With Ismo's patch applied, I added a few printk statements to spi.c and resource.c (the lines beginning with xxx). modprobe pxa2xx-spi-pci pxa2xx-spi pxa2xx-spi.0: found DMA channel "tx" at index 0 xxx resource.c acpi_dev_get_resources acpi_handle is ffff8802650bdcd0 returns c.count 0... dma dma0chan0: dwc_alloc_chan_resources: allocated 64 descriptors dmaengine: __dma_request_channel: success (dma0chan0) pxa2xx-spi pxa2xx-spi.0: found DMA channel "rx" at index 1 xxx resource.c acpi_dev_get_resources acpi_handle is ffff8802650bdcd0 returns c.count 0... dmaengine: private_candidate: dma0chan0 busy dma dma0chan1: dwc_alloc_chan_resources: allocated 64 descriptors dmaengine: __dma_request_channel: success (dma0chan1) pxa2xx-spi pxa2xx-spi.0: registered master spi0 xxx spi.c acpi_register_spi_devices acpi_handle is ffff8802650bdcd0 xxx resource.c acpi_dev_get_resources acpi_handle is ffff8802650bf000 returns c.count 0... I believe these acpi handle values correspond to: ffff8802650bdcd0 = INT33C1/SPI controller ffff8802650bf000 = APP000D/SPI slave spi.c did find the slave device, as this statement was not evaluated: if (ACPI_FAILURE(status)) dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); However, the slave device is never enumerated. Do you know how I could print out the the name or id of the ACPI device from the acpi_device pointer? **I'm struggling a bit with some of these data types I'll continue to debug this issue a bit more... On Mon, Feb 29, 2016 at 6:21 PM, Leif Liddy <leif.linux@xxxxxxxxx> wrote: > I debugged acpi_lpss.c as it attempted to created a platform device for INT33C1. > > I got as far as this function in resouce.c > status = acpi_walk_resources(adev->handle, METHOD_NAME__CRS, > acpi_dev_process_resource, &c); > > the value of c never gets incremented --and returns 0. > > I'm not sure how closely apcia follows the logic of these tables and > whether the OSI value is actually checked or not. > If WBUF is being returned, then that would be the source of the issue. > > > Device (SDMA) > { > Name (_ADR, 0x00150000) // _ADR: Address > Name (_UID, 0x01) // _UID: Unique ID > Name (RBUF, ResourceTemplate () > ... > Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings > { > Return (RBUF) /* \_SB_.PCI0.SDMA.RBUF */ > } > ... > Device (SPI1) > { > Name (_ADR, 0x00150004) // _ADR: Address > Name (_CID, "INT33C1" /* Intel Serial I/O SPI Host Controller */) > .. > Name (WBUF, ResourceTemplate () > { > }) > Name (DBUF, ResourceTemplate () > { > FixedDMA (0x0010, 0x0006, Width32bit, ) > FixedDMA (0x0011, 0x0007, Width32bit, ) > }) > Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings > { > If (!OSDW ()) > { > Return (WBUF) /* \_SB_.PCI0.SPI1.WBUF */ > } > > Return (ConcatenateResTemplate (RBUF, DBUF)) > } > } > ...... > > > In any case, it sounds like the best approach is just to go with the > spi-pxa2xx-pci driver. > >>>I believe passing the ACPI handle to the platform device is the real >>fix. > > Ok, I understand what this means now --and I know what the acpi handle > is for INT33C1. > I'm going to try and modify spi.c to use this acpi handle --and > hopefully it will find the SPI slave device. > > handle = ACPI_HANDLE(master->dev.parent); > > status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, > acpi_spi_add_device, NULL, > master, NULL); > > On Mon, Feb 29, 2016 at 9:21 AM, Mika Westerberg > <mika.westerberg@xxxxxxxxxxxxxxx> wrote: >> On Tue, Feb 23, 2016 at 09:30:40PM +0100, Leif Liddy wrote: >>> I'm beginning to understand how this is meant to work. >>> >>> spi_pxa2xx_platform should by itself be able to setup the SPI controller. >>> **it has the ACPI ID for it >>> { "INT33C1", LPSS_LPT_SSP } >>> >>> When I modprobe spi_pxa2xx_platform >>> pxa2xx_spi_probe never gets called, there must be an issue with: >>> acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match) >> >> That's fine - the device is a PCI device and does not require ACPI ID. >> However, the PCI part of the driver creates this platform device for >> spi_pxa2xx_platform. >> >>> Ok, so I've installed Ismo's one line patch >>> >>> dmesg log of "modprobe spi_pxa2xx_pci" >>> >>> pxa2xx-spi pxa2xx-spi.0: found DMA channel "tx" at index 0 >>> dma dma0chan0: dwc_alloc_chan_resources: allocated 64 descriptors >>> dmaengine: __dma_request_channel: success (dma0chan0) >>> pxa2xx-spi pxa2xx-spi.0: found DMA channel "rx" at index 1 >>> dmaengine: private_candidate: dma0chan0 busy >>> dma dma0chan1: dwc_alloc_chan_resources: allocated 64 descriptors >>> dmaengine: __dma_request_channel: success (dma0chan1) >> >> Difference is that with Ismo's patch you actually have ACPI handle for >> the device so it tries to use ACPI to look for the DMA channels. >> >>> without the patch: >>> >>> dma dma0chan0: dwc_alloc_chan_resources: allocated 64 descriptors >>> dmaengine: __dma_request_channel: success (dma0chan0) >>> dmaengine: private_candidate: dma0chan0 busy >>> dma dma0chan1: dwc_alloc_chan_resources: allocated 64 descriptors >>> dmaengine: __dma_request_channel: success (dma0chan1) >> >> Here it uses hardcoded indices instead. In both cases result is the >> same. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html