[PATCH 2/2] miitool: Add support for examing mdio bus

[Sascha Hauer]

On Fri, Feb 08, 2013 at 12:02:20PM +0100, Alexander Aring wrote:
> Hi Sascha,
> 
> On Fri, Feb 08, 2013 at 10:24:17AM +0100, Sascha Hauer wrote:
> > Current miitool usage is limited to a single phy on a mdio bus.
> > 
> > For debugging purposes it is useful to be able to examine a mdio bus
> > instead of a single phy only.
> > 
> > This adds support for this to the miitool command.
> > 
> > Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> > ---
> >  commands/miitool.c |   94 +++++++++++++++++++++++++++++++++++++++++-----------
> >  1 file changed, 75 insertions(+), 19 deletions(-)
> > 
> > diff --git a/commands/miitool.c b/commands/miitool.c
> > index 3a9ac45..b9e2333 100644
> > --- a/commands/miitool.c
> > +++ b/commands/miitool.c
> > @@ -37,23 +37,36 @@
> >  #include <linux/stat.h>
> >  #include <xfuncs.h>
> >  #include <linux/mii.h>
> > +#include <linux/phy.h>
> >  
> > -static u16 mdio_read(int fd, int offset)
> > +static int phy_fd;
> > +
> > +static u16 mdio_file_read(int offset)
> >  {
> >  	int ret;
> >  	u16 buf;
> >  
> > -	ret = lseek(fd, offset << 1, SEEK_SET);
> > +	ret = lseek(phy_fd, offset << 1, SEEK_SET);
> >  	if (ret < 0)
> >  		return 0;
> >  
> > -	ret = read(fd, &buf, sizeof(u16));
> > +	ret = read(phy_fd, &buf, sizeof(u16));
> >  	if (ret < 0)
> >  		return 0;
> >  
> >  	return buf;
> >  }
> 
> I made a similar function in nandtest and I am thinking about to add a
> pread and pwrite into file operations.
> Is it welcome to send patches for adding pwrite and pread into file
> operations? I would implement it like this but with a prototype
> which looks like:
> 
> ssize_t pread(int fildes, void *buf, size_t nbyte, off_t offset);

Sounds good. Just to be sure: With 'file operations' you do not mean
struct file_operations, right?

> 
> 
> Another thing:
> You drop the errno in this function. I don't know about the driver bus
> implementation if it can return -EIO or -EBUSY. I know it's not easy to
> handle it because you return the buffer. But we can change the function
> like this:
> 
> static int mdio_file_read(int offset, u16 *buf); to handle error.
> 
> It's only a small thing that I detected.

Ok, can fix this.

Sascha

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