[PATCH 1/6] gpio/mxs: adopt irq_domain support for mxs gpio driver

On Tue, Aug 21, 2012 at 08:16:37AM -0500, Rob Herring wrote:

On 08/21/2012 08:01 AM, Linus Walleij wrote:

quoted

On Mon, Aug 20, 2012 at 4:19 PM, Shawn Guo [off-list ref] wrote:

quoted

Remove irq_domain_add_legacy call from mach-mxs.c and have the gpio
driver adopt irqdomain support, so that we can have the mapping
between gpio and irq number available without using virtual_irq_start
and MXS_GPIO_IRQ_START.

Seems like a good thing to do, but with Grant and Rob being better at
irqdomain than me I'd prefer one of them to have a look at this too.

quoted

+       irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
+       if (irq_base < 0)
+               return irq_base;
+
+       port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
+                                            &irq_domain_simple_ops, NULL);

For example I want to understand if it'd be possible to use a
linear domain here.

Unfortunately, not if you care about your irq base and need sequential
irq numbers which is the case for non-DT.

Right.  For for this particular case, it's more because generic-chip
currently does not cope with the driver using linear domain.

-- 
Regards,
Shawn