Messages in this thread | | | Date | Mon, 09 Jul 2012 11:24:45 +0800 | From | Lan Tianyu <> | Subject | Re: Fwd: Hid over I2C and ACPI interaction |
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On 2012年07月06日 13:52, Mika Westerberg wrote: > On Thu, Jul 05, 2012 at 03:01:57PM +0800, Zhang Rui wrote: >> +Note that although these are ACPI devices, we prefer to use PnP drivers >> for them, >> +this is because: >> +1. all the non-ACPI-predefined Devices are exported as PnP devices as >> well >> +2. PnP bus is a well designed bus. Probing via PnP layer saves a lot of >> work >> + for the device driver, e.g. getting& parsing ACPI resources. > > (Nice BKM, thanks for sharing) > > I have few questions about using PnP drivers instead of pure ACPI drivers. > > ACPI 5.0 defined some new resources, for example "Fixed DMA descriptor" > that has information about the request line + channel for the device to > use. Hovewer, PnP drivers pass resources as 'struct resource', which > basically only has start and end - how do you represent all this new stuff > using 'struct resource'? > I think we can add new interface to get acpi specific resources. e.g struct acpi_resource pnp_get_acpi_resource(...). When the pnp acpi devices were initialized, put those acpi specific resources into a new resource list pnpdev->acpi_resources. What pnp_get_acpi_resource does is to get specified type acpi resources and return. We also need to define some acpi resource types.
ACPI_RESOURCE_DMA ACPI_RESOURCE_I2C_SERIALBUS ACPI_RESOURCE_SPI_SERIALBUS ACPI_RESOURCE_UART_SERIALBUS ACPI_RESOURCE_COMMON_SERIALBUS ...
How about this? welcome to comments.
> Or should we use acpi_walk_resources() where 'struct resource' is not > suitable? >
-- Best Regards Tianyu Lan linux kernel enabling team -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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