu_dm_connector *aconnector);
static void handle_hpd_rx_irq(void *param);
+static void amdgpu_dm_backlight_set_level(struct amdgpu_display_manager *dm,
+ int bl_idx,
+ u32 user_brightness);
+
static bool
is_timing_unchanged_for_freesync(struct drm_crtc_state *old_crtc_state,
struct drm_crtc_state *new_crtc_state);
@@ -3371,8 +3375,19 @@ static int dm_resume(struct amdgpu_ip_block *ip_block)
mutex_unlock(&dm->dc_lock);
+ /* set the backlight after a reset */
+ for (i = 0; i < dm->num_of_edps; i++) {
+ if (dm->backlight_dev[i])
+ amdgpu_dm_backlight_set_level(dm, i, dm->brightness[i]);
+ }
+
return 0;
}
+
+ /* leave display off for S4 sequence */
+ if (adev->in_s4)
+ return 0;
+
/* Recreate dc_state - DC invalidates it when setting power state to S3. */
dc_state_release(dm_state->context);
dm_state->context = dc_state_create(dm->dc, NULL);
@@ -4906,6 +4921,7 @@ amdgpu_dm_register_backlight_device(struct amdgpu_dm_connector *aconnector)
dm->backlight_dev[aconnector->bl_idx] =
backlight_device_register(bl_name, aconnector->base.kdev, dm,
&amdgpu_dm_backlight_ops, &props);
+ dm->brightness[aconnector->bl_idx] = props.brightness;
if (IS_ERR(dm->backlight_dev[aconnector->bl_idx])) {
DRM_ERROR("DM: Backlight registration failed!\n");
@@ -4973,7 +4989,6 @@ static void setup_backlight_device(struct amdgpu_display_manager *dm,
aconnector->bl_idx = bl_idx;
amdgpu_dm_update_backlight_caps(dm, bl_idx);
- dm->brightness[bl_idx] = AMDGPU_MAX_BL_LEVEL;
dm->backlight_link[bl_idx] = link;
dm->num_of_edps++;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
index e339c7a8d541..c0dc23244049 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c
@@ -455,6 +455,7 @@ void hdcp_destroy(struct kobject *kobj, struct hdcp_workqueue *hdcp_work)
for (i = 0; i < hdcp_work->max_link; i++) {
cancel_delayed_work_sync(&hdcp_work[i].callback_dwork);
cancel_delayed_work_sync(&hdcp_work[i].watchdog_timer_dwork);
+ cancel_delayed_work_sync(&hdcp_work[i].property_validate_dwork);
}
sysfs_remove_bin_file(kobj, &hdcp_work[0].attr);
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
index c4a7fd453e5f..a215234151ac 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c
@@ -894,8 +894,16 @@ void amdgpu_dm_hpd_init(struct amdgpu_device *adev)
struct drm_device *dev = adev_to_drm(adev);
struct drm_connector *connector;
struct drm_connector_list_iter iter;
+ int irq_type;
int i;
+ /* First, clear all hpd and hpdrx interrupts */
+ for (i = DC_IRQ_SOURCE_HPD1; i <= DC_IRQ_SOURCE_HPD6RX; i++) {
+ if (!dc_interrupt_set(adev->dm.dc, i, false))
+ drm_err(dev, "Failed to clear hpd(rx) source=%d on init\n",
+ i);
+ }
+
drm_connector_list_iter_begin(dev, &iter);
drm_for_each_connector_iter(connector, &iter) {
struct amdgpu_dm_connector *amdgpu_dm_connector;
@@ -908,10 +916,31 @@ void amdgpu_dm_hpd_init(struct amdgpu_device *adev)
dc_link = amdgpu_dm_connector->dc_link;
+ /*
+ * Get a base driver irq reference for hpd ints for the lifetime
+ * of dm. Note that only hpd interrupt types are registered with
+ * base driver; hpd_rx types aren't. IOW, amdgpu_irq_get/put on
+ * hpd_rx isn't available. DM currently controls hpd_rx
+ * explicitly with dc_interrupt_set()
+ */
if (dc_link->irq_source_hpd != DC_IRQ_SOURCE_INVALID) {
- dc_interrupt_set(adev->dm.dc,
- dc_link->irq_source_hpd,
- true);
+ irq_type = dc_link->irq_source_hpd - DC_IRQ_SOURCE_HPD1;
+ /*
+ * TODO: There's a mismatch between mode_info.num_hpd
+ * and what bios reports as the # of connectors with hpd
+ * sources. Since the # of hpd source types registered
+ * with base driver == mode_info.num_hpd, we have to
+ * fallback to dc_interrupt_set for the remaining types.
+ */
+ if (irq_type < adev->mode_info.num_hpd) {
+ if (amdgpu_irq_get(adev, &adev->hpd_irq, irq_type))
+ drm_err(dev, "DM_IRQ: Failed get HPD for source=%d)!\n",
+ dc_link->irq_source_hpd);
+ } else {
+ dc_interrupt_set(adev->dm.dc,
+ dc_link->irq_source_hpd,
+ true);
+ }
}
if (dc_link->irq_source_hpd_rx != DC_IRQ_SOURCE_INVALID) {
@@ -921,12 +950,6 @@ void amdgpu_dm_hpd_init(struct amdgpu_device *adev)
}
}
drm_connector_list_iter_end(&iter);
-
- /* Update reference counts for HPDs */
- for (i = DC_IRQ_SOURCE_HPD1; i <= adev->mode_info.num_hpd; i++) {
- if (amdgpu_irq_get(adev, &adev->hpd_irq, i - DC_IRQ_SOURCE_HPD1))
- drm_err(dev, "DM_IRQ: Failed get HPD for source=%d)!\n", i);
- }
}
/**
@@ -942,7 +965,7 @@ void amdgpu_dm_hpd_fini(struct amdgpu_device *adev)
struct drm_device *dev = adev_to_drm(adev);
struct drm_connector *connector;
struct drm_connector_list_iter iter;
- int i;
+ int irq_type;
drm_connector_list_iter_begin(dev, &iter);
drm_for_each_connector_iter(connector, &iter) {
@@ -956,9 +979,18 @@ void amdgpu_dm_hpd_fini(struct amdgpu_device *adev)
dc_link = amdgpu_dm_connector->dc_link;
if (dc_link->irq_source_hpd != DC_IRQ_SOURCE_INVALID) {
- dc_interrupt_set(adev->dm.dc,
- dc_link->irq_source_hpd,
- false);
+ irq_type = dc_link->irq_source_hpd - DC_IRQ_SOURCE_HPD1;
+
+ /* TODO: See same TODO in amdgpu_dm_hpd_init() */
+ if (irq_type < adev->mode_info.num_hpd) {
+ if (amdgpu_irq_put(adev, &adev->hpd_irq, irq_type))
+ drm_err(dev, "DM_IRQ: Failed put HPD for source=%d!\n",
+ dc_link->irq_source_hpd);
+ } else {
+ dc_interrupt_set(adev->dm.dc,
+ dc_link->irq_source_hpd,
+ false);
+ }
}
if (dc_link->irq_source_hpd_rx != DC_IRQ_SOURCE_INVALID) {
@@ -968,10 +1000,4 @@ void amdgpu_dm_hpd_fini(struct amdgpu_device *adev)
}
}
drm_connector_list_iter_end(&iter);
-
- /* Update reference counts for HPDs */
- for (i = DC_IRQ_SOURCE_HPD1; i <= adev->mode_info.num_hpd; i++) {
- if (amdgpu_irq_put(adev, &adev->hpd_irq, i - DC_IRQ_SOURCE_HPD1))
- drm_err(dev, "DM_IRQ: Failed put HPD for source=%d!\n", i);
- }
}
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
index 774cc3f4f3fd..92472109f84a 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
@@ -277,8 +277,11 @@ static int amdgpu_dm_plane_validate_dcc(struct amdgpu_device *adev,
if (!dcc->enable)
return 0;
- if (format >= SURFACE_PIXEL_FORMAT_VIDEO_BEGIN ||
- !dc->cap_funcs.get_dcc_compression_cap)
+ if (adev->family < AMDGPU_FAMILY_GC_12_0_0 &&
+ format >= SURFACE_PIXEL_FORMAT_VIDEO_BEGIN)
+ return -EINVAL;
+
+ if (!dc->cap_funcs.get_dcc_compression_cap)
return -EINVAL;
input.format = format;
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index a45037cb4cc0..298668e9729c 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -3389,10 +3389,13 @@ static int get_norm_pix_clk(const struct dc_crtc_timing *timing)
break;
case COLOR_DEPTH_121212:
normalized_pix_clk = (pix_clk * 36) / 24;
- break;
+ break;
+ case COLOR_DEPTH_141414:
+ normalized_pix_clk = (pix_clk * 42) / 24;
+ break;
case COLOR_DEPTH_161616:
normalized_pix_clk = (pix_clk * 48) / 24;
- break;
+ break;
default:
ASSERT(0);
break;
diff --git a/drivers/gpu/drm/amd/display/dc/dce60/dce60_timing_generator.c b/drivers/gpu/drm/amd/display/dc/dce60/dce60_timing_generator.c
index e5fb0e8333e4..e691a1cf3356 100644
--- a/drivers/gpu/drm/amd/display/dc/dce60/dce60_timing_generator.c
+++ b/drivers/gpu/drm/amd/display/dc/dce60/dce60_timing_generator.c
@@ -239,6 +239,7 @@ static const struct timing_generator_funcs dce60_tg_funcs = {
