Re: How do I choose an arbitrary minor number for my tty device?

[Michael Ellerman <michael@ellerman.id.au>]

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On Wed, 2010-11-24 at 10:23 -0800, Greg KH wrote:
> On Wed, Nov 24, 2010 at 12:08:18PM -0600, Scott Wood wrote:
> > On Wed, 24 Nov 2010 21:23:47 +1100
> > Michael Ellerman <michael@ellerman.id.au> wrote:
> > 
> > > On Thu, 2010-11-18 at 12:13 -0600, Scott Wood wrote:
> > > > Unfortunately, it's not an exact match, and the fact that reg doesn't
> > > > translate to a physical address means that AFAICT you'll currently get
> > > > something like "byte-channel.nnn", where "nnn" is an arbitrary
> > > > kernel-assigned number.
> > > 
> > > Can you not use device_rename() ?
> > 
> > Ah, didn't know about that.  Still, might be nice to add support for
> > "handle" nodes at the infrastructure level rather than in each driver.
> 
> No, please never use that function, bad things will happen.

Why? The network & wireless code uses it, so presumably it can work? If
not please consider:

commit f470f680dfaad8731f079a033a50440082e20930
Author: Michael Ellerman <michael@ellerman.id.au>
Date:   Thu Nov 25 09:41:28 2010 +1100

    driver core: Document that device_rename() is not to be used
    
    Signed-off-by: Michael Ellerman <michael@ellerman.id.au>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 6ed6454..f1fac19 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1513,6 +1513,8 @@ EXPORT_SYMBOL_GPL(device_destroy);
  * exclusion between two different calls of device_rename
  * on the same device to ensure that new_name is valid and
  * won't conflict with other devices.
+ *
+ * "Never use this function, bad things will happen" - gregkh
  */
 int device_rename(struct device *dev, const char *new_name)
 {


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