基于beagleboard-xm的触摸屏移栽和Qt4.6.2移植

//by gzz 
#ifdef CONFIG_TOUCHSCREEN_ADS7846

#define OMAP3_BEAGLE_TS_GPIO       162 /* gpio_133 for v1.0 */

#include <plat/mcspi.h>
#include <linux/spi/spi.h>
#include <linux/spi/ads7846.h>     //for ads7864 touchscreen  

static struct omap2_mcspi_device_config ads7846_mcspi_config = {
        .turbo_mode     = 0,
        .single_channel = 1,    /* 0: slave, 1: master */
};

static int ads7846_get_pendown_state(void)
{
        return !gpio_get_value(OMAP3_BEAGLE_TS_GPIO);
}

struct ads7846_platform_data ads7846_config = {
        .x_max                  = 0x0fff,
        .y_max                  = 0x0fff,
        .x_plate_ohms           = 180,
        .pressure_max           = 255,
        .debounce_max           = 10,
        .debounce_tol           = 3,
        .debounce_rep           = 1,
        .get_pendown_state      = ads7846_get_pendown_state,
        .keep_vref_on           = 1,
        .settle_delay_usecs     = 150,
        .wakeup					= true,
};

struct spi_board_info omap3beagle_spi_board_info[] = {
        [0] = {
                .modalias               = "ads7846",
                .bus_num                = 3,
                .chip_select            = 0,
                .max_speed_hz           = 1500000,
                .controller_data        = &ads7846_mcspi_config,
                .irq                    = OMAP_GPIO_IRQ(OMAP3_BEAGLE_TS_GPIO),
                .platform_data          = &ads7846_config,
        },
};


static void ads7846_dev_init(void)
{
    printk("Initialize ads7846 touch screen controller\n");

        if (gpio_request(OMAP3_BEAGLE_TS_GPIO, "ADS7846 pendown") < 0)
                printk(KERN_ERR "can't get ads7846 pen down GPIO\n");

        gpio_direction_input(OMAP3_BEAGLE_TS_GPIO);

        omap_set_gpio_debounce(OMAP3_BEAGLE_TS_GPIO, 1);
        omap_set_gpio_debounce_time(OMAP3_BEAGLE_TS_GPIO, 0xa);
}

#else
static inline void __init ads7846_dev_init(void) { return; }
#endif