pinctrl: add pinconf-generic define for a pin-default pull

There exist controllers that don't support to set the pull to up or down
separately but instead automatically set the pull direction based on
embedded knowledge inside the controller, for example depending on the
selected mux function of the pin.

Therefore this patch adds another config option to use this default
pull-state for a pin where it is not possible to know or decide if the
pin will be pulled up or down.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/pinconf-generic.c b/drivers/pinctrl/pinconf-generic.c
index c3ce85b0888fb3ab018708a62c6978c252599612..794dad7d68d8ac1adec371c4a71a9f789e4d414e 100644 (file)
--- a/drivers/pinctrl/pinconf-generic.c
+++ b/drivers/pinctrl/pinconf-generic.c
@@ -41,6 +41,8 @@ static struct pin_config_item conf_items[] = {
        PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL),
        PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL),
        PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL),
+       PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
+                               "input bias pull to pin specific state", NULL),
        PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL),
        PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL),
        PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL),

diff --git a/include/linux/pinctrl/pinconf-generic.h b/include/linux/pinctrl/pinconf-generic.h
index ac05b3cfeacc0c0ae7ca4f708385ae01d070616d..d414a7729424a94780b936edc557581cf23fdc22 100644 (file)
--- a/include/linux/pinctrl/pinconf-generic.h
+++ b/include/linux/pinctrl/pinconf-generic.h
@@ -40,6 +40,10 @@
  * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
  *     impedance to GROUND). If the argument is != 0 pull-down is enabled,
  *     if it is 0, pull-down is disabled.
+ * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
+ *     on embedded knowledge of the controller, like current mux function.
+ *     If the argument is != 0 pull up/down is enabled, if it is 0,
+ *     the pull is disabled.
  * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
  *     low, this is the most typical case and is typically achieved with two
  *     active transistors on the output. Setting this config will enable
@@ -86,6 +90,7 @@ enum pin_config_param {
        PIN_CONFIG_BIAS_BUS_HOLD,
        PIN_CONFIG_BIAS_PULL_UP,
        PIN_CONFIG_BIAS_PULL_DOWN,
+       PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
        PIN_CONFIG_DRIVE_PUSH_PULL,
        PIN_CONFIG_DRIVE_OPEN_DRAIN,
        PIN_CONFIG_DRIVE_OPEN_SOURCE,