diff options
author | Eric Miao <eric.y.miao@gmail.com> | 2008-09-10 16:06:15 (GMT) |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-09-17 16:33:37 (GMT) |
commit | 6ae19b04ab41a4db0f0c48ec0b78950f6b028823 (patch) | |
tree | 9a9c38bc7be0741b19abbb345f5bd001bfc0ab97 | |
parent | adee14b2e1557d0a8559f29681732d05a89dfc35 (diff) | |
download | linux-6ae19b04ab41a4db0f0c48ec0b78950f6b028823.tar.xz |
Input: ads7846 - introduce .gpio_pendown to get pendown state
The GPIO connected to ADS7846 nPENIRQ signal is usually used to get
the pendown state as well. Introduce a .gpio_pendown, and use this
to decide the pendown state if .get_pendown_state is NULL.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
-rw-r--r-- | drivers/input/touchscreen/ads7846.c | 68 | ||||
-rw-r--r-- | include/linux/spi/ads7846.h | 3 |
2 files changed, 57 insertions, 14 deletions
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c index ce6f48c..8583c76 100644 --- a/drivers/input/touchscreen/ads7846.c +++ b/drivers/input/touchscreen/ads7846.c @@ -24,6 +24,7 @@ #include <linux/input.h> #include <linux/interrupt.h> #include <linux/slab.h> +#include <linux/gpio.h> #include <linux/spi/spi.h> #include <linux/spi/ads7846.h> #include <asm/irq.h> @@ -116,6 +117,7 @@ struct ads7846 { void *filter_data; void (*filter_cleanup)(void *data); int (*get_pendown_state)(void); + int gpio_pendown; }; /* leave chip selected when we're done, for quicker re-select? */ @@ -491,6 +493,14 @@ static struct attribute_group ads784x_attr_group = { /*--------------------------------------------------------------------------*/ +static int get_pendown_state(struct ads7846 *ts) +{ + if (ts->get_pendown_state) + return ts->get_pendown_state(); + + return !gpio_get_value(ts->gpio_pendown); +} + /* * PENIRQ only kicks the timer. The timer only reissues the SPI transfer, * to retrieve touchscreen status. @@ -550,7 +560,7 @@ static void ads7846_rx(void *ads) */ if (ts->penirq_recheck_delay_usecs) { udelay(ts->penirq_recheck_delay_usecs); - if (!ts->get_pendown_state()) + if (!get_pendown_state(ts)) Rt = 0; } @@ -677,7 +687,7 @@ static enum hrtimer_restart ads7846_timer(struct hrtimer *handle) spin_lock_irq(&ts->lock); - if (unlikely(!ts->get_pendown_state() || + if (unlikely(!get_pendown_state(ts) || device_suspended(&ts->spi->dev))) { if (ts->pendown) { struct input_dev *input = ts->input; @@ -716,7 +726,7 @@ static irqreturn_t ads7846_irq(int irq, void *handle) unsigned long flags; spin_lock_irqsave(&ts->lock, flags); - if (likely(ts->get_pendown_state())) { + if (likely(get_pendown_state(ts))) { if (!ts->irq_disabled) { /* The ARM do_simple_IRQ() dispatcher doesn't act * like the other dispatchers: it will report IRQs @@ -806,6 +816,36 @@ static int ads7846_resume(struct spi_device *spi) return 0; } +static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts) +{ + struct ads7846_platform_data *pdata = spi->dev.platform_data; + int err; + + /* REVISIT when the irq can be triggered active-low, or if for some + * reason the touchscreen isn't hooked up, we don't need to access + * the pendown state. + */ + if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) { + dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); + return -EINVAL; + } + + if (pdata->get_pendown_state) { + ts->get_pendown_state = pdata->get_pendown_state; + return 0; + } + + err = gpio_request(pdata->gpio_pendown, "ads7846_pendown"); + if (err) { + dev_err(&spi->dev, "failed to request pendown GPIO%d\n", + pdata->gpio_pendown); + return err; + } + + ts->gpio_pendown = pdata->gpio_pendown; + return 0; +} + static int __devinit ads7846_probe(struct spi_device *spi) { struct ads7846 *ts; @@ -833,15 +873,6 @@ static int __devinit ads7846_probe(struct spi_device *spi) return -EINVAL; } - /* REVISIT when the irq can be triggered active-low, or if for some - * reason the touchscreen isn't hooked up, we don't need to access - * the pendown state. - */ - if (pdata->get_pendown_state == NULL) { - dev_dbg(&spi->dev, "no get_pendown_state function?\n"); - return -EINVAL; - } - /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except * that even if the hardware can do that, the SPI controller driver * may not. So we stick to very-portable 8 bit words, both RX and TX. @@ -893,7 +924,10 @@ static int __devinit ads7846_probe(struct spi_device *spi) ts->filter_data = ts; } else ts->filter = ads7846_no_filter; - ts->get_pendown_state = pdata->get_pendown_state; + + err = setup_pendown(spi, ts); + if (err) + goto err_cleanup_filter; if (pdata->penirq_recheck_delay_usecs) ts->penirq_recheck_delay_usecs = @@ -1085,7 +1119,7 @@ static int __devinit ads7846_probe(struct spi_device *spi) spi->dev.driver->name, ts)) { dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); err = -EBUSY; - goto err_cleanup_filter; + goto err_free_gpio; } err = ads784x_hwmon_register(spi, ts); @@ -1116,6 +1150,9 @@ static int __devinit ads7846_probe(struct spi_device *spi) ads784x_hwmon_unregister(spi, ts); err_free_irq: free_irq(spi->irq, ts); + err_free_gpio: + if (ts->gpio_pendown != -1) + gpio_free(ts->gpio_pendown); err_cleanup_filter: if (ts->filter_cleanup) ts->filter_cleanup(ts->filter_data); @@ -1140,6 +1177,9 @@ static int __devexit ads7846_remove(struct spi_device *spi) /* suspend left the IRQ disabled */ enable_irq(ts->spi->irq); + if (ts->gpio_pendown != -1) + gpio_free(ts->gpio_pendown); + if (ts->filter_cleanup) ts->filter_cleanup(ts->filter_data); diff --git a/include/linux/spi/ads7846.h b/include/linux/spi/ads7846.h index daf7440..05eab2f 100644 --- a/include/linux/spi/ads7846.h +++ b/include/linux/spi/ads7846.h @@ -43,6 +43,9 @@ struct ads7846_platform_data { u16 debounce_tol; /* tolerance used for filtering */ u16 debounce_rep; /* additional consecutive good readings * required after the first two */ + int gpio_pendown; /* the GPIO used to decide the pendown + * state if get_pendown_state == NULL + */ int (*get_pendown_state)(void); int (*filter_init) (struct ads7846_platform_data *pdata, void **filter_data); |