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Groups > linux.kernel > #1602231 > unrolled thread

[PATCH v15 0/5] mxs-lradc: Split driver into MFD

Started byKsenija Stanojevic <ksenija.stanojevic@gmail.com>
First post2017-03-16 13:30 +0100
Last post2017-03-23 13:40 +0100
Articles 6 — 4 participants

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Contents

  [PATCH v15 0/5] mxs-lradc: Split driver into MFD Ksenija Stanojevic <ksenija.stanojevic@gmail.com> - 2017-03-16 13:30 +0100
    [PATCH v15 3/5] input: touchscreen: mxs-lradc: Add support for touchscreen Ksenija Stanojevic <ksenija.stanojevic@gmail.com> - 2017-03-16 13:30 +0100
    Re: [PATCH v15 0/5] mxs-lradc: Split driver into MFD Stefan Wahren <stefan.wahren@i2se.com> - 2017-03-17 08:10 +0100
    Re: [PATCH v15 0/5] mxs-lradc: Split driver into MFD Jonathan Cameron <jic23@kernel.org> - 2017-03-19 12:20 +0100
      Re: [PATCH v15 0/5] mxs-lradc: Split driver into MFD Lee Jones <lee.jones@linaro.org> - 2017-03-20 12:40 +0100
    [GIT PULL] Immutable branch between MFD, IIO and Input due for the  v4.12 merge window Lee Jones <lee.jones@linaro.org> - 2017-03-23 13:40 +0100

#1602231 — [PATCH v15 0/5] mxs-lradc: Split driver into MFD

FromKsenija Stanojevic <ksenija.stanojevic@gmail.com>
Date2017-03-16 13:30 +0100
Subject[PATCH v15 0/5] mxs-lradc: Split driver into MFD
Message-ID<tlCHv-6I6-7@gated-at.bofh.it>
Split existing driver mxs-lradc into MFD with touchscreen and
IIO part.

Tested on I.MX28

Ksenija Stanojevic (5):
  mfd: mxs-lradc: Add support for mxs-lradc MFD
  iio: adc: mxs-lradc: Add support for adc driver
  input: touchscreen: mxs-lradc: Add support for touchscreen
  iio: adc: mxs-lradc: Remove driver
  mfd: Move binding document

 .../bindings/{iio/adc => mfd}/mxs-lradc.txt        |    0
 drivers/iio/adc/Kconfig                            |   27 +-
 drivers/iio/adc/Makefile                           |    2 +-
 drivers/iio/adc/mxs-lradc-adc.c                    |  843 ++++++++++
 drivers/iio/adc/mxs-lradc.c                        | 1750 --------------------
 drivers/input/touchscreen/Kconfig                  |   10 +
 drivers/input/touchscreen/Makefile                 |    1 +
 drivers/input/touchscreen/mxs-lradc-ts.c           |  714 ++++++++
 drivers/mfd/Kconfig                                |   17 +
 drivers/mfd/Makefile                               |    1 +
 drivers/mfd/mxs-lradc.c                            |  267 +++
 include/linux/mfd/mxs-lradc.h                      |  187 +++
 12 files changed, 2054 insertions(+), 1765 deletions(-)
 rename Documentation/devicetree/bindings/{iio/adc => mfd}/mxs-lradc.txt (100%)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
 delete mode 100644 drivers/iio/adc/mxs-lradc.c
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

-- 
1.9.1

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#1602233 — [PATCH v15 3/5] input: touchscreen: mxs-lradc: Add support for touchscreen

FromKsenija Stanojevic <ksenija.stanojevic@gmail.com>
Date2017-03-16 13:30 +0100
Subject[PATCH v15 3/5] input: touchscreen: mxs-lradc: Add support for touchscreen
Message-ID<tlCHx-6I6-39@gated-at.bofh.it>
In reply to#1602231
Add 4-wire/5-wire touchscreen controller.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
---
Changes in v15:
 - use input_set_capability(input, EV_KEY, BTN_TOUCH) instead of __set_bit()s
 - use return mxs_lradc_ts_register(ts) instead of return 0.

Changes in v14:
 - none

Changes in v13:
 - use struct state_info instead of using functions for doing
   conditionals on every operation.
 - call mxs_lradc_ts_stop() before requesting interrupts.

