[dwi2c PATCH v1] dwi2c add offsets to reads

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[dwi2c PATCH v1] dwi2c add offsets to reads

cduffinx
modify the designware_i2c_xfer function to use 1 byte per
address, it was set to 0 before which makes it think its
reading a register type. Added offset of where it is
supposed to read from. Before it was always reading from
offset 0 despite specifying the offset in the higher level
function.

Signed-off-by: Cooper Duffin <[hidden email]>
Signed-off-by: cduffinx <[hidden email]>
---

 drivers/i2c/designware_i2c.c | 5 +++--
 drivers/i2c/i2c-uclass.c     | 1 +
 include/i2c.h                | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
index 0b5e70af59..46f5d1e56c 100644
--- a/drivers/i2c/designware_i2c.c
+++ b/drivers/i2c/designware_i2c.c
@@ -658,8 +658,9 @@ static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
  for (; nmsgs > 0; nmsgs--, msg++) {
  debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
  if (msg->flags & I2C_M_RD) {
- ret = __dw_i2c_read(i2c->regs, msg->addr, 0, 0,
-    msg->buf, msg->len);
+ ret = __dw_i2c_read(i2c->regs, msg->addr,
+    msg->offset, 1, msg->buf,
+    msg->len);
  } else {
  ret = __dw_i2c_write(i2c->regs, msg->addr, 0, 0,
      msg->buf, msg->len);
diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c
index 2aa3efe8aa..455d56c3b8 100644
--- a/drivers/i2c/i2c-uclass.c
+++ b/drivers/i2c/i2c-uclass.c
@@ -147,6 +147,7 @@ int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len)
  ptr->flags |= I2C_M_RD;
  ptr->len = len;
  ptr->buf = buffer;
+ ptr->offset = offset;
  ptr++;
  }
  msg_count = ptr - msg;
diff --git a/include/i2c.h b/include/i2c.h
index 0faf8542e2..f997c2537e 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -141,6 +141,7 @@ struct i2c_msg {
  uint addr;
  uint flags;
  uint len;
+ uint offset;
  u8 *buf;
 };
 
--
2.25.1

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Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Simon Glass-3
Hi Cduffinx,

On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:

>
> modify the designware_i2c_xfer function to use 1 byte per
> address, it was set to 0 before which makes it think its
> reading a register type. Added offset of where it is
> supposed to read from. Before it was always reading from
> offset 0 despite specifying the offset in the higher level
> function.
>
> Signed-off-by: Cooper Duffin <[hidden email]>
> Signed-off-by: cduffinx <[hidden email]>
> ---
>
>  drivers/i2c/designware_i2c.c | 5 +++--
>  drivers/i2c/i2c-uclass.c     | 1 +
>  include/i2c.h                | 1 +
>  3 files changed, 5 insertions(+), 2 deletions(-)
>

Thanks for the patch!

Is there a test that was failing before (test/dm/i2c.c) or should we
add a new one to catch this?

Regards,
Simon
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RE: [dwi2c PATCH v1] dwi2c add offsets to reads

cduffinx
Hello Simon,

I wasn’t using the test/dm/i2c I this was tested using hardware where I was using the dm_i2c_read() function. I just tried to use the test/dm/i2c where I am following the README but I keep getting  "sdl2-config: Command not found". I suspect it would also fail where it is trying to read but I will have to get test/dm/i2c working before I know for sure.

Essentially my test was  

int uboot_app (int argc, char * const argv[])
{
        uint8_t buf[10];
        uint8_t read_buf[5];
        uint8_t dev_addr;
        uint32_t bus_speed;
        //i2c_bus device pointer
        struct udevice *i2c_led;
        struct udevice *bus;
        app_startup(argv);
        /* Print the ABI version */
        printf ("Example expects ABI version %d\n", XF_VERSION);
        printf ("Actual U-Boot ABI version %d\n", (int)get_version());

        dev_addr = 0x60;
        bus_speed = 100000; //100KHz
        printf("starting test i2c\n");
        buf[0] = 'b';
        buf[1] = 'o';
        buf[2] = 'o';
        buf[3] = 't';
        //Get i2c chip, init the code
        printf("init starting\n");
        if(i2c_get_chip_for_busnum(0 , 0x60, 1, &i2c_led)!=0){
                printf("ERROR: no device found at %x \n",dev_addr);
                return (0);
        }
        uclass_get_device_by_seq(UCLASS_I2C, 0, &bus);
        printf("Setting bus speed to %d\n", bus_speed);
        if(dm_i2c_set_bus_speed(bus,bus_speed)!=0){
                printf("ERROR: Cannot set buspeed\n");
                return (0);
        }
        printf("i2c_led name is %s\n",i2c_led->name);
        if(i2c_led == NULL){
                printf("ERROR i2c_led 0 is null\n");
                return (0);
        }
        printf("Writing\n");
        for(unsigned int a =0; a< 4; a++){
                if(dm_i2c_write(i2c_led,a,&buf[a],1)!=0){
                        printf("ERROR writing\n");
                        return (0);
                }
        }
       
        printf("Reading\n");
        for(unsigned int a =0; a< 4; a++){
                if(dm_i2c_read(i2c_led,a,&read_buf[a],1)!=0){
                        printf("ERROR writing\n");
                        return (0);
                }
        }
        printf("read buffer is %c, %c, %c, %c \n",read_buf[0],read_buf[1], read_buf[2],read_buf[3]);
        printf ("\n\n");
        return (0);
}

## Starting application at 0x0C100000 ...
Example expects ABI version 10
Actual U-Boot ABI version 10
starting test i2c
init starting
Setting bus speed to 100000
i2c_led name is generic_60
Writing
Reading
read buffer is o, o, o, o
 
with the fix I get:

## Starting application at 0x0C100000 ...
Example expects ABI version 10
Actual U-Boot ABI version 10
starting test i2c
init starting
Setting bus speed to 100000
i2c_led name is generic_60
Writing
Reading
read buffer is b, o, o, t

which is correct. Similarly if I stop auto boot I get a similar result:

Hit any key to stop autoboot:  0
device # i2c
i2c - I2C sub-system

Assuming I write "boot" to the device
device # i2c dev 0
Setting bus to 0
device # i2c md 0x60 0 4
0000: 6f 6f 6f 6f    oooo

With the fix/patch I get:
 
device# i2c md 0x60 0 4
0000: 62 6f 6f 74    boot

Which is correct. Also the reads were working in linux leading to my original suspicion that there might be something going on in the driver. Hopefully that answers your question let me know if you have anymore.

Best regards,

-Cooper Duffin
-----Original Message-----
From: Simon Glass <[hidden email]>
Sent: Friday, November 6, 2020 10:51 AM
To: Duffin, CooperX <[hidden email]>
Cc: U-Boot Mailing List <[hidden email]>; [hidden email]; Tom Rini <[hidden email]>; Robert Beckett <[hidden email]>; Heiko Schocher <[hidden email]>; Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Hi Cduffinx,

On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:

>
> modify the designware_i2c_xfer function to use 1 byte per address, it
> was set to 0 before which makes it think its reading a register type.
> Added offset of where it is supposed to read from. Before it was
> always reading from offset 0 despite specifying the offset in the
> higher level function.
>
> Signed-off-by: Cooper Duffin <[hidden email]>
> Signed-off-by: cduffinx <[hidden email]>
> ---
>
>  drivers/i2c/designware_i2c.c | 5 +++--
>  drivers/i2c/i2c-uclass.c     | 1 +
>  include/i2c.h                | 1 +
>  3 files changed, 5 insertions(+), 2 deletions(-)
>

Thanks for the patch!

Is there a test that was failing before (test/dm/i2c.c) or should we add a new one to catch this?

Regards,
Simon
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Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Simon Glass-3
Hi CooperX,

On Fri, 6 Nov 2020 at 16:08, Duffin, CooperX <[hidden email]> wrote:

>
> Hello Simon,
>
> I wasn’t using the test/dm/i2c I this was tested using hardware where I was using the dm_i2c_read() function. I just tried to use the test/dm/i2c where I am following the README but I keep getting  "sdl2-config: Command not found". I suspect it would also fail where it is trying to read but I will have to get test/dm/i2c working before I know for sure.
>
> Essentially my test was
>
> int uboot_app (int argc, char * const argv[])
> {
>         uint8_t buf[10];
>         uint8_t read_buf[5];
>         uint8_t dev_addr;
>         uint32_t bus_speed;
>         //i2c_bus device pointer
>         struct udevice *i2c_led;
>         struct udevice *bus;
>         app_startup(argv);
>         /* Print the ABI version */
>         printf ("Example expects ABI version %d\n", XF_VERSION);
>         printf ("Actual U-Boot ABI version %d\n", (int)get_version());
>
>         dev_addr = 0x60;
>         bus_speed = 100000; //100KHz
>         printf("starting test i2c\n");
>         buf[0] = 'b';
>         buf[1] = 'o';
>         buf[2] = 'o';
>         buf[3] = 't';
>         //Get i2c chip, init the code
>         printf("init starting\n");
>         if(i2c_get_chip_for_busnum(0 , 0x60, 1, &i2c_led)!=0){
>                 printf("ERROR: no device found at %x \n",dev_addr);
>                 return (0);
>         }
>         uclass_get_device_by_seq(UCLASS_I2C, 0, &bus);
>         printf("Setting bus speed to %d\n", bus_speed);
>         if(dm_i2c_set_bus_speed(bus,bus_speed)!=0){
>                 printf("ERROR: Cannot set buspeed\n");
>                 return (0);
>         }
>         printf("i2c_led name is %s\n",i2c_led->name);
>         if(i2c_led == NULL){
>                 printf("ERROR i2c_led 0 is null\n");
>                 return (0);
>         }
>         printf("Writing\n");
>         for(unsigned int a =0; a< 4; a++){
>                 if(dm_i2c_write(i2c_led,a,&buf[a],1)!=0){
>                         printf("ERROR writing\n");
>                         return (0);
>                 }
>         }
>
>         printf("Reading\n");
>         for(unsigned int a =0; a< 4; a++){
>                 if(dm_i2c_read(i2c_led,a,&read_buf[a],1)!=0){
>                         printf("ERROR writing\n");
>                         return (0);
>                 }
>         }
>         printf("read buffer is %c, %c, %c, %c \n",read_buf[0],read_buf[1], read_buf[2],read_buf[3]);
>         printf ("\n\n");
>         return (0);
> }
>
> ## Starting application at 0x0C100000 ...
> Example expects ABI version 10
> Actual U-Boot ABI version 10
> starting test i2c
> init starting
> Setting bus speed to 100000
> i2c_led name is generic_60
> Writing
> Reading
> read buffer is o, o, o, o
>
> with the fix I get:
>
> ## Starting application at 0x0C100000 ...
> Example expects ABI version 10
> Actual U-Boot ABI version 10
> starting test i2c
> init starting
> Setting bus speed to 100000
> i2c_led name is generic_60
> Writing
> Reading
> read buffer is b, o, o, t
>
> which is correct. Similarly if I stop auto boot I get a similar result:
>
> Hit any key to stop autoboot:  0
> device # i2c
> i2c - I2C sub-system
>
> Assuming I write "boot" to the device
> device # i2c dev 0
> Setting bus to 0
> device # i2c md 0x60 0 4
> 0000: 6f 6f 6f 6f    oooo
>
> With the fix/patch I get:
>
> device# i2c md 0x60 0 4
> 0000: 62 6f 6f 74    boot
>
> Which is correct. Also the reads were working in linux leading to my original suspicion that there might be something going on in the driver. Hopefully that answers your question let me know if you have anymore.

