irqchip/tb10x: Use 'fallthrough' to eliminate a warning

Use the 'fallthrough' macro to document that this switch case
does indeed fall through to the next case.

../drivers/irqchip/irq-tb10x.c: In function 'tb10x_irq_set_type':
../drivers/irqchip/irq-tb10x.c:62:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   62 |   flow_type = IRQ_TYPE_LEVEL_LOW;
../drivers/irqchip/irq-tb10x.c:63:2: note: here
   63 |  case IRQ_TYPE_LEVEL_LOW:
      |  ^~~~

Fixes: b06eb0173ef1 ("irqchip: Add TB10x interrupt controller driver")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210422051620.23021-1-rdunlap@infradead.org

diff --git a/drivers/irqchip/irq-tb10x.c b/drivers/irqchip/irq-tb10x.c
index 9e45649..9a63b02 100644 (file)
--- a/drivers/irqchip/irq-tb10x.c
+++ b/drivers/irqchip/irq-tb10x.c
@@ -60,6 +60,7 @@ static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type)
                break;
        case IRQ_TYPE_NONE:
                flow_type = IRQ_TYPE_LEVEL_LOW;
+               fallthrough;
        case IRQ_TYPE_LEVEL_LOW:
                mod ^= im;
                pol ^= im;