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authorDavid Brownell <dbrownell@users.sourceforge.net>2009-01-07 01:42:26 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2009-01-07 02:59:25 +0300
commitcabb3fc4bd1628c37c37e054960eb3e4bf30dc26 (patch)
treedb8acce21cc4c9762da5f815779ec702f5a59c0c /drivers/gpio
parentba6c4033b9db22cb54e7e03dae5b624b7b0ffaf9 (diff)
downloadlinux-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.c54
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;