GPIO on the Au1500

GPIO on the Au1500

[Gilad Rom]

Hello,

I am trying to use the au1000_gpio driver, but I'm a little
clueless as to how it is meant to be used. Can I use the GPIO
ioctl's from a userland program, or must I write a kernel module?

Thank you,
Gilad Rom
Romat Telecom

GPIO on the Au1500

[Gilad Rom]

Hello,

I am trying to use the au1000_gpio driver, but I'm a little
clueless as to how it is meant to be used. Can I use the GPIO
ioctl's from a userland program, or must I write a kernel module?

Thank you,
Gilad Rom
Romat Telecom

Re: GPIO on the Au1500

[Pete Popov]

--- Gilad Rom <gilad@romat.com> wrote:

> Hello,
> 
> I am trying to use the au1000_gpio driver, but I'm a
> little clueless as to how it is meant to be used. 
> Can I use the GPIO ioctl's from a userland 
> program, or must I write a kernel module?

I'll see if I can dig up some docs and the example
userland program this weekend. That driver hasn't been
tested in a while though.

Pete

> Thank you,
> Gilad Rom
> Romat Telecom
> 
> 
> 

Re: GPIO on the Au1500

[Gilad Rom]

Thanks. 
Can't I just mmap /dev/mem and use the
GPIO offset from SYS_BASE?

Gilad.

----- Original Message ----- 
From: "Pete Popov" <ppopov@embeddedalley.com>
To: "Gilad Rom" <gilad@romat.com>; <linux-mips@linux-mips.org>
Sent: Friday, November 12, 2004 8:13 PM
Subject: Re: GPIO on the Au1500


> 
> --- Gilad Rom <gilad@romat.com> wrote:
> 
>> Hello,
>> 
>> I am trying to use the au1000_gpio driver, but I'm a
>> little clueless as to how it is meant to be used. 
>> Can I use the GPIO ioctl's from a userland 
>> program, or must I write a kernel module?
> 
> I'll see if I can dig up some docs and the example
> userland program this weekend. That driver hasn't been
> tested in a while though.
> 
> Pete
> 
>> Thank you,
>> Gilad Rom
>> Romat Telecom
>> 
>> 
>> 
>

Re: GPIO on the Au1500

[Gilad Rom]

Thanks. 
Can't I just mmap /dev/mem and use the
GPIO offset from SYS_BASE?

Gilad.

----- Original Message ----- 
From: "Pete Popov" <ppopov@embeddedalley.com>
To: "Gilad Rom" <gilad@romat.com>; <linux-mips@linux-mips.org>
Sent: Friday, November 12, 2004 8:13 PM
Subject: Re: GPIO on the Au1500


> 
> --- Gilad Rom <gilad@romat.com> wrote:
> 
>> Hello,
>> 
>> I am trying to use the au1000_gpio driver, but I'm a
>> little clueless as to how it is meant to be used. 
>> Can I use the GPIO ioctl's from a userland 
>> program, or must I write a kernel module?
> 
> I'll see if I can dig up some docs and the example
> userland program this weekend. That driver hasn't been
> tested in a while though.
> 
> Pete
> 
>> Thank you,
>> Gilad Rom
>> Romat Telecom
>> 
>> 
>> 
>

Re: GPIO on the Au1500

[Gilad Rom]

Replying to myself - 

I've composed a small program which mmap()'s
SYS_BASE and then tries to read at the appropriate
GPIO offset, as defined in the Au1500 databook.

For some reason, I keep getting that magical value, 
0x10000001 for EVERY address I try to read, be it 
SYS_BASE (0xB1900000) or every other address. (for example,
I've tried reading the MAC address from the MAC0 base address
of 0xB1500000, offset 0x0008, and I always get 0x10000001).

Any reason I shouldn't succeed in reading the au1500 
hardware addresses through /dev/mem?

Attached is the code I'm using:

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>

#define SYS_BASE     0xB1900000

int
main () 
{
 volatile unsigned long *base;
 unsigned char val;
 int f, i;

 f = open ("/dev/mem", O_RDWR | O_SYNC);
 if (f < 0) {
  perror ("fopen");
  exit (-1);
 }
 
 base = (unsigned long *) mmap (NULL, 
   getpagesize (), 
   PROT_READ | PROT_WRITE, 
   MAP_SHARED, 
   f,
   SYS_BASE);

 if (base == (unsigned long *) (-1)) {
  perror ("mmap");
  exit (-1);
 }

 printf ("data at %p: 0x%x\n", base, (unsigned long) *base);
 *base = 0xffffffff;
        printf ("data at %p: 0x%x\n", base, (unsigned long) *base);
 close (f);
 return (0);
}

Thanks!
Gilad.

----- Original Message ----- 
From: "Gilad Rom" <gilad@romat.com>
To: <ppopov@embeddedalley.com>; <linux-mips@linux-mips.org>
Sent: Sunday, November 14, 2004 10:35 AM
Subject: Re: GPIO on the Au1500


> Thanks. 
> Can't I just mmap /dev/mem and use the
> GPIO offset from SYS_BASE?
> 
> Gilad.
> 
> ----- Original Message ----- 
> From: "Pete Popov" <ppopov@embeddedalley.com>
> To: "Gilad Rom" <gilad@romat.com>; <linux-mips@linux-mips.org>
> Sent: Friday, November 12, 2004 8:13 PM
> Subject: Re: GPIO on the Au1500
> 
> 
>> 
>> --- Gilad Rom <gilad@romat.com> wrote:
>> 
>>> Hello,
>>> 
>>> I am trying to use the au1000_gpio driver, but I'm a
>>> little clueless as to how it is meant to be used. 
>>> Can I use the GPIO ioctl's from a userland 
>>> program, or must I write a kernel module?
>> 
>> I'll see if I can dig up some docs and the example
>> userland program this weekend. That driver hasn't been
>> tested in a while though.
>> 
>> Pete
>> 
>>> Thank you,
>>> Gilad Rom
>>> Romat Telecom
>>> 
>>> 
>>> 
>>
>

Re: GPIO on the Au1500

[Gilad Rom]

Replying to myself - 

I've composed a small program which mmap()'s
SYS_BASE and then tries to read at the appropriate
GPIO offset, as defined in the Au1500 databook.

For some reason, I keep getting that magical value, 
0x10000001 for EVERY address I try to read, be it 
SYS_BASE (0xB1900000) or every other address. (for example,
I've tried reading the MAC address from the MAC0 base address
of 0xB1500000, offset 0x0008, and I always get 0x10000001).

Any reason I shouldn't succeed in reading the au1500 
hardware addresses through /dev/mem?

Attached is the code I'm using:

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>

#define SYS_BASE     0xB1900000

int
main () 
{
 volatile unsigned long *base;
 unsigned char val;
 int f, i;

 f = open ("/dev/mem", O_RDWR | O_SYNC);
 if (f < 0) {
  perror ("fopen");
  exit (-1);
 }
 
 base = (unsigned long *) mmap (NULL, 
   getpagesize (), 
   PROT_READ | PROT_WRITE, 
   MAP_SHARED, 
   f,
   SYS_BASE);

 if (base == (unsigned long *) (-1)) {
  perror ("mmap");
  exit (-1);
 }

 printf ("data at %p: 0x%x\n", base, (unsigned long) *base);
 *base = 0xffffffff;
        printf ("data at %p: 0x%x\n", base, (unsigned long) *base);
 close (f);
 return (0);
}

Thanks!
Gilad.