Changes in v12:
 - none

Changes in v11:
 - use dev_get_drvdata instead dev_get_platdata
 - use writel instead mxs_lradc_reg_* functions

Changes in v10:
 - none

Changes in v9:
 - none

Changes in v8:
 - rebase onto 4.9-rc1

Changes in v7:
 - remove touch_ret variable in probe and use ret instead
 - make error check on of_property_read_u32 in probe

Changes in v6:
 - update copyright

Changes in v5:
 - add field void __iomem *base to struct mxs_lradc_adc
 - change arguments in all functions for accessing I/O memory
   to follow the previous change.
 - use devm_ioremap for mapping I/O memory

Changes in v4:
 - update copyright
 - use platform_get_irq_byname
 - use irq_of_parse_and_map

Changes in v3:
 - make buffer large enough for timestamps
 - remove unnecessary blank lines

Changes in v2:
 - improve commit message
 - do not change spacing in Kconfig
 - impove formating
 - remove wrapper show_scale_avail
 - use correct syntax for comments
 - use devm_iio_trigger_alloc
 - do not allocate buffer dynamically
 - use iio_device_claim_*_mode helpers
 - add spinlock in struct mxs_lradc_ts to enable locking in interrupt handler
 - only grab irqs that are relevant to adc
 - remove blank line at the end of the file
 - change licence to GPL
 - add copyright

 drivers/input/touchscreen/Kconfig        |  10 +
 drivers/input/touchscreen/Makefile       |   1 +
 drivers/input/touchscreen/mxs-lradc-ts.c | 714 +++++++++++++++++++++++++++++++
 3 files changed, 725 insertions(+)
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 0335997..52458cf 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -829,6 +829,16 @@ config TOUCHSCREEN_USB_COMPOSITE
 	  To compile this driver as a module, choose M here: the
 	  module will be called usbtouchscreen.
 
