Commit f0b83cc8 authored by Juergen Beisert's avatar Juergen Beisert Committed by Jonathan Cameron
Browse files

Staging/iio/adc/touchscreen/MXS: simplify register access 



Replace the individual register access by a few shared access function to make the
code easier to read and in order to add the i.MX23 SoC in the next step.

Signed-off-by: default avatarJuergen Beisert <jbe@pengutronix.de>
Tested-by: default avatarMarek Vasut <marex@denx.de>
Acked-by: default avatarMarek Vasut <marex@denx.de>
Tested-by: default avatarLothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: default avatarJonathan 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>
parent 7e4d4a6f

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

+120 −84
Original line number Diff line number Diff line
@@ -238,6 +238,56 @@ struct mxs_lradc { 
#define LRADC_RESOLUTION			12

#define LRADC_SINGLE_SAMPLE_MASK		((1 << LRADC_RESOLUTION) - 1)



static void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)

{

	writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);

}



static void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val, u32 reg)

{

	writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);

}



static void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)

{

	writel(val, lradc->base + reg);

}



static u32 mxs_lradc_plate_mask(struct mxs_lradc *lradc)

{

	return LRADC_CTRL0_MX28_PLATE_MASK;

}



static u32 mxs_lradc_irq_en_mask(struct mxs_lradc *lradc)

{

	return LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK;

}



static u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)

{

	return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;

}



static u32 mxs_lradc_touch_detect_bit(struct mxs_lradc *lradc)

{

	return LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE;

}



static u32 mxs_lradc_drive_x_plate(struct mxs_lradc *lradc)

{

	return LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;

}



static u32 mxs_lradc_drive_y_plate(struct mxs_lradc *lradc)

{

	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;

}



static u32 mxs_lradc_drive_pressure(struct mxs_lradc *lradc)

{

	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;

}



/*

 * Raw I/O operations

 */
@@ -272,21 +322,19 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev, 
	 * Virtual channel 0 is always used here as the others are always not

	 * used if doing raw sampling.

	 */

	writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	writel(0xff, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

			LRADC_CTRL1);

	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);



	/* Clean the slot's previous content, then set new one. */

	writel(LRADC_CTRL4_LRADCSELECT_MASK(0),

		lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);

	writel(chan->channel, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0), LRADC_CTRL4);

	mxs_lradc_reg_set(lradc, chan->channel, LRADC_CTRL4);



	writel(0, lradc->base + LRADC_CH(0));

	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0));



	/* Enable the IRQ and start sampling the channel. */

	writel(LRADC_CTRL1_LRADC_IRQ_EN(0),

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);

	writel(1 << 0, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

	mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);

	mxs_lradc_reg_set(lradc, 1 << 0, LRADC_CTRL0);



	/* Wait for completion on the channel, 1 second max. */

	ret = wait_for_completion_killable_timeout(&lradc->completion, HZ);
@@ -300,8 +348,7 @@ static int mxs_lradc_read_raw(struct iio_dev *iio_dev, 
	ret = IIO_VAL_INT;



err:

	writel(LRADC_CTRL1_LRADC_IRQ_EN(0),

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);



	mutex_unlock(&lradc->lock);
@@ -327,10 +374,9 @@ static int mxs_lradc_ts_touched(struct mxs_lradc *lradc) 
	uint32_t reg;



	/* Enable touch detection. */

	writel(LRADC_CTRL0_MX28_PLATE_MASK,

		lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,

		lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

	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);
@@ -375,32 +421,33 @@ static int32_t mxs_lradc_ts_sample(struct mxs_lradc *lradc, 
	 */

	switch (plate) {

	case LRADC_SAMPLE_X:

		ctrl0 = LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;

		ctrl0 = mxs_lradc_drive_x_plate(lradc);

		chan = 3;

		break;

	case LRADC_SAMPLE_Y:

		ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;

		ctrl0 = mxs_lradc_drive_y_plate(lradc);

		chan = 4;

		break;

	case LRADC_SAMPLE_PRESSURE:

		ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;

		ctrl0 = mxs_lradc_drive_pressure(lradc);

		chan = 5;

		break;

	}



	if (change) {

		writel(LRADC_CTRL0_MX28_PLATE_MASK,

			lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

		writel(ctrl0, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);



		writel(LRADC_CTRL4_LRADCSELECT_MASK(slot),

			lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);

		writel(chan << LRADC_CTRL4_LRADCSELECT_OFFSET(slot),

			lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);

		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);

	}



	writel(0xffffffff, lradc->base + LRADC_CH(slot) + STMP_OFFSET_REG_CLR);

	writel(1 << slot, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

	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 {
@@ -410,8 +457,7 @@ static int32_t mxs_lradc_ts_sample(struct mxs_lradc *lradc, 
			break;

	} while (time_before(jiff, delay));



	writel(LRADC_CTRL1_LRADC_IRQ(slot),

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(slot), LRADC_CTRL1);



	if (time_after_eq(jiff, delay))

		return -ETIMEDOUT;
@@ -450,8 +496,8 @@ static void mxs_lradc_ts_work(struct work_struct *ts_work) 


	while (mxs_lradc_ts_touched(lradc)) {

		/* Disable touch detector so we can sample the touchscreen. */

		writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,

			lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

		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);
@@ -485,10 +531,8 @@ static void mxs_lradc_ts_work(struct work_struct *ts_work) 
		return;



	/* Restart the touchscreen interrupts. */

	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);

	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)
@@ -499,12 +543,11 @@ static int mxs_lradc_ts_open(struct input_dev *dev) 
	lradc->stop_touchscreen = false;



	/* Enable the touch-detect circuitry. */

	writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,

		lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

	mxs_lradc_reg_set(lradc, mxs_lradc_touch_detect_bit(lradc),

						LRADC_CTRL0);



	/* Enable the touch-detect IRQ. */

	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);

	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);



	return 0;

}
@@ -521,12 +564,11 @@ static void mxs_lradc_ts_close(struct input_dev *dev) 
	cancel_work_sync(&lradc->ts_work);



	/* Disable touchscreen touch-detect IRQ. */

	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,

						LRADC_CTRL1);



	/* Power-down touchscreen touch-detect circuitry. */

	writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,

		lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, mxs_lradc_touch_detect_bit(lradc), LRADC_CTRL0);

}



static int mxs_lradc_ts_register(struct mxs_lradc *lradc)
@@ -589,7 +631,7 @@ static irqreturn_t mxs_lradc_handle_irq(int irq, void *data) 
		LRADC_CTRL1_TOUCH_DETECT_IRQ_EN |

		LRADC_CTRL1_TOUCH_DETECT_IRQ;



	if (!(reg & LRADC_CTRL1_MX28_LRADC_IRQ_MASK))

	if (!(reg & mxs_lradc_irq_mask(lradc)))

		return IRQ_NONE;



	/*
@@ -598,8 +640,7 @@ static irqreturn_t mxs_lradc_handle_irq(int irq, void *data) 
	 * it ASAP

	 */

	if (reg & LRADC_CTRL1_TOUCH_DETECT_IRQ) {

		writel(ts_irq_mask,

			lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

		mxs_lradc_reg_clear(lradc, ts_irq_mask, LRADC_CTRL1);

		if (!lradc->stop_touchscreen)

			schedule_work(&lradc->ts_work);

	}
@@ -609,8 +650,7 @@ static irqreturn_t mxs_lradc_handle_irq(int irq, void *data) 
	else if (reg & LRADC_CTRL1_LRADC_IRQ(0))

		complete(&lradc->completion);



	writel(reg & LRADC_CTRL1_MX28_LRADC_IRQ_MASK,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, reg & mxs_lradc_irq_mask(lradc), LRADC_CTRL1);



	return IRQ_HANDLED;

