Commit cabb3fc4 authored by David Brownell's avatar David Brownell Committed by Linus Torvalds
Browse files

twl4030-gpio: cleanup debounce 



Provide a static debounce configuration mechanism for twl4030 GPIOs,
replacing the previous dynamic one.  The single user of that mechanism was
for MMC card detect debouncing.

Boards can provide a bitmask saying which GPIOs to debounce (30 msec).
It's always enabled for pins with the MMC card-detect/VMMCx link active,
so most boards won't need to set the debounce mask.

This is a net code shrink, including runtime footprint.

Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ba6c4033

drivers/gpio/twl4030-gpio.c

+23 −31
Original line number Diff line number Diff line
@@ -202,37 +202,6 @@ static int twl4030_get_gpio_datain(int gpio) 
	return ret;

}



/*

 * Configure debounce timing value for a GPIO pin on TWL4030

 */

int twl4030_set_gpio_debounce(int gpio, int enable)

{

	u8 d_bnk = gpio >> 3;

	u8 d_msk = BIT(gpio & 0x7);

	u8 reg = 0;

	u8 base = 0;

	int ret = 0;



	if (unlikely((gpio >= TWL4030_GPIO_MAX)

		|| !(gpio_usage_count & BIT(gpio))))

		return -EPERM;



	base = REG_GPIO_DEBEN1 + d_bnk;

	mutex_lock(&gpio_lock);

	ret = gpio_twl4030_read(base);

	if (ret >= 0) {

		if (enable)

			reg = ret | d_msk;

		else

			reg = ret & ~d_msk;



		ret = gpio_twl4030_write(base, reg);

	}

	mutex_unlock(&gpio_lock);

	return ret;

}

EXPORT_SYMBOL(twl4030_set_gpio_debounce);



/*----------------------------------------------------------------------*/



static int twl_request(struct gpio_chip *chip, unsigned offset)
@@ -405,6 +374,23 @@ static int __devinit gpio_twl4030_pulls(u32 ups, u32 downs) 
				REG_GPIOPUPDCTR1, 5);

}



static int __devinit gpio_twl4030_debounce(u32 debounce, u8 mmc_cd)

{

	u8		message[4];



	/* 30 msec of debouncing is always used for MMC card detect,

	 * and is optional for everything else.

	 */

	message[1] = (debounce & 0xff) | (mmc_cd & 0x03);

	debounce >>= 8;

	message[2] = (debounce & 0xff);

	debounce >>= 8;

	message[3] = (debounce & 0x03);



	return twl4030_i2c_write(TWL4030_MODULE_GPIO, message,

				REG_GPIO_DEBEN1, 3);

}



static int gpio_twl4030_remove(struct platform_device *pdev);



static int __devinit gpio_twl4030_probe(struct platform_device *pdev)
@@ -439,6 +425,12 @@ no_irqs: 
				pdata->pullups, pdata->pulldowns,

				ret);



	ret = gpio_twl4030_debounce(pdata->debounce, pdata->mmc_cd);

	if (ret)

		dev_dbg(&pdev->dev, "debounce %.03x %.01x --> %d\n",

				pdata->debounce, pdata->mmc_cd,

				ret);



	twl_gpiochip.base = pdata->gpio_base;

	twl_gpiochip.ngpio = TWL4030_GPIO_MAX;

	twl_gpiochip.dev = &pdev->dev;

include/linux/i2c/twl4030.h

+3 −6
Original line number Diff line number Diff line
@@ -234,6 +234,9 @@ struct twl4030_gpio_platform_data { 
	/* gpio-n should control VMMC(n+1) if BIT(n) in mmc_cd is set */

	u8		mmc_cd;



	/* if BIT(N) is set, or VMMC(n+1) is linked, debounce GPIO-N */

	u32		debounce;



	/* For gpio-N, bit (1 << N) in "pullups" is set if that pullup

	 * should be enabled.  Else, if that bit is set in "pulldowns",

	 * that pulldown is enabled.  Don't waste power by letting any
@@ -307,12 +310,6 @@ int twl4030_sih_setup(int module); 
#define TWL4030_VAUX3_DEV_GRP		0x1F

#define TWL4030_VAUX3_DEDICATED		0x22



/*

 * Exported TWL4030 GPIO APIs

 *

 * WARNING -- use standard GPIO and IRQ calls instead; these will vanish.

 */

int twl4030_set_gpio_debounce(int gpio, int enable);



#if defined(CONFIG_TWL4030_BCI_BATTERY) || \

	defined(CONFIG_TWL4030_BCI_BATTERY_MODULE)

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