[1/6] spi: imx: specify spi base for device tree probe

Commit Message

Steffen Trumtrar Nov. 9, 2012, 2 p.m. UTC

The DT probe uses a dynamically allocated base for the spi core. This is a
completely different numbering scheme than in the non-DT probe.

* This breaks compatibility with user space applications between non-DT and DT.

* On platforms that are in between DT and non-DT, it breaks registration of
  devices via spi_board_info.

Use the same method as 7e6086d9e54a159a6257c02bb7fc5805c614aad2 does for gpios:
Use alias to identify the spi port, and then specify the base via the port id.
If alias is not defined in DT, allocate the base dynamically.

Signed-off-by: Steffen Trumtrar <[e-mail]>
---
 drivers/spi/spi-imx.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Mark Brown Nov. 9, 2012, 4:38 p.m. UTC | #1

On Fri, Nov 09, 2012 at 03:00:20PM +0100, Steffen Trumtrar wrote:

> * This breaks compatibility with user space applications between non-DT and DT.

> * On platforms that are in between DT and non-DT, it breaks registration of
>   devices via spi_board_info.

> Use the same method as 7e6086d9e54a159a6257c02bb7fc5805c614aad2 does for gpios:
> Use alias to identify the spi port, and then specify the base via the port id.
> If alias is not defined in DT, allocate the base dynamically.

This sounds like a fix userspace and/or complete your DT conversion
problem...

Steffen Trumtrar Nov. 9, 2012, 7 p.m. UTC | #2

On Fri, Nov 09, 2012 at 04:38:30PM +0000, Mark Brown wrote:
> On Fri, Nov 09, 2012 at 03:00:20PM +0100, Steffen Trumtrar wrote:
> 
> > * This breaks compatibility with user space applications between non-DT and DT.
> 
> > * On platforms that are in between DT and non-DT, it breaks registration of
> >   devices via spi_board_info.
> 
> > Use the same method as 7e6086d9e54a159a6257c02bb7fc5805c614aad2 does for gpios:
> > Use alias to identify the spi port, and then specify the base via the port id.
> > If alias is not defined in DT, allocate the base dynamically.
> 
> This sounds like a fix userspace and/or complete your DT conversion
> problem...

Well, it may lead to problems in userspace and does lead to problems with an
incomplete DT support, but there are only so many hours in a day...

Patch

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index c9a0d84..d1e92b4 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -783,7 +783,7 @@  static int __devinit spi_imx_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, master);
 
-	master->bus_num = pdev->id;
+	master->bus_num = (pdev->id < 0) ? of_alias_get_id(np, "spi") : pdev->id;
 	master->num_chipselect = num_cs;
 
 	spi_imx = spi_master_get_devdata(master);