*/
#include <linux/module.h>
-#include <linux/hrtimer.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/i2c/tsc2007.h>
-#define TS_POLL_DELAY (10 * 1000) /* ns delay before the first sample */
-#define TS_POLL_PERIOD (5 * 1000) /* ns delay between samples */
+#define TS_POLL_DELAY 1 /* ms delay between samples */
+#define TS_POLL_PERIOD 1 /* ms delay between samples */
#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
#define TSC2007_MEASURE_AUX (0x2 << 4)
struct tsc2007 {
struct input_dev *input;
char phys[32];
- struct hrtimer timer;
- struct ts_event tc;
+ struct delayed_work work;
struct i2c_client *client;
- spinlock_t lock;
-
u16 model;
u16 x_plate_ohms;
- unsigned pendown;
+ bool pendown;
int irq;
int (*get_pendown_state)(void);
return val;
}
-static void tsc2007_send_event(void *tsc)
+static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
{
- struct tsc2007 *ts = tsc;
- u32 rt;
- u16 x, y, z1, z2;
+ /* y- still on; turn on only y+ (and ADC) */
+ tc->y = tsc2007_xfer(tsc, READ_Y);
+
+ /* turn y- off, x+ on, then leave in lowpower */
+ tc->x = tsc2007_xfer(tsc, READ_X);
+
+ /* turn y+ off, x- on; we'll use formula #1 */
+ tc->z1 = tsc2007_xfer(tsc, READ_Z1);
+ tc->z2 = tsc2007_xfer(tsc, READ_Z2);
- x = ts->tc.x;
- y = ts->tc.y;
- z1 = ts->tc.z1;
- z2 = ts->tc.z2;
+ /* Prepare for next touch reading - power down ADC, enable PENIRQ */
+ tsc2007_xfer(tsc, PWRDOWN);
+}
+
+static u32 tsc2007_calculate_pressure(struct tsc2007 *tsc, struct ts_event *tc)
+{
+ u32 rt = 0;
/* range filtering */
- if (x == MAX_12BIT)
- x = 0;
+ if (tc->x == MAX_12BIT)
+ tc->x = 0;
- if (likely(x && z1)) {
+ if (likely(tc->x && tc->z1)) {
/* compute touch pressure resistance using equation #1 */
- rt = z2;
- rt -= z1;
- rt *= x;
- rt *= ts->x_plate_ohms;
- rt /= z1;
+ rt = tc->z2 - tc->z1;
+ rt *= tc->x;
+ rt *= tsc->x_plate_ohms;
+ rt /= tc->z1;
rt = (rt + 2047) >> 12;
- } else
- rt = 0;
+ }
+
+ return rt;
+}
+
+static void tsc2007_send_up_event(struct tsc2007 *tsc)
+{
+ struct input_dev *input = tsc->input;
- /* Sample found inconsistent by debouncing or pressure is beyond
- * the maximum. Don't report it to user space, repeat at least
- * once more the measurement
+ dev_dbg(&tsc->client->dev, "UP\n");
+
+ input_report_key(input, BTN_TOUCH, 0);
+ input_report_abs(input, ABS_PRESSURE, 0);
+ input_sync(input);
+}
+
+static void tsc2007_work(struct work_struct *work)
+{
+ struct tsc2007 *ts =
+ container_of(to_delayed_work(work), struct tsc2007, work);
+ struct ts_event tc;
+ u32 rt;
+
+ /*
+ * NOTE: We can't rely on the pressure to determine the pen down
+ * state, even though this controller has a pressure sensor.
+ * The pressure value can fluctuate for quite a while after
+ * lifting the pen and in some cases may not even settle at the
+ * expected value.
+ *
+ * The only safe way to check for the pen up condition is in the
+ * work function by reading the pen signal state (it's a GPIO
+ * and IRQ). Unfortunately such callback is not always available,
+ * in that case we have rely on the pressure anyway.
*/
+ if (ts->get_pendown_state) {
+ if (unlikely(!ts->get_pendown_state())) {
+ tsc2007_send_up_event(ts);
+ ts->pendown = false;
+ goto out;
+ }
+
+ dev_dbg(&ts->client->dev, "pen is still down\n");
+ }
+
+ tsc2007_read_values(ts, &tc);
+
+ rt = tsc2007_calculate_pressure(ts, &tc);
if (rt > MAX_12BIT) {
+ /*
+ * Sample found inconsistent by debouncing or pressure is
+ * beyond the maximum. Don't report it to user space,
+ * repeat at least once more the measurement.
+ */
dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt);
+ goto out;
- hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
- HRTIMER_MODE_REL);
- return;
}
- /* NOTE: We can't rely on the pressure to determine the pen down
- * state, even this controller has a pressure sensor. The pressure
- * value can fluctuate for quite a while after lifting the pen and
- * in some cases may not even settle at the expected value.
- *
- * The only safe way to check for the pen up condition is in the
- * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
- */
if (rt) {
struct input_dev *input = ts->input;
dev_dbg(&ts->client->dev, "DOWN\n");
input_report_key(input, BTN_TOUCH, 1);
- ts->pendown = 1;
+ ts->pendown = true;
}
- input_report_abs(input, ABS_X, x);
- input_report_abs(input, ABS_Y, y);
+ input_report_abs(input, ABS_X, tc.x);
+ input_report_abs(input, ABS_Y, tc.y);
input_report_abs(input, ABS_PRESSURE, rt);
input_sync(input);
dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n",
- x, y, rt);
+ tc.x, tc.y, rt);
+
+ } else if (!ts->get_pendown_state && ts->pendown) {
+ /*
+ * We don't have callback to check pendown state, so we
+ * have to assume that since pressure reported is 0 the
+ * pen was lifted up.
+ */
+ tsc2007_send_up_event(ts);
+ ts->pendown = false;
}
- hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
- HRTIMER_MODE_REL);
-}
-
-static int tsc2007_read_values(struct tsc2007 *tsc)
-{
- /* y- still on; turn on only y+ (and ADC) */
- tsc->tc.y = tsc2007_xfer(tsc, READ_Y);
-
- /* turn y- off, x+ on, then leave in lowpower */
- tsc->tc.x = tsc2007_xfer(tsc, READ_X);
-
- /* turn y+ off, x- on; we'll use formula #1 */
- tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1);
- tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2);
-
- /* power down */
- tsc2007_xfer(tsc, PWRDOWN);
-
- return 0;
-}
-
-static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle)
-{
- struct tsc2007 *ts = container_of(handle, struct tsc2007, timer);
-
- spin_lock_irq(&ts->lock);
-
- if (unlikely(!ts->get_pendown_state() && ts->pendown)) {
- struct input_dev *input = ts->input;
-
- dev_dbg(&ts->client->dev, "UP\n");
-
- input_report_key(input, BTN_TOUCH, 0);
- input_report_abs(input, ABS_PRESSURE, 0);
- input_sync(input);
-
- ts->pendown = 0;
+ out:
+ if (ts->pendown)
+ schedule_delayed_work(&ts->work,
+ msecs_to_jiffies(TS_POLL_PERIOD));
+ else
enable_irq(ts->irq);
- } else {
- /* pen is still down, continue with the measurement */
- dev_dbg(&ts->client->dev, "pen is still down\n");
-
- tsc2007_read_values(ts);
- tsc2007_send_event(ts);
- }
-
- spin_unlock_irq(&ts->lock);
-
- return HRTIMER_NORESTART;
}
static irqreturn_t tsc2007_irq(int irq, void *handle)
{
struct tsc2007 *ts = handle;
- unsigned long flags;
-
- spin_lock_irqsave(&ts->lock, flags);
- if (likely(ts->get_pendown_state())) {
+ if (!ts->get_pendown_state || likely(ts->get_pendown_state())) {
disable_irq_nosync(ts->irq);
- hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
- HRTIMER_MODE_REL);
+ schedule_delayed_work(&ts->work,
+ msecs_to_jiffies(TS_POLL_DELAY));
}
if (ts->clear_penirq)
ts->clear_penirq();
- spin_unlock_irqrestore(&ts->lock, flags);
-
return IRQ_HANDLED;
}
-static int tsc2007_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static void tsc2007_free_irq(struct tsc2007 *ts)
+{
+ free_irq(ts->irq, ts);
+ if (cancel_delayed_work_sync(&ts->work)) {
+ /*
+ * Work was pending, therefore we need to enable
+ * IRQ here to balance the disable_irq() done in the
+ * interrupt handler.
+ */
+ enable_irq(ts->irq);
+ }
+}
+
+static int __devinit tsc2007_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
{
struct tsc2007 *ts;
struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data;
}
ts->client = client;
- i2c_set_clientdata(client, ts);
-
+ ts->irq = client->irq;
ts->input = input_dev;
-
- hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- ts->timer.function = tsc2007_timer;
-
- spin_lock_init(&ts->lock);
+ INIT_DELAYED_WORK(&ts->work, tsc2007_work);
ts->model = pdata->model;
ts->x_plate_ohms = pdata->x_plate_ohms;
ts->get_pendown_state = pdata->get_pendown_state;
ts->clear_penirq = pdata->clear_penirq;
- pdata->init_platform_hw();
-
snprintf(ts->phys, sizeof(ts->phys),
"%s/input0", dev_name(&client->dev));
input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
- tsc2007_read_values(ts);
-
- ts->irq = client->irq;
+ if (pdata->init_platform_hw)
+ pdata->init_platform_hw();
err = request_irq(ts->irq, tsc2007_irq, 0,
client->dev.driver->name, ts);
goto err_free_mem;
}
+ /* Prepare for touch readings - power down ADC and enable PENIRQ */
+ err = tsc2007_xfer(ts, PWRDOWN);
+ if (err < 0)
+ goto err_free_irq;
+
err = input_register_device(input_dev);
if (err)
goto err_free_irq;
- dev_info(&client->dev, "registered with irq (%d)\n", ts->irq);
+ i2c_set_clientdata(client, ts);
return 0;
err_free_irq:
- free_irq(ts->irq, ts);
- hrtimer_cancel(&ts->timer);
+ tsc2007_free_irq(ts);
+ if (pdata->exit_platform_hw)
+ pdata->exit_platform_hw();
err_free_mem:
input_free_device(input_dev);
kfree(ts);
return err;
}
-static int tsc2007_remove(struct i2c_client *client)
+static int __devexit tsc2007_remove(struct i2c_client *client)
{
struct tsc2007 *ts = i2c_get_clientdata(client);
- struct tsc2007_platform_data *pdata;
+ struct tsc2007_platform_data *pdata = client->dev.platform_data;
- pdata = client->dev.platform_data;
- pdata->exit_platform_hw();
+ tsc2007_free_irq(ts);
+
+ if (pdata->exit_platform_hw)
+ pdata->exit_platform_hw();
- free_irq(ts->irq, ts);
- hrtimer_cancel(&ts->timer);
input_unregister_device(ts->input);
kfree(ts);
},
.id_table = tsc2007_idtable,
.probe = tsc2007_probe,
- .remove = tsc2007_remove,
+ .remove = __devexit_p(tsc2007_remove),
};
static int __init tsc2007_init(void)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff