Messages in this thread Patch in this message | | | Date | Mon, 08 Nov 2010 14:29:11 +0100 | From | Michal Simek <> | Subject | Re: [RFC PATCH 0/3] spi/xilinx: Merge OF and non-OF drivers |
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Hi Grant,
Grant Likely wrote: > Since of_platform_bus_type has been merged with the platform_bus_type, > a single platform driver can now support both use cases. This patch > series merges the two halves of the xilinx_spi device driver. > > Compile tested only. I haven't booted this yet.
I have tested it on sp605 and works well. Have you added that patches to your repository? Or are they somewhere else? Who is responsible for?
I would like to also discuss one change which is related mmc_spi kernel driver. Let me describe the problem. Microblaze can use dma in all addresses that's why dma_mask is setup to 0xffffffff in of_platform_device_create. Xilinx spi driver doesn't support dma but mmc_spi driver is checking dma_mask in parent device which is xilinx spi driver.
Here is the corresponding the part of code (Expect dma_mask=zero for no dma operations). mmc_spi.c:~1395 if (spi->master->dev.parent->dma_mask) { struct device *dev = spi->master->dev.parent;
host->dma_dev = dev;
Based on this one our customer came with the following solution to setup dma_mask in xilinx_spi to zero and then mmc_spi doesn't setup dma operation.
I think that this is nice solution but I would like to be sure that I didn't miss anything. After that i will create proper patch with description.
diff --git a/drivers/spi/xilinx_spi.c b/drivers/spi/xilinx_spi.c index 7adaef6..3612e1b 100644 --- a/drivers/spi/xilinx_spi.c +++ b/drivers/spi/xilinx_spi.c @@ -519,6 +519,9 @@ static int __devinit xilinx_spi_probe(struct platform_device *dev) }
platform_set_drvdata(dev, master); + /* clear the dma_mask, to try to disable use of dma */ + dev->dev.dma_mask = 0; + return 0; }
Thanks, Michal
-- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/ Microblaze U-BOOT custodian
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