Staging/iio/adc/touchscreen/MXS: remove old touchscreen detection implementation

Signed-off-by: Juergen Beisert <jbe@pengutronix.de>
Tested-by: Marek Vasut <marex@denx.de>
Acked-by: Marek Vasut <marex@denx.de>
Tested-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

CC: linux-arm-kernel@lists.infradead.org
CC: linux-input@vger.kernel.org
CC: devel@driverdev.osuosl.org
CC: Marek Vasut <marex@denx.de>
CC: Fabio Estevam <fabio.estevam@freescale.com>

drivers/staging/iio/adc/mxs-lradc.c

@@ -186,7 +186,6 @@ struct mxs_lradc {
 	bool			use_touchbutton;
 
 	struct input_dev	*ts_input;
-	struct work_struct	ts_work;
 
 	enum mxs_lradc_id	soc;
 	enum lradc_ts_plate	cur_plate; /* statemachine */
@@ -830,168 +829,6 @@ static const struct iio_info mxs_lradc_iio_info = {
 	.read_raw		= mxs_lradc_read_raw,
 };
 
-static int mxs_lradc_ts_touched(struct mxs_lradc *lradc)
-{
-	uint32_t reg;
-
-	/* Enable touch detection. */
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-	mxs_lradc_reg_set(lradc, mxs_lradc_touch_detect_bit(lradc),
-								LRADC_CTRL0);
-
-	msleep(LRADC_TS_SAMPLE_DELAY_MS);
-
-	reg = readl(lradc->base + LRADC_STATUS);
-
-	return reg & LRADC_STATUS_TOUCH_DETECT_RAW;
-}
-
-static int32_t mxs_lradc_ts_sample(struct mxs_lradc *lradc,
-				enum lradc_ts_plate plate, int change)
-{
-	unsigned long delay, jiff;
-	uint32_t reg, ctrl0 = 0, chan = 0;
-	/* The touchscreen always uses CTRL4 slot #7. */
-	const uint8_t slot = 7;
-	uint32_t val;
-
-	/*
-	 * There are three correct configurations of the controller sampling
-	 * the touchscreen, each of these configuration provides different
-	 * information from the touchscreen.
-	 *
-	 * The following table describes the sampling configurations:
-	 * +-------------+-------+-------+-------+
-	 * | Wire \ Axis |   X   |   Y   |   Z   |
-	 * +---------------------+-------+-------+
-	 * |   X+ (CH2)  |   HI  |   TS  |   TS  |
-	 * +-------------+-------+-------+-------+
-	 * |   X- (CH4)  |   LO  |   SH  |   HI  |
-	 * +-------------+-------+-------+-------+
-	 * |   Y+ (CH3)  |   SH  |   HI  |   HI  |
-	 * +-------------+-------+-------+-------+
-	 * |   Y- (CH5)  |   TS  |   LO  |   SH  |
-	 * +-------------+-------+-------+-------+
-	 *
-	 * HI ... strong '1'  ; LO ... strong '0'
-	 * SH ... sample here ; TS ... tri-state
-	 *
-	 * There are a few other ways of obtaining the Z coordinate
-	 * (aka. pressure), but the one in the table seems to be the
-	 * most reliable one.
-	 */
-	switch (plate) {
-	case LRADC_SAMPLE_X:
-		ctrl0 = mxs_lradc_drive_x_plate(lradc);
-		chan = 3;
-		break;
-	case LRADC_SAMPLE_Y:
-		ctrl0 = mxs_lradc_drive_y_plate(lradc);
-		chan = 4;
-		break;
-	case LRADC_SAMPLE_PRESSURE:
-		ctrl0 = mxs_lradc_drive_pressure(lradc);
-		chan = 5;
-		break;
-	}
-
-	if (change) {
-		mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc),
-						LRADC_CTRL0);
-		mxs_lradc_reg_set(lradc, ctrl0, LRADC_CTRL0);
-
-		mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(slot),
-						LRADC_CTRL4);
-		mxs_lradc_reg_set(lradc,
-				chan << LRADC_CTRL4_LRADCSELECT_OFFSET(slot),
-				LRADC_CTRL4);
-	}
-
-	mxs_lradc_reg_clear(lradc, 0xffffffff, LRADC_CH(slot));
-	mxs_lradc_reg_set(lradc, 1 << slot, LRADC_CTRL0);
-
-	delay = jiffies + msecs_to_jiffies(LRADC_TS_SAMPLE_DELAY_MS);
-	do {
-		jiff = jiffies;
-		reg = readl_relaxed(lradc->base + LRADC_CTRL1);
-		if (reg & LRADC_CTRL1_LRADC_IRQ(slot))
-			break;
-	} while (time_before(jiff, delay));
-
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(slot), LRADC_CTRL1);
-
-	if (time_after_eq(jiff, delay))
-		return -ETIMEDOUT;
-
-	val = readl(lradc->base + LRADC_CH(slot));
-	val &= LRADC_CH_VALUE_MASK;
-
-	return val;
-}
-
-static int32_t mxs_lradc_ts_sample_filter(struct mxs_lradc *lradc,
-				enum lradc_ts_plate plate)
-{
-	int32_t val, tot = 0;
-	int i;
-
-	val = mxs_lradc_ts_sample(lradc, plate, 1);
-
-	/* Delay a bit so the touchscreen is stable. */
-	mdelay(2);
-
-	for (i = 0; i < LRADC_TS_SAMPLE_AMOUNT; i++) {
-		val = mxs_lradc_ts_sample(lradc, plate, 0);
-		tot += val;
-	}
-
-	return tot / LRADC_TS_SAMPLE_AMOUNT;
-}
-
-static void mxs_lradc_ts_work(struct work_struct *ts_work)
-{
-	struct mxs_lradc *lradc = container_of(ts_work,
-				struct mxs_lradc, ts_work);
-	int val_x, val_y, val_p;
-	bool valid = false;
-
-	while (mxs_lradc_ts_touched(lradc)) {
-		/* Disable touch detector so we can sample the touchscreen. */
-		mxs_lradc_reg_clear(lradc, mxs_lradc_touch_detect_bit(lradc),
-						LRADC_CTRL0);
-
-		if (likely(valid)) {
-			input_report_abs(lradc->ts_input, ABS_X, val_x);
-			input_report_abs(lradc->ts_input, ABS_Y, val_y);
-			input_report_abs(lradc->ts_input, ABS_PRESSURE, val_p);
-			input_report_key(lradc->ts_input, BTN_TOUCH, 1);
-			input_sync(lradc->ts_input);
-		}
-
-		valid = false;
-
-		val_x = mxs_lradc_ts_sample_filter(lradc, LRADC_SAMPLE_X);
-		if (val_x < 0)
-			continue;
-		val_y = mxs_lradc_ts_sample_filter(lradc, LRADC_SAMPLE_Y);
-		if (val_y < 0)
-			continue;
-		val_p = mxs_lradc_ts_sample_filter(lradc, LRADC_SAMPLE_PRESSURE);
-		if (val_p < 0)
-			continue;
-
-		valid = true;
-	}
-
-	input_report_abs(lradc->ts_input, ABS_PRESSURE, 0);
-	input_report_key(lradc->ts_input, BTN_TOUCH, 0);
-	input_sync(lradc->ts_input);
-
-	/* Restart the touchscreen interrupts. */
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ, LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
-}
-
 static int mxs_lradc_ts_open(struct input_dev *dev)
 {
 	struct mxs_lradc *lradc = input_get_drvdata(dev);