+config TOUCHSCREEN_MXS_LRADC
+	tristate "Freescale i.MX23/i.MX28 LRADC touchscreen"
+	depends on MFD_MXS_LRADC
+	help
+	  Say Y here if you have a touchscreen connected to the low-resolution
+	  analog-to-digital converter (LRADC) on an i.MX23 or i.MX28 processor.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called mxs-lradc-ts.
+
 config TOUCHSCREEN_MX25
 	tristate "Freescale i.MX25 touchscreen input driver"
 	depends on MFD_MX25_TSADC
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index b622e53..96761ce 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_TOUCHSCREEN_INEXIO)	+= inexio.o
 obj-$(CONFIG_TOUCHSCREEN_IPROC)		+= bcm_iproc_tsc.o
 obj-$(CONFIG_TOUCHSCREEN_LPC32XX)	+= lpc32xx_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MAX11801)	+= max11801_ts.o
+obj-$(CONFIG_TOUCHSCREEN_MXS_LRADC)     += mxs-lradc-ts.o
 obj-$(CONFIG_TOUCHSCREEN_MX25)		+= fsl-imx25-tcq.o
 obj-$(CONFIG_TOUCHSCREEN_MC13783)	+= mc13783_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MCS5000)	+= mcs5000_ts.o
diff --git a/drivers/input/touchscreen/mxs-lradc-ts.c b/drivers/input/touchscreen/mxs-lradc-ts.c
new file mode 100644
index 0000000..4b4aebf
--- /dev/null
+++ b/drivers/input/touchscreen/mxs-lradc-ts.c
@@ -0,0 +1,714 @@
+/*
+ * Freescale MXS LRADC touchscreen driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
+ *
+ * Authors:
+ *  Marek Vasut <marex@denx.de>
+ *  Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+
+const char *mxs_lradc_ts_irq_names[] = {
+	"mxs-lradc-touchscreen",
+	"mxs-lradc-channel6",
+	"mxs-lradc-channel7",
+};
+
+/*
+ * Touchscreen handling
+ */
+enum mxs_lradc_ts_plate {
+	LRADC_TOUCH = 0,
+	LRADC_SAMPLE_X,
+	LRADC_SAMPLE_Y,
+	LRADC_SAMPLE_PRESSURE,
+	LRADC_SAMPLE_VALID,
+};
+
+struct mxs_lradc_ts {
+	struct mxs_lradc	*lradc;
+	struct device		*dev;
+
+	void __iomem		*base;
+	/*
+	 * When the touchscreen is enabled, we give it two private virtual
+	 * channels: #6 and #7. This means that only 6 virtual channels (instead
+	 * of 8) will be available for buffered capture.
+	 */
+#define TOUCHSCREEN_VCHANNEL1		7
+#define TOUCHSCREEN_VCHANNEL2		6
+
+	struct input_dev	*ts_input;
+
+	enum mxs_lradc_ts_plate	cur_plate; /* state machine */
+	bool			ts_valid;
+	unsigned int		ts_x_pos;
+	unsigned int		ts_y_pos;
+	unsigned int		ts_pressure;
+
+	/* handle touchscreen's physical behaviour */
+	/* samples per coordinate */
+	unsigned int		over_sample_cnt;
+	/* time clocks between samples */
+	unsigned int		over_sample_delay;
+	/* time in clocks to wait after the plates where switched */
+	unsigned int		settling_delay;
+	spinlock_t		lock;
+};
+
+struct state_info {
+	u32		mask;
+	u32		bit;
+	u32		x_plate;
+	u32		y_plate;
+	u32		pressure;
+};
+
+static struct state_info info[] = {
+	{LRADC_CTRL0_MX23_PLATE_MASK, LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
+	 LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM,
+	 LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM,
+	 LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM},
+	{LRADC_CTRL0_MX28_PLATE_MASK, LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
+	 LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW,
+	 LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW,
+	 LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW}
+};
+
+static bool mxs_lradc_check_touch_event(struct mxs_lradc_ts *ts)
+{
+	return !!(readl(ts->base + LRADC_STATUS) &
+					LRADC_STATUS_TOUCH_DETECT_RAW);
+}
+
+static void mxs_lradc_map_ts_channel(struct mxs_lradc_ts *ts, unsigned int vch,
+				     unsigned int ch)
+{
+	writel(LRADC_CTRL4_LRADCSELECT_MASK(vch),
+	       ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
+	writel(LRADC_CTRL4_LRADCSELECT(vch, ch),
+	       ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
+}
+
+static void mxs_lradc_setup_ts_channel(struct mxs_lradc_ts *ts, unsigned int ch)
+{
+	/*
+	 * prepare for oversampling conversion
+	 *
+	 * from the datasheet:
+	 * "The ACCUMULATE bit in the appropriate channel register
+	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
+	 * otherwise, the IRQs will not fire."
+	 */
+	writel(LRADC_CH_ACCUMULATE |
+	       LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1),
+	       ts->base + LRADC_CH(ch));
+
+	/* from the datasheet:
+	 * "Software must clear this register in preparation for a
+	 * multi-cycle accumulation.
+	 */
+	writel(LRADC_CH_VALUE_MASK,
+	       ts->base + LRADC_CH(ch) + STMP_OFFSET_REG_CLR);
+
+	/*
+	 * prepare the delay/loop unit according to the oversampling count
+	 *
+	 * from the datasheet:
+	 * "The DELAY fields in HW_LRADC_DELAY0, HW_LRADC_DELAY1,
+	 * HW_LRADC_DELAY2, and HW_LRADC_DELAY3 must be non-zero; otherwise,
+	 * the LRADC will not trigger the delay group."
+	 */
+	writel(LRADC_DELAY_TRIGGER(1 << ch) | LRADC_DELAY_TRIGGER_DELAYS(0) |
+	       LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
+	       LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
+	       ts->base + LRADC_DELAY(3));
+
+	writel(LRADC_CTRL1_LRADC_IRQ(ch),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+
+	/*
