bus: mhi: core: Check for IRQ availability during registration

Current design allows a controller to register with MHI successfully
without the need to have any IRQs available for use. If no IRQs are
available, power up requests to MHI can fail after a successful
registration with MHI. Improve the design by checking for the number
of IRQs available sooner within the mhi_regsiter_controller() API as
it is required to be specified by the controller.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

drivers/bus/mhi/core/init.c

@@ -858,7 +858,7 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
 
 	if (!mhi_cntrl->runtime_get || !mhi_cntrl->runtime_put ||
 	    !mhi_cntrl->status_cb || !mhi_cntrl->read_reg ||
-	    !mhi_cntrl->write_reg)
+	    !mhi_cntrl->write_reg || !mhi_cntrl->nr_irqs)
 		return -EINVAL;
 
 	ret = parse_config(mhi_cntrl, config);

drivers/bus/mhi/core/pm.c

@@ -926,9 +926,6 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
 
 	dev_info(dev, "Requested to power ON\n");
 
-	if (mhi_cntrl->nr_irqs < 1)
-		return -EINVAL;
-
 	/* Supply default wake routines if not provided by controller driver */
 	if (!mhi_cntrl->wake_get || !mhi_cntrl->wake_put ||
 	    !mhi_cntrl->wake_toggle) {