Re: [linux-sunxi] clk_out_a usage in mainline

John, my reference design is OLIMEX EVB, CPU manual and Linux kernel 4.4 EVB has no pullup on the pin PI12, CPU manual has no mention of a possible pullup for the clk_out_a and Linux Kernel does not enable internal pullup Maybe something can be better documented ? Please, do not be

Re: [linux-sunxi] clk_out_a usage in mainline

On Fri, Dec 11, 2015 at 4:51 PM, wrote: > The most up to date documentation is the following > https://github.com/allwinner-zh > > > documents/A20/A20_User_Manual_v1.4_20150510.pdf > > Page 289 has no mention of the fact that to actually have clk_out_a you need > to set the

Re: [linux-sunxi] clk_out_a usage in mainline

"goo...@engidea.com" wrote: >> AFAIK board designs using this all have an external pull-up resistor.>> >> Maybe this pin is open-drain by design? >> Also, for higher clock rates you should increase the drive>> 30 mA should be >> good enough for clock rates up to 50 MHz. >

Re: [linux-sunxi] clk_out_a usage in mainline

On Fri, Dec 11, 2015 at 4:03 PM, wrote: >> AFAIK board designs using this all have an external pull-up resistor. >> Maybe this pin is open-drain by design? >> >> Also, for higher clock rates you should increase the drive strength. >> >> 30 mA should be good enough for clock

Re: [linux-sunxi] clk_out_a usage in mainline

> > AFAIK board designs using this all have an external pull-up resistor. > Maybe this pin is open-drain by design? > > Also, for higher clock rates you should increase the drive strength. > > 30 mA should be good enough for clock rates up to 50 MHz. > Assuming that what you write is

Re: [linux-sunxi] clk_out_a usage in mainline

The most up to date documentation is the following https://github.com/allwinner-zh documents /A20 / *A20_User_Manual_v1.4_20150510.pdf* Page 289 has no mention of the fact that to actually

Re: [linux-sunxi] clk_out_a usage in mainline

I am able to have a 32Khz signal output from PI12 if I add a pullup definition to clk_out_a_pins_a: clk_out_a@0 { allwinner,pins = "PI12"; allwinner,function = "clk_out_a"; allwinner,drive = ; /* allwinner,pull = ; */ allwinner,pull = ; in the file sun71-a20-dtsi Clearly the rising front is a

Re: [linux-sunxi] clk_out_a usage in mainline

Dear Maxime and Danny I also have an A20, the Olimex SOM + EVB and would like to output a 6MHz clock on pin PI12 I did follow the thread and I am obviously doing something wrong but so far I cannot guess what. Let me tell you what I have found working 1) Testing the GPIO pin with the shell

Re: [linux-sunxi] clk_out_a usage in mainline

Hi, On Fri, Dec 11, 2015 at 1:26 AM, wrote: > I am able to have a 32Khz signal output from PI12 if I add a pullup > definition to > > clk_out_a_pins_a: clk_out_a@0 { > allwinner,pins = "PI12"; > allwinner,function = "clk_out_a"; > allwinner,drive = ; > /* allwinner,pull = ;

Re: [linux-sunxi] clk_out_a usage in mainline

I am adding a few more details on my previous request The kernel I am using is Linux version 4.4.0-rc4-00086-g6764e5e-dirty (damiano@HP-500-507nl) (gcc version 4.9.2 (Ubuntu/Linaro 4.9.2-10ubuntu10) ) #7 SMP Thu Dec 10 08:27:17 CET 2015 pinctrl.maps report the following for the PI12 pin

Re: [linux-sunxi] clk_out_a usage in mainline

Hi, On Mon, Dec 07, 2015 at 12:49:42AM +0100, Danny Milosavljevic wrote: > Hi Chen-Yu, > > indeed, it works now. > > In case someone else wants to use it, it works like this: > > in the dts file I put: > > / { > tss463aa { > compatible = "atmel,tss463aa"; >

Re: [linux-sunxi] clk_out_a usage in mainline

Hi Chen-Yu, indeed, it works now. In case someone else wants to use it, it works like this: in the dts file I put: / { tss463aa { compatible = "atmel,tss463aa"; clocks = <_out_a>; pinctrl-0 = <_out_a_pins_a>; pinctrl-names =

Re: [linux-sunxi] clk_out_a usage in mainline

Hi, On Fri, Nov 27, 2015 at 10:42:53PM +0100, Danny Milosavljevic wrote: > Hi, > > I'm trying to use A20 clk_out_a in Linux 4.4-rc1. > > I wrote a kernel module in order to enable the clock: > http://svn.nomike.com/playground/trunk/Navi/TSS463AA/Linux/tss463aa.c > > However, it does not work,

Re: [linux-sunxi] clk_out_a usage in mainline

On Tue, Dec 1, 2015 at 11:01 PM, Danny Milosavljevic wrote: > Hi Maxime, > > On Tue, 1 Dec 2015 10:47:37 +0100 > Maxime Ripard wrote: >> Did you mux the clk_out pin somewhere? > > Not manually, no. Is that not done by the sunxi clock