[PATCH 4/4] gpio/nomadik: add function to read GPIO pull down status

From: Linus Walleij
Date: Tue May 24 2011 - 17:07:36 EST


From: Rickard Andersson <rickard.andersson@xxxxxxxxxxxxxx>

Signed-off-by: Rickard Andersson <rickard.andersson@xxxxxxxxxxxxxx>
Reviewed-by: Martin Persson <martin.persson@xxxxxxxxxxxxxx>
[Split off from larger patch]
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
arch/arm/plat-nomadik/include/plat/gpio.h | 2 +
drivers/gpio/gpio-nomadik.c | 34 +++++++++++++++++++++++++---
2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/arch/arm/plat-nomadik/include/plat/gpio.h b/arch/arm/plat-nomadik/include/plat/gpio.h
index 1b9f6f0..ea19a5b 100644
--- a/arch/arm/plat-nomadik/include/plat/gpio.h
+++ b/arch/arm/plat-nomadik/include/plat/gpio.h
@@ -78,6 +78,8 @@ extern int nmk_gpio_get_mode(int gpio);
extern void nmk_gpio_wakeups_suspend(void);
extern void nmk_gpio_wakeups_resume(void);

+extern void nmk_gpio_read_pull(int gpio_bank, u32 *pull_up);
+
/*
* Platform data to register a block: only the initial gpio/irq number.
*/
diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c
index 3802047..4961ef9 100644
--- a/drivers/gpio/gpio-nomadik.c
+++ b/drivers/gpio/gpio-nomadik.c
@@ -57,6 +57,7 @@ struct nmk_gpio_chip {
u32 fwimsc;
u32 slpm;
u32 enabled;
+ u32 pull_up;
};

static struct nmk_gpio_chip *
@@ -103,16 +104,22 @@ static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
u32 pdis;

pdis = readl(nmk_chip->addr + NMK_GPIO_PDIS);
- if (pull == NMK_GPIO_PULL_NONE)
+ if (pull == NMK_GPIO_PULL_NONE) {
pdis |= bit;
- else
+ nmk_chip->pull_up &= ~bit;
+ } else {
pdis &= ~bit;
+ }
+
writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);

- if (pull == NMK_GPIO_PULL_UP)
+ if (pull == NMK_GPIO_PULL_UP) {
+ nmk_chip->pull_up |= bit;
writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
- else if (pull == NMK_GPIO_PULL_DOWN)
+ } else if (pull == NMK_GPIO_PULL_DOWN) {
+ nmk_chip->pull_up &= ~bit;
writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
+ }
}

static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip,
@@ -921,6 +928,25 @@ void nmk_gpio_wakeups_resume(void)
}
}

+/*
+ * Read the pull up/pull down status.
+ * A bit set in 'pull_up' means that pull up
+ * is selected if pull is enabled in PDIS register.
+ * Note: only pull up/down set via this driver can
+ * be detected due to HW limitations.
+ */
+void nmk_gpio_read_pull(int gpio_bank, u32 *pull_up)
+{
+ if (gpio_bank < NUM_BANKS) {
+ struct nmk_gpio_chip *chip = nmk_gpio_chips[gpio_bank];
+
+ if (!chip)
+ return;
+
+ *pull_up = chip->pull_up;
+ }
+}
+
static int __devinit nmk_gpio_probe(struct platform_device *dev)
{
struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
--
1.7.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/