----- Original Message ----- 
From: "Gilad Rom" <gilad@romat.com>
To: <ppopov@embeddedalley.com>; <linux-mips@linux-mips.org>
Sent: Sunday, November 14, 2004 10:35 AM
Subject: Re: GPIO on the Au1500


> Thanks. 
> Can't I just mmap /dev/mem and use the
> GPIO offset from SYS_BASE?
> 
> Gilad.
> 
> ----- Original Message ----- 
> From: "Pete Popov" <ppopov@embeddedalley.com>
> To: "Gilad Rom" <gilad@romat.com>; <linux-mips@linux-mips.org>
> Sent: Friday, November 12, 2004 8:13 PM
> Subject: Re: GPIO on the Au1500
> 
> 
>> 
>> --- Gilad Rom <gilad@romat.com> wrote:
>> 
>>> Hello,
>>> 
>>> I am trying to use the au1000_gpio driver, but I'm a
>>> little clueless as to how it is meant to be used. 
>>> Can I use the GPIO ioctl's from a userland 
>>> program, or must I write a kernel module?
>> 
>> I'll see if I can dig up some docs and the example
>> userland program this weekend. That driver hasn't been
>> tested in a while though.
>> 
>> Pete
>> 
>>> Thank you,
>>> Gilad Rom
>>> Romat Telecom
>>> 
>>> 
>>> 
>>
>

Re: GPIO on the Au1500

[Charles Eidsness]

Hi Gilad,

A little while ago I wrote my own GPIO driver for the Au1000, mainly as 
a learning experience. I never bothered to release it because a driver 
already exists and I thought it was working. I'm not sure if it will 
work on the Au1550, but if you're interested you can find the source 
code here:

http://members.rogers.com/charles.eidsness/au1000_gpio.c
http://members.rogers.com/charles.eidsness/au1000_gpio.h

Cheers,
Charles

Gilad Rom wrote:
> Thanks. Can't I just mmap /dev/mem and use the
> GPIO offset from SYS_BASE?
> 
> Gilad.
> 
> ----- Original Message ----- From: "Pete Popov" <ppopov@embeddedalley.com>
> To: "Gilad Rom" <gilad@romat.com>; <linux-mips@linux-mips.org>
> Sent: Friday, November 12, 2004 8:13 PM
> Subject: Re: GPIO on the Au1500
> 
> 
>>
>> --- Gilad Rom <gilad@romat.com> wrote:
>>
>>> Hello,
>>>
>>> I am trying to use the au1000_gpio driver, but I'm a
>>> little clueless as to how it is meant to be used. Can I use the GPIO 
>>> ioctl's from a userland program, or must I write a kernel module?
>>
>>
>> I'll see if I can dig up some docs and the example
>> userland program this weekend. That driver hasn't been
>> tested in a while though.
>>
>> Pete
>>
>>> Thank you,
>>> Gilad Rom
>>> Romat Telecom
>>>
>>>
>>>
>>
> 
> 
> 

Re: GPIO on the Au1500

[Pete Popov]

--- Charles Eidsness <charles.eidsness@ieee.org>
wrote:

> Hi Gilad,
> 
> A little while ago I wrote my own GPIO driver for
> the Au1000, mainly as a learning experience. I 
> never bothered to release it because a driver 
> already exists and I thought it was working. 

It was, a long time ago, when it was written for the
Au1000. I had a user app and doc somewhere but can't
find it anymore. The driver didn't support gpio2 and
was, in general, stale. So perhaps your driver will
help Gilad.

Pete

> I'm not sure if it will 
> work on the Au1550, but if you're interested you can
> find the source 
> code here:
> 
>
http://members.rogers.com/charles.eidsness/au1000_gpio.c
>
http://members.rogers.com/charles.eidsness/au1000_gpio.h
> 
> Cheers,
> Charles
> 
> Gilad Rom wrote:
> > Thanks. Can't I just mmap /dev/mem and use the
> > GPIO offset from SYS_BASE?
> > 
> > Gilad.
> > 
> > ----- Original Message ----- From: "Pete Popov"
> <ppopov@embeddedalley.com>
> > To: "Gilad Rom" <gilad@romat.com>;
> <linux-mips@linux-mips.org>
> > Sent: Friday, November 12, 2004 8:13 PM
> > Subject: Re: GPIO on the Au1500
> > 
> > 
> >>
> >> --- Gilad Rom <gilad@romat.com> wrote:
> >>
> >>> Hello,
> >>>
> >>> I am trying to use the au1000_gpio driver, but
> I'm a
> >>> little clueless as to how it is meant to be
> used. Can I use the GPIO 
> >>> ioctl's from a userland program, or must I write
> a kernel module?
> >>
> >>
> >> I'll see if I can dig up some docs and the
> example
> >> userland program this weekend. That driver hasn't
> been
> >> tested in a while though.
> >>
> >> Pete
> >>
> >>> Thank you,
> >>> Gilad Rom
> >>> Romat Telecom
> >>>
> >>>
> >>>
> >>
> > 
> > 
> > 
> 
> 

Re: GPIO on the Au1500

[Gilad Rom]

Thank you for the driver, I'm using it as a reference.