+	 * after changing the touchscreen plates setting
+	 * the signals need some initial time to settle. Start the
+	 * SoC's delay unit and start the conversion later
+	 * and automatically.
+	 */
+	writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
+	       LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
+	       ts->base + LRADC_DELAY(2));
+}
+
+/*
+ * Pressure detection is special:
+ * We want to do both required measurements for the pressure detection in
+ * one turn. Use the hardware features to chain both conversions and let the
+ * hardware report one interrupt if both conversions are done
+ */
+static void mxs_lradc_setup_ts_pressure(struct mxs_lradc_ts *ts,
+					unsigned int ch1, unsigned int ch2)
+{
+	u32 reg;
+
+	/*
+	 * prepare for oversampling conversion
+	 *
+	 * from the datasheet:
+	 * "The ACCUMULATE bit in the appropriate channel register
+	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
+	 * otherwise, the IRQs will not fire."
+	 */
+	reg = LRADC_CH_ACCUMULATE |
+		LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1);
+	writel(reg, ts->base + LRADC_CH(ch1));
+	writel(reg, ts->base + LRADC_CH(ch2));
+
+	/* from the datasheet:
+	 * "Software must clear this register in preparation for a
+	 * multi-cycle accumulation.
+	 */
+	writel(LRADC_CH_VALUE_MASK,
+	       ts->base + LRADC_CH(ch1) + STMP_OFFSET_REG_CLR);
+	writel(LRADC_CH_VALUE_MASK,
+	       ts->base + LRADC_CH(ch2) + STMP_OFFSET_REG_CLR);
+
+	/* prepare the delay/loop unit according to the oversampling count */
+	writel(LRADC_DELAY_TRIGGER(1 << ch1) | LRADC_DELAY_TRIGGER(1 << ch2) |
+	       LRADC_DELAY_TRIGGER_DELAYS(0) |
+	       LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
+	       LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
+	       ts->base + LRADC_DELAY(3));
+
+	writel(LRADC_CTRL1_LRADC_IRQ(ch2),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+
+	/*
+	 * after changing the touchscreen plates setting
+	 * the signals need some initial time to settle. Start the
+	 * SoC's delay unit and start the conversion later
+	 * and automatically.
+	 */
+	writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
+	       LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
+	       ts->base + LRADC_DELAY(2));
+}
+
+static unsigned int mxs_lradc_ts_read_raw_channel(struct mxs_lradc_ts *ts,
+						  unsigned int channel)
+{
+	u32 reg;
+	unsigned int num_samples, val;
+
+	reg = readl(ts->base + LRADC_CH(channel));
+	if (reg & LRADC_CH_ACCUMULATE)
+		num_samples = ts->over_sample_cnt;
+	else
+		num_samples = 1;
+
+	val = (reg & LRADC_CH_VALUE_MASK) >> LRADC_CH_VALUE_OFFSET;
+	return val / num_samples;
+}
+
+static unsigned int mxs_lradc_read_ts_pressure(struct mxs_lradc_ts *ts,
+					unsigned int ch1, unsigned int ch2)
+{
+	u32 reg, mask;
+	unsigned int pressure, m1, m2;
+
+	mask = LRADC_CTRL1_LRADC_IRQ(ch1) | LRADC_CTRL1_LRADC_IRQ(ch2);
+	reg = readl(ts->base + LRADC_CTRL1) & mask;
+
+	while (reg != mask) {
+		reg = readl(ts->base + LRADC_CTRL1) & mask;
+		dev_dbg(ts->dev, "One channel is still busy: %X\n", reg);
+	}
+
+	m1 = mxs_lradc_ts_read_raw_channel(ts, ch1);
+	m2 = mxs_lradc_ts_read_raw_channel(ts, ch2);
+
+	if (m2 == 0) {
+		dev_warn(ts->dev, "Cannot calculate pressure\n");
+		return 1 << (LRADC_RESOLUTION - 1);
+	}
+
+	/* simply scale the value from 0 ... max ADC resolution */
+	pressure = m1;
+	pressure *= (1 << LRADC_RESOLUTION);
+	pressure /= m2;
+
+	dev_dbg(ts->dev, "Pressure = %u\n", pressure);
+	return pressure;
+}
+
+#define TS_CH_XP 2
+#define TS_CH_YP 3
+#define TS_CH_XM 4
+#define TS_CH_YM 5
+
+/*
+ * YP(open)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ *    YM(-)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	   XP(weak+)	    XM(open)
+ *
+ * "weak+" means 200k Ohm VDDIO
+ * (-) means GND
+ */
+static void mxs_lradc_setup_touch_detection(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/*
+	 * In order to detect a touch event the 'touch detect enable' bit
+	 * enables:
+	 *  - a weak pullup to the X+ connector
+	 *  - a strong ground at the Y- connector
+	 */
+	writel(info[lradc->soc].mask,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+	writel(info[lradc->soc].bit,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+}
+
+/*
+ * YP(meas)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ * YM(open)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	     XP(+)	    XM(-)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_x_pos(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	writel(info[lradc->soc].mask,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+	writel(info[lradc->soc].x_plate,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+
+	ts->cur_plate = LRADC_SAMPLE_X;
+	mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_YP);
+	mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
+}
+
+/*
+ *   YP(+)--+-------------+
+ *	    |		  |--+
+ *	    |		  |  |
+ *   YM(-)--+-------------+  |
+ *	      +--------------+
+ *	      |		     |