I had a bit of a look at this. If you look at dm_i2c_read() it
actually builds the address into the buffer it sends. So when it gets
to __dw_i2c_write() the alen parameter is always 0. That function is
actually a holdover from before driver model, so one day the alen and
addr parameters will go away.

I wonder if your device does not support multiple-byte reads or
writes? Can you try the i2c md with a single byte? There is a
DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
command.

In the designware_i2c_xfer(), try printing out the bytes that it gets
in each message using i2c_dump_msgs().

Also check the i2c_get_chip() function which you are using. See if
chip->offset_len is set to 1 as it should be, for your device. If not,
perhaps something is missing.

In short I am not really sure what is going on, but I think it needs
more investigation.

BTW with this mailing list we like people to reply inline or at the
bottom, not at the top.

Regards,
Simon

>
> Best regards,
>
> -Cooper Duffin
> -----Original Message-----
> From: Simon Glass <[hidden email]>
> Sent: Friday, November 6, 2020 10:51 AM
> To: Duffin, CooperX <[hidden email]>
> Cc: U-Boot Mailing List <[hidden email]>; [hidden email]; Tom Rini <[hidden email]>; Robert Beckett <[hidden email]>; Heiko Schocher <[hidden email]>; Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
> Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
>
> Hi Cduffinx,
>
> On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:
> >
> > modify the designware_i2c_xfer function to use 1 byte per address, it
> > was set to 0 before which makes it think its reading a register type.
> > Added offset of where it is supposed to read from. Before it was
> > always reading from offset 0 despite specifying the offset in the
> > higher level function.
> >
> > Signed-off-by: Cooper Duffin <[hidden email]>
> > Signed-off-by: cduffinx <[hidden email]>
> > ---
> >
> >  drivers/i2c/designware_i2c.c | 5 +++--
> >  drivers/i2c/i2c-uclass.c     | 1 +
> >  include/i2c.h                | 1 +
> >  3 files changed, 5 insertions(+), 2 deletions(-)
> >
>
> Thanks for the patch!
>
> Is there a test that was failing before (test/dm/i2c.c) or should we add a new one to catch this?
>
> Regards,
> Simon
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RE: [dwi2c PATCH v1] dwi2c add offsets to reads

cduffinx
-----Original Message-----
From: Simon Glass <[hidden email]>
Sent: Saturday, November 7, 2020 1:33 PM
To: Duffin, CooperX <[hidden email]>
Cc: U-Boot Mailing List <[hidden email]>; [hidden email]; Tom Rini <[hidden email]>; Robert Beckett <[hidden email]>; Heiko Schocher <[hidden email]>; Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Hi CooperX,

On Fri, 6 Nov 2020 at 16:08, Duffin, CooperX <[hidden email]> wrote:

>
> Hello Simon,
>
> I wasn’t using the test/dm/i2c I this was tested using hardware where I was using the dm_i2c_read() function. I just tried to use the test/dm/i2c where I am following the README but I keep getting  "sdl2-config: Command not found". I suspect it would also fail where it is trying to read but I will have to get test/dm/i2c working before I know for sure.
>
> Essentially my test was
>
> int uboot_app (int argc, char * const argv[]) {
>         uint8_t buf[10];
>         uint8_t read_buf[5];
>         uint8_t dev_addr;
>         uint32_t bus_speed;
>         //i2c_bus device pointer
>         struct udevice *i2c_led;
>         struct udevice *bus;
>         app_startup(argv);
>         /* Print the ABI version */
>         printf ("Example expects ABI version %d\n", XF_VERSION);
>         printf ("Actual U-Boot ABI version %d\n", (int)get_version());
>
>         dev_addr = 0x60;
>         bus_speed = 100000; //100KHz
>         printf("starting test i2c\n");
>         buf[0] = 'b';
>         buf[1] = 'o';
>         buf[2] = 'o';
>         buf[3] = 't';
>         //Get i2c chip, init the code
>         printf("init starting\n");
>         if(i2c_get_chip_for_busnum(0 , 0x60, 1, &i2c_led)!=0){
>                 printf("ERROR: no device found at %x \n",dev_addr);
>                 return (0);
>         }
>         uclass_get_device_by_seq(UCLASS_I2C, 0, &bus);
>         printf("Setting bus speed to %d\n", bus_speed);
>         if(dm_i2c_set_bus_speed(bus,bus_speed)!=0){
>                 printf("ERROR: Cannot set buspeed\n");
>                 return (0);
>         }
>         printf("i2c_led name is %s\n",i2c_led->name);
>         if(i2c_led == NULL){
>                 printf("ERROR i2c_led 0 is null\n");
>                 return (0);
>         }
>         printf("Writing\n");
>         for(unsigned int a =0; a< 4; a++){
>                 if(dm_i2c_write(i2c_led,a,&buf[a],1)!=0){
>                         printf("ERROR writing\n");
>                         return (0);
>                 }
>         }
>
>         printf("Reading\n");
>         for(unsigned int a =0; a< 4; a++){
>                 if(dm_i2c_read(i2c_led,a,&read_buf[a],1)!=0){
>                         printf("ERROR writing\n");
>                         return (0);
>                 }
>         }
>         printf("read buffer is %c, %c, %c, %c \n",read_buf[0],read_buf[1], read_buf[2],read_buf[3]);
>         printf ("\n\n");
>         return (0);
> }
>
> ## Starting application at 0x0C100000 ...
> Example expects ABI version 10
> Actual U-Boot ABI version 10
> starting test i2c
> init starting
> Setting bus speed to 100000
> i2c_led name is generic_60
> Writing
> Reading
> read buffer is o, o, o, o
>
> with the fix I get:
>
> ## Starting application at 0x0C100000 ...
> Example expects ABI version 10
> Actual U-Boot ABI version 10
> starting test i2c
> init starting
> Setting bus speed to 100000
> i2c_led name is generic_60
> Writing
> Reading
> read buffer is b, o, o, t
>
> which is correct. Similarly if I stop auto boot I get a similar result:
>
> Hit any key to stop autoboot:  0
> device # i2c
> i2c - I2C sub-system
>
> Assuming I write "boot" to the device
> device # i2c dev 0
> Setting bus to 0
> device # i2c md 0x60 0 4
> 0000: 6f 6f 6f 6f    oooo
>
> With the fix/patch I get:
>
> device# i2c md 0x60 0 4
> 0000: 62 6f 6f 74    boot
>
> Which is correct. Also the reads were working in linux leading to my original suspicion that there might be something going on in the driver. Hopefully that answers your question let me know if you have anymore.

I had a bit of a look at this. If you look at dm_i2c_read() it actually builds the address into the buffer it sends. So when it gets to __dw_i2c_write() the alen parameter is always 0. That function is actually a holdover from before driver model, so one day the alen and addr parameters will go away.

I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
command.

In the designware_i2c_xfer(), try printing out the bytes that it gets in each message using i2c_dump_msgs().

Also check the i2c_get_chip() function which you are using. See if
chip->offset_len is set to 1 as it should be, for your device. If not,
perhaps something is missing.

In short I am not really sure what is going on, but I think it needs more investigation.

BTW with this mailing list we like people to reply inline or at the bottom, not at the top.

Regards,
Simon

>
> Best regards,
>
> -Cooper Duffin
> -----Original Message-----
> From: Simon Glass <[hidden email]>
> Sent: Friday, November 6, 2020 10:51 AM
> To: Duffin, CooperX <[hidden email]>
> Cc: U-Boot Mailing List <[hidden email]>;
> [hidden email]; Tom Rini <[hidden email]>; Robert
> Beckett <[hidden email]>; Heiko Schocher <[hidden email]>;
> Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
> Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
>
> Hi Cduffinx,
>
> On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:
> >
> > modify the designware_i2c_xfer function to use 1 byte per address,
> > it was set to 0 before which makes it think its reading a register type.
> > Added offset of where it is supposed to read from. Before it was
> > always reading from offset 0 despite specifying the offset in the
> > higher level function.
> >
> > Signed-off-by: Cooper Duffin <[hidden email]>
> > Signed-off-by: cduffinx <[hidden email]>
> > ---
> >
> >  drivers/i2c/designware_i2c.c | 5 +++--
> >  drivers/i2c/i2c-uclass.c     | 1 +
> >  include/i2c.h                | 1 +
> >  3 files changed, 5 insertions(+), 2 deletions(-)
> >
>
> Thanks for the patch!
>
> Is there a test that was failing before (test/dm/i2c.c) or should we add a new one to catch this?
>
> Regards,
> Simon

[Duffin, CooperX]
Thanks for the reply Simon.  I tried a couple more things.

