i.MX Processors中的主题 Re: I2C command in 2014.01 u-boot on sabresd

I2C command in 2014.01 u-boot on sabresd

jaiganesh — Wed, 23 Apr 2014 12:33:41 GMT

Hello all,

I am using sabresd with 2014.01 u-boot ("mx6qsabresd_config" configuration) and I got the u-boot prompt on the board. But there is no "i2c" command by default. And I tried to bring up the "i2c" command. For this, I added these lines in "include/configs/mx6sabresd.h" file (I referred LTIB BSP u-boot code which is 2009.08 version )

/* I2C configs */

#define CONFIG_CMD_I2C

#define CONFIG_SYS_I2C 1

#define CONFIG_I2C_MXC 1

#define CONFIG_SYS_I2C_PORT I2C2_BASE_ADDR

#define CONFIG_SYS_I2C_SPEED 100000

#define CONFIG_SYS_I2C_SLAVE 0x8

And with this settings, I got the u-boot prompt with i2c command but it is not working properly. Below is the attached boot log message:

U-Boot 2014.01 (Apr 23 2014 - 17:03:14)

CPU: Freescale i.MX6Q rev1.2 at 792 MHz

Reset cause: POR

Board: MX6-SabreSD

I2C: Error, wrong i2c adapter 0 max 0 possible

ready

DRAM: 1 GiB

MMC: FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2

*** Warning - bad CRC, using default environment

Error, wrong i2c adapter 0 max 0 possible

auto-detected panel HDMI

Display: HDMI (1024x768)

In: serial

Out: serial

Err: serial

Net: FEC [PRIME]

Hit any key to stop autoboot: 0

=> i2c probe

Valid chip addresses:Error, wrong i2c adapter 0 max 0 possible

Error, wrong i2c adapter 0 max 0 possible

data abort

MAYBE you should read doc/README.arm-unaligned-accesses

pc : [<4ffa0bf4>] lr : [<4ff8d220>]

sp : 4f570dd8 ip : 00000034 fp : 00000000

r10: 00000002 r9 : 4f570f30 r8 : 4f876cc8

r7 : 00000000 r6 : ffffffff r5 : 00000000 r4 : 4ffa0bd0

r3 : 00000083 r2 : 00000060 r1 : 00000000 r0 : 00000000

Flags: nZCv IRQs off FIQs off Mode SVC_32

Resetting CPU ...

resetting ...

U-Boot 2014.01 (Apr 23 2014 - 17:03:14)

CPU: Freescale i.MX6Q rev1.2 at 792 MHz

Reset cause: WDOG

Board: MX6-SabreSD

I2C: Error, wrong i2c adapter 0 max 0 possible

ready

DRAM: 1 GiB

MMC: FSL_SDHC: 0, FSL_SDHC: 1, FSL_SDHC: 2

*** Warning - bad CRC, using default environment

Error, wrong i2c adapter 0 max 0 possible

auto-detected panel HDMI

Display: HDMI (1024x768)

In: serial

Out: serial

Err: serial

Net: FEC [PRIME]

Hit any key to stop autoboot: 0

As you can see, when I try for "i2c probe", the board is reset with "Error, wrong i2c adapter 0 max 0 possible" error message. Do I need any other configuration for "i2c" command to work properly?

Thanks in advance.

Re: I2C command in 2014.01 u-boot on sabresd

fabio_estevam — Wed, 23 Apr 2014 14:39:50 GMT

Take a look at mx6qsabreauto board in U-boot 2014.04 for a working reference.

