topic Re: IMX6UL Board in i.MX Processors

IMX6UL Board

mayurshankariya — Thu, 16 Nov 2017 06:31:41 GMT

Hello team,

i am using IMX6UL board. in this i am getting problem with PWM.

so could you help how to use PWM pin to control LEDs intensity?

and How to configure settings to use PWM pin?

Re: IMX6UL Board

Carlos_Musich — Thu, 16 Nov 2017 17:39:12 GMT

Hi Mayur,

In the following link you will find how to use the PWM driver with UDOO board

https://www.udoo.org/docs/Hardware_&_Accessories/PWM.html

The way in which you use the driver is the same, you just need to consider a couple of things:

You must enable the PWM node in .dtsi and you must enable the pins in the iomux node. If the pins that you are using for PWM are being configured for any other function in the device tree you must delete or comment out that configuration.

Please take a look also to the following thread PWM with iMX6UL

Regards,
Carlos

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Re: IMX6UL Board

mayurshankariya — Fri, 17 Nov 2017 11:22:02 GMT

Thank you for your helpful reply, and how can i change mode of PWM_OUT pins using IOMUX controller ? beacuse that PWM3_OUT pin is working for 1) GPIO1_IO04 (mode ALT1) 2) LCD_DATA02 (mode ALT1) 3)NAND_ALE (mode ALT3) these all mode so how to set ALT3 mode?

Re: IMX6UL Board

Carlos_Musich — Fri, 17 Nov 2017 22:47:19 GMT

Hi,

this is donde in the device tree (.dts). Please take a look to this thread.

https://community.nxp.com/thread/450118

It is not about PWM_OUT but the explanation is the same.

Re: IMX6UL Board

fabio_estevam — Sat, 18 Nov 2017 17:42:01 GMT

You can check the example from:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/imx6qdl-cubox-i.dtsi?h=v4.14

(Search for pwmleds)

Re: IMX6UL Board

mayurshankariya — Mon, 20 Nov 2017 07:04:43 GMT

thanks for your reply.

i am fresher and new for this board.

i have done same steps which you said above like 32khz settings. but when i change in .dtsi file and try to compile this file at booting image but i am not getting new image of it.

and one more thing in .dtsi file i am not getting this type of node

pinctrl_uart2: uart2grp {
                    fsl,pins = <
                            MX6QDL_PAD_EIM_D26__UART2_TX_DATA       0x1b0b1
                            MX6QDL_PAD_EIM_D27__UART2_RX_DATA       0x1b0b1
                    >;
            };

so can you tell me please what is use of these node? and i have to write this node in .dtsi file for PWM3_OUT and what is 0x1b0b1 address?

Re: IMX6UL Board

linda_zhang — Wed, 20 Mar 2019 09:04:00 GMT

The imx6ul has 8 PWM. Some might be multiplexed with others on your board. You need to decide according to your requirements.

For example, when we use PWM on MYIR's MYS-6ULX board, we need to modify dts file /MYiR-iMX-Linux-MYS/arch/arm/boot/dts/mys-imx6ull-14x14-evk.dts