[Intel-gfx] [PATCH] drm/i915: Unifying debugfs return codes for unsupported features

[Michal Wajdeczko]

Instead of trying different seq_puts messages, lets use common
-ENODEV error code to indicate missing/unsupported feature.

Suggested-by: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
Cc: Sujaritha Sundaresan <sujaritha.sundaresan at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 47 ++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 2829447..5023acd 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1635,10 +1635,8 @@ static int i915_fbc_status(struct seq_file *m, void *unused)
 {
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
 
-	if (!HAS_FBC(dev_priv)) {
-		seq_puts(m, "FBC unsupported on this chipset\n");
-		return 0;
-	}
+	if (!HAS_FBC(dev_priv))
+		return -ENODEV;
 
 	intel_runtime_pm_get(dev_priv);
 	mutex_lock(&dev_priv->fbc.lock);
@@ -1714,10 +1712,8 @@ static int i915_ips_status(struct seq_file *m, void *unused)
 {
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
 
-	if (!HAS_IPS(dev_priv)) {
-		seq_puts(m, "not supported\n");
-		return 0;
-	}
+	if (!HAS_IPS(dev_priv))
+		return -ENODEV;
 
 	intel_runtime_pm_get(dev_priv);
 
@@ -1803,10 +1799,8 @@ static int i915_ring_freq_table(struct seq_file *m, void *unused)
 	int gpu_freq, ia_freq;
 	unsigned int max_gpu_freq, min_gpu_freq;
 
-	if (!HAS_LLC(dev_priv)) {
-		seq_puts(m, "unsupported on this chipset\n");
-		return 0;
-	}
+	if (!HAS_LLC(dev_priv))
+		return -ENODEV;
 
 	intel_runtime_pm_get(dev_priv);
 
@@ -2287,7 +2281,7 @@ static int i915_huc_load_status_info(struct seq_file *m, void *data)
 	struct drm_printer p;
 
 	if (!HAS_HUC_UCODE(dev_priv))
-		return 0;
+		return -ENODEV;
 
 	p = drm_seq_file_printer(m);
 	intel_uc_fw_dump(&dev_priv->huc.fw, &p);
@@ -2305,8 +2299,8 @@ static int i915_guc_load_status_info(struct seq_file *m, void *data)
 	struct drm_printer p;
 	u32 tmp, i;
 
-	if (!HAS_GUC_UCODE(dev_priv))
-		return 0;
+	if (!HAS_GUC(dev_priv))
+		return -ENODEV;
 
 	p = drm_seq_file_printer(m);
 	intel_uc_fw_dump(&dev_priv->guc.fw, &p);
@@ -2400,6 +2394,9 @@ static int i915_guc_info(struct seq_file *m, void *data)
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
 	const struct intel_guc *guc = &dev_priv->guc;
 
+	if (!HAS_GUC(dev_priv))
+		return -ENODEV;
+
 	if (!check_guc_submission(m))
 		return 0;
 
@@ -2428,6 +2425,9 @@ static int i915_guc_stage_pool(struct seq_file *m, void *data)
 	unsigned int tmp;
 	int index;
 
+	if (!HAS_GUC(dev_priv))
+		return -ENODEV;
+
 	if (!check_guc_submission(m))
 		return 0;
 
@@ -2482,6 +2482,9 @@ static int i915_guc_log_dump(struct seq_file *m, void *data)
 	u32 *log;
 	int i = 0;
 
+	if (!HAS_GUC(dev_priv))
+		return -ENODEV;
+
 	if (dump_load_err)
 		obj = dev_priv->guc.load_err_log;
 	else if (dev_priv->guc.log.vma)
@@ -2576,10 +2579,8 @@ static int i915_edp_psr_status(struct seq_file *m, void *data)
 	enum pipe pipe;
 	bool enabled = false;
 
-	if (!HAS_PSR(dev_priv)) {
-		seq_puts(m, "PSR not supported\n");
-		return 0;
-	}
+	if (!HAS_PSR(dev_priv))
+		return -ENODEV;
 
 	intel_runtime_pm_get(dev_priv);
 
@@ -2818,10 +2819,8 @@ static int i915_dmc_info(struct seq_file *m, void *unused)
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
 	struct intel_csr *csr;
 
-	if (!HAS_CSR(dev_priv)) {
-		seq_puts(m, "not supported\n");
-		return 0;
-	}
+	if (!HAS_CSR(dev_priv))
+		return -ENODEV;
 
 	csr = &dev_priv->csr;
 
@@ -3357,7 +3356,7 @@ static int i915_ddb_info(struct seq_file *m, void *unused)
 	int plane;
 
 	if (INTEL_GEN(dev_priv) < 9)
-		return 0;
+		return -ENODEV;
 
 	drm_modeset_lock_all(dev);
 
-- 
2.7.4