diff options
author | David Brownell <dbrownell@users.sourceforge.net> | 2009-01-07 01:42:26 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-07 02:59:25 +0300 |
commit | cabb3fc4bd1628c37c37e054960eb3e4bf30dc26 (patch) | |
tree | db8acce21cc4c9762da5f815779ec702f5a59c0c /drivers/gpio | |
parent | ba6c4033b9db22cb54e7e03dae5b624b7b0ffaf9 (diff) | |
download | linux-cabb3fc4bd1628c37c37e054960eb3e4bf30dc26.tar.xz |
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: 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>
Diffstat (limited to 'drivers/gpio')
-rw-r--r-- | drivers/gpio/twl4030-gpio.c | 54 |
1 files changed, 23 insertions, 31 deletions
diff --git a/drivers/gpio/twl4030-gpio.c b/drivers/gpio/twl4030-gpio.c index 37d3eec8730a..afad14792141 100644 --- a/drivers/gpio/twl4030-gpio.c +++ b/drivers/gpio/twl4030-gpio.c @@ -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; |