Still, I am trying to acccess the GPIO ports of the Au1500
using /dev/mem, but I keep getting these odd values
(see previous messages to this list)

Do you think it is possible, 
or should I stick to using the driver?


Thank you,
Gilad.

----- Original Message ----- 
From: "Pete Popov" <ppopov@embeddedalley.com>
To: <charles.eidsness@ieee.org>; "Gilad Rom" <gilad@romat.com>
Cc: <linux-mips@linux-mips.org>
Sent: Sunday, November 14, 2004 8:45 PM
Subject: Re: GPIO on the Au1500


> 
> --- Charles Eidsness <charles.eidsness@ieee.org>
> wrote:
> 
>> Hi Gilad,
>> 
>> A little while ago I wrote my own GPIO driver for
>> the Au1000, mainly as a learning experience. I 
>> never bothered to release it because a driver 
>> already exists and I thought it was working. 
> 
> It was, a long time ago, when it was written for the
> Au1000. I had a user app and doc somewhere but can't
> find it anymore. The driver didn't support gpio2 and
> was, in general, stale. So perhaps your driver will
> help Gilad.
> 
> Pete
> 
>> I'm not sure if it will 
>> work on the Au1550, but if you're interested you can
>> find the source 
>> code here:
>> 
>>
> http://members.rogers.com/charles.eidsness/au1000_gpio.c
>>
> http://members.rogers.com/charles.eidsness/au1000_gpio.h
>> 
>> Cheers,
>> Charles
>> 
>> Gilad Rom wrote:
>> > Thanks. Can't I just mmap /dev/mem and use the
>> > GPIO offset from SYS_BASE?
>> > 
>> > Gilad.
>> > 
>> > ----- Original Message ----- From: "Pete Popov"
>> <ppopov@embeddedalley.com>
>> > To: "Gilad Rom" <gilad@romat.com>;
>> <linux-mips@linux-mips.org>
>> > Sent: Friday, November 12, 2004 8:13 PM
>> > Subject: Re: GPIO on the Au1500
>> > 
>> > 
>> >>
>> >> --- Gilad Rom <gilad@romat.com> wrote:
>> >>
>> >>> Hello,
>> >>>
>> >>> I am trying to use the au1000_gpio driver, but
>> I'm a
>> >>> little clueless as to how it is meant to be
>> used. Can I use the GPIO 
>> >>> ioctl's from a userland program, or must I write
>> a kernel module?
>> >>
>> >>
>> >> I'll see if I can dig up some docs and the
>> example
>> >> userland program this weekend. That driver hasn't
>> been
>> >> tested in a while though.
>> >>
>> >> Pete
>> >>
>> >>> Thank you,
>> >>> Gilad Rom
>> >>> Romat Telecom
>> >>>
>> >>>
>> >>>
>> >>
>> > 
>> > 
>> > 
>> 
>> 
> 
>

Re: GPIO on the Au1500

[Gilad Rom]

Thank you for the driver, I'm using it as a reference.

Still, I am trying to acccess the GPIO ports of the Au1500
using /dev/mem, but I keep getting these odd values
(see previous messages to this list)

Do you think it is possible, 
or should I stick to using the driver?


Thank you,
Gilad.

