linux-stable.git/drivers/gpio, branch v4.9.210

gpiolib: fix up emulated open drain outputs

2020-01-12T10:24:14+00:00

commit 256efaea1fdc4e38970489197409a26125ee0aaa upstream.

gpiolib has a corner case with open drain outputs that are emulated.
When such outputs are outputting a logic 1, emulation will set the
hardware to input mode, which will cause gpiod_get_direction() to
report that it is in input mode. This is different from the behaviour
with a true open-drain output.

Unify the semantics here.

Cc: 
Suggested-by: Linus Walleij 
Signed-off-by: Russell King 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpio: mpc8xxx: Don't overwrite default irq_set_type callback

2020-01-04T12:41:01+00:00

[ Upstream commit 4e50573f39229d5e9c985fa3b4923a8b29619ade ]

The per-SoC devtype structures can contain their own callbacks that
overwrite mpc8xxx_gpio_devtype_default.

The clear intention is that mpc8xxx_irq_set_type is used in case the SoC
does not specify a more specific callback. But what happens is that if
the SoC doesn't specify one, its .irq_set_type is de-facto NULL, and
this overwrites mpc8xxx_irq_set_type to a no-op. This means that the
following SoCs are affected:

- fsl,mpc8572-gpio
- fsl,ls1028a-gpio
- fsl,ls1088a-gpio

On these boards, the irq_set_type does exactly nothing, and the GPIO
controller keeps its GPICR register in the hardware-default state. On
the LS1028A, that is ACTIVE_BOTH, which means 2 interrupts are raised
even if the IRQ client requests LEVEL_HIGH. Another implication is that
the IRQs are not checked (e.g. level-triggered interrupts are not
rejected, although they are not supported).

Fixes: 82e39b0d8566 ("gpio: mpc8xxx: handle differences between incarnations at a single place")
Signed-off-by: Vladimir Oltean 
Link: https://lore.kernel.org/r/20191115125551.31061-1-olteanv@gmail.com
Tested-by: Michael Walle 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

gpio: max77620: Fixup debounce delays

2019-11-28T17:28:05+00:00

commit b0391479ae04dfcbd208b9571c375064caad9a57 upstream.

When converting milliseconds to microseconds in commit fffa6af94894
("gpio: max77620: Use correct unit for debounce times") some ~1 ms gaps
were introduced between the various ranges supported by the controller.
Fix this by changing the start of each range to the value immediately
following the end of the previous range. This way a debounce time of,
say 8250 us will translate into 16 ms instead of returning an -EINVAL
error.

Typically the debounce delay is only ever set through device tree and
specified in milliseconds, so we can never really hit this issue because
debounce times are always a multiple of 1000 us.

The only notable exception for this is drivers/mmc/host/mmc-spi.c where
the CD GPIO is requested, which passes a 1 us debounce time. According
to a comment preceeding that code this should actually be 1 ms (i.e.
1000 us).

Reported-by: Pavel Machek 
Signed-off-by: Thierry Reding 
Acked-by: Pavel Machek 
Cc: 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpio: syscon: Fix possible NULL ptr usage

2019-11-25T08:53:48+00:00

[ Upstream commit 70728c29465bc4bfa7a8c14304771eab77e923c7 ]

The priv->data->set can be NULL while flags contains GPIO_SYSCON_FEAT_OUT
and chip->set is valid pointer. This happens in case the controller uses
the default GPIO setter. Always use chip->set to access the setter to avoid
possible NULL pointer dereferencing.

Signed-off-by: Marek Vasut 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

gpio: max77620: Use correct unit for debounce times

2019-11-06T11:18:07+00:00

[ Upstream commit fffa6af94894126994a7600c6f6f09b892e89fa9 ]

The gpiod_set_debounce() function takes the debounce time in
microseconds. Adjust the switch/case values in the MAX77620 GPIO to use
the correct unit.

Signed-off-by: Thierry Reding 
Link: https://lore.kernel.org/r/20191002122825.3948322-1-thierry.reding@gmail.com
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

gpio: fix line flag validation in lineevent_create

2019-09-21T05:14:04+00:00

commit 5ca2f54b597c816df54ff1b28eb99cf7262b955d upstream.

lineevent_create should not allow any of GPIOHANDLE_REQUEST_OUTPUT,
GPIOHANDLE_REQUEST_OPEN_DRAIN or GPIOHANDLE_REQUEST_OPEN_SOURCE to be set.

Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines")
Cc: stable 
Signed-off-by: Kent Gibson 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpio: fix line flag validation in linehandle_create

2019-09-21T05:14:04+00:00

commit e95fbc130a162ba9ad956311b95aa0da269eea48 upstream.

linehandle_create should not allow both GPIOHANDLE_REQUEST_INPUT
and GPIOHANDLE_REQUEST_OUTPUT to be set.

Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines")
Cc: stable 
Signed-off-by: Kent Gibson 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpiolib: never report open-drain/source lines as 'input' to user-space

2019-09-06T08:19:37+00:00

commit 2c60e6b5c9241b24b8b523fefd3e44fb85622cda upstream.

If the driver doesn't support open-drain/source config options, we
emulate this behavior when setting the direction by calling
gpiod_direction_input() if the default value is 0 (open-source) or
1 (open-drain), thus not actively driving the line in those cases.

This however clears the FLAG_IS_OUT bit for the GPIO line descriptor
and makes the LINEINFO ioctl() incorrectly report this line's mode as
'input' to user-space.

This commit modifies the ioctl() to always set the GPIOLINE_FLAG_IS_OUT
bit in the lineinfo structure's flags field. Since it's impossible to
use the input mode and open-drain/source options at the same time, we
can be sure the reported information will be correct.

Fixes: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information")
Cc: stable 
Signed-off-by: Bartosz Golaszewski 
Link: https://lore.kernel.org/r/20190806114151.17652-1-brgl@bgdev.pl
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

gpiolib: fix incorrect IRQ requesting of an active-low lineevent

2019-08-06T16:29:40+00:00

commit 223ecaf140b1dd1c1d2a1a1d96281efc5c906984 upstream.

When a pin is active-low, logical trigger edge should be inverted to match
the same interrupt opportunity.

For example, a button pushed triggers falling edge in ACTIVE_HIGH case; in
ACTIVE_LOW case, the button pushed triggers rising edge. For user space the
IRQ requesting doesn't need to do any modification except to configuring
GPIOHANDLE_REQUEST_ACTIVE_LOW.

For example, we want to catch the event when the button is pushed. The
button on the original board drives level to be low when it is pushed, and
drives level to be high when it is released.

In user space we can do:

	req.handleflags = GPIOHANDLE_REQUEST_INPUT;
	req.eventflags = GPIOEVENT_REQUEST_FALLING_EDGE;

	while (1) {
		read(fd, &dat, sizeof(dat));
		if (dat.id == GPIOEVENT_EVENT_FALLING_EDGE)
			printf("button pushed\n");
	}

Run the same logic on another board which the polarity of the button is
inverted; it drives level to be high when pushed, and level to be low when
released. For this inversion we add flag GPIOHANDLE_REQUEST_ACTIVE_LOW:

	req.handleflags = GPIOHANDLE_REQUEST_INPUT |
		GPIOHANDLE_REQUEST_ACTIVE_LOW;
	req.eventflags = GPIOEVENT_REQUEST_FALLING_EDGE;

At the result, there are no any events caught when the button is pushed.
By the way, button releasing will emit a "falling" event. The timing of
"falling" catching is not expected.

Cc: stable@vger.kernel.org
Signed-off-by: Michael Wu 
Tested-by: Bartosz Golaszewski 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpiolib: Fix references to gpiod_[gs]et_*value_cansleep() variants

2019-08-04T07:33:24+00:00

[ Upstream commit 3285170f28a850638794cdfe712eb6d93e51e706 ]

Commit 372e722ea4dd4ca1 ("gpiolib: use descriptors internally") renamed
the functions to use a "gpiod" prefix, and commit 79a9becda8940deb
("gpiolib: export descriptor-based GPIO interface") introduced the "raw"
variants, but both changes forgot to update the comments.

Readd a similar reference to gpiod_set_value(), which was accidentally
removed by commit 1e77fc82110ac36f ("gpio: Add missing open drain/source
handling to gpiod_set_value_cansleep()").

Signed-off-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/20190701142738.25219-1-geert+renesas@glider.be
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin