/*
* __device_refresh_sync - request a synchronous refresh from the
* accelerometer. We wait for the refresh to complete. Returns zero if
* successful and nonzero on error. Callers must hold hdaps_sem.
*/
static int __device_refresh_sync(void)
{
__device_refresh();
return __wait_latch(0x1604, STATE_FRESH);
}
/*
* hdaps_device_init - initialize the accelerometer. Returns zero on success
* and negative error code on failure. Can sleep.
*/
static int hdaps_device_init(void)
{
int total, ret = -ENXIO;
down(&hdaps_sem);
outb(0x13, 0x1610);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
/*
* Most ThinkPads return 0x01.
*
* Others--namely the R50p, T41p, and T42p--return 0x03. These laptops
* have "inverted" axises.
*
* The 0x02 value occurs when the chip has been previously initialized.
*/
if (__check_latch(0x1611, 0x03) &&
__check_latch(0x1611, 0x02) &&
__check_latch(0x1611, 0x01))
goto out;
printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
__get_latch(0x1611));
outb(0x17, 0x1610);
outb(0x81, 0x1611);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
if (__wait_latch(0x1611, 0x00))
goto out;
if (__wait_latch(0x1612, 0x60))
goto out;
if (__wait_latch(0x1613, 0x00))
goto out;
outb(0x14, 0x1610);
outb(0x01, 0x1611);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
outb(0x10, 0x1610);
outb(0xc8, 0x1611);
outb(0x00, 0x1612);
outb(0x02, 0x1613);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
if (__device_refresh_sync())
goto out;
if (__wait_latch(0x1611, 0x00))
goto out;
/* we have done our dance, now let's wait for the applause */
for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
int x, y;
/* a read of the device helps push it into action */
__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
if (!__wait_latch(0x1611, 0x02)) {
ret = 0;
break;
}
msleep(INIT_WAIT_MSECS);
}
out:
up(&hdaps_sem);
return ret;
}
static int hdaps_device_init(void)
{
int total, ret = -ENXIO;
mutex_lock(&hdaps_mtx);
outb(0x13, 0x1610);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
if (__check_latch(0x1611, 0x03) &&
__check_latch(0x1611, 0x02) &&
__check_latch(0x1611, 0x01))
goto out;
printk(KERN_DEBUG "hdaps: initial latch check good (0x%02x).\n",
__get_latch(0x1611));
outb(0x17, 0x1610);
outb(0x81, 0x1611);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
if (__wait_latch(0x1611, 0x00))
goto out;
if (__wait_latch(0x1612, 0x60))
goto out;
if (__wait_latch(0x1613, 0x00))
goto out;
outb(0x14, 0x1610);
outb(0x01, 0x1611);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
outb(0x10, 0x1610);
outb(0xc8, 0x1611);
outb(0x00, 0x1612);
outb(0x02, 0x1613);
outb(0x01, 0x161f);
if (__wait_latch(0x161f, 0x00))
goto out;
if (__device_refresh_sync())
goto out;
if (__wait_latch(0x1611, 0x00))
goto out;
for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
int x, y;
__hdaps_read_pair(HDAPS_PORT_XPOS, HDAPS_PORT_YPOS, &x, &y);
if (!__wait_latch(0x1611, 0x02)) {
ret = 0;
break;
}
msleep(INIT_WAIT_MSECS);
}
out:
mutex_unlock(&hdaps_mtx);
return ret;
}
