linux.git/drivers/pinctrl/intel/pinctrl-intel.c, branch v5.10

pinctrl: intel: Actually disable Tx and Rx buffers on GPIO request

2020-12-09T08:08:18+00:00

Mistakenly the buffers (input and output) become enabled together for a short
period of time during GPIO request. This is problematic, because instead of
initial motive to disable them in the commit af7e3eeb84e2
("pinctrl: intel: Disable input and output buffer when switching to GPIO"),
the driven value on the pin, which might be used as an IRQ line, brings
firmwares of some touch pads to an awkward state that needs a full power off
to recover. Fix this, as stated in the culprit commit, by disabling the buffers.

Fixes: af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer when switching to GPIO")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=210497
Reported-by: Pierre-Louis Bossart 
Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg 
Tested-by: Pierre-Louis Bossart 
Tested-by: Kai-Heng Feng 
Link: https://lore.kernel.org/r/20201208182403.40435-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij

pinctrl: intel: Set default bias in case no particular value given

2020-10-26T11:26:50+00:00

When GPIO library asks pin control to set the bias, it doesn't pass
any value of it and argument is considered boolean (and this is true
for ACPI GpioIo() / GpioInt() resources, by the way). Thus, individual
drivers must behave well, when they got the resistance value of 1 Ohm,
i.e. transforming it to sane default.

In case of Intel pin control hardware the 5 kOhm sounds plausible
because on one hand it's a minimum of resistors present in all
hardware generations and at the same time it's high enough to minimize
leakage current (will be only 200 uA with the above choice).

Fixes: e57725eabf87 ("pinctrl: intel: Add support for hardware debouncer")
Reported-by: Jamie McClymont 
Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Fix 2 kOhm bias which is 833 Ohm

2020-10-26T11:26:49+00:00

2 kOhm bias was never an option in Intel GPIO hardware, the available
matrix is:

	000	none
	001	1 kOhm (if available)
	010	5 kOhm
	100	20 kOhm

As easy to get the 3 resistors are gated separately and according to
parallel circuits calculations we may get combinations of the above where
the result is always strictly less than minimal resistance. Hence,
additional values can be:

	011	~833.3 Ohm
	101	~952.4 Ohm
	110	~4 kOhm
	111	~800 Ohm

That said, convert TERM definitions to be the bit masks to reflect the above.

While at it, enable the same setting for pull down case.

Fixes: 7981c0015af2 ("pinctrl: intel: Add Intel Sunrisepoint pin controller and GPIO support")
Cc: Jamie McClymont 
Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Extract intel_pinctrl_get_soc_data() helper for wider use

2020-08-18T13:46:39+00:00

intel_pinctrl_get_soc_data() helper can be used in few driver instead of
open-coded variants. Thus, extract it as a standalone API.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Make use of for_each_requested_gpio_in_range()

2020-06-22T08:01:59+00:00

Make use of for_each_requested_gpio_in_range() instead of home grown analogue.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Protect IO in few call backs by lock

2020-06-22T07:58:52+00:00

Protect IO in intel_gpio_get_direction(), intel_gpio_community_irq_handler(),
intel_config_get_debounce() and intel_config_get_pull() by lock. Even for
simple readl() we better serialize IO to avoid potential problems.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Split intel_config_get() to three functions

2020-06-22T07:58:51+00:00

Split intel_config_get() to three functions, i.e. intel_config_get() and
two helpers intel_config_get_pull() and intel_config_get_debounce() to be
symmetrical with intel_config_set*().

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Drop the only label in the code for consistency

2020-06-22T07:58:51+00:00

Drop the only label in the code, i.e. in intel_config_set_debounce(),
for consistency with the rest. In entire driver we use multipoint
return.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Get rid of redundant 'else' in intel_config_set_debounce()

2020-06-22T07:58:51+00:00

In a code like
	if (...) {
		...
		goto label;
	} else {
		...
	}
the 'else' keyword is redundant. Get rid of it for better readability.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg

pinctrl: intel: Make use of IRQ_RETVAL()

2020-06-22T07:58:51+00:00

Instead of using bitwise operations against returned values,
which is a bit fragile, convert IRQ handler to count amount of
GPIO groups, where at least one interrupt happened, and convert
it to returned value by IRQ_RETVAL() macro.

Signed-off-by: Andy Shevchenko 
Acked-by: Mika Westerberg