+ *	   XP(open)	   XM(meas)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_y_pos(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	writel(info[lradc->soc].mask,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+	writel(info[lradc->soc].y_plate,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+
+	ts->cur_plate = LRADC_SAMPLE_Y;
+	mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_XM);
+	mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
+}
+
+/*
+ *    YP(+)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ * YM(meas)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	    XP(meas)	    XM(-)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_pressure(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	writel(info[lradc->soc].mask,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+	writel(info[lradc->soc].pressure,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+
+	ts->cur_plate = LRADC_SAMPLE_PRESSURE;
+	mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_YM);
+	mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL2, TS_CH_XP);
+	mxs_lradc_setup_ts_pressure(ts, TOUCHSCREEN_VCHANNEL2,
+				    TOUCHSCREEN_VCHANNEL1);
+}
+
+static void mxs_lradc_enable_touch_detection(struct mxs_lradc_ts *ts)
+{
+	mxs_lradc_setup_touch_detection(ts);
+
+	ts->cur_plate = LRADC_TOUCH;
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ | LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
+}
+
+static void mxs_lradc_start_touch_event(struct mxs_lradc_ts *ts)
+{
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+	writel(LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
+	/*
+	 * start with the Y-pos, because it uses nearly the same plate
+	 * settings like the touch detection
+	 */
+	mxs_lradc_prepare_y_pos(ts);
+}
+
+static void mxs_lradc_report_ts_event(struct mxs_lradc_ts *ts)
+{
+	input_report_abs(ts->ts_input, ABS_X, ts->ts_x_pos);
+	input_report_abs(ts->ts_input, ABS_Y, ts->ts_y_pos);
+	input_report_abs(ts->ts_input, ABS_PRESSURE, ts->ts_pressure);
+	input_report_key(ts->ts_input, BTN_TOUCH, 1);
+	input_sync(ts->ts_input);
+}
+
+static void mxs_lradc_complete_touch_event(struct mxs_lradc_ts *ts)
+{
+	mxs_lradc_setup_touch_detection(ts);
+	ts->cur_plate = LRADC_SAMPLE_VALID;
+	/*
+	 * start a dummy conversion to burn time to settle the signals
+	 * note: we are not interested in the conversion's value
+	 */
+	writel(0, ts->base + LRADC_CH(TOUCHSCREEN_VCHANNEL1));
+	writel(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+	       LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+	writel(LRADC_DELAY_TRIGGER(1 << TOUCHSCREEN_VCHANNEL1) |
+	       LRADC_DELAY_KICK | LRADC_DELAY_DELAY(10),
+	       ts->base + LRADC_DELAY(2));
+}
+
+/*
+ * in order to avoid false measurements, report only samples where
+ * the surface is still touched after the position measurement
+ */
+static void mxs_lradc_finish_touch_event(struct mxs_lradc_ts *ts, bool valid)
+{
+	/* if it is still touched, report the sample */
+	if (valid && mxs_lradc_check_touch_event(ts)) {
+		ts->ts_valid = true;
+		mxs_lradc_report_ts_event(ts);
+	}
+
+	/* if it is even still touched, continue with the next measurement */
+	if (mxs_lradc_check_touch_event(ts)) {
+		mxs_lradc_prepare_y_pos(ts);
+		return;
+	}
+
+	if (ts->ts_valid) {
+		/* signal the release */
+		ts->ts_valid = false;
+		input_report_key(ts->ts_input, BTN_TOUCH, 0);
+		input_sync(ts->ts_input);
+	}
+
+	/* if it is released, wait for the next touch via IRQ */
+	ts->cur_plate = LRADC_TOUCH;
+	writel(0, ts->base + LRADC_DELAY(2));
+	writel(0, ts->base + LRADC_DELAY(3));
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ |
+	       LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
+	       LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_SET);
+}
+
+/* touchscreen's state machine */
+static void mxs_lradc_handle_touch(struct mxs_lradc_ts *ts)
+{
+	switch (ts->cur_plate) {
+	case LRADC_TOUCH:
+		if (mxs_lradc_check_touch_event(ts))
+			mxs_lradc_start_touch_event(ts);
+		writel(LRADC_CTRL1_TOUCH_DETECT_IRQ,
+		       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+		return;
+
+	case LRADC_SAMPLE_Y:
+		ts->ts_y_pos =
+		    mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_prepare_x_pos(ts);
+		return;
+
+	case LRADC_SAMPLE_X:
+		ts->ts_x_pos =
+		    mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_prepare_pressure(ts);
+		return;
+
+	case LRADC_SAMPLE_PRESSURE:
+		ts->ts_pressure =
+		    mxs_lradc_read_ts_pressure(ts,
+					       TOUCHSCREEN_VCHANNEL2,
+					       TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_complete_touch_event(ts);
+		return;
+
+	case LRADC_SAMPLE_VALID:
+		mxs_lradc_finish_touch_event(ts, 1);
+		break;
+	}
+}
+
+/* IRQ Handling */
+static irqreturn_t mxs_lradc_ts_handle_irq(int irq, void *data)
+{
+	struct mxs_lradc_ts *ts = data;
+	struct mxs_lradc *lradc = ts->lradc;
+	unsigned long reg = readl(ts->base + LRADC_CTRL1);
+	u32 clr_irq = mxs_lradc_irq_mask(lradc);
+	const u32 ts_irq_mask =
+		LRADC_CTRL1_TOUCH_DETECT_IRQ |
+		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2);
+	unsigned long flags;
+
+	if (!(reg & mxs_lradc_irq_mask(lradc)))
+		return IRQ_NONE;
