[PATCH 3/5] Staging/iio/adc/touchscreen/MXS: add i.MX23 support to the LRADC driver

Juergen Beisert
2013-09-04T13:01:44Z

Distinguish i.MX23 and i.MX28 at runtime and do the same for both SoC at least
for the 4 wire touchscreen.

Signed-off-by: Juergen Beisert <jbe@pengutronix.de>
CC: linux-arm-kernel at lists.infradead.org
CC: devel at driverdev.osuosl.org
CC: Marek Vasut <marex@denx.de>
CC: Fabio Estevam <fabio.estevam@freescale.com>
CC: Jonathan Cameron <jic23@cam.ac.uk>
---
drivers/staging/iio/adc/mxs-lradc.c | 134 +++++++++++++++++++++++++++---------
1 file changed, 102 insertions(+), 32 deletions(-)

diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
index 00e0c29..681ffd4 100644
--- a/drivers/staging/iio/adc/mxs-lradc.c
+++ b/drivers/staging/iio/adc/mxs-lradc.c
@@ -188,19 +188,33 @@ struct mxs_lradc {
# define LRADC_CTRL0_MX28_XNPSW /* XM */ (1 << 17)
# define LRADC_CTRL0_MX28_XPPSW /* XP */ (1 << 16)

+# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE (1 << 20)
+# define LRADC_CTRL0_MX23_YM (1 << 19)
+# define LRADC_CTRL0_MX23_XM (1 << 18)
+# define LRADC_CTRL0_MX23_YP (1 << 17)
+# define LRADC_CTRL0_MX23_XP (1 << 16)
+
#define LRADC_CTRL0_MX28_PLATE_MASK \
+ LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW

+#define LRADC_CTRL0_MX23_PLATE_MASK \
+ LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
+ LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
+ LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP
+
#define LRADC_CTRL1 0x10
#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN (1 << 24)
#define LRADC_CTRL1_LRADC_IRQ_EN(n) (1 << ((n) + 16))
#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK (0x1fff << 16)
+#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK (0x01ff << 16)
#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET 16
#define LRADC_CTRL1_TOUCH_DETECT_IRQ (1 << 8)
#define LRADC_CTRL1_LRADC_IRQ(n) (1 << (n))
#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK 0x1fff
+#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK 0x01ff
#define LRADC_CTRL1_LRADC_IRQ_OFFSET 0

#define LRADC_CTRL2 0x20
@@ -268,8 +282,9 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ 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);

/* Clean the slot's previous content, then set new one. */
@@ -323,10 +338,17 @@ 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);
+ if (lradc->soc == IMX28_LRADC) {
+ 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);
+ } else {
+ writel(LRADC_CTRL0_MX23_PLATE_MASK,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ writel(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+ }

msleep(LRADC_TS_SAMPLE_DELAY_MS);

@@ -371,22 +393,36 @@ 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;
+ if (lradc->soc == IMX28_LRADC)
+ ctrl0 = LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;
+ else
+ ctrl0 = LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM;
chan = 3;
break;
case LRADC_SAMPLE_Y:
- ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;
+ if (lradc->soc == IMX28_LRADC)
+ ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;
+ else
+ ctrl0 = LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM;
chan = 4;
break;
case LRADC_SAMPLE_PRESSURE:
- ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;
+ if (lradc->soc == IMX28_LRADC)
+ ctrl0 = LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;
+ else
+ ctrl0 = LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM;
chan = 5;
break;
}

if (change) {
- writel(LRADC_CTRL0_MX28_PLATE_MASK,
- lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL0_MX28_PLATE_MASK,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ else
+ writel(LRADC_CTRL0_MX23_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),
@@ -446,8 +482,12 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ else
+ writel(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);

if (likely(valid)) {
input_report_abs(lradc->ts_input, ABS_X, val_x);
@@ -495,8 +535,12 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+ else
+ writel(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);

/* Enable the touch-detect IRQ. */
writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
@@ -521,8 +565,12 @@ static void mxs_lradc_ts_close(struct input_dev *dev)
lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

/* Power-down touchscreen touch-detect circuitry. */
- writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
- lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+ else
+ writel(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
}

static int mxs_lradc_ts_register(struct mxs_lradc *lradc)
@@ -585,8 +633,13 @@ 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))
- return IRQ_NONE;
+ if (lradc->soc == IMX28_LRADC) {
+ if (!(reg & LRADC_CTRL1_MX28_LRADC_IRQ_MASK))
+ return IRQ_NONE;
+ } else {
+ if (!(reg & LRADC_CTRL1_MX23_LRADC_IRQ_MASK))
+ return IRQ_NONE;
+ }

/*
* Touchscreen IRQ handling code has priority and therefore
@@ -605,8 +658,12 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ writel(reg & LRADC_CTRL1_MX28_LRADC_IRQ_MASK,
+ lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+ else
+ writel(reg & LRADC_CTRL1_MX23_LRADC_IRQ_MASK,
+ lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

return IRQ_HANDLED;
}
@@ -726,8 +783,9 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ 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);

for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
@@ -767,8 +825,9 @@ static int mxs_lradc_buffer_postdisable(struct iio_dev *iio)
lradc->base + LRADC_DELAY(0) + STMP_OFFSET_REG_CLR);

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);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
+ lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

kfree(lradc->buffer);
mutex_unlock(&lradc->lock);
@@ -871,12 +930,13 @@ static int mxs_lradc_hw_init(struct mxs_lradc *lradc)
writel(0, lradc->base + LRADC_DELAY(3));

/* Configure the touchscreen type */
- writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
- lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
-
- if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE) {
+ if (lradc->soc == IMX28_LRADC) {
writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
- lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+
+ if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
+ writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
+ lradc->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
}

/* Start internal temperature sensing. */
@@ -889,8 +949,12 @@ 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);
+ if (lradc->soc == IMX28_LRADC)
+ writel(LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK,
+ lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+ else
+ writel(LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK,
+ lradc->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);

for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++)
writel(0, lradc->base + LRADC_DELAY(i));
@@ -950,6 +1014,12 @@ static int mxs_lradc_probe(struct platform_device *pdev)
dev_warn(dev, "Unsupported number of touchscreen wires (%d)\n",
ts_wires);

+ if ((lradc->soc == IMX23_LRADC) && (ts_wires == 5)) {
+ dev_warn(dev, "No support for 5 wire touches on i.MX23\n");
+ dev_warn(dev, "Falling back to 4 wire\n");
+ ts_wires = 4;
+ }
+
/* Grab all IRQ sources */
for (i = 0; i < of_cfg->irq_count; i++) {
lradc->irq[i] = platform_get_irq(pdev, i);
--
1.8.4.rc3