[STLinux Kernel] [PATCH 6/6] pinctrl: st: Display pin's function when printing pinctrl debug information

[Lee Jones]

On Wed, 18 Mar 2015, Maxime Coquelin wrote:

> Hi Lee,
> 
> On 03/18/2015 11:51 AM, Lee Jones wrote:
> >Great for easily determining which mode a pin is operating in.
> >This patch was particularly helpful when debugging a recent GPIO/
> >Pinctrl disparity issue.
> >
> >Before:
> >     $ cat /sys/kernel/debug/pinctrl/<pin-controller>/pinconf-pins
> >       pin 33 (PIO4[1]):[OE:0,PU:0,OD:0]
> >              [retime:0,invclk:0,clknotdat:0,de:0,rt-clk:0,rt-delay:0]
> >
> >After [GPIO]:
> >     $ cat /sys/kernel/debug/pinctrl/<pin-controller>/pinconf-pins
> >       pin 33 (PIO4[1]):[OE:0,PU:0,OD:0] GPIO
> >              [retime:0,invclk:0,clknotdat:0,de:0,rt-clk:0,rt-delay:0]
> >
> >After [Alt]:
> >     $ cat /sys/kernel/debug/pinctrl/<pin-controller>/pinconf-pins
> >       pin 33 (PIO4[1]):[OE:0,PU:0,OD:0] Alt Fn 2
> >              [retime:0,invclk:0,clknotdat:0,de:0,rt-clk:0,rt-delay:0]
> >
> >Signed-off-by: Lee Jones <lee.jones at linaro.org>
> >---
> >  drivers/pinctrl/pinctrl-st.c | 12 +++++++++++-
> >  1 file changed, 11 insertions(+), 1 deletion(-)
> A couple of comments below.
> Once fixed, you can add my:
> Acked-by: Maxime Coquelin <maxime.coquelin at st.com>
> 
> 
> 
> >
> >diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c
> >index 1cda40e..d5b2ffa 100644
> >--- a/drivers/pinctrl/pinctrl-st.c
> >+++ b/drivers/pinctrl/pinctrl-st.c
> >@@ -1058,18 +1058,28 @@ static void st_pinconf_dbg_show(struct pinctrl_dev *pctldev,
> >  {
> >  	struct st_pio_control *pc;
> >  	unsigned long config;
> >+	unsigned int function;
> >  	int offset = st_gpio_pin(pin_id);
> >+	char f[64];
> 64 bytes is way too big here

Ah yes, this is legacy from when the message was much larger.

Initially, it was "WARN: Pin in GPIO mode -- this status is invalid"

But this incarnation is much nicer I thought.

Good spot.  Will fix.

> >  	mutex_unlock(&pctldev->mutex);
> >  	pc = st_get_pio_control(pctldev, pin_id);
> >  	st_pinconf_get(pctldev, pin_id, &config);
> >  	mutex_lock(&pctldev->mutex);
> >-	seq_printf(s, "[OE:%ld,PU:%ld,OD:%ld]\n"
> >+
> >+	function = st_pctl_get_pin_function(pc, offset);
> >+	if (function)
> >+		sprintf(f, "Alt Fn %d", function);
> Please use snprintf.

Of course.  Will fix.

> >+	else
> >+		sprintf(f, "GPIO");
> >+
> >+	seq_printf(s, "[OE:%d,PU:%ld,OD:%ld]\t%s\n"
> >  		"\t\t[retime:%ld,invclk:%ld,clknotdat:%ld,"
> >  		"de:%ld,rt-clk:%ld,rt-delay:%ld]",
> >  		!st_gpio_get_direction(&pc_to_bank(pc)->gpio_chip, offset),
> >  		ST_PINCONF_UNPACK_PU(config),
> >  		ST_PINCONF_UNPACK_OD(config),
> >+		f,
> >  		ST_PINCONF_UNPACK_RT(config),
> >  		ST_PINCONF_UNPACK_RT_INVERTCLK(config),
> >  		ST_PINCONF_UNPACK_RT_CLKNOTDATA(config),
> 
> Thanks,
> Maxime

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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