linux-stable.git/drivers/gpio, branch v5.2.7

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

2019-08-06T17:08:16+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: Preserve desc->flags when setting state

2019-08-06T17:08:16+00:00

commit d95da993383c78f7efd25957ba3af23af4b1c613 upstream.

desc->flags may already have values set by of_gpiochip_add() so make
sure that this isn't undone when setting the initial direction.

Cc: stable@vger.kernel.org
Fixes: 3edfb7bd76bd1cba ("gpiolib: Show correct direction from the beginning")
Signed-off-by: Chris Packham 
Link: https://lore.kernel.org/r/20190707203558.10993-1-chris.packham@alliedtelesis.co.nz
Signed-off-by: Linus Walleij 
Signed-off-by: Greg Kroah-Hartman

gpio: davinci: silence error prints in case of EPROBE_DEFER

2019-07-28T06:27:21+00:00

commit 541e4095f388c196685685633c950cb9b97f8039 upstream.

Silence error prints in case of EPROBE_DEFER. This avoids
multiple/duplicate defer prints during boot.

Cc: 
Signed-off-by: Keerthy 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

gpiolib: of: fix a memory leak in of_gpio_flags_quirks()

2019-07-28T06:27:21+00:00

commit 89fea04c85e85f21ef4937611055abce82330d48 upstream.

Each iteration of for_each_child_of_node puts the previous node, but in
the case of a break from the middle of the loop, there is no put, thus
causing a memory leak. Hence add an of_node_put before the break.
Issue found with Coccinelle.

Cc: 
Signed-off-by: Nishka Dasgupta 
[Bartosz: tweaked the commit message]
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman

Revert "gpio/spi: Fix spi-gpio regression on active high CS"

2019-07-28T06:27:21+00:00

commit da7f134972f473053ea9d721a1d8397546476dc4 upstream.

This reverts commit fbbf145a0e0a0177e089c52275fbfa55763e7d1d.

It seems I was misguided in my fixup, which was working at the
time but did not work on the final v5.2.

The patch tried to avoid a quirk the gpiolib code not to treat
"spi-gpio" CS gpios "special" by enforcing them to be active
low, in the belief that since the "spi-gpio" driver was
parsing the device tree on its own, it did not care to inspect
the "spi-cs-high" attribute on the device nodes.

That's wrong. The SPI core was inspecting them inside the
of_spi_parse_dt() funtion and setting SPI_CS_HIGH on the
nodes, and the driver inspected this flag when driving the
line.

As of now, the core handles the GPIO and it will consistently
set the GPIO descriptor to 1 to enable CS, strictly requireing
the gpiolib to invert it. And the gpiolib should indeed
enforce active low on the CS line.

Device trees should of course put the right flag on the GPIO
handles, but it used to not matter. If we don't enforce active
low on "gpio-gpio" we may run into ABI backward compatibility
issues, so revert this.

Cc: linux-spi@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Walleij 
Link: https://lore.kernel.org/r/20190715204529.9539-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman

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

2019-07-26T07:10:44+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

gpio: Fix return value mismatch of function gpiod_get_from_of_node()

2019-07-26T07:10:37+00:00

[ Upstream commit 025bf37725f1929542361eef2245df30badf242e ]

In case the requested gpio property is not found in the device tree, some
callers of gpiod_get_from_of_node() expect a return value of NULL, others
expect -ENOENT.
In particular devm_fwnode_get_index_gpiod_from_child() expects -ENOENT.
Currently it gets a NULL, which breaks the loop that tries all
gpio_suffixes. The result is that a gpio property is not found, even
though it is there.

This patch changes gpiod_get_from_of_node() to return -ENOENT instead
of NULL when the requested gpio property is not found in the device
tree. Additionally it modifies all calling functions to properly
evaluate the return value.

Another approach would be to leave the return value of
gpiod_get_from_of_node() as is and fix the bug in
devm_fwnode_get_index_gpiod_from_child(). Other callers would still need
to be reworked. The effort would be the same as with the chosen solution.

Signed-off-by: Georg Waibel 
Reviewed-by: Krzysztof Kozlowski 
Reviewed-by: Linus Walleij 
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

gpio: omap: Fix lost edge wake-up interrupts

2019-07-26T07:10:25+00:00

[ Upstream commit a522f1d0c381c42f3ace13b8bbeeccabdd6d2e5c ]

If an edge interrupt triggers while entering idle just before we save
GPIO datain register to saved_datain, the triggered GPIO will not be
noticed on wake-up. This is because the saved_datain and GPIO datain
are the same on wake-up in omap_gpio_unidle(). Let's fix this by
ignoring any pending edge interrupts for saved_datain.

This issue affects only idle states where the GPIO module internal
wake-up path is operational. For deeper idle states where the GPIO
module gets powered off, Linux generic wakeirqs must be used for
the padconf wake-up events with pinctrl-single driver. For examples,
please see "interrupts-extended" dts usage in many drivers.

This issue can be somewhat easily reproduced by pinging an idle system
with smsc911x Ethernet interface configured IRQ_TYPE_EDGE_FALLING. At
some point the smsc911x interrupts will just stop triggering. Also if
WLCORE WLAN is used with EDGE interrupt like it's documentation specifies,
we can see lost interrupts without this patch.

Note that in the long run we may be able to cancel entering idle by
returning an error in gpio_omap_cpu_notifier() on pending interrupts.
But let's fix the bug first.

Also note that because of the recent clean-up efforts this patch does
not apply directly to older kernels. This does fix a long term issue
though, and can be backported as needed.

Cc: Aaro Koskinen 
Cc: Grygorii Strashko 
Cc: Keerthy 
Cc: Ladislav Michl 
Cc: Peter Ujfalusi 
Cc: Russell King 
Cc: Tero Kristo 
Signed-off-by: Tony Lindgren 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

gpio: omap: ensure irq is enabled before wakeup

2019-07-26T07:10:25+00:00

[ Upstream commit c859e0d479b3b4f6132fc12637c51e01492f31f6 ]

Documentation states:

  NOTE: There must be a correlation between the wake-up enable and
  interrupt-enable registers. If a GPIO pin has a wake-up configured
  on it, it must also have the corresponding interrupt enabled (on
  one of the two interrupt lines).

Ensure that this condition is always satisfied by enabling the detection
events after enabling the interrupt, and disabling the detection before
disabling the interrupt.  This ensures interrupt/wakeup events can not
happen until both the wakeup and interrupt enables correlate.

If we do any clearing, clear between the interrupt enable/disable and
trigger setting.

Signed-off-by: Russell King 
Signed-off-by: Grygorii Strashko 
Tested-by: Tony Lindgren 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

gpio: omap: fix lack of irqstatus_raw0 for OMAP4

2019-07-26T07:10:24+00:00

[ Upstream commit 64ea3e9094a1f13b96c33244a3fb3a0f45690bd2 ]

Commit 384ebe1c2849 ("gpio/omap: Add DT support to GPIO driver") added
the register definition tables to the gpio-omap driver. Subsequently to
that commit, commit 4e962e8998cc ("gpio/omap: remove cpu_is_omapxxxx()
checks from *_runtime_resume()") added definitions for irqstatus_raw*
registers to the legacy OMAP4 definitions, but missed the DT
definitions.

This causes an unintentional change of behaviour for the 1.101 errata
workaround on OMAP4 platforms. Fix this oversight.

Fixes: 4e962e8998cc ("gpio/omap: remove cpu_is_omapxxxx() checks from *_runtime_resume()")
Signed-off-by: Russell King 
Signed-off-by: Grygorii Strashko 
Tested-by: Tony Lindgren 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin