drm/msm/dpu: extract dpu_core_irq_is_valid() helper

In preparation to reworking IRQ indices, move irq_idx validation to
a separate helper.
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/550929/
Link: https://lore.kernel.org/r/20230802100426.4184892-4-dmitry.baryshkov@linaro.org

drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c

@@ -200,6 +200,12 @@ static const struct dpu_intr_reg dpu_intr_set_7xxx[] = {
 #define DPU_IRQ_REG(irq_idx)	(irq_idx / 32)
 #define DPU_IRQ_MASK(irq_idx)	(BIT(irq_idx % 32))
 
+static inline bool dpu_core_irq_is_valid(struct dpu_hw_intr *intr,
+					 int irq_idx)
+{
+	return irq_idx >= 0 && irq_idx < intr->total_irqs;
+}
+
 /**
  * dpu_core_irq_callback_handler - dispatch core interrupts
  * @dpu_kms:		Pointer to DPU's KMS structure
@@ -291,7 +297,7 @@ static int dpu_hw_intr_enable_irq_locked(struct dpu_hw_intr *intr, int irq_idx)
 	if (!intr)
 		return -EINVAL;
 
-	if (irq_idx < 0 || irq_idx >= intr->total_irqs) {
+	if (!dpu_core_irq_is_valid(intr, irq_idx)) {
 		pr_err("invalid IRQ index: [%d]\n", irq_idx);
 		return -EINVAL;
 	}
@@ -344,7 +350,7 @@ static int dpu_hw_intr_disable_irq_locked(struct dpu_hw_intr *intr, int irq_idx)
 	if (!intr)
 		return -EINVAL;
 
-	if (irq_idx < 0 || irq_idx >= intr->total_irqs) {
+	if (!dpu_core_irq_is_valid(intr, irq_idx)) {
 		pr_err("invalid IRQ index: [%d]\n", irq_idx);
 		return -EINVAL;
 	}
@@ -429,13 +435,7 @@ u32 dpu_core_irq_read(struct dpu_kms *dpu_kms, int irq_idx)
 	if (!intr)
 		return 0;
 
-	if (irq_idx < 0) {
-		DPU_ERROR("[%pS] invalid irq_idx=%d\n",
-				__builtin_return_address(0), irq_idx);
-		return 0;
-	}
-
-	if (irq_idx < 0 || irq_idx >= intr->total_irqs) {
+	if (!dpu_core_irq_is_valid(intr, irq_idx)) {
 		pr_err("invalid IRQ index: [%d]\n", irq_idx);
 		return 0;
 	}
@@ -518,7 +518,7 @@ int dpu_core_irq_register_callback(struct dpu_kms *dpu_kms, int irq_idx,
 		return -EINVAL;
 	}
 
-	if (irq_idx < 0 || irq_idx >= dpu_kms->hw_intr->total_irqs) {
+	if (!dpu_core_irq_is_valid(dpu_kms->hw_intr, irq_idx)) {
 		DPU_ERROR("invalid IRQ index: [%d]\n", irq_idx);
 		return -EINVAL;
 	}
@@ -555,7 +555,7 @@ int dpu_core_irq_unregister_callback(struct dpu_kms *dpu_kms, int irq_idx)
 	unsigned long irq_flags;
 	int ret;
 
-	if (irq_idx < 0 || irq_idx >= dpu_kms->hw_intr->total_irqs) {
+	if (!dpu_core_irq_is_valid(dpu_kms->hw_intr, irq_idx)) {
 		DPU_ERROR("invalid IRQ index: [%d]\n", irq_idx);
 		return -EINVAL;
 	}