Commit 5b327edf authored by Rabin Vincent's avatar Rabin Vincent Committed by Russell King
Browse files

ARM: 6148/1: nomadik-gpio: add function to configure pullup/pulldown 



Cc: Alessandro Rubini <rubini@unipv.it>
Acked-by: default avatarLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: default avatarRabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 6647c6c0

arch/arm/plat-nomadik/gpio.c

+48 −0
Original line number Diff line number Diff line
@@ -46,6 +46,54 @@ struct nmk_gpio_chip { 
	u32 edge_falling;

};



static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,

				unsigned offset, enum nmk_gpio_pull pull)

{

	u32 bit = 1 << offset;

	u32 pdis;



	pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS);

	if (pull == NMK_GPIO_PULL_NONE)

		pdis |= bit;

	else

		pdis &= ~bit;

	writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);



	if (pull == NMK_GPIO_PULL_UP)

		writel(bit, nmk_chip->addr + NMK_GPIO_DATS);

	else if (pull == NMK_GPIO_PULL_DOWN)

		writel(bit, nmk_chip->addr + NMK_GPIO_DATC);

}



/**

 * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio

 * @gpio: pin number

 * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE

 *

 * Enables/disables pull up/down on a specified pin.  This only takes effect if

 * the pin is configured as an input (either explicitly or by the alternate

 * function).

 *

 * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is

 * configured as an input.  Otherwise, due to the way the controller registers

 * work, this function will change the value output on the pin.

 */

int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull)

{

	struct nmk_gpio_chip *nmk_chip;

	unsigned long flags;



	nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));

	if (!nmk_chip)

		return -EINVAL;



	spin_lock_irqsave(&nmk_chip->lock, flags);

	__nmk_gpio_set_pull(nmk_chip, gpio - nmk_chip->chip.base, pull);

	spin_unlock_irqrestore(&nmk_chip->lock, flags);



	return 0;

}



/* Mode functions */

int nmk_gpio_set_mode(int gpio, int gpio_mode)

{

arch/arm/plat-nomadik/include/plat/gpio.h

+8 −0
Original line number Diff line number Diff line
@@ -55,6 +55,14 @@ 
#define NMK_GPIO_ALT_B	2

#define NMK_GPIO_ALT_C	(NMK_GPIO_ALT_A | NMK_GPIO_ALT_B)



/* Pull up/down values */

enum nmk_gpio_pull {

	NMK_GPIO_PULL_NONE,

	NMK_GPIO_PULL_UP,

	NMK_GPIO_PULL_DOWN,

};



extern int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull);

extern int nmk_gpio_set_mode(int gpio, int gpio_mode);

extern int nmk_gpio_get_mode(int gpio);