greybus: gpio: remove unused irq-ack operation

Remove unused irq-ack operation, which has never been called and does
not make sense for message-signalled interrupts over slow buses.
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/gpio.c

@@ -211,21 +211,6 @@ static int gb_gpio_set_debounce_operation(struct gb_gpio_controller *ggc,
 	return ret;
 }
 
-static void gb_gpio_ack_irq(struct irq_data *d)
-{
-	struct gpio_chip *chip = irq_data_to_gpio_chip(d);
-	struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
-	struct gb_gpio_irq_ack_request request;
-	int ret;
-
-	request.which = d->hwirq;
-	ret = gb_operation_sync(ggc->connection,
-				GB_GPIO_TYPE_IRQ_ACK,
-				&request, sizeof(request), NULL, 0);
-	if (ret)
-		dev_err(chip->dev, "failed to ack irq: %d\n", ret);
-}
-
 static void gb_gpio_mask_irq(struct irq_data *d)
 {
 	struct gpio_chip *chip = irq_data_to_gpio_chip(d);
@@ -591,7 +576,6 @@ static int gb_gpio_connection_init(struct gb_connection *connection)
 		goto err_free_controller;
 
 	irqc = &ggc->irqc;
-	irqc->irq_ack = gb_gpio_ack_irq;
 	irqc->irq_mask = gb_gpio_mask_irq;
 	irqc->irq_unmask = gb_gpio_unmask_irq;
 	irqc->irq_set_type = gb_gpio_irq_set_type;

drivers/staging/greybus/greybus_protocols.h

@@ -128,7 +128,6 @@ struct gb_i2c_transfer_response {
 #define GB_GPIO_TYPE_SET_VALUE		0x09
 #define GB_GPIO_TYPE_SET_DEBOUNCE	0x0a
 #define GB_GPIO_TYPE_IRQ_TYPE		0x0b
-#define GB_GPIO_TYPE_IRQ_ACK		0x0c
 #define GB_GPIO_TYPE_IRQ_MASK		0x0d
 #define GB_GPIO_TYPE_IRQ_UNMASK		0x0e
 #define GB_GPIO_TYPE_IRQ_EVENT		0x0f
@@ -203,11 +202,6 @@ struct gb_gpio_irq_unmask_request {
 };
 /* irq unmask response has no payload */
 
-struct gb_gpio_irq_ack_request {
-	__u8	which;
-};
-/* irq ack response has no payload */
-
 /* irq event requests originate on another module and are handled on the AP */
 struct gb_gpio_irq_event_request {
 	__u8	which;