+
+	if (reg & ts_irq_mask) {
+		spin_lock_irqsave(&ts->lock, flags);
+		mxs_lradc_handle_touch(ts);
+		spin_unlock_irqrestore(&ts->lock, flags);
+		/* Make sure we don't clear the next conversion's interrupt. */
+		clr_irq &= ~(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+				LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2));
+		writel(reg & clr_irq,
+		       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int mxs_lradc_ts_open(struct input_dev *dev)
+{
+	struct mxs_lradc_ts *ts = input_get_drvdata(dev);
+
+	/* Enable the touch-detect circuitry. */
+	mxs_lradc_enable_touch_detection(ts);
+
+	return 0;
+}
+
+static void mxs_lradc_ts_stop(struct mxs_lradc_ts *ts)
+{
+	int i;
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/* stop all interrupts from firing */
+	writel(LRADC_CTRL1_TOUCH_DETECT_IRQ_EN |
+	       LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
+	       LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL2),
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+
+	/* Power-down touchscreen touch-detect circuitry. */
+	writel(info[lradc->soc].mask,
+	       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+
+	writel(lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+	       ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
+
+	for (i = 1; i < LRADC_MAX_DELAY_CHANS; i++)
+		writel(0, ts->base + LRADC_DELAY(i));
+}
+
+static void mxs_lradc_ts_close(struct input_dev *dev)
+{
+	struct mxs_lradc_ts *ts = input_get_drvdata(dev);
+
+	mxs_lradc_ts_stop(ts);
+}
+
+static void mxs_lradc_ts_hw_init(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/* Configure the touchscreen type */
+	if (lradc->soc == IMX28_LRADC) {
+		writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
+		       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
+
+		if (lradc->touchscreen_wire == MXS_LRADC_TOUCHSCREEN_5WIRE)
+			writel(LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
+			       ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
+	}
+}
+
+static int mxs_lradc_ts_register(struct mxs_lradc_ts *ts)
+{
+	struct input_dev *input = ts->ts_input;
+	struct device *dev = ts->dev;
+
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
+	input->name = "mxs-lradc-ts";
+	input->id.bustype = BUS_HOST;
+	input->open = mxs_lradc_ts_open;
+	input->close = mxs_lradc_ts_close;
+
+	__set_bit(INPUT_PROP_DIRECT, input->propbit);
+	input_set_capability(input, EV_KEY, BTN_TOUCH);
+	input_set_abs_params(input, ABS_X, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_SINGLE_SAMPLE_MASK,
+			     0, 0);
+
+	ts->ts_input = input;
+	input_set_drvdata(input, ts);
+
+	return input_register_device(input);
+}
+
+static int mxs_lradc_ts_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->parent->of_node;
+	struct mxs_lradc *lradc = dev_get_drvdata(dev->parent);
+	struct mxs_lradc_ts *ts;
+	struct resource *iores;
+	int ret, irq, virq, i;
+	u32 ts_wires = 0, adapt;
+
+	ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ts);
+
+	ts->lradc = lradc;
+	ts->dev = dev;
+	spin_lock_init(&ts->lock);
+
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ts->base = devm_ioremap(dev, iores->start, resource_size(iores));
+	if (IS_ERR(ts->base))
+		return PTR_ERR(ts->base);
+
+	ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
+				   &ts_wires);
+	if (ret)
+		return ret;
+
+	if (of_property_read_u32(node, "fsl,ave-ctrl", &adapt)) {
+		ts->over_sample_cnt = 4;
+	} else {
+		if (adapt >= 1 || adapt <= 32) {
+			ts->over_sample_cnt = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid sample count (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	if (of_property_read_u32(node, "fsl,ave-delay", &adapt)) {
+		ts->over_sample_delay = 2;
+	} else {
+		if (adapt >= 2 || adapt <= LRADC_DELAY_DELAY_MASK + 1) {
+			ts->over_sample_delay = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid sample delay (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	if (of_property_read_u32(node, "fsl,settling", &adapt)) {
+		ts->settling_delay = 10;
+	} else {
+		if (adapt >= 1 || adapt <= LRADC_DELAY_DELAY_MASK) {
+			ts->settling_delay = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid settling delay (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	ret = stmp_reset_block(ts->base);
+	if (ret)
+		return ret;
+
+	mxs_lradc_ts_hw_init(ts);
+
+	for (i = 0; i < 3; i++) {
+		irq = platform_get_irq_byname(pdev, mxs_lradc_ts_irq_names[i]);
+		if (irq < 0)
+			return irq;
+
+		virq = irq_of_parse_and_map(node, irq);
+
+		mxs_lradc_ts_stop(ts);
+
+		ret = devm_request_irq(dev, virq,
+				       mxs_lradc_ts_handle_irq,
+				       0, mxs_lradc_ts_irq_names[i], ts);
+		if (ret)
+			return ret;
+	}
+
+	return mxs_lradc_ts_register(ts);
+}
+
+static struct platform_driver mxs_lradc_ts_driver = {
+	.driver	= {
+		.name = "mxs-lradc-ts",
+	},
+	.probe	= mxs_lradc_ts_probe,
+};
+module_platform_driver(mxs_lradc_ts_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("Freescale MXS LRADC touchscreen driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mxs-lradc-ts");
-- 
1.9.1

