Commit Graph

40 Commits

Author SHA1 Message Date
Jiapeng Chong 38bcb51f81 leds-pca955x: Remove the unused function pca95xx_num_led_regs()
The function pca95xx_num_led_regs() is defined in the leds-pca955x.c
file, but not called elsewhere, so delete this unused function.

drivers/leds/leds-pca955x.c:149:19: warning: unused function 'pca95xx_num_led_regs'.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2411
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2022-10-21 15:08:07 +02:00
Andrew Jeffery e26557a0aa leds: pca955x: Allow zero LEDs to be specified
It's valid to use the PCA955x devices just for GPIOs and not for LEDs.
In this case, as PCA955X_TYPE_GPIO is now equivalent to
PCA955X_TYPE_NONE, remove the test for whether we have any child nodes
specified in the devicetree.

A consequence of this is it's now possible to bind the driver to a
PCA955x device when dynamically instantiated through the I2C subsystem's
`new_device` interface.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2022-03-02 09:51:40 +01:00
Andrew Jeffery ca386253ff leds: pca955x: Make the gpiochip always expose all pins
The devicetree binding allows specifying which pins are GPIO vs LED.
Limiting the instantiated gpiochip to just these pins as the driver
currently does requires an arbitrary mapping between pins and GPIOs, but
such a mapping is not implemented by the driver. As a result,
specifying GPIOs in such a way that they don't map 1-to-1 to pin indexes
does not function as expected.

Establishing such a mapping is more complex than not and even if we did,
doing so leads to a slightly hairy userspace experience as the behaviour
of the PCA955x gpiochip would depend on how the pins are assigned in the
devicetree. Instead, always expose all pins via the gpiochip to provide
a stable interface and track which pins are in use.

Specifying a pin as `type = <PCA955X_TYPE_GPIO>;` in the devicetree
becomes a no-op.

I've assessed the impact of this change by looking through all of the
affected devicetrees as of the tag leds-5.15-rc1:

```
$ git grep -l 'pca955[0123]' $(find . -name dts -type d)
arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts
arch/arm/boot/dts/aspeed-bmc-opp-mihawk.dts
arch/arm/boot/dts/aspeed-bmc-opp-mowgli.dts
arch/arm/boot/dts/aspeed-bmc-opp-swift.dts
arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts
arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
```

These are all IBM-associated platforms. I've analysed both the
devicetrees and schematics where necessary to determine whether any
systems hit the hazard of the current broken behaviour. For the most
part, the systems specify the pins as either all LEDs or all GPIOs, or
at least do so in a way such that the broken behaviour isn't exposed.

The main counter-point to this observation is the Everest system whose
devicetree describes a large number of PCA955x devices and in some cases
has pin assignments that hit the hazard. However, there does not seem to
be any use of the affected GPIOs in the userspace associated with
Everest.

Regardless, any use of the hazardous GPIOs in Everest is already broken,
so let's fix the interface and then fix any already broken userspace
with it.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2022-03-02 09:50:58 +01:00
Eddie James 239f32b4f1 leds: pca955x: Switch to i2c probe_new
The deprecated i2c probe functionality doesn't work with OF
compatible strings, as it only checks for the i2c device id. Switch
to the new way of probing and grab the match data to select the
chip type.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-20 11:00:08 +02:00
Eddie James 7c48159292 leds: pca955x: Let the core process the fwnode
Much of the fwnode processing in the PCA955x driver is now in the
LEDs core driver, so pass the fwnode in the init data when
registering the LED device. In order to preserve the existing naming
scheme, check for an empty name and set it to the LED number.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-20 11:00:08 +02:00
Eddie James e46cb6d0c7 leds: pca955x: Implement the default-state property
In order to retain the LED state after a system reboot, check the
documented default-state device tree property during initialization.
Modify the behavior of the probe according to the property.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-20 11:00:07 +02:00
Eddie James 7086625fde leds: pca955x: Add brightness_get function
Add a function to fetch the state of the hardware LED.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-20 11:00:07 +02:00
Eddie James 2420ae02ce leds: pca955x: Clean up code formatting
Format the code. Add some variables to help shorten lines.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-20 11:00:06 +02:00
Eddie James 46de3adb52 leds: pca955x: Add an IBM software implementation of the PCA9552 chip
IBM created an implementation of the PCA9552 on a PIC16F
microcontroller. The I2C device addresses are different from the
hardware PCA9552, so add a new compatible string and associated
platform data to be able to probe this device.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-08-17 22:24:21 +02:00
Linus Walleij 0987c7df8a leds: pca955x: Include the right GPIO header
This driver provides a GPIO chip, so include <linux/gpio/driver.h>
and not the legacy <linux/gpio.h> header.