----- Original Message ----- 
From: "Pete Popov" <ppopov@embeddedalley.com>
To: <charles.eidsness@ieee.org>; "Gilad Rom" <gilad@romat.com>
Cc: <linux-mips@linux-mips.org>
Sent: Sunday, November 14, 2004 8:45 PM
Subject: Re: GPIO on the Au1500


> 
> --- Charles Eidsness <charles.eidsness@ieee.org>
> wrote:
> 
>> Hi Gilad,
>> 
>> A little while ago I wrote my own GPIO driver for
>> the Au1000, mainly as a learning experience. I 
>> never bothered to release it because a driver 
>> already exists and I thought it was working. 
> 
> It was, a long time ago, when it was written for the
> Au1000. I had a user app and doc somewhere but can't
> find it anymore. The driver didn't support gpio2 and
> was, in general, stale. So perhaps your driver will
> help Gilad.
> 
> Pete
> 
>> I'm not sure if it will 
>> work on the Au1550, but if you're interested you can
>> find the source 
>> code here:
>> 
>>
> http://members.rogers.com/charles.eidsness/au1000_gpio.c
>>
> http://members.rogers.com/charles.eidsness/au1000_gpio.h
>> 
>> Cheers,
>> Charles
>> 
>> Gilad Rom wrote:
>> > Thanks. Can't I just mmap /dev/mem and use the
>> > GPIO offset from SYS_BASE?
>> > 
>> > Gilad.
>> > 
>> > ----- Original Message ----- From: "Pete Popov"
>> <ppopov@embeddedalley.com>
>> > To: "Gilad Rom" <gilad@romat.com>;
>> <linux-mips@linux-mips.org>
>> > Sent: Friday, November 12, 2004 8:13 PM
>> > Subject: Re: GPIO on the Au1500
>> > 
>> > 
>> >>
>> >> --- Gilad Rom <gilad@romat.com> wrote:
>> >>
>> >>> Hello,
>> >>>
>> >>> I am trying to use the au1000_gpio driver, but
>> I'm a
>> >>> little clueless as to how it is meant to be
>> used. Can I use the GPIO 
>> >>> ioctl's from a userland program, or must I write
>> a kernel module?
>> >>
>> >>
>> >> I'll see if I can dig up some docs and the
>> example
>> >> userland program this weekend. That driver hasn't
>> been
>> >> tested in a while though.
>> >>
>> >> Pete
>> >>
>> >>> Thank you,
>> >>> Gilad Rom
>> >>> Romat Telecom
>> >>>
>> >>>
>> >>>
>> >>
>> > 
>> > 
>> > 
>> 
>> 
> 
>

Re: GPIO on the Au1500

[Charles Eidsness]

Hi Gilad,

I'd be really surprised if it's possible. I think that those addresses 
are beyond the valid physical address range for the mem driver. Even if 
it did work I personally wouldn't feel comfortable doing that sort of 
thing. You could inadvertently cause a lot of nasty things to happen. 
Maybe someone else has a different (better) opinion.

If you do use my driver I uploaded the wrong header file yesterday. I've 
now uploaded the correct one.

Cheers,
Charles

Gilad Rom wrote:
> Thank you for the driver, I'm using it as a reference.
> 
> Still, I am trying to acccess the GPIO ports of the Au1500
> using /dev/mem, but I keep getting these odd values
> (see previous messages to this list)
> 
> Do you think it is possible, or should I stick to using the driver?
> 
> 
> Thank you,
> Gilad.
> 
> ----- Original Message ----- From: "Pete Popov" <ppopov@embeddedalley.com>
> To: <charles.eidsness@ieee.org>; "Gilad Rom" <gilad@romat.com>
> Cc: <linux-mips@linux-mips.org>
> Sent: Sunday, November 14, 2004 8:45 PM
> Subject: Re: GPIO on the Au1500
> 
> 
>>
>> --- Charles Eidsness <charles.eidsness@ieee.org>
>> wrote:
>>
>>> Hi Gilad,
>>>
>>> A little while ago I wrote my own GPIO driver for
>>> the Au1000, mainly as a learning experience. I never bothered to 
>>> release it because a driver already exists and I thought it was working. 
>>
>>
>> It was, a long time ago, when it was written for the
>> Au1000. I had a user app and doc somewhere but can't
>> find it anymore. The driver didn't support gpio2 and
>> was, in general, stale. So perhaps your driver will
>> help Gilad.
>>
>> Pete
>>
>>> I'm not sure if it will work on the Au1550, but if you're interested 
>>> you can
>>> find the source code here:
>>>
>>>
>> http://members.rogers.com/charles.eidsness/au1000_gpio.c
>>
>>>
>> http://members.rogers.com/charles.eidsness/au1000_gpio.h
>>
>>>
>>> Cheers,
>>> Charles
>>>
>>> Gilad Rom wrote:
>>> > Thanks. Can't I just mmap /dev/mem and use the
>>> > GPIO offset from SYS_BASE?
>>> > > Gilad.
>>> > > ----- Original Message ----- From: "Pete Popov"
>>> <ppopov@embeddedalley.com>
>>> > To: "Gilad Rom" <gilad@romat.com>;
>>> <linux-mips@linux-mips.org>
>>> > Sent: Friday, November 12, 2004 8:13 PM
>>> > Subject: Re: GPIO on the Au1500
>>> > > >>
>>> >> --- Gilad Rom <gilad@romat.com> wrote:
>>> >>
>>> >>> Hello,
>>> >>>
>>> >>> I am trying to use the au1000_gpio driver, but
>>> I'm a
>>> >>> little clueless as to how it is meant to be
>>> used. Can I use the GPIO >>> ioctl's from a userland program, or must 
>>> I write
>>> a kernel module?
>>> >>
>>> >>
>>> >> I'll see if I can dig up some docs and the
>>> example
>>> >> userland program this weekend. That driver hasn't
>>> been
>>> >> tested in a while though.
>>> >>
>>> >> Pete
>>> >>
>>> >>> Thank you,
>>> >>> Gilad Rom
>>> >>> Romat Telecom
>>> >>>
>>> >>>
>>> >>>
>>> >>
>>> > > >
>>>
>>
>>
> 
> 
> 

Re: GPIO on the Au1500

[Gilad Rom]

Thanks Charles.

First of all, I managed to get it working today,
(mmapping /dev/mem) so it is possible ;)

Secondly, I am using the GPIO ports for our own custom
design, so I am not exposing /dev/mem to all kinds
of nasty userland apps.

Gilad.

----- Original Message ----- 
From: "Charles Eidsness" <charles.eidsness@ieee.org>
To: "Gilad Rom" <gilad@romat.com>
Cc: <linux-mips@linux-mips.org>
Sent: Monday, November 15, 2004 6:17 PM
Subject: Re: GPIO on the Au1500