}
@@ -629,7 +669,7 @@ static irqreturn_t mxs_lradc_trigger_handler(int irq, void *p) 


	for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {

		lradc->buffer[j] = readl(lradc->base + LRADC_CH(j));

		writel(chan_value, lradc->base + LRADC_CH(j));

		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(j));

		lradc->buffer[j] &= LRADC_CH_VALUE_MASK;

		lradc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;

		j++;
@@ -648,7 +688,7 @@ static int mxs_lradc_configure_trigger(struct iio_trigger *trig, bool state) 
	struct mxs_lradc *lradc = iio_priv(iio);

	const uint32_t st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;



	writel(LRADC_DELAY_KICK, lradc->base + LRADC_DELAY(0) + st);

	mxs_lradc_reg_wrt(lradc, LRADC_DELAY_KICK, LRADC_DELAY(0) + st);



	return 0;

}
@@ -724,29 +764,26 @@ static int mxs_lradc_buffer_preenable(struct iio_dev *iio) 
	if (ret < 0)

		goto err_buf;



	writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	writel(0xff, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

							LRADC_CTRL1);

	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);



	for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {

		ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);

		ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);

		ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);

		writel(chan_value, lradc->base + LRADC_CH(ofs));

		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(ofs));

		bitmap_set(&enable, ofs, 1);

		ofs++;

	}



	writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,

		lradc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);



	writel(ctrl4_clr, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);

	writel(ctrl4_set, lradc->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);



	writel(ctrl1_irq, lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);



	writel(enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,

		lradc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_SET);

	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |

					LRADC_DELAY_KICK, LRADC_DELAY(0));

	mxs_lradc_reg_clear(lradc, ctrl4_clr, LRADC_CTRL4);

	mxs_lradc_reg_set(lradc, ctrl4_set, LRADC_CTRL4);

	mxs_lradc_reg_set(lradc, ctrl1_irq, LRADC_CTRL1);

	mxs_lradc_reg_set(lradc, enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,

					LRADC_DELAY(0));



	return 0;
@@ -761,12 +798,12 @@ static int mxs_lradc_buffer_postdisable(struct iio_dev *iio) 
{

	struct mxs_lradc *lradc = iio_priv(iio);



	writel(LRADC_DELAY_TRIGGER_LRADCS_MASK | LRADC_DELAY_KICK,

		lradc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |

					LRADC_DELAY_KICK, LRADC_DELAY(0));



	writel(0xff, lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, 0xff, LRADC_CTRL0);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

					LRADC_CTRL1);



	kfree(lradc->buffer);

	mutex_unlock(&lradc->lock);
@@ -861,24 +898,24 @@ static int mxs_lradc_hw_init(struct mxs_lradc *lradc) 
		return ret;



	/* Configure DELAY CHANNEL 0 for generic ADC sampling. */

	writel(adc_cfg, lradc->base + LRADC_DELAY(0));

	mxs_lradc_reg_wrt(lradc, adc_cfg, LRADC_DELAY(0));



	/* Disable remaining DELAY CHANNELs */

	writel(0, lradc->base + LRADC_DELAY(1));

	writel(0, lradc->base + LRADC_DELAY(2));

	writel(0, lradc->base + LRADC_DELAY(3));

	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(1));

	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2));

	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3));



	/* Configure the touchscreen type */

	writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,

		lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,

							LRADC_CTRL0);



	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE) {

		writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,

			lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)

		mxs_lradc_reg_set(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,

				LRADC_CTRL0);

	}



	/* Start internal temperature sensing. */

	writel(0, lradc->base + LRADC_CTRL2);

	mxs_lradc_reg_wrt(lradc, 0, LRADC_CTRL2);



	return 0;

}
@@ -887,11 +924,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc *lradc) 
{

	int i;



	writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,

		lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

	mxs_lradc_reg_clear(lradc, mxs_lradc_irq_en_mask(lradc), LRADC_CTRL1);



	for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++)

		writel(0, lradc->base + LRADC_DELAY(i));

		mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i));

}



static const struct of_device_id mxs_lradc_dt_ids[] = {

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