Cc: Andrew Jeffery <andrew@aj.id.au>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Matt Spinler <mspinler@linux.vnet.ibm.com>
Cc: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-07-12 09:53:24 +02:00
Linus Torvalds 8a3367cc80 LED updates for 5.3-rc1
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 25okAP9I0Rmscpqjb/+GEeXH4EmL3moGzc9o/BzHRqfeO4wqYAEA+8f7L20xHe8g
 tvEGfP7mN/oBmcAfqgH5K9F4eJsBRAw=
 =NkCn
 -----END PGP SIGNATURE-----

Merge tag 'leds-for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED updates from Jacek Anaszewski:

 - Add a new LED common module for ti-lmu driver family

 - Modify MFD ti-lmu bindings
        - add ti,brightness-resolution
        - add the ramp up/down property

 - Add regulator support for LM36274 driver to lm363x-regulator.c

 - New LED class drivers with DT bindings:
        - leds-spi-byte
        - leds-lm36274
        - leds-lm3697 (move the support from MFD to LED subsystem)

 - Simplify getting the I2C adapter of a client:
        - leds-tca6507
        - leds-pca955x

 - Convert LED documentation to ReST

* tag 'leds-for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  dt: leds-lm36274.txt: fix a broken reference to ti-lmu.txt
  docs: leds: convert to ReST
  leds: leds-tca6507: simplify getting the adapter of a client
  leds: leds-pca955x: simplify getting the adapter of a client
  leds: lm36274: Introduce the TI LM36274 LED driver
  dt-bindings: leds: Add LED bindings for the LM36274
  regulator: lm363x: Add support for LM36274
  mfd: ti-lmu: Add LM36274 support to the ti-lmu
  dt-bindings: mfd: Add lm36274 bindings to ti-lmu
  leds: max77650: Remove set but not used variable 'parent'
  leds: avoid flush_work in atomic context
  leds: lm3697: Introduce the lm3697 driver
  mfd: ti-lmu: Remove support for LM3697
  dt-bindings: ti-lmu: Modify dt bindings for the LM3697
  leds: TI LMU: Add common code for TI LMU devices
  leds: spi-byte: add single byte SPI LED driver
  dt-bindings: leds: Add binding for spi-byte LED.
  dt-bindings: mfd: LMU: Add ti,brightness-resolution
  dt-bindings: mfd: LMU: Add the ramp up/down property
2019-07-09 08:59:39 -07:00
Wolfram Sang 1c57d9bd29 leds: leds-pca955x: simplify getting the adapter of a client
We have a dedicated pointer for that, so use it. Much easier to read and
less computation involved.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-06-09 13:11:04 +02:00
Thomas Gleixner 36edc93958 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 330
Based on 1 normalized pattern(s):

  this file is subject to the terms and conditions of version 2 of the
  gnu general public license see the file copying in the main
  directory of this archive for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 55 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.108941081@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00
Andy Shevchenko 967f69de81 leds: pca955x: Make use of device property API
Make use of device property API in this driver so that both OF based
system and ACPI based system can use this driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-03-31 20:12:30 +02:00
Andy Shevchenko 5b6cd445db leds: pca955x: Revert "Add ACPI support"
There is no evidence of officially registered ACPI IDs for these devices.
Thus, revert commit 44b3e31d54.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-03-31 20:12:29 +02:00
Kees Cook a86854d0c5 treewide: devm_kzalloc() -> devm_kcalloc()
The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