dce60_timing_generator_enable_advanced_request,
.configure_crc = dce60_configure_crc,
.get_crc = dce110_get_crc,
+ .is_two_pixels_per_container = dce110_is_two_pixels_per_container,
};
void dce60_timing_generator_construct(
diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 06c91c5b7f7c..6d09bef671da 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -4025,6 +4025,22 @@ out:
return 0;
}
+static bool primary_mstb_probing_is_done(struct drm_dp_mst_topology_mgr *mgr)
+{
+ bool probing_done = false;
+
+ mutex_lock(&mgr->lock);
+
+ if (mgr->mst_primary && drm_dp_mst_topology_try_get_mstb(mgr->mst_primary)) {
+ probing_done = mgr->mst_primary->link_address_sent;
+ drm_dp_mst_topology_put_mstb(mgr->mst_primary);
+ }
+
+ mutex_unlock(&mgr->lock);
+
+ return probing_done;
+}
+
static inline bool
drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_pending_up_req *up_req)
@@ -4055,8 +4071,12 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
/* TODO: Add missing handler for DP_RESOURCE_STATUS_NOTIFY events */
if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
- dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
- hotplug = true;
+ if (!primary_mstb_probing_is_done(mgr)) {
+ drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.\n");
+ } else {
+ dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
+ hotplug = true;
+ }
}
drm_dp_mst_topology_put_mstb(mstb);
@@ -4138,10 +4158,11 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
drm_dp_send_up_ack_reply(mgr, mst_primary, up_req->msg.req_type,
false);
+ drm_dp_mst_topology_put_mstb(mst_primary);
+
if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
const struct drm_dp_connection_status_notify *conn_stat =
&up_req->msg.u.conn_stat;
- bool handle_csn;
drm_dbg_kms(mgr->dev, "Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n",
conn_stat->port_number,
@@ -4150,16 +4171,6 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
conn_stat->message_capability_status,
conn_stat->input_port,
conn_stat->peer_device_type);
-
- mutex_lock(&mgr->probe_lock);
- handle_csn = mst_primary->link_address_sent;
- mutex_unlock(&mgr->probe_lock);
-
- if (!handle_csn) {
- drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.");
- kfree(up_req);
- goto out_put_primary;
- }
} else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
const struct drm_dp_resource_status_notify *res_stat =
&up_req->msg.u.resource_stat;
@@ -4174,9 +4185,6 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
list_add_tail(&up_req->next, &mgr->up_req_list);
mutex_unlock(&mgr->up_req_lock);
queue_work(system_long_wq, &mgr->up_req_work);
-
-out_put_primary:
- drm_dp_mst_topology_put_mstb(mst_primary);
out_clear_reply:
reset_msg_rx_state(&mgr->up_req_recv);
return ret;
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 370dc676e3aa..fd36b8fd54e9 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -956,6 +956,10 @@ int drm_atomic_connector_commit_dpms(struct drm_atomic_state *state,
if (mode != DRM_MODE_DPMS_ON)
mode = DRM_MODE_DPMS_OFF;
+
+ if (connector->dpms == mode)
+ goto out;
+
connector->dpms = mode;
crtc = connector->state->crtc;
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 5f24d6b41cc6..48b08c9611a7 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -1427,6 +1427,10 @@ EXPORT_SYMBOL(drm_hdmi_connector_get_output_format_name);
* callback. For atomic drivers the remapping to the "ACTIVE" property is
* implemented in the DRM core.
