forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

twl4030-gpio: cleanup debounce

Browse source 
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: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Brownell 2009-01-06 14:42:26 -08:00 • committed by Linus Torvalds
commit cabb3fc4bd
2 changed files with 26 additions and 37 deletions
Download patch file Download diff file Expand all files Collapse all files

54
drivers/gpio/twl4030-gpio.c
View file

@ -202,37 +202,6 @@ static int twl4030_get_gpio_datain(int gpio)
return ret; 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) 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); 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 gpio_twl4030_remove(struct platform_device *pdev);
static int __devinit gpio_twl4030_probe(struct platform_device *pdev) static int __devinit gpio_twl4030_probe(struct platform_device *pdev)
@ -439,6 +425,12 @@ no_irqs:
pdata->pullups, pdata->pulldowns, pdata->pullups, pdata->pulldowns,
ret); 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.base = pdata->gpio_base;
twl_gpiochip.ngpio = TWL4030_GPIO_MAX; twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
twl_gpiochip.dev = &pdev->dev; twl_gpiochip.dev = &pdev->dev;

9
include/linux/i2c/twl4030.h
View file

@ -234,6 +234,9 @@ struct twl4030_gpio_platform_data {
/* gpio-n should control VMMC(n+1) if BIT(n) in mmc_cd is set */ /* gpio-n should control VMMC(n+1) if BIT(n) in mmc_cd is set */
u8 mmc_cd; 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 /* For gpio-N, bit (1 << N) in "pullups" is set if that pullup
* should be enabled. Else, if that bit is set in "pulldowns", * should be enabled. Else, if that bit is set in "pulldowns",
* that pulldown is enabled. Don't waste power by letting any * 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_DEV_GRP 0x1F
#define TWL4030_VAUX3_DEDICATED 0x22 #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) || \ #if defined(CONFIG_TWL4030_BCI_BATTERY) || \
defined(CONFIG_TWL4030_BCI_BATTERY_MODULE) defined(CONFIG_TWL4030_BCI_BATTERY_MODULE)