drm/print: add drm_debug_enabled()

Add helper to check if a drm debug category is enabled. Convert drm core
to use it. No functional changes.

v2: Move unlikely() to drm_debug_enabled() (Eric)

v3: Keep unlikely() when combined with other conditions (Eric)

Cc: Eric Engestrom <[e-mail]>
Acked-by: Alex Deucher <[e-mail]>
Reviewed-by: Eric Engestrom <[e-mail]>
Signed-off-by: Jani Nikula <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/drm_atomic_uapi.c

···
 	} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
 		ret = drm_atomic_nonblocking_commit(state);
 	} else {
-		if (unlikely(drm_debug & DRM_UT_STATE))
+		if (drm_debug_enabled(DRM_UT_STATE))
 			drm_atomic_print_state(state);
 
 		ret = drm_atomic_commit(state);

drivers/gpu/drm/drm_dp_mst_topology.c

···
 		}
 	}
 out:
-	if (unlikely(ret == -EIO && drm_debug & DRM_UT_DP)) {
+	if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) {
 		struct drm_printer p = drm_debug_printer(DBG_PREFIX);
 
 		drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
···
 	idx += tosend + 1;
 
 	ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx);
-	if (unlikely(ret && drm_debug & DRM_UT_DP)) {
+	if (unlikely(ret) && drm_debug_enabled(DRM_UT_DP)) {
 		struct drm_printer p = drm_debug_printer(DBG_PREFIX);
 
 		drm_printf(&p, "sideband msg failed to send\n");
···
 	mutex_lock(&mgr->qlock);
 	list_add_tail(&txmsg->next, &mgr->tx_msg_downq);
 
-	if (unlikely(drm_debug & DRM_UT_DP)) {
+	if (drm_debug_enabled(DRM_UT_DP)) {
 		struct drm_printer p = drm_debug_printer(DBG_PREFIX);
 
 		drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);

drivers/gpu/drm/drm_edid.c

···
 {
 	int i;
 
-	if (connector->bad_edid_counter++ && !(drm_debug & DRM_UT_KMS))
+	if (connector->bad_edid_counter++ && !drm_debug_enabled(DRM_UT_KMS))
 		return;
 
 	dev_warn(connector->dev->dev,

drivers/gpu/drm/drm_edid_load.c

···
 	u8 *edid;
 	int fwsize, builtin;
 	int i, valid_extensions = 0;
-	bool print_bad_edid = !connector->bad_edid_counter || (drm_debug & DRM_UT_KMS);
+	bool print_bad_edid = !connector->bad_edid_counter || drm_debug_enabled(DRM_UT_KMS);
 
 	builtin = match_string(generic_edid_name, GENERIC_EDIDS, name);
 	if (builtin >= 0) {

drivers/gpu/drm/drm_mipi_dbi.c

···
 	int i, ret;
 	u8 *dst;
 
-	if (drm_debug & DRM_UT_DRIVER)
+	if (drm_debug_enabled(DRM_UT_DRIVER))
 		pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
 			 __func__, dc, max_chunk);
 
···
 	max_chunk = dbi->tx_buf9_len;
 	dst16 = dbi->tx_buf9;
 
-	if (drm_debug & DRM_UT_DRIVER)
+	if (drm_debug_enabled(DRM_UT_DRIVER))
 		pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
 			 __func__, dc, max_chunk);
 

drivers/gpu/drm/drm_print.c

···
 	struct va_format vaf;
 	va_list args;
 
-	if (!(drm_debug & category))
+	if (!drm_debug_enabled(category))
 		return;
 
 	va_start(args, format);
···
 	struct va_format vaf;
 	va_list args;
 
-	if (!(drm_debug & category))
+	if (!drm_debug_enabled(category))
 		return;
 
 	va_start(args, format);

drivers/gpu/drm/drm_vblank.c

···
 	u64 vblank;
 	unsigned long flags;
 
-	WARN_ONCE(drm_debug & DRM_UT_VBL && !dev->driver->get_vblank_timestamp,
+	WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) && !dev->driver->get_vblank_timestamp,
 		  "This function requires support for accurate vblank timestamps.");
 
 	spin_lock_irqsave(&dev->vblank_time_lock, flags);
···
 	 */
 	*vblank_time = ktime_sub_ns(etime, delta_ns);
 
-	if ((drm_debug & DRM_UT_VBL) == 0)
+	if (!drm_debug_enabled(DRM_UT_VBL))
 		return true;
 
 	ts_etime = ktime_to_timespec64(etime);
···
 	assert_spin_locked(&dev->vblank_time_lock);
 
 	vblank = &dev->vblank[pipe];
-	WARN_ONCE((drm_debug & DRM_UT_VBL) && !vblank->framedur_ns,
+	WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) && !vblank->framedur_ns,
 		  "Cannot compute missed vblanks without frame duration\n");
 	framedur_ns = vblank->framedur_ns;
 

include/drm/drm_print.h

···
 #define DRM_UT_LEASE		0x80
 #define DRM_UT_DP		0x100
 
+static inline bool drm_debug_enabled(unsigned int category)
+{
+	return unlikely(drm_debug & category);
+}
+
 __printf(3, 4)
 void drm_dev_printk(const struct device *dev, const char *level,
 		    const char *format, ...);