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#1603084

FromStefan Wahren <stefan.wahren@i2se.com>
Date2017-03-17 08:10 +0100
Message-ID<tlUbo-2o9-13@gated-at.bofh.it>
In reply to#1602231
> Ksenija Stanojevic <ksenija.stanojevic@gmail.com> hat am 16. März 2017 um 13:27 geschrieben:
> 
> 
> Split existing driver mxs-lradc into MFD with touchscreen and
> IIO part.
> 
> Tested on I.MX28
> 
> Ksenija Stanojevic (5):
>   mfd: mxs-lradc: Add support for mxs-lradc MFD
>   iio: adc: mxs-lradc: Add support for adc driver
>   input: touchscreen: mxs-lradc: Add support for touchscreen
>   iio: adc: mxs-lradc: Remove driver
>   mfd: Move binding document
> 

Please add my

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>

for Patch 1 and 2 :)

Regarding to patch 5 i'm not sure. Shouldn't this go through the DT instead of the mfd tree? Unfortunately the DT maintainers aren't in CC and their ACKs are still missing.

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#1603961

FromJonathan Cameron <jic23@kernel.org>
Date2017-03-19 12:20 +0100
Message-ID<tmH2p-4Qu-1@gated-at.bofh.it>
In reply to#1602231
On 16/03/17 12:27, Ksenija Stanojevic wrote:
> Split existing driver mxs-lradc into MFD with touchscreen and
> IIO part.
> 
> Tested on I.MX28
Lee, I've been assuming you will take this one as an immutable branch
in mfd, but let me know if you want it to go another route.

Jonathan
> 
> Ksenija Stanojevic (5):
>   mfd: mxs-lradc: Add support for mxs-lradc MFD
>   iio: adc: mxs-lradc: Add support for adc driver
>   input: touchscreen: mxs-lradc: Add support for touchscreen
>   iio: adc: mxs-lradc: Remove driver
>   mfd: Move binding document
> 
>  .../bindings/{iio/adc => mfd}/mxs-lradc.txt        |    0
>  drivers/iio/adc/Kconfig                            |   27 +-
>  drivers/iio/adc/Makefile                           |    2 +-
>  drivers/iio/adc/mxs-lradc-adc.c                    |  843 ++++++++++
>  drivers/iio/adc/mxs-lradc.c                        | 1750 --------------------
>  drivers/input/touchscreen/Kconfig                  |   10 +
>  drivers/input/touchscreen/Makefile                 |    1 +
>  drivers/input/touchscreen/mxs-lradc-ts.c           |  714 ++++++++
>  drivers/mfd/Kconfig                                |   17 +
>  drivers/mfd/Makefile                               |    1 +
>  drivers/mfd/mxs-lradc.c                            |  267 +++
>  include/linux/mfd/mxs-lradc.h                      |  187 +++
>  12 files changed, 2054 insertions(+), 1765 deletions(-)
>  rename Documentation/devicetree/bindings/{iio/adc => mfd}/mxs-lradc.txt (100%)
>  create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
>  delete mode 100644 drivers/iio/adc/mxs-lradc.c
>  create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
>  create mode 100644 drivers/mfd/mxs-lradc.c
>  create mode 100644 include/linux/mfd/mxs-lradc.h
>

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#1604423

FromLee Jones <lee.jones@linaro.org>
Date2017-03-20 12:40 +0100
Message-ID<tn3Pj-42Z-3@gated-at.bofh.it>
In reply to#1603961
On Sun, 19 Mar 2017, Jonathan Cameron wrote:

> On 16/03/17 12:27, Ksenija Stanojevic wrote:
> > Split existing driver mxs-lradc into MFD with touchscreen and
> > IIO part.
> > 
> > Tested on I.MX28
> Lee, I've been assuming you will take this one as an immutable branch
> in mfd, but let me know if you want it to go another route.

