today, i want to the beagleboard-xm support touchscreen,i refer to some blog,but now ,linux kernel start ,then error with touchscreen ,the ads7864 is the controller of touchscreen.
the error is :
9.669769]
[ 9.674102] ads7846 spi3.0: touchscreen, irq 322
[ 9.679046] ads7846 spi3.0: no device detected, test read result was 0x00000000
[ 9.687042] input: twl4030_pwrbutton as /devices/platform/i2c_omap.1/i2c-1/1-0049/twl4030_pwrbutton/input/input1
[ 9.697753] i2c /dev entries driver
[ 9.701934] Linux video capture interface: v2.00
[ 9.706909] omap-iommu omap-iommu.0: isp: version 1.1
this error in ads7864_probe function in linux source :
/* take a first sample, leaving nPENIRQ active and vREF off; avoid
* the touchscreen, in case it's not connected.
*/
/* err = ads7846_read12_ser(&spi->dev,
READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON);
/* if sample is all 0's or all 1's then there is no device on spi */
/* if ( (err == 0x000) || (err == 0xfff)) {
dev_info(&spi->dev, "no device detected, test read result was 0x%08X\n", err);
err = -ENODEV;
goto err_free_irq;
}
....
so i want to some advices to solve it who had done it before .
thank you ....