*
+ * On atomic drivers any DPMS setproperty ioctl where the value does not
+ * change is completely skipped, otherwise a full atomic commit will occur.
+ * On legacy drivers the exact behavior is driver specific.
+ *
* Note that this property cannot be set through the MODE_ATOMIC ioctl,
* userspace must use "ACTIVE" on the CRTC instead.
*
diff --git a/drivers/gpu/drm/drm_panic_qr.rs b/drivers/gpu/drm/drm_panic_qr.rs
index bcf248f69252..6903e2010cb9 100644
--- a/drivers/gpu/drm/drm_panic_qr.rs
+++ b/drivers/gpu/drm/drm_panic_qr.rs
@@ -545,7 +545,7 @@ impl EncodedMsg<'_> {
}
self.push(&mut offset, (MODE_STOP, 4));
- let pad_offset = (offset + 7) / 8;
+ let pad_offset = offset.div_ceil(8);
for i in pad_offset..self.version.max_data() {
self.data[i] = PADDING[(i & 1) ^ (pad_offset & 1)];
}
@@ -659,7 +659,7 @@ struct QrImage<'a> {
impl QrImage<'_> {
fn new<'a, 'b>(em: &'b EncodedMsg<'b>, qrdata: &'a mut [u8]) -> QrImage<'a> {
let width = em.version.width();
- let stride = (width + 7) / 8;
+ let stride = width.div_ceil(8);
let data = qrdata;
let mut qr_image = QrImage {
@@ -911,16 +911,16 @@ impl QrImage<'_> {
///
/// * `url`: The base URL of the QR code. It will be encoded as Binary segment.
/// * `data`: A pointer to the binary data, to be encoded. if URL is NULL, it
-/// will be encoded as binary segment, otherwise it will be encoded
-/// efficiently as a numeric segment, and appended to the URL.
+/// will be encoded as binary segment, otherwise it will be encoded
+/// efficiently as a numeric segment, and appended to the URL.
/// * `data_len`: Length of the data, that needs to be encoded, must be less
-/// than data_size.
+/// than data_size.
/// * `data_size`: Size of data buffer, it should be at least 4071 bytes to hold
-/// a V40 QR code. It will then be overwritten with the QR code image.
+/// a V40 QR code. It will then be overwritten with the QR code image.
/// * `tmp`: A temporary buffer that the QR code encoder will use, to write the
-/// segments and ECC.
+/// segments and ECC.
/// * `tmp_size`: Size of the temporary buffer, it must be at least 3706 bytes
-/// long for V40.
+/// long for V40.
///
/// # Safety
///
diff --git a/drivers/gpu/drm/gma500/mid_bios.c b/drivers/gpu/drm/gma500/mid_bios.c
index 7e76790c6a81..cba97d7db131 100644
--- a/drivers/gpu/drm/gma500/mid_bios.c
+++ b/drivers/gpu/drm/gma500/mid_bios.c
@@ -279,6 +279,11 @@ static void mid_get_vbt_data(struct drm_psb_private *dev_priv)
0, PCI_DEVFN(2, 0));
int ret = -1;
+ if (pci_gfx_root == NULL) {
+ WARN_ON(1);
+ return;
+ }
+
/* Get the address of the platform config vbt */
pci_read_config_dword(pci_gfx_root, 0xFC, &addr);
pci_dev_put(pci_gfx_root);