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  1. Dec 22, 2017
    • Rasmus Villemoes's avatar
      gpio: reduce descriptor validation code size · a746a232
      Rasmus Villemoes authored 
      

While we do need macros to be able to return from the "calling"
function, we can still factor the checks done by the VALIDATE_DESC*
macros into a real helper function. This reduces the backslashtitis,
avoids duplicating the logic in the two macros and saves about 1K of
generated code:

$ scripts/bloat-o-meter drivers/gpio/gpiolib.o.{0,1}
add/remove: 1/0 grow/shrink: 0/15 up/down: 104/-1281 (-1177)
Function                                     old     new   delta
validate_desc                                  -     104    +104
gpiod_set_value                              192     135     -57
gpiod_set_raw_value                          125      67     -58
gpiod_direction_output                       412     351     -61
gpiod_set_value_cansleep                     150      70     -80
gpiod_set_raw_value_cansleep                 132      52     -80
gpiod_get_raw_value                          139      54     -85
gpiod_set_debounce                           226     140     -86
gpiod_direction_output_raw                   124      38     -86
gpiod_get_value                              161      74     -87
gpiod_cansleep                               126      39     -87
gpiod_get_raw_value_cansleep                 130      39     -91
gpiod_get_value_cansleep                     152      59     -93
gpiod_is_active_low                          128      33     -95
gpiod_request                                299     184    -115
gpiod_direction_input                        386     266    -120
Total: Before=25460, After=24283, chg -4.62%

Signed-off-by: default avatarRasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: default avatarVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      a746a232
  3. Dec 21, 2017
  5. Dec 20, 2017
  7. Dec 08, 2017
    • Bartosz Golaszewski's avatar
      gpio: mockup: fix a return value check · c4b54e13
      Bartosz Golaszewski authored 
      

The return value of platform_device_register_resndata() on error is
an error code converted to pointer with ERR_PTR(), not NULL.

Check the return value correctly.

Fixes: 8a39f597 ("gpio: mockup: rework device probing")
Signed-off-by: default avatarBartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      c4b54e13
    • Linus Walleij's avatar
      w1: w1-gpio: Convert to use GPIO descriptors · e0fc62a6
      Linus Walleij authored 
      

The w1 master driver includes a complete open drain emulation
reimplementation among other things.

This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.

When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.

As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.

w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.

The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.

To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.

We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.

Acked-by: default avatarEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      e0fc62a6
  9. Dec 07, 2017
  11. Dec 03, 2017