Am437x Gp evm /dev missing spi ?

Ash P

Other Parts Discussed in Thread: ASH

Hi Forum,

I recently purchased a am437x gp evm. It has 5xSPI ports. But when i go to /dev i am unable to see any spi devices. I tried using mknod to create spi1 but i am unable to open the device. Please guide me through the right direction.

Regards

-Ash

over 9 years ago

0 Biser Gatchev-XID over 9 years ago

TI__Guru**** 393215 points

Hi,

It's true that the AM437X processor has 5 McSPI interfaces, but the processor pins are multifunctional and from what I see on the GP EVM schematic most of the McSPI pins are occupied by other functions. Only SPI1 is available on GPIO header J30. You can find EVM documentation here: processors.wiki.ti.com/.../AM437X_EVM_Boards As for software configuration, check this wiki: processors.wiki.ti.com/.../Linux_Core_SPI_User's_Guide

0 Ash P over 9 years ago in reply to Biser Gatchev-XID

Expert 1570 points

Hi Biser,

After populating the dts file as mentioned in the wiki page should i rebuild the kernel sources? should i make any changes in the menu config???

Regards
-parker

0 Biser Gatchev-XID over 9 years ago in reply to Ash P

TI__Guru**** 393215 points

Changes in menuconfig are required as given in the wiki, check under "Kernel config". Yes, you should rebuild after making all changes.

0 Ash P over 9 years ago in reply to Biser Gatchev-XID

Expert 1570 points

Hi Biser,

When i try to build dtb file with the changes suggested i get a compiler error :ERROR (phandle_references): Reference to non-existent node or label "spi0_pins_s0
can you please explain where i am currently making a mistake.

regards
-Ash

0 Kemal R. Shakir over 9 years ago in reply to Ash P

TI__Guru 55345 points

Hello Ash,

It seems you have a missing pin control rule in the dts.

&am43xx_pinmux {

		spi0_pins: pinmux_spi0_pins {
			pinctrl-single,pins = <
				0x150 (PIN_INPUT | MUX_MODE0)           /* spi0_clk.spi0_clk */
				0x154 (PIN_OUTPUT | MUX_MODE0)           /* spi0_d0.spi0_d0 */
				0x158 (PIN_INPUT | MUX_MODE0)           /* spi0_d1.spi0_d1 */
				0x15c (PIN_OUTPUT | MUX_MODE0)          /* spi0_cs0.spi0_cs0 */
			>;
		};
};

Best regards,
Kemal

0 Ash P over 9 years ago in reply to Kemal R. Shakir

Expert 1570 points

Hi Kemal,

Thanks for the help. I successfully got spidev1.0 in my devices. With regards to the pins mentioned in the above command where would i be ale to view the hex pins ???

Regards
-Ash

0 Kemal R. Shakir over 9 years ago in reply to Ash P

TI__Guru 55345 points

The TI PinMux Tool processors.wiki.ti.com/.../TI_PinMux_Tool will provide you information about pin mux register values and hex configuration.

0 Ash P over 9 years ago in reply to Kemal R. Shakir

Expert 1570 points

Thanks very much for the answer.I really appreciate your help..

Regards

-Ash

Processors

Processors forum

Am437x Gp evm /dev missing spi ?