Simon Glass <[hidden email]> wrote:
> I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
>command.

I tried with the flag DM_I2C_CHIP_WR_ADDRESS but it did not make a difference. A single byte read will yield the following:

Device # i2c md 0x60 0 1
0000: 6f    o

Which is not correct in fact it doesn’t seem to matter how much I read it only picks up the second character I wrote to it. For example if I read 16 characters I get:
device# i2c flags 0x60 4
device # i2c md 0x60 0 10
0000: 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f    oooooooooooooooo

I can tell the writes are working because I am writing to an LED display and I can see the proper characters get displayed. Also I think my i2c device needs restarts in-between each byte for it to work properly, so I need to be able to read individual bytes with there corresponding offsets, also i2c-tools supports this.

Simon Glass <[hidden email]> wrote:
>Also check the i2c_get_chip() function which you are using. See if
>chip->offset_len is set to 1 as it should be, for your device. If not,
>perhaps something is missing.
If I use this command I get:

device # i2c olen 0x60
1

This is  without the patch BTW.
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Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Simon Glass-3
+Heiko Schocher who might know more about this I2C question

On Mon, 9 Nov 2020 at 15:09, Duffin, CooperX <[hidden email]> wrote:

>
> -----Original Message-----
> From: Simon Glass <[hidden email]>
> Sent: Saturday, November 7, 2020 1:33 PM
> To: Duffin, CooperX <[hidden email]>
> Cc: U-Boot Mailing List <[hidden email]>; [hidden email]; Tom Rini <[hidden email]>; Robert Beckett <[hidden email]>; Heiko Schocher <[hidden email]>; Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
> Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
>
> Hi CooperX,
>
> On Fri, 6 Nov 2020 at 16:08, Duffin, CooperX <[hidden email]> wrote:
> >
> > Hello Simon,
> >
> > I wasn’t using the test/dm/i2c I this was tested using hardware where I was using the dm_i2c_read() function. I just tried to use the test/dm/i2c where I am following the README but I keep getting  "sdl2-config: Command not found". I suspect it would also fail where it is trying to read but I will have to get test/dm/i2c working before I know for sure.
> >
> > Essentially my test was
> >
> > int uboot_app (int argc, char * const argv[]) {
> >         uint8_t buf[10];
> >         uint8_t read_buf[5];
> >         uint8_t dev_addr;
> >         uint32_t bus_speed;
> >         //i2c_bus device pointer
> >         struct udevice *i2c_led;
> >         struct udevice *bus;
> >         app_startup(argv);
> >         /* Print the ABI version */
> >         printf ("Example expects ABI version %d\n", XF_VERSION);
> >         printf ("Actual U-Boot ABI version %d\n", (int)get_version());
> >
> >         dev_addr = 0x60;
> >         bus_speed = 100000; //100KHz
> >         printf("starting test i2c\n");
> >         buf[0] = 'b';
> >         buf[1] = 'o';
> >         buf[2] = 'o';
> >         buf[3] = 't';
> >         //Get i2c chip, init the code
> >         printf("init starting\n");
> >         if(i2c_get_chip_for_busnum(0 , 0x60, 1, &i2c_led)!=0){
> >                 printf("ERROR: no device found at %x \n",dev_addr);
> >                 return (0);
> >         }
> >         uclass_get_device_by_seq(UCLASS_I2C, 0, &bus);
> >         printf("Setting bus speed to %d\n", bus_speed);
> >         if(dm_i2c_set_bus_speed(bus,bus_speed)!=0){
> >                 printf("ERROR: Cannot set buspeed\n");
> >                 return (0);
> >         }
> >         printf("i2c_led name is %s\n",i2c_led->name);
> >         if(i2c_led == NULL){
> >                 printf("ERROR i2c_led 0 is null\n");
> >                 return (0);
> >         }
> >         printf("Writing\n");
> >         for(unsigned int a =0; a< 4; a++){
> >                 if(dm_i2c_write(i2c_led,a,&buf[a],1)!=0){
> >                         printf("ERROR writing\n");
> >                         return (0);
> >                 }
> >         }
> >
> >         printf("Reading\n");
> >         for(unsigned int a =0; a< 4; a++){
> >                 if(dm_i2c_read(i2c_led,a,&read_buf[a],1)!=0){
> >                         printf("ERROR writing\n");
> >                         return (0);
> >                 }
> >         }
> >         printf("read buffer is %c, %c, %c, %c \n",read_buf[0],read_buf[1], read_buf[2],read_buf[3]);
> >         printf ("\n\n");
> >         return (0);
> > }
> >
> > ## Starting application at 0x0C100000 ...
> > Example expects ABI version 10
> > Actual U-Boot ABI version 10
> > starting test i2c
> > init starting
> > Setting bus speed to 100000
> > i2c_led name is generic_60
> > Writing
> > Reading
> > read buffer is o, o, o, o
> >
> > with the fix I get:
> >
> > ## Starting application at 0x0C100000 ...
> > Example expects ABI version 10
> > Actual U-Boot ABI version 10
> > starting test i2c
> > init starting
> > Setting bus speed to 100000
> > i2c_led name is generic_60
> > Writing
> > Reading
> > read buffer is b, o, o, t
> >
> > which is correct. Similarly if I stop auto boot I get a similar result:
> >
> > Hit any key to stop autoboot:  0
> > device # i2c
> > i2c - I2C sub-system
> >
> > Assuming I write "boot" to the device
> > device # i2c dev 0
> > Setting bus to 0
> > device # i2c md 0x60 0 4
> > 0000: 6f 6f 6f 6f    oooo
> >
> > With the fix/patch I get:
> >
> > device# i2c md 0x60 0 4
> > 0000: 62 6f 6f 74    boot
> >
> > Which is correct. Also the reads were working in linux leading to my original suspicion that there might be something going on in the driver. Hopefully that answers your question let me know if you have anymore.
>
> I had a bit of a look at this. If you look at dm_i2c_read() it actually builds the address into the buffer it sends. So when it gets to __dw_i2c_write() the alen parameter is always 0. That function is actually a holdover from before driver model, so one day the alen and addr parameters will go away.
>
> I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
> command.
>
> In the designware_i2c_xfer(), try printing out the bytes that it gets in each message using i2c_dump_msgs().
>
> Also check the i2c_get_chip() function which you are using. See if
> chip->offset_len is set to 1 as it should be, for your device. If not,
> perhaps something is missing.
>
> In short I am not really sure what is going on, but I think it needs more investigation.
>
> BTW with this mailing list we like people to reply inline or at the bottom, not at the top.
>
> Regards,
> Simon
>
> >
> > Best regards,
> >
> > -Cooper Duffin
> > -----Original Message-----
> > From: Simon Glass <[hidden email]>
> > Sent: Friday, November 6, 2020 10:51 AM
> > To: Duffin, CooperX <[hidden email]>
> > Cc: U-Boot Mailing List <[hidden email]>;
> > [hidden email]; Tom Rini <[hidden email]>; Robert
> > Beckett <[hidden email]>; Heiko Schocher <[hidden email]>;
> > Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
> > Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
> >
> > Hi Cduffinx,
> >
> > On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:
> > >
> > > modify the designware_i2c_xfer function to use 1 byte per address,
> > > it was set to 0 before which makes it think its reading a register type.
> > > Added offset of where it is supposed to read from. Before it was
> > > always reading from offset 0 despite specifying the offset in the
> > > higher level function.
> > >
> > > Signed-off-by: Cooper Duffin <[hidden email]>
> > > Signed-off-by: cduffinx <[hidden email]>
> > > ---
> > >
> > >  drivers/i2c/designware_i2c.c | 5 +++--
> > >  drivers/i2c/i2c-uclass.c     | 1 +
> > >  include/i2c.h                | 1 +
> > >  3 files changed, 5 insertions(+), 2 deletions(-)
> > >
> >
> > Thanks for the patch!
> >
> > Is there a test that was failing before (test/dm/i2c.c) or should we add a new one to catch this?
> >
> > Regards,
> > Simon
>
> [Duffin, CooperX]
> Thanks for the reply Simon.  I tried a couple more things.
>
> Simon Glass <[hidden email]> wrote:
> > I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
> >command.
>
> I tried with the flag DM_I2C_CHIP_WR_ADDRESS but it did not make a difference. A single byte read will yield the following:
>
> Device # i2c md 0x60 0 1
> 0000: 6f    o
>
> Which is not correct in fact it doesn’t seem to matter how much I read it only picks up the second character I wrote to it. For example if I read 16 characters I get:
> device# i2c flags 0x60 4
> device # i2c md 0x60 0 10
> 0000: 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f    oooooooooooooooo
>
> I can tell the writes are working because I am writing to an LED display and I can see the proper characters get displayed. Also I think my i2c device needs restarts in-between each byte for it to work properly, so I need to be able to read individual bytes with there corresponding offsets, also i2c-tools supports this.
>
> Simon Glass <[hidden email]> wrote:
> >Also check the i2c_get_chip() function which you are using. See if
> >chip->offset_len is set to 1 as it should be, for your device. If not,
> >perhaps something is missing.
> If I use this command I get:
>
> device # i2c olen 0x60
> 1
>
> This is  without the patch BTW.
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Re: [dwi2c PATCH v1] dwi2c add offsets to reads

Heiko Schocher denx
Hello Simon,

Am 17.11.2020 um 00:20 schrieb Simon Glass:
> +Heiko Schocher who might know more about this I2C question

Sorry for late response ...

> On Mon, 9 Nov 2020 at 15:09, Duffin, CooperX <[hidden email]> wrote:
>>
>> -----Original Message-----
>> From: Simon Glass <[hidden email]>
>> Sent: Saturday, November 7, 2020 1:33 PM
>> To: Duffin, CooperX <[hidden email]>
>> Cc: U-Boot Mailing List <[hidden email]>; [hidden email]; Tom Rini <[hidden email]>; Robert Beckett <[hidden email]>; Heiko Schocher <[hidden email]>; Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
>> Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
>>
>> Hi CooperX,
>>
>> On Fri, 6 Nov 2020 at 16:08, Duffin, CooperX <[hidden email]> wrote:
>>>
>>> Hello Simon,
>>>
>>> I wasn’t using the test/dm/i2c I this was tested using hardware where I was using the dm_i2c_read() function. I just tried to use the test/dm/i2c where I am following the README but I keep getting  "sdl2-config: Command not found". I suspect it would also fail where it is trying to read but I will have to get test/dm/i2c working before I know for sure.
>>>
>>> Essentially my test was
>>>
>>> int uboot_app (int argc, char * const argv[]) {
>>>         uint8_t buf[10];
>>>         uint8_t read_buf[5];
>>>         uint8_t dev_addr;
>>>         uint32_t bus_speed;
>>>         //i2c_bus device pointer
>>>         struct udevice *i2c_led;
>>>         struct udevice *bus;
>>>         app_startup(argv);
>>>         /* Print the ABI version */
>>>         printf ("Example expects ABI version %d\n", XF_VERSION);
>>>         printf ("Actual U-Boot ABI version %d\n", (int)get_version());
>>>
>>>         dev_addr = 0x60;
>>>         bus_speed = 100000; //100KHz
>>>         printf("starting test i2c\n");
>>>         buf[0] = 'b';
>>>         buf[1] = 'o';
>>>         buf[2] = 'o';
>>>         buf[3] = 't';
>>>         //Get i2c chip, init the code
>>>         printf("init starting\n");
>>>         if(i2c_get_chip_for_busnum(0 , 0x60, 1, &i2c_led)!=0){
>>>                 printf("ERROR: no device found at %x \n",dev_addr);
>>>                 return (0);
>>>         }
>>>         uclass_get_device_by_seq(UCLASS_I2C, 0, &bus);
>>>         printf("Setting bus speed to %d\n", bus_speed);
>>>         if(dm_i2c_set_bus_speed(bus,bus_speed)!=0){
>>>                 printf("ERROR: Cannot set buspeed\n");
>>>                 return (0);
>>>         }
>>>         printf("i2c_led name is %s\n",i2c_led->name);
>>>         if(i2c_led == NULL){
>>>                 printf("ERROR i2c_led 0 is null\n");
>>>                 return (0);
>>>         }
>>>         printf("Writing\n");
>>>         for(unsigned int a =0; a< 4; a++){
>>>                 if(dm_i2c_write(i2c_led,a,&buf[a],1)!=0){
>>>                         printf("ERROR writing\n");
>>>                         return (0);
>>>                 }
>>>         }
>>>
>>>         printf("Reading\n");
>>>         for(unsigned int a =0; a< 4; a++){
>>>                 if(dm_i2c_read(i2c_led,a,&read_buf[a],1)!=0){
>>>                         printf("ERROR writing\n");
>>>                         return (0);
>>>                 }
>>>         }
>>>         printf("read buffer is %c, %c, %c, %c \n",read_buf[0],read_buf[1], read_buf[2],read_buf[3]);
>>>         printf ("\n\n");
>>>         return (0);
>>> }
>>>
>>> ## Starting application at 0x0C100000 ...
>>> Example expects ABI version 10
>>> Actual U-Boot ABI version 10
>>> starting test i2c
>>> init starting
>>> Setting bus speed to 100000
>>> i2c_led name is generic_60
>>> Writing
>>> Reading
>>> read buffer is o, o, o, o
>>>
>>> with the fix I get:
>>>
>>> ## Starting application at 0x0C100000 ...
>>> Example expects ABI version 10
>>> Actual U-Boot ABI version 10
>>> starting test i2c
>>> init starting
>>> Setting bus speed to 100000
>>> i2c_led name is generic_60
>>> Writing
>>> Reading
>>> read buffer is b, o, o, t
>>>
>>> which is correct. Similarly if I stop auto boot I get a similar result:
>>>
>>> Hit any key to stop autoboot:  0
>>> device # i2c
>>> i2c - I2C sub-system
>>>
>>> Assuming I write "boot" to the device
>>> device # i2c dev 0
>>> Setting bus to 0
>>> device # i2c md 0x60 0 4
>>> 0000: 6f 6f 6f 6f    oooo
>>>
>>> With the fix/patch I get:
>>>
>>> device# i2c md 0x60 0 4
>>> 0000: 62 6f 6f 74    boot
>>>
>>> Which is correct. Also the reads were working in linux leading to my original suspicion that there might be something going on in the driver. Hopefully that answers your question let me know if you have anymore.
>>
