Re: [PATCH v2 5/6] drivers/hv/vmbus: Get the irq number from DeviceTree

[Saurabh Singh Sengar]

On Tue, May 14, 2024 at 03:43:52PM -0700, Roman Kisel wrote:
> The vmbus driver uses ACPI for interrupt assignment on

In subject use the prefix "Drivers: hv: vmbus:".
It is preferred to us "VMbus/VMBus" instead of "vmbus" for all the
commit message and comments.

> arm64 hence it won't function in the VTL mode where only
> DeviceTree can be used.
> 
> Update the vmbus driver to discover interrupt configuration
> via DeviceTree.
> 
> Signed-off-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/hv/vmbus_drv.c | 37 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index e25223cee3ab..52f01bd1c947 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -36,6 +36,7 @@
>  #include <linux/syscore_ops.h>
>  #include <linux/dma-map-ops.h>
>  #include <linux/pci.h>
> +#include <linux/of_irq.h>
>  #include <clocksource/hyperv_timer.h>
>  #include <asm/mshyperv.h>
>  #include "hyperv_vmbus.h"
> @@ -2316,6 +2317,34 @@ static int vmbus_acpi_add(struct platform_device *pdev)
>  }
>  #endif
>  
> +static int __maybe_unused vmbus_of_set_irq(struct device_node *np)
> +{
> +	struct irq_desc *desc;
> +	int irq;
> +
> +	irq = of_irq_get(np, 0);
> +	if (irq == 0) {
> +		pr_err("VMBus interrupt mapping failure\n");
> +		return -EINVAL;
> +	}
> +	if (irq < 0) {
> +		pr_err("VMBus interrupt data can't be read from DeviceTree, error %d\n", irq);
> +		return irq;
> +	}
> +
> +	desc = irq_to_desc(irq);
> +	if (!desc) {
> +		pr_err("VMBus interrupt description can't be found for virq %d\n", irq);
> +		return -ENODEV;
> +	}
> +
> +	vmbus_irq = irq;
> +	vmbus_interrupt = desc->irq_data.hwirq;
> +	pr_debug("VMBus virq %d, hwirq %d\n", vmbus_irq, vmbus_interrupt);
> +
> +	return 0;
> +}
> +
>  static int vmbus_device_add(struct platform_device *pdev)
>  {
>  	struct resource **cur_res = &hyperv_mmio;
> @@ -2324,12 +2353,20 @@ static int vmbus_device_add(struct platform_device *pdev)
>  	struct device_node *np = pdev->dev.of_node;
>  	int ret;
>  
> +	pr_debug("VMBus is present in DeviceTree\n");
> +
>  	hv_dev = &pdev->dev;
>  
>  	ret = of_range_parser_init(&parser, np);
>  	if (ret)
>  		return ret;
>  
> +#ifndef HYPERVISOR_CALLBACK_VECTOR
> +	ret = vmbus_of_set_irq(np);
> +	if (ret)
> +		return ret;
> +#endif
> +
>  	for_each_of_range(&parser, &range) {
>  		struct resource *res;
>  
> -- 
> 2.45.0
>