Re: replacement for /sys/kernel/debug/omap_mux in DT/pinctrl land ?

[Koen Kooi <koen@dominion.thruhere.net>]

Op 26 sep. 2012, om 20:52 heeft Tony Lindgren <tony@atomide.com> het volgende geschreven:

> * Koen Kooi <koen@dominion.thruhere.net> [120926 10:23]:
>> 
>> Op 26 sep. 2012, om 18:15 heeft Matt Porter <mporter@ti.com> het volgende geschreven:
>> 
>>> On Wed, Sep 26, 2012 at 03:03:27PM +0200, Linus Walleij wrote:
>>>> On Wed, Sep 26, 2012 at 2:56 PM, Matt Porter <mporter@ti.com> wrote:
>>>>> Adding Linus W. and lkml.
>>>>> On Wed, Sep 26, 2012 at 01:46:45PM +0200, Koen Kooi wrote:
>>>>>> Hi,
>>>>>> 
>>>>>> With a patched 3.6rc7 on my beaglebone I can set the pinmux for pins using pinctrl and that seems to work. On the 3.2 vendor tree there was the omap_mux driver with an awesome debugfs interface:
>>>>>> 
>>>>>> # cat /sys/kernel/debug/omap_mux/lcd_data0
>>>>>> name: lcd_data0.ehrpwm2A (0x44e108a0/0x8a0 = 0x0003), b NA, t NA
>>>>>> mode: OMAP_PIN_OUTPUT | OMAP_MUX_MODE3
>>>>>> signals: lcd_data0 | gpmc_a0 | pr1_mii_mt0_clk | ehrpwm2A | NA | pr1_pru1_pru_r30_0 | pr1_pru1_pru_r31_0 | gpio2_6
>>>>>> 
>>>>>> Notice how it tells me that it's muxed the PWM in 2 ways: signal name (ehrpwm2A) and register content (0x0003). Compare to pinctrl:
>>>>>> 
>>>>>> root@bone-mainline:/sys/kernel/debug/pinctrl/44e10800.pinmux# grep 8a0 *
>>>>>> pinconf-pins:pin 40 (44e108a0):
>>>>>> pingroups:pin 40 (44e108a0)
>>>>>> pinmux-pins:pin 40 (44e108a0): 4a300000.pruss (GPIO UNCLAIMED) function pinmux_pruss_led_pins group pinmux_pruss_led_pins
>>>>>> pins:pin 40 (44e108a0)  pinctrl-single
>>>>>> 
>>>>>> What is that pin muxed to? It is part of the 'pinmux_pruss_led_pins' in the DT, but debugfs remains mute on how pin 40 is muxed.
>>>>> 
>>>>> It does seem like a pretty big gap in the pinctrl/pinmux debugfs
>>>>> interface when viewed from an OMAP perspective. Ideally there would
>>>>> be a pinctrl/pinmux hook to the pinmux driver to provide the detailed
>>>>> h/w specific pin state info.
>>>> 
>>>> So add the hooks you need?
>>> 
>>> Ok. :)
>>> 
>>>> I assume you are using Tony's pinctrl-single driver, so Tony is the one to ask.
>>> 
>>> Yes, so roughly for pinctrl-single I have the following...likely broken
>>> for arbitrary register sizes but a starting point. Tony, any thoughts
>>> about this?
>>> 
>>> Koen: you just need a userspace tool that groks the raw data for human
>>> consumption. The nice thing is that the old omap_mux implementation had
>>> plenty of OMAP-isms in the parser that didn't apply to AM33xx. A
>>> userspace tool can do a better job of parsing on a per-part basis.
>>> 
>>> --- a/drivers/pinctrl/pinctrl-single.c
>>> +++ b/drivers/pinctrl/pinctrl-single.c
>>> @@ -246,7 +246,15 @@ static void pcs_pin_dbg_show(struct pinctrl_dev *pctldev,
>>> 					struct seq_file *s,
>>> 					unsigned offset)
>>> {
>>> -	seq_printf(s, " " DRIVER_NAME);
>>> +	struct pcs_device *pcs;
>>> +	unsigned val;
>>> +
>>> +	pcs = pinctrl_dev_get_drvdata(pctldev);
>>> +
>>> +	val = pcs->read(pcs->base + offset);
>>> +	val &= pcs->fmask;
>>> +
>>> +	seq_printf(s, "%08x %s " , val, DRIVER_NAME);
>>> }
>>> 
>>> static void pcs_dt_free_map(struct pinctrl_dev *pctldev,
>> 
>> Much better already:
>> 
>> root@bone-mainline:/sys/kernel/debug/pinctrl/44e10800.pinmux# grep 8a0 pins
>> pin 40 (44e108a0) 00000027 pinctrl-single 
> 
> Cool :) For the proper patch feel free to add:
> 
> Acked-by: Tony Lindgren <tony@atomide.com>
> 
>> Now I can write a userspace tool do list the current muxes without resorting to devmem2!
> 
> Yeah maybe add support to omapconf for that? I can generate
> the data for balls etc from old omap mux if you let me know the
> format you need.


It's for am335x :)