[PATCH] drm/logicvc: keep the IRQ within the display resource lifetime

[PATCH] drm/logicvc: keep the IRQ within the display resource lifetime

[Myeonghun Pak]

The managed IRQ is requested before the managed CRTC allocation. Probe
unwind can therefore free the CRTC while the handler remains installed.
Probe errors and remove also disable clocks before devres frees the IRQ.

Request the IRQ after display and vblank initialization. Release it on
registration failure and removal before disabling the clocks. Keep it
installed through atomic shutdown so pending commits can still receive
vblank completion.

This issue was found by static analysis.

Fixes: efeeaefe9be5 ("drm: Add support for the LogiCVC display controller")
Assisted-by: LLM
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
---
Compile-tested with Clang, W=1 (x86_64): logicvc_drm.o and
logicvc_crtc.o. No runtime or hardware testing.

 drivers/gpu/drm/logicvc/logicvc_drm.c | 21 +++++++++++++--------
 drivers/gpu/drm/logicvc/logicvc_drm.h |  1 +
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/logicvc/logicvc_drm.c b/drivers/gpu/drm/logicvc/logicvc_drm.c
index bbebf4fc7f51..cf60bbb9800c 100644
--- a/drivers/gpu/drm/logicvc/logicvc_drm.c
+++ b/drivers/gpu/drm/logicvc/logicvc_drm.c
@@ -366,6 +366,7 @@ static int logicvc_drm_probe(struct platform_device *pdev)
 	drm_dev = &logicvc->drm_dev;
 
 	logicvc->regmap = regmap;
+	logicvc->irq = irq;
 	INIT_LIST_HEAD(&logicvc->layers_list);
 
 	caps = logicvc_drm_caps_match(logicvc);
@@ -385,13 +386,6 @@ static int logicvc_drm_probe(struct platform_device *pdev)
 		goto error_reserved_mem;
 	}
 
-	ret = devm_request_irq(dev, irq, logicvc_drm_irq_handler, 0,
-			       dev_name(dev), logicvc);
-	if (ret) {
-		drm_err(drm_dev, "Failed to request IRQ\n");
-		goto error_clocks;
-	}
-
 	ret = logicvc_drm_config_parse(logicvc);
 	if (ret && ret != -ENODEV) {
 		drm_err(drm_dev, "Failed to parse config\n");
@@ -434,16 +428,26 @@ static int logicvc_drm_probe(struct platform_device *pdev)
 		goto error_clocks;
 	}
 
+	ret = devm_request_irq(dev, irq, logicvc_drm_irq_handler, 0,
+			       dev_name(dev), logicvc);
+	if (ret) {
+		drm_err(drm_dev, "Failed to request IRQ\n");
+		goto error_mode;
+	}
+
 	ret = drm_dev_register(drm_dev, 0);
 	if (ret) {
 		drm_err(drm_dev, "Failed to register DRM device\n");
-		goto error_mode;
+		goto error_irq;
 	}
 
 	drm_client_setup(drm_dev, NULL);
 
 	return 0;
 
+error_irq:
+	devm_free_irq(dev, irq, logicvc);
+
 error_mode:
 	logicvc_mode_fini(logicvc);
 
@@ -466,6 +470,7 @@ static void logicvc_drm_remove(struct platform_device *pdev)
 	drm_dev_unregister(drm_dev);
 	drm_atomic_helper_shutdown(drm_dev);
 
+	devm_free_irq(dev, logicvc->irq, logicvc);
 	logicvc_mode_fini(logicvc);
 
 	logicvc_clocks_unprepare(logicvc);
diff --git a/drivers/gpu/drm/logicvc/logicvc_drm.h b/drivers/gpu/drm/logicvc/logicvc_drm.h
index e0f4787c69f9..f69538e6c0e9 100644
--- a/drivers/gpu/drm/logicvc/logicvc_drm.h
+++ b/drivers/gpu/drm/logicvc/logicvc_drm.h
@@ -53,6 +53,7 @@ struct logicvc_drm {
 	struct drm_device drm_dev;
 	phys_addr_t reserved_mem_base;
 	struct regmap *regmap;
+	int irq;
 
 	struct clk *vclk;
 	struct clk *vclk2;