On Wed, Oct 24, 2012 at 6:52 PM, Felipe Balbi [off-list ref] wrote:

On Wed, Oct 24, 2012 at 09:14:29AM -0700, Dmitry Torokhov wrote:

quoted

All of _their_ resources, exactly. They do not own nor control pins so
they should not be bothered with them either. Look, when you see that

except that they *own* the pins. Now that the muxer has been setup
properly, this particular IP owns the pins.

This is true. It is then also reflected in the device model.
And in debugfs, which is very helpful when debugging. If I
cat
/sys/kernel/debug/pinctrl/pinctrl-db8500/pins

I can see a list of all pins on this ASIC and what device
is using it. It is all due to the fact that each driver use
[devm_]pinctrl_get(&dev) ad the struct device * pointer
is used with dev_name() to print the corresponding
device name.

When using hogs it just says the name of the pin
controller and the pins aren't really connected to their
real consumers :-P

Example:

Pinmux settings per pin
Format: pin (name): mux_owner gpio_owner hog?
pin 0 (GPIO0_AJ5): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 1 (GPIO1_AJ3): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 2 (GPIO2_AH4): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 3 (GPIO3_AH3): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 4 (GPIO4_AH6): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 5 (GPIO5_AG6): (MUX UNCLAIMED) DB8500:5
pin 6 (GPIO6_AF6): pinctrl-db8500 (GPIO UNCLAIMED) function ipgpio
group ipgpio0_c_1
pin 7 (GPIO7_AG5): pinctrl-db8500 (GPIO UNCLAIMED) function ipgpio
group ipgpio1_c_1
pin 8 (GPIO8_AD5): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 9 (GPIO9_AE4): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 10 (GPIO10_AF5): nmk-i2c.2 (GPIO UNCLAIMED) function i2c2 group i2c2_b_2
pin 11 (GPIO11_AG4): nmk-i2c.2 (GPIO UNCLAIMED) function i2c2 group i2c2_b_2
pin 12 (GPIO12_AC4): pinctrl-db8500 (GPIO UNCLAIMED) function msp0
group msp0txrx_a_1
pin 13 (GPIO13_AF3): pinctrl-db8500 (GPIO UNCLAIMED) function msp0
group msp0tfstck_a_1
pin 14 (GPIO14_AE3): pinctrl-db8500 (GPIO UNCLAIMED) function msp0
group msp0tfstck_a_1
pin 15 (GPIO15_AC3): pinctrl-db8500 (GPIO UNCLAIMED) function msp0
group msp0txrx_a_1
pin 16 (GPIO16_AD3): nmk-i2c.1 (GPIO UNCLAIMED) function i2c1 group i2c1_b_2
pin 17 (GPIO17_AD4): nmk-i2c.1 (GPIO UNCLAIMED) function i2c1 group i2c1_b_2

As you can see pins 6,7,12-15 are using hogs. Sure I can see
the name of the function but that is just a string albeit
helpful.

Pins 10,11,16,17 are requested directly from the i2c driver
and shows up connected to its device.

Yours,
Linus Walleij