> Hi Gilad,
>
> I'd be really surprised if it's possible. I think that those addresses are 
> beyond the valid physical address range for the mem driver. Even if it did 
> work I personally wouldn't feel comfortable doing that sort of thing. You 
> could inadvertently cause a lot of nasty things to happen. Maybe someone 
> else has a different (better) opinion.
>
> If you do use my driver I uploaded the wrong header file yesterday. I've 
> now uploaded the correct one.
>
> Cheers,
> Charles
>
> Gilad Rom wrote:
>> Thank you for the driver, I'm using it as a reference.
>>
>> Still, I am trying to acccess the GPIO ports of the Au1500
>> using /dev/mem, but I keep getting these odd values
>> (see previous messages to this list)
>>
>> Do you think it is possible, or should I stick to using the driver?
>>
>>
>> Thank you,
>> Gilad.
>>
>> ----- Original Message ----- From: "Pete Popov" 
>> <ppopov@embeddedalley.com>
>> To: <charles.eidsness@ieee.org>; "Gilad Rom" <gilad@romat.com>
>> Cc: <linux-mips@linux-mips.org>
>> Sent: Sunday, November 14, 2004 8:45 PM
>> Subject: Re: GPIO on the Au1500
>>
>>
>>>
>>> --- Charles Eidsness <charles.eidsness@ieee.org>
>>> wrote:
>>>
>>>> Hi Gilad,
>>>>
>>>> A little while ago I wrote my own GPIO driver for
>>>> the Au1000, mainly as a learning experience. I never bothered to 
>>>> release it because a driver already exists and I thought it was 
>>>> working.
>>>
>>>
>>> It was, a long time ago, when it was written for the
>>> Au1000. I had a user app and doc somewhere but can't
>>> find it anymore. The driver didn't support gpio2 and
>>> was, in general, stale. So perhaps your driver will
>>> help Gilad.
>>>
>>> Pete
>>>
>>>> I'm not sure if it will work on the Au1550, but if you're interested 
>>>> you can
>>>> find the source code here:
>>>>
>>>>
>>> http://members.rogers.com/charles.eidsness/au1000_gpio.c
>>>
>>>>
>>> http://members.rogers.com/charles.eidsness/au1000_gpio.h
>>>
>>>>
>>>> Cheers,
>>>> Charles
>>>>
>>>> Gilad Rom wrote:
>>>> > Thanks. Can't I just mmap /dev/mem and use the
>>>> > GPIO offset from SYS_BASE?
>>>> > > Gilad.
>>>> > > ----- Original Message ----- From: "Pete Popov"
>>>> <ppopov@embeddedalley.com>
>>>> > To: "Gilad Rom" <gilad@romat.com>;
>>>> <linux-mips@linux-mips.org>
>>>> > Sent: Friday, November 12, 2004 8:13 PM
>>>> > Subject: Re: GPIO on the Au1500
>>>> > > >>
>>>> >> --- Gilad Rom <gilad@romat.com> wrote:
>>>> >>
>>>> >>> Hello,
>>>> >>>
>>>> >>> I am trying to use the au1000_gpio driver, but
>>>> I'm a
>>>> >>> little clueless as to how it is meant to be
>>>> used. Can I use the GPIO >>> ioctl's from a userland program, or must I 
>>>> write
>>>> a kernel module?
>>>> >>
>>>> >>
>>>> >> I'll see if I can dig up some docs and the
>>>> example
>>>> >> userland program this weekend. That driver hasn't
>>>> been
>>>> >> tested in a while though.
>>>> >>
>>>> >> Pete
>>>> >>
>>>> >>> Thank you,
>>>> >>> Gilad Rom
>>>> >>> Romat Telecom
>>>> >>>
>>>> >>>
>>>> >>>
>>>> >>
>>>> > > >
>>>>
>>>
>>>
>>
>> 

Re: GPIO on the Au1500

[Gilad Rom]

Thanks Charles.

First of all, I managed to get it working today,
(mmapping /dev/mem) so it is possible ;)

Secondly, I am using the GPIO ports for our own custom
design, so I am not exposing /dev/mem to all kinds
of nasty userland apps.

Gilad.

----- Original Message ----- 
From: "Charles Eidsness" <charles.eidsness@ieee.org>
To: "Gilad Rom" <gilad@romat.com>
Cc: <linux-mips@linux-mips.org>
Sent: Monday, November 15, 2004 6:17 PM
Subject: Re: GPIO on the Au1500


