in touchscreen/ads7846.c [1212:1412]
static int ads7846_probe(struct spi_device *spi)
{
const struct ads7846_platform_data *pdata;
struct ads7846 *ts;
struct device *dev = &spi->dev;
struct ads7846_packet *packet;
struct input_dev *input_dev;
unsigned long irq_flags;
int err;
if (!spi->irq) {
dev_dbg(dev, "no IRQ?\n");
return -EINVAL;
}
/* don't exceed max specified sample rate */
if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
dev_err(dev, "f(sample) %d KHz?\n",
(spi->max_speed_hz/SAMPLE_BITS)/1000);
return -EINVAL;
}
/*
* We'd set TX word size 8 bits and RX word size to 13 bits ... except
* that even if the hardware can do that, the SPI controller driver
* may not. So we stick to very-portable 8 bit words, both RX and TX.
*/
spi->bits_per_word = 8;
spi->mode &= ~SPI_MODE_X_MASK;
spi->mode |= SPI_MODE_0;
err = spi_setup(spi);
if (err < 0)
return err;
ts = devm_kzalloc(dev, sizeof(struct ads7846), GFP_KERNEL);
if (!ts)
return -ENOMEM;
packet = devm_kzalloc(dev, sizeof(struct ads7846_packet), GFP_KERNEL);
if (!packet)
return -ENOMEM;
input_dev = devm_input_allocate_device(dev);
if (!input_dev)
return -ENOMEM;
spi_set_drvdata(spi, ts);
ts->packet = packet;
ts->spi = spi;
ts->input = input_dev;
mutex_init(&ts->lock);
init_waitqueue_head(&ts->wait);
pdata = dev_get_platdata(dev);
if (!pdata) {
pdata = ads7846_probe_dt(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
}
ts->model = pdata->model ? : 7846;
ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
ts->vref_mv = pdata->vref_mv;
if (pdata->debounce_max) {
ts->debounce_max = pdata->debounce_max;
if (ts->debounce_max < 2)
ts->debounce_max = 2;
ts->debounce_tol = pdata->debounce_tol;
ts->debounce_rep = pdata->debounce_rep;
ts->filter = ads7846_debounce_filter;
ts->filter_data = ts;
} else {
ts->filter = ads7846_no_filter;
}
err = ads7846_setup_pendown(spi, ts, pdata);
if (err)
return err;
if (pdata->penirq_recheck_delay_usecs)
ts->penirq_recheck_delay_usecs =
pdata->penirq_recheck_delay_usecs;
ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);
input_dev->name = ts->name;
input_dev->phys = ts->phys;
input_dev->id.bustype = BUS_SPI;
input_dev->id.product = pdata->model;
input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
input_set_abs_params(input_dev, ABS_X,
pdata->x_min ? : 0,
pdata->x_max ? : MAX_12BIT,
0, 0);
input_set_abs_params(input_dev, ABS_Y,
pdata->y_min ? : 0,
pdata->y_max ? : MAX_12BIT,
0, 0);
input_set_abs_params(input_dev, ABS_PRESSURE,
pdata->pressure_min, pdata->pressure_max, 0, 0);
/*
* Parse common framework properties. Must be done here to ensure the
* correct behaviour in case of using the legacy vendor bindings. The
* general binding value overrides the vendor specific one.
*/
touchscreen_parse_properties(ts->input, false, &ts->core_prop);
ts->pressure_max = input_abs_get_max(input_dev, ABS_PRESSURE) ? : ~0;
/*
* Check if legacy ti,swap-xy binding is used instead of
* touchscreen-swapped-x-y
*/
if (!ts->core_prop.swap_x_y && pdata->swap_xy) {
swap(input_dev->absinfo[ABS_X], input_dev->absinfo[ABS_Y]);
ts->core_prop.swap_x_y = true;
}
ads7846_setup_spi_msg(ts, pdata);
ts->reg = devm_regulator_get(dev, "vcc");
if (IS_ERR(ts->reg)) {
err = PTR_ERR(ts->reg);
dev_err(dev, "unable to get regulator: %d\n", err);
return err;
}
err = regulator_enable(ts->reg);
if (err) {
dev_err(dev, "unable to enable regulator: %d\n", err);
return err;
}
err = devm_add_action_or_reset(dev, ads7846_regulator_disable, ts->reg);
if (err)
return err;
irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING;
irq_flags |= IRQF_ONESHOT;
err = devm_request_threaded_irq(dev, spi->irq,
ads7846_hard_irq, ads7846_irq,
irq_flags, dev->driver->name, ts);
if (err && err != -EPROBE_DEFER && !pdata->irq_flags) {
dev_info(dev,
"trying pin change workaround on irq %d\n", spi->irq);
irq_flags |= IRQF_TRIGGER_RISING;
err = devm_request_threaded_irq(dev, spi->irq,
ads7846_hard_irq, ads7846_irq,
irq_flags, dev->driver->name,
ts);
}
if (err) {
dev_dbg(dev, "irq %d busy?\n", spi->irq);
return err;
}
err = ads784x_hwmon_register(spi, ts);
if (err)
return err;
dev_info(dev, "touchscreen, irq %d\n", spi->irq);
/*
* Take a first sample, leaving nPENIRQ active and vREF off; avoid
* the touchscreen, in case it's not connected.
*/
if (ts->model == 7845)
ads7845_read12_ser(dev, PWRDOWN);
else
(void) ads7846_read12_ser(dev, READ_12BIT_SER(vaux));
err = devm_device_add_group(dev, &ads784x_attr_group);
if (err)
return err;
err = input_register_device(input_dev);
if (err)
return err;
device_init_wakeup(dev, pdata->wakeup);
/*
* If device does not carry platform data we must have allocated it
* when parsing DT data.
*/
if (!dev_get_platdata(dev))
devm_kfree(dev, (void *)pdata);
return 0;
}