Re: I2C command in 2014.01 u-boot on sabresd

jaiganesh — Fri, 25 Apr 2014 09:41:19 GMT

Hi Fabio,

I took mx6qsabrelite in 2014.01 as reference (where i2c is working fine in sabrelite baord) and looked at it. And i guess that the error we saw in the boot log is thrown from the file "drivers/i2c/i2c_core.c", in the function "i2c_set_bus_num()", line

max = ll_entry_count(struct i2c_adapter, i2c);

if (I2C_ADAPTER(bus) >= max) {

printf("Error, wrong i2c adapter %d max %d possible\n",

I2C_ADAPTER(bus), max);

return -2;

}

I put some debug messages there and found that the variable "max" is set to 0 in case of sabresd, but in the case of sabrelite it is 3. This function is called from "arch/arm/lib/board.c" which is common to both sabrelite and sabresd and I guess no board specific confgiuration with respect to i2c is made before that function call. So I wonder how the "max" variable differs in these two cases. Meanwhile I googeled for "ll_entry_count" which specifies " returns the number of elements in the linker generated array" and I am not sure what is linker generated array.

And so I cannot guess what is the cause of this error. Can you guide me in this issue?

Thanks

Re: I2C command in 2014.01 u-boot on sabresd

fabio_estevam — Fri, 25 Apr 2014 14:44:48 GMT

You would better enter a post in the u-boot list.

Re: I2C command in 2014.01 u-boot on sabresd

niklasmolin — Tue, 06 May 2014 23:36:52 GMT

Hi Jai.

Did you manage to solve this problem?

I also have the same problem (right now using 2013.10).

When I tried to set something (speed) or do a probe, u-boot restarts.

U-Boot > i2c speed 100000

Setting bus speed to 100000 Hz

data abort

MAYBE you should read doc/README.arm-unaligned-accesses

pc : [<4ff9ad30>] lr : [<4ff9a75c>]

sp : 4f584e00 ip : 00000000 fp : 4f585860

r10: 4ffba700 r9 : 4f584f38 r8 : 00000003

r7 : 00000002 r6 : 4f5858a4 r5 : 4ffb983c r4 : 00000000

r3 : 00000039 r2 : 00000300 r1 : 4ffae44c r0 : 4ffae4dc

Flags: nzCv IRQs off FIQs off Mode SVC_32

Resetting CPU ...

resetting ...

Thanks,

Niklas

Re: I2C command in 2014.01 u-boot on sabresd

fabio_estevam — Wed, 07 May 2014 00:00:08 GMT

Niklas,

I have just tested with U-boot 2014.04 and the i2c commands work fine. You can apply this patch that adds pfuze100 pmic which is connected via i2c:

[U-Boot] [PATCH v3] mx6sabred: Add PFUZE100 PMIC support

Re: I2C command in 2014.01 u-boot on sabresd

jaiganesh — Wed, 07 May 2014 06:36:49 GMT

Thanks Fabio.It works fine in 2014.04 u-boot with the above patch.

And for the post I made above, I made a small mistake in adding a line in ""include/configs/mx6sabresd.h". I added " #define CONFIG_I2C_MXC " but it must be "#define CONFIG_SYS_I2C_MXC". After changing this line i2c command works but "i2c probe" does not show any devices connected to it even after probing all the buses.

Re: I2C command in 2014.01 u-boot on sabresd

jaiganesh — Wed, 07 May 2014 06:40:00 GMT

Hi Nilkas,

For the post I made above, I made a small mistake in adding a line in ""include/configs/mx6sabresd.h". I added " #define CONFIG_I2C_MXC " but it must be "#define CONFIG_SYS_I2C_MXC". After changing this line i2c command works but "i2c probe" does not show any devices connected to it even after probing all the buses.

But it works fine in 2014.04 u-boot with the patch posted by Fabio.[[U-Boot] [PATCH v3] mx6sabred: Add PFUZE100 PMIC support]. Please do try this.

Re: I2C command in 2014.01 u-boot on sabresd

niklasmolin — Thu, 08 May 2014 00:13:01 GMT

Thanks Fabio.

I have a working version now that handles both I2C1 and I2C3 busses.

Regards,

Niklas

Re: I2C command in 2014.01 u-boot on sabresd

fabio_estevam — Thu, 08 May 2014 00:45:26 GMT

Jai and Niklas,

Glad to know that this issue has been resolved. Could you please mark my reply as 'Correct Answer'?