> Hi Gilad,
>
> I'd be really surprised if it's possible. I think that those addresses are 
> beyond the valid physical address range for the mem driver. Even if it did 
> work I personally wouldn't feel comfortable doing that sort of thing. You 
> could inadvertently cause a lot of nasty things to happen. Maybe someone 
> else has a different (better) opinion.
>
> If you do use my driver I uploaded the wrong header file yesterday. I've 
> now uploaded the correct one.
>
> Cheers,
> Charles
>
> Gilad Rom wrote:
>> Thank you for the driver, I'm using it as a reference.
>>
>> Still, I am trying to acccess the GPIO ports of the Au1500
>> using /dev/mem, but I keep getting these odd values
>> (see previous messages to this list)
>>
>> Do you think it is possible, or should I stick to using the driver?
>>
>>
>> Thank you,
>> Gilad.
>>
>> ----- Original Message ----- From: "Pete Popov" 
>> <ppopov@embeddedalley.com>
>> To: <charles.eidsness@ieee.org>; "Gilad Rom" <gilad@romat.com>
>> Cc: <linux-mips@linux-mips.org>
>> Sent: Sunday, November 14, 2004 8:45 PM
>> Subject: Re: GPIO on the Au1500
>>
>>
>>>
>>> --- Charles Eidsness <charles.eidsness@ieee.org>
>>> wrote:
>>>
>>>> Hi Gilad,
>>>>
>>>> A little while ago I wrote my own GPIO driver for
>>>> the Au1000, mainly as a learning experience. I never bothered to 
>>>> release it because a driver already exists and I thought it was 
>>>> working.
>>>
>>>
>>> It was, a long time ago, when it was written for the
>>> Au1000. I had a user app and doc somewhere but can't
>>> find it anymore. The driver didn't support gpio2 and
>>> was, in general, stale. So perhaps your driver will
>>> help Gilad.
>>>
>>> Pete
>>>
>>>> I'm not sure if it will work on the Au1550, but if you're interested 
>>>> you can
>>>> find the source code here:
>>>>
>>>>
>>> http://members.rogers.com/charles.eidsness/au1000_gpio.c
>>>
>>>>
>>> http://members.rogers.com/charles.eidsness/au1000_gpio.h
>>>
>>>>
>>>> Cheers,
>>>> Charles
>>>>
>>>> Gilad Rom wrote:
>>>> > Thanks. Can't I just mmap /dev/mem and use the
>>>> > GPIO offset from SYS_BASE?
>>>> > > Gilad.
>>>> > > ----- Original Message ----- From: "Pete Popov"
>>>> <ppopov@embeddedalley.com>
>>>> > To: "Gilad Rom" <gilad@romat.com>;
>>>> <linux-mips@linux-mips.org>
>>>> > Sent: Friday, November 12, 2004 8:13 PM
>>>> > Subject: Re: GPIO on the Au1500
>>>> > > >>
>>>> >> --- Gilad Rom <gilad@romat.com> wrote:
>>>> >>
>>>> >>> Hello,
>>>> >>>
>>>> >>> I am trying to use the au1000_gpio driver, but
>>>> I'm a
>>>> >>> little clueless as to how it is meant to be
>>>> used. Can I use the GPIO >>> ioctl's from a userland program, or must I 
>>>> write
>>>> a kernel module?
>>>> >>
>>>> >>
>>>> >> I'll see if I can dig up some docs and the
>>>> example
>>>> >> userland program this weekend. That driver hasn't
>>>> been
>>>> >> tested in a while though.
>>>> >>
>>>> >> Pete
>>>> >>
>>>> >>> Thank you,
>>>> >>> Gilad Rom
>>>> >>> Romat Telecom
>>>> >>>
>>>> >>>
>>>> >>>
>>>> >>
>>>> > > >
>>>>
>>>
>>>
>>
>> 

Re: GPIO on the Au1500

[Dan Malek]

On Nov 14, 2004, at 10:53 AM, Gilad Rom wrote:

> For some reason, I keep getting that magical value, 0x10000001 for 
> EVERY address I try to read, be it SYS_BASE (0xB1900000) or every 
> other address.

It's not working because that is not the address of the device(s).
The 0xB1900000 is the Kernel Virtual address of these devices, the real
physical address, and the one you have to use with mmap() is the
system control block address 0x11900000.

Just be very, very careful with user space access of any IO using this
method.  The kernel can ensure atomic updates using various methods,
but user applications can't and may cause system failures.  This is why
a GPIO driver is a much better approach.

	-- Dan

Re: GPIO on the Au1500

[Dan Malek]

On Nov 14, 2004, at 10:53 AM, Gilad Rom wrote:

> For some reason, I keep getting that magical value, 0x10000001 for 
> EVERY address I try to read, be it SYS_BASE (0xB1900000) or every 
> other address.

It's not working because that is not the address of the device(s).
The 0xB1900000 is the Kernel Virtual address of these devices, the real
physical address, and the one you have to use with mmap() is the
system control block address 0x11900000.

Just be very, very careful with user space access of any IO using this
method.  The kernel can ensure atomic updates using various methods,
but user applications can't and may cause system failures.  This is why
a GPIO driver is a much better approach.

	-- Dan