        devm_kzalloc(handle, a * b, gfp)

with:
        devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

        devm_kzalloc(handle, a * b * c, gfp)

with:

        devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
  devm_kzalloc(HANDLE,
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  devm_kzalloc(HANDLE,
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  devm_kzalloc(HANDLE,
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  devm_kzalloc(HANDLE,
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  devm_kzalloc(HANDLE,
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
  devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
  devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
  devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * E2
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- devm_kzalloc
+ devm_kcalloc
  (HANDLE,
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Andrew Jeffery 52ca7d0f7b leds: pca955x: Don't invert requested value in pca955x_gpio_set_value()
The PCA9552 lines can be used either for driving LEDs or as GPIOs. The
manual states that for LEDs, the operation is open-drain:

         The LSn LED select registers determine the source of the LED data.

           00 = output is set LOW (LED on)
           01 = output is set high-impedance (LED off; default)
           10 = output blinks at PWM0 rate
           11 = output blinks at PWM1 rate

For GPIOs it suggests a pull-up so that the open-case drives the line
high:

         For use as output, connect external pull-up resistor to the pin
         and size it according to the DC recommended operating
         characteristics.  LED output pin is HIGH when the output is
         programmed as high-impedance, and LOW when the output is
         programmed LOW through the ‘LED selector’ register.  The output
         can be pulse-width controlled when PWM0 or PWM1 are used.

Now, I have a hardware design that uses the LED controller to control
LEDs. However, for $reasons, we're using the leds-gpio driver to drive
the them. The reasons are here are a tangent but lead to the discovery
of the inversion, which manifested as the LEDs being set to full
brightness at boot when we expected them to be off.

As we're driving the LEDs through leds-gpio, this means wending our way
through the gpiochip abstractions. So with that in mind we need to
describe an active-low GPIO configuration to drive the LEDs as though
they were GPIOs.

The set() gpiochip callback in leds-pca955x does the following:

         ...
         if (val)
                pca955x_led_set(&led->led_cdev, LED_FULL);
         else
                pca955x_led_set(&led->led_cdev, LED_OFF);
         ...

Where LED_FULL = 255. pca955x_led_set() in turn does:

         ...
         switch (value) {
         case LED_FULL:
                ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
                break;
         ...

Where PCA955X_LS_LED_ON is defined as:

         #define PCA955X_LS_LED_ON	0x0	/* Output LOW */

So here we have some type confusion: We've crossed domains from GPIO
behaviour to LED behaviour without accounting for possible inversions
in the process.

Stepping back to leds-gpio for a moment, during probe() we call
create_gpio_led(), which eventually executes:

         if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
                state = gpiod_get_value_cansleep(led_dat->gpiod);
                if (state < 0)
                        return state;
         } else {
                state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
         }
         ...
         ret = gpiod_direction_output(led_dat->gpiod, state);

In the devicetree the GPIO is annotated as active-low, and
gpiod_get_value_cansleep() handles this for us:

         int gpiod_get_value_cansleep(const struct gpio_desc *desc)
         {
                 int value;

                 might_sleep_if(extra_checks);
                 VALIDATE_DESC(desc);
                 value = _gpiod_get_raw_value(desc);
                 if (value < 0)
                         return value;

                 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
                         value = !value;

                 return value;
         }

_gpiod_get_raw_value() in turn calls through the get() callback for the
gpiochip implementation, so returning to our get() implementation in
leds-pca955x we find we extract the raw value from hardware:

         static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
         {
                 struct pca955x *pca955x = gpiochip_get_data(gc);
                 struct pca955x_led *led = &pca955x->leds[offset];
                 u8 reg = pca955x_read_input(pca955x->client, led->led_num / 8);

                 return !!(reg & (1 << (led->led_num % 8)));
         }

This behaviour is not symmetric with that of set(), where the val is
inverted by the driver.

Closing the loop on the GPIO_ACTIVE_LOW inversions,
gpiod_direction_output(), like gpiod_get_value_cansleep(), handles it
for us:

         int gpiod_direction_output(struct gpio_desc *desc, int value)
         {
                  VALIDATE_DESC(desc);
                  if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
                           value = !value;
                  else
                           value = !!value;
                  return _gpiod_direction_output_raw(desc, value);
         }

All-in-all, with a value of 'keep' for default-state property in a
leds-gpio child node, the current state of the hardware will in-fact be
inverted; precisely the opposite of what was intended.

Rework leds-pca955x so that we avoid the incorrect inversion and clarify
the semantics with respect to GPIO.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Joel Stanley <joel@jms.id.au>
Tested-by: Matt Spinler <mspinler@linux.vnet.ibm.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-10-06 21:31:03 +02:00
Cédric Le Goater 1591caf2d5 leds: pca955x: check for I2C errors
This should also allow probing to fail when a pca955x chip is not
found on a I2C bus.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-08-30 21:37:53 +02:00
Jacek Anaszewski 390c97dc6e leds: pca955x: Prevent crippled LED device name
In case platform data provided empty LED name string the resulting
LED class device name would be crippled. Use corresponding LED chip
bit in place of "function" segment of LED class device name then to
make the LEDs at least distinguishable.

Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Reported-by: Colin King <colin.king@canonical.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Nate Case <ncase@xes-inc.com>
2017-08-29 21:10:37 +02:00
Cédric Le Goater 561099a1a2 leds: pca955x: add GPIO support
The PCA955x family of chips are I2C LED blinkers whose pins not used
to control LEDs can be used as general purpose I/Os (GPIOs).

The following adds such a support by defining different operation
modes for the pins (See bindings documentation for more details). The
pca955x driver is then extended with a gpio_chip when some of pins are
operating as GPIOs. The default operating mode is to behave as a LED.

The GPIO support is conditioned by CONFIG_LEDS_PCA955X_GPIO.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-08-14 22:22:37 +02:00
Cédric Le Goater 91940bb4ca leds: pca955x: use devm_led_classdev_register
This lets us remove the loop doing the cleanup in case of failure and
also the remove handler of the i2c_driver.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-08-14 22:22:25 +02:00
Cédric Le Goater ed1f4b9676 leds: pca955x: add device tree support
It will be used in a following patch to define different operation
modes for each pin.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-08-14 22:21:14 +02:00
Tin Huynh aace34c0bb leds: pca955x: Correct I2C Functionality
The driver checks an incorrect flag of functionality of adapter.
When a driver requires i2c_smbus_read_byte_data and
i2c_smbus_write_byte_data, it should check I2C_FUNC_SMBUS_BYTE_DATA
instead I2C_FUNC_I2C.
This patch fixes the problem.

Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2017-05-22 21:12:44 +02:00
Tin Huynh 44b3e31d54 leds: pca955x: Add ACPI support
This patch enables ACPI support for leds-pca955x driver.

Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-12-02 09:31:50 +01:00
Andrew Lunn c3482b8250 leds: pca955x: Remove work queue
Now the core implements the work queue, remove it from the drivers,
and switch to using brightness_set_blocking op.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Cc: Nate Case <ncase@xes-inc.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-01-04 09:57:33 +01:00
Krzysztof Kozlowski 44ab901f91 leds: Drop owner assignment from i2c_driver
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2015-08-28 14:06:02 +02:00
Jingoo Han 87aae1ea82 leds: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2013-08-26 17:22:11 -07:00
Linus Torvalds e81d372ff9 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds
Pull LED subsystem update from Bryan Wu.

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds: (47 commits)
  leds: leds-lp5521: return an error code on error in probe()
  leds: leds-clevo-mail: Use pr_* instead of printks
  leds: leds-rb532: Fix checkpatch errors
  leds: led-triggers: Fix checkpatch warnings
  leds: ledtrig-backlight: Fix checkpatch error
  leds: leds-wrap: Use <linux/io.h> instead of <asm/io.h>
  leds: leds-wm8350: Use dev_err instead of printk
  leds: leds-pwm: Fix checkpatch warning
  leds: leds-pca955x: Use dev_info instead of printk
  leds: leds-net48xx: Use linux/io.h instead of asm/io.h
  leds: leds-lt3593: Fix checkpatch warnings
  leds: leds-gpio: Use dev_info instead of printk
  leds: leds-da903x: Fix checkpatch error and warnings
  leds: leds-bd2802: Fix checkpatch warnings
  leds: leds-adp5520: Fix checkpatch warnings
  leds: led-class: Fix checkpatch warning
  leds: leds-ns2: use devm_gpio_request_one
  leds: leds-lt3593: use devm_gpio_request_one
  leds: leds-gpio: use devm_gpio_request_one
  leds: lp3944: Fix return value
  ...
2012-12-15 12:52:42 -08:00
Bill Pemberton 678e8a6be9 leds: remove use of __devexit
CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jan-Simon Moeller <jansimon.moeller@gmx.de>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:35:06 -08:00
Bill Pemberton 98ea1ea20c leds: remove use of __devinit
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jan-Simon Moeller <jansimon.moeller@gmx.de>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:34:57 -08:00
Bill Pemberton df07cf8126 leds: remove use of __devexit_p
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jan-Simon Moeller <jansimon.moeller@gmx.de>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28 12:33:20 -08:00
Sachin Kamat b40b0c17d7 leds: leds-pca955x: Use dev_info instead of printk
Fixes the following checkpatch warning:
WARNING: Prefer netdev_info(netdev, ... then dev_info(dev, ...
then pr_info(...  to printk(KERN_INFO ...

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2012-11-27 14:49:28 -08:00
Bryan Wu 73759f6ab3 leds: convert PCA955x LED driver to devm_kzalloc() and cleanup error exit path
Cc: Nate Case <ncase@xes-inc.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
2012-07-24 07:52:39 +08:00
Alexander Stein e7e11d8ba8 drivers/leds/leds-pca955x.c: fix race condition while setting brightness on several LEDs
When issuing the following command:

  for I in 0 1 2 3 4 5 6 7; do
    echo 0 > /sys/class/leds/pca955x\:${I}/brightness;
  done

It is possible that all the pca955x_read_ls calls are done sequentially
before any pca955x_write_ls call is done.  This updates the LS only to
the last LED update in its set.

Fix this by using a global lock for the pca995x device during
pca955x_led_work.  Also used a struct for shared data betreen all LEDs.

[akpm@linux-foundation.org: revert unintentional rename of pca955x_ledsel()]
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:32 -07:00
Axel Lin 09a0d183ef leds: convert led i2c drivers to module_i2c_driver
Factor out some boilerplate code for i2c driver registration
into module_i2c_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Haojian Zhuang <hzhuang1@marvell.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Michael Hennerich <hennerich@blackfin.uclinux.org>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:48 -08:00
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Sven Wegener 0adaf6e4c2 leds: leds-pca955x - Mark pca955x_led_set() static
Mark pca955x_led_set() as static

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2008-10-20 22:57:56 +01:00
Sven Wegener 95bf14bff5 leds-pca955x: add proper error handling and fix bogus memory handling
Check the return value of led_classdev_register and unregister all
registered devices, if registering one device fails.  Also the dynamic
memory handling is totally bogus.  You can't allocate multiple chunks via
kzalloc() and expect them to be in order later.  I wonder how this ever
worked.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Acked-by: Nate Case <ncase@xes-inc.com>
Tested-by: Nate Case <ncase@xes-inc.com>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-03 18:22:18 -07:00
Nate Case f46e9203d9 leds: Add support for Philips PCA955x I2C LED drivers
This driver supports the PCA9550, PCA9551, PCA9552, and PCA9553
LED driver chips.

Signed-off-by: Nate Case <ncase@xes-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
2008-07-23 09:49:56 +01:00