/* Must be called with ts->lock held */
static void ucb1400_ts_start(struct ucb1400_ts *ucb)
{
/* Tell IRQ thread that it may poll the device. */
ucb->stopped = false;
mb();
ucb1400_ts_mode_int(ucb);
ucb1400_ts_irq_enable(ucb);
enable_irq(ucb->irq);
}
/*
* A restriction with interrupts exists when using the ucb1400, as
* the codec read/write routines may sleep while waiting for codec
* access completion and uses semaphores for access control to the
* AC97 bus. Therefore the driver is forced to use threaded interrupt
* handler.
*/
static irqreturn_t ucb1400_irq(int irqnr, void *devid)
{
struct ucb1400_ts *ucb = devid;
unsigned int x, y, p;
bool penup;
if (unlikely(irqnr != ucb->irq))
return IRQ_NONE;
ucb1400_clear_pending_irq(ucb);
/* Start with a small delay before checking pendown state */
msleep(UCB1400_TS_POLL_PERIOD);
while (!ucb->stopped && !(penup = ucb1400_ts_pen_up(ucb))) {
ucb1400_adc_enable(ucb->ac97);
x = ucb1400_ts_read_xpos(ucb);
y = ucb1400_ts_read_ypos(ucb);
p = ucb1400_ts_read_pressure(ucb);
ucb1400_adc_disable(ucb->ac97);
ucb1400_ts_report_event(ucb->ts_idev, p, x, y);
wait_event_timeout(ucb->ts_wait, ucb->stopped,
msecs_to_jiffies(UCB1400_TS_POLL_PERIOD));
}
ucb1400_ts_event_release(ucb->ts_idev);
if (!ucb->stopped) {
/* Switch back to interrupt mode. */
ucb1400_ts_mode_int(ucb);
ucb1400_ts_irq_enable(ucb);
}
return IRQ_HANDLED;
}
static int ucb1400_ts_thread(void *_ucb)
{
struct ucb1400 *ucb = _ucb;
struct task_struct *tsk = current;
int valid = 0;
struct sched_param param = { .sched_priority = 1 };
sched_setscheduler(tsk, SCHED_FIFO, ¶m);
set_freezable();
while (!kthread_should_stop()) {
unsigned int x, y, p;
long timeout;
unsigned int i;
ucb->ts_restart = 0;
if (ucb->irq_pending) {
ucb->irq_pending = 0;
ucb1400_handle_pending_irq(ucb);
}
p = 0;
x = 0;
y = 0;
for(i=0; i<8; i++)
{
ucb1400_adc_enable(ucb);
p += ucb1400_ts_read_pressure(ucb);
x += ucb1400_ts_read_xpos(ucb);
y += ucb1400_ts_read_ypos(ucb);
ucb1400_adc_disable(ucb);
udelay(30);
}
x/=i;
y/=i;
p/=i;
/* Switch back to interrupt mode. */
ucb1400_ts_mode_int(ucb);
msleep(10);
if (ucb1400_ts_pen_down(ucb)) {
ucb1400_ts_irq_enable(ucb);
/*
* If we spat out a valid sample set last time,
* spit out a "pen off" sample here.
*/
if (valid) {
ucb1400_ts_event_release(ucb->ts_idev);
valid = 0;
}
timeout = MAX_SCHEDULE_TIMEOUT;
} else {
valid = 1;
ucb1400_ts_evt_add(ucb->ts_idev, p, x, y);
timeout = msecs_to_jiffies(10);
}
wait_event_interruptible_timeout(ucb->ts_wait,
ucb->irq_pending || ucb->ts_restart || kthread_should_stop(),
timeout);
try_to_freeze();
}
/* Send the "pen off" if we are stopping with the pen still active */
if (valid)
ucb1400_ts_event_release(ucb->ts_idev);
ucb->ts_task = NULL;
return 0;
}
/*
* A restriction with interrupts exists when using the ucb1400, as
* the codec read/write routines may sleep while waiting for codec
* access completion and uses semaphores for access control to the
* AC97 bus. A complete codec read cycle could take anywhere from
* 60 to 100uSec so we *definitely* don't want to spin inside the
* interrupt handler waiting for codec access. So, we handle the
* interrupt by scheduling a RT kernel thread to run in process
* context instead of interrupt context.
*/
static irqreturn_t ucb1400_hard_irq(int irqnr, void *devid)
{
struct ucb1400 *ucb = devid;
if (irqnr == ucb->irq) {
disable_irq(ucb->irq);
ucb->irq_pending = 1;
wake_up(&ucb->ts_wait);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static int ucb1400_ts_open(struct input_dev *idev)
{
struct ucb1400 *ucb = input_get_drvdata(idev);
int ret = 0;
BUG_ON(ucb->ts_task);
ucb->ts_task = kthread_run(ucb1400_ts_thread, ucb, "UCB1400_ts");
if (IS_ERR(ucb->ts_task)) {
ret = PTR_ERR(ucb->ts_task);
ucb->ts_task = NULL;
}
return ret;
}
static void ucb1400_ts_close(struct input_dev *idev)
{
struct ucb1400 *ucb = input_get_drvdata(idev);
if (ucb->ts_task)
{
kthread_stop(ucb->ts_task);
while(ucb->ts_task!=NULL) udelay(100);
}
ucb1400_ts_irq_disable(ucb);
ucb1400_reg_write(ucb, UCB_TS_CR, 0);
}
#ifdef CONFIG_PM
static int ucb1400_ts_resume(struct device *dev)
{
struct ucb1400 *ucb = dev_get_drvdata(dev);
if (ucb->ts_task) {
/*
* Restart the TS thread to ensure the
* TS interrupt mode is set up again
* after sleep.
*/
ucb->ts_restart = 1;
wake_up(&ucb->ts_wait);
}
return 0;
}
#else
#define ucb1400_ts_resume NULL
#endif
#ifndef NO_IRQ
#define NO_IRQ 0
#endif
/*
* Try to probe our interrupt, rather than relying on lots of
* hard-coded machine dependencies.
*/
static int ucb1400_detect_irq(struct ucb1400 *ucb)
{
unsigned long mask, timeout;
#if CONFIG_TOUCHSCREEN_UCB1400_IRQ == 0
mask = probe_irq_on();
if (!mask) {
probe_irq_off(mask);
return -EBUSY;
}
/* Enable the ADC interrupt. */
ucb1400_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
ucb1400_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
ucb1400_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb, UCB_IE_CLEAR, 0);
/* Cause an ADC interrupt. */
ucb1400_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
ucb1400_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
/* Wait for the conversion to complete. */
timeout = jiffies + HZ/2;
while (!(ucb1400_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VALID)) {
cpu_relax();
if (time_after(jiffies, timeout)) {
printk(KERN_ERR "ucb1400: timed out in IRQ probe\n");
probe_irq_off(mask);
return -ENODEV;
}
}
ucb1400_reg_write(ucb, UCB_ADC_CR, 0);
/* Disable and clear interrupt. */
ucb1400_reg_write(ucb, UCB_IE_RIS, 0);
ucb1400_reg_write(ucb, UCB_IE_FAL, 0);
ucb1400_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb, UCB_IE_CLEAR, 0);
/* Read triggered interrupt. */
ucb->irq = probe_irq_off(mask);
#else
ucb->irq = CONFIG_TOUCHSCREEN_UCB1400_IRQ;
#endif
if (ucb->irq < 0 || ucb->irq == NO_IRQ)
return -ENODEV;
return 0;
}
static int ucb1400_ts_thread(void *_ucb)
{
struct ucb1400_ts *ucb = _ucb;
struct task_struct *tsk = current;
int valid = 0;
struct sched_param param = { .sched_priority = 1 };
sched_setscheduler(tsk, SCHED_FIFO, ¶m);
set_freezable();
while (!kthread_should_stop()) {
unsigned int x, y, p;
long timeout;
ucb->ts_restart = 0;
if (ucb->irq_pending) {
ucb->irq_pending = 0;
ucb1400_handle_pending_irq(ucb);
}
ucb1400_adc_enable(ucb->ac97);
x = ucb1400_ts_read_xpos(ucb);
y = ucb1400_ts_read_ypos(ucb);
p = ucb1400_ts_read_pressure(ucb);
ucb1400_adc_disable(ucb->ac97);
/* Switch back to interrupt mode. */
ucb1400_ts_mode_int(ucb->ac97);
msleep(10);
if (ucb1400_ts_pen_up(ucb->ac97)) {
ucb1400_ts_irq_enable(ucb->ac97);
/*
* If we spat out a valid sample set last time,
* spit out a "pen off" sample here.
*/
if (valid) {
ucb1400_ts_event_release(ucb->ts_idev);
valid = 0;
}
timeout = MAX_SCHEDULE_TIMEOUT;
} else {
valid = 1;
ucb1400_ts_evt_add(ucb->ts_idev, p, x, y);
timeout = msecs_to_jiffies(10);
}
wait_event_freezable_timeout(ucb->ts_wait,
ucb->irq_pending || ucb->ts_restart ||
kthread_should_stop(), timeout);
}
/* Send the "pen off" if we are stopping with the pen still active */
if (valid)
ucb1400_ts_event_release(ucb->ts_idev);
ucb->ts_task = NULL;
return 0;
}
static irqreturn_t ucb1400_hard_irq(int irqnr, void *devid)
{
struct ucb1400_ts *ucb = devid;
if (irqnr == ucb->irq) {
disable_irq_nosync(ucb->irq);
ucb->irq_pending = 1;
wake_up(&ucb->ts_wait);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static int ucb1400_ts_open(struct input_dev *idev)
{
struct ucb1400_ts *ucb = input_get_drvdata(idev);
int ret = 0;
BUG_ON(ucb->ts_task);
ucb->ts_task = kthread_run(ucb1400_ts_thread, ucb, "UCB1400_ts");
if (IS_ERR(ucb->ts_task)) {
ret = PTR_ERR(ucb->ts_task);
ucb->ts_task = NULL;
}
return ret;
}
static void ucb1400_ts_close(struct input_dev *idev)
{
struct ucb1400_ts *ucb = input_get_drvdata(idev);
if (ucb->ts_task)
kthread_stop(ucb->ts_task);
ucb1400_ts_irq_disable(ucb->ac97);
ucb1400_reg_write(ucb->ac97, UCB_TS_CR, 0);
}
#ifndef NO_IRQ
#define NO_IRQ 0
#endif
static int ucb1400_ts_detect_irq(struct ucb1400_ts *ucb)
{
unsigned long mask, timeout;
mask = probe_irq_on();
/* Enable the ADC interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, UCB_IE_ADC);
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, UCB_IE_ADC);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
/* Cause an ADC interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA);
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
/* Wait for the conversion to complete. */
timeout = jiffies + HZ/2;
while (!(ucb1400_reg_read(ucb->ac97, UCB_ADC_DATA) &
UCB_ADC_DAT_VALID)) {
cpu_relax();
if (time_after(jiffies, timeout)) {
printk(KERN_ERR "ucb1400: timed out in IRQ probe\n");
probe_irq_off(mask);
return -ENODEV;
}
}
ucb1400_reg_write(ucb->ac97, UCB_ADC_CR, 0);
/* Disable and clear interrupt. */
ucb1400_reg_write(ucb->ac97, UCB_IE_RIS, 0);
ucb1400_reg_write(ucb->ac97, UCB_IE_FAL, 0);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0xffff);
ucb1400_reg_write(ucb->ac97, UCB_IE_CLEAR, 0);
/* Read triggered interrupt. */
ucb->irq = probe_irq_off(mask);
if (ucb->irq < 0 || ucb->irq == NO_IRQ)
return -ENODEV;
return 0;
}