>> I had a bit of a look at this. If you look at dm_i2c_read() it actually builds the address into the buffer it sends. So when it gets to __dw_i2c_write() the alen parameter is always 0. That function is actually a holdover from before driver model, so one day the alen and addr parameters will go away.
>>
>> I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
>> command.
>>
>> In the designware_i2c_xfer(), try printing out the bytes that it gets in each message using i2c_dump_msgs().
>>
>> Also check the i2c_get_chip() function which you are using. See if
>> chip->offset_len is set to 1 as it should be, for your device. If not,
>> perhaps something is missing.
>>
>> In short I am not really sure what is going on, but I think it needs more investigation.
>>
>> BTW with this mailing list we like people to reply inline or at the bottom, not at the top.
>>
>> Regards,
>> Simon
>>
>>>
>>> Best regards,
>>>
>>> -Cooper Duffin
>>> -----Original Message-----
>>> From: Simon Glass <[hidden email]>
>>> Sent: Friday, November 6, 2020 10:51 AM
>>> To: Duffin, CooperX <[hidden email]>
>>> Cc: U-Boot Mailing List <[hidden email]>;
>>> [hidden email]; Tom Rini <[hidden email]>; Robert
>>> Beckett <[hidden email]>; Heiko Schocher <[hidden email]>;
>>> Wolgang Denk <[hidden email]>; Ian Ray <[hidden email]>
>>> Subject: Re: [dwi2c PATCH v1] dwi2c add offsets to reads
>>>
>>> Hi Cduffinx,
>>>
>>> On Thu, 5 Nov 2020 at 14:26, cduffinx <[hidden email]> wrote:
>>>>
>>>> modify the designware_i2c_xfer function to use 1 byte per address,
>>>> it was set to 0 before which makes it think its reading a register type.
>>>> Added offset of where it is supposed to read from. Before it was
>>>> always reading from offset 0 despite specifying the offset in the
>>>> higher level function.
>>>>
>>>> Signed-off-by: Cooper Duffin <[hidden email]>
>>>> Signed-off-by: cduffinx <[hidden email]>
>>>> ---
>>>>
>>>>  drivers/i2c/designware_i2c.c | 5 +++--
>>>>  drivers/i2c/i2c-uclass.c     | 1 +
>>>>  include/i2c.h                | 1 +
>>>>  3 files changed, 5 insertions(+), 2 deletions(-)
>>>>
>>>
>>> Thanks for the patch!
>>>
>>> Is there a test that was failing before (test/dm/i2c.c) or should we add a new one to catch this?
>>>
>>> Regards,
>>> Simon
>>
>> [Duffin, CooperX]
>> Thanks for the reply Simon.  I tried a couple more things.
>>
>> Simon Glass <[hidden email]> wrote:
>>> I wonder if your device does not support multiple-byte reads or writes? Can you try the i2c md with a single byte? There is a DM_I2C_CHIP_WR_ADDRESS option to handle this - see the 'i2c flags'
>>> command.
>>
>> I tried with the flag DM_I2C_CHIP_WR_ADDRESS but it did not make a difference. A single byte read will yield the following:
>>
>> Device # i2c md 0x60 0 1
>> 0000: 6f    o
>>
>> Which is not correct in fact it doesn’t seem to matter how much I read it only picks up the second character I wrote to it. For example if I read 16 characters I get:
>> device# i2c flags 0x60 4
>> device # i2c md 0x60 0 10
>> 0000: 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f 6f    oooooooooooooooo
>>
>> I can tell the writes are working because I am writing to an LED display and I can see the proper characters get displayed. Also I think my i2c device needs restarts in-between each byte for it to work properly, so I need to be able to read individual bytes with there corresponding offsets, also i2c-tools supports this.
>>
>> Simon Glass <[hidden email]> wrote:
>>> Also check the i2c_get_chip() function which you are using. See if
>>> chip->offset_len is set to 1 as it should be, for your device. If not,
>>> perhaps something is missing.
>> If I use this command I get:
>>
>> device # i2c olen 0x60
>> 1
>>
>> This is  without the patch BTW.

Hard to say here anything usefull, without the chance to try out...

trying with an i2c epprom (imx6 based board)

=> i2c md 0x58 0 10
0000: 01 00 04 23 00 02 b1 61 00 23 00 10 00 00 03 09    ...#...a.#......
=> i2c md 0x58 0 1
0000: 01    .
=> i2c md 0x58 1 1
0001: 00    .
=> i2c md 0x58 2 1
0002: 04    .
=> i2c md 0x58 3 1
0003: 23    #
=>

=> i2c flags 0x58
0
=> i2c olen 0x58
1
=>

May you can enable debug in drivers/i2c/designware_i2c.c driver?

So we should see, what sort of messages designware_i2c_xfer()
gets ... and may have an idea... and may add

717                 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);

also a dump of msg->buf and msg->len.

bye,
Heiko
--
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-52   Fax: +49-8142-66989-80   Email: [hidden email]