Yes, I'll get around to it.

> > Ksenija Stanojevic (5):
> >   mfd: mxs-lradc: Add support for mxs-lradc MFD
> >   iio: adc: mxs-lradc: Add support for adc driver
> >   input: touchscreen: mxs-lradc: Add support for touchscreen
> >   iio: adc: mxs-lradc: Remove driver
> >   mfd: Move binding document
> > 
> >  .../bindings/{iio/adc => mfd}/mxs-lradc.txt        |    0
> >  drivers/iio/adc/Kconfig                            |   27 +-
> >  drivers/iio/adc/Makefile                           |    2 +-
> >  drivers/iio/adc/mxs-lradc-adc.c                    |  843 ++++++++++
> >  drivers/iio/adc/mxs-lradc.c                        | 1750 --------------------
> >  drivers/input/touchscreen/Kconfig                  |   10 +
> >  drivers/input/touchscreen/Makefile                 |    1 +
> >  drivers/input/touchscreen/mxs-lradc-ts.c           |  714 ++++++++
> >  drivers/mfd/Kconfig                                |   17 +
> >  drivers/mfd/Makefile                               |    1 +
> >  drivers/mfd/mxs-lradc.c                            |  267 +++
> >  include/linux/mfd/mxs-lradc.h                      |  187 +++
> >  12 files changed, 2054 insertions(+), 1765 deletions(-)
> >  rename Documentation/devicetree/bindings/{iio/adc => mfd}/mxs-lradc.txt (100%)
> >  create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
> >  delete mode 100644 drivers/iio/adc/mxs-lradc.c
> >  create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
> >  create mode 100644 drivers/mfd/mxs-lradc.c
> >  create mode 100644 include/linux/mfd/mxs-lradc.h
> > 
> 

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

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#1607441 — [GIT PULL] Immutable branch between MFD, IIO and Input due for the v4.12 merge window

FromLee Jones <lee.jones@linaro.org>
Date2017-03-23 13:40 +0100
Subject[GIT PULL] Immutable branch between MFD, IIO and Input due for the v4.12 merge window
Message-ID<toac2-2e7-13@gated-at.bofh.it>
In reply to#1602231
Enjoy!

The following changes since commit c1ae3cfa0e89fa1a7ecc4c99031f5e9ae99d9201:

  Linux 4.11-rc1 (2017-03-05 12:59:56 -0800)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git ib-mfd-iio-input-v4.12

for you to fetch changes up to b2d476404601806c5a94a5f9bfc441d3898a5541:

  dt-bindings: mfd: Move mxs-lradc binding document from IIO to MFD (2017-03-23 12:29:29 +0000)

----------------------------------------------------------------
Immutable branch between MFD, IIO and Input due for the v4.12 merge window

----------------------------------------------------------------
Ksenija Stanojevic (5):
      mfd: mxs-lradc: Add support for mxs-lradc
      iio: adc: mxs-lradc: Add support for ADC driver
      input: touchscreen: mxs-lradc: Add support for touchscreen
      iio: adc: mxs-lradc: Remove driver
      dt-bindings: mfd: Move mxs-lradc binding document from IIO to MFD

 .../bindings/{iio/adc => mfd}/mxs-lradc.txt        |    0
 drivers/iio/adc/Kconfig                            |   27 +-
 drivers/iio/adc/Makefile                           |    2 +-
 drivers/iio/adc/mxs-lradc-adc.c                    |  843 ++++++++++
 drivers/iio/adc/mxs-lradc.c                        | 1750 --------------------
 drivers/input/touchscreen/Kconfig                  |   10 +
 drivers/input/touchscreen/Makefile                 |    1 +
 drivers/input/touchscreen/mxs-lradc-ts.c           |  714 ++++++++
 drivers/mfd/Kconfig                                |   17 +
 drivers/mfd/Makefile                               |    1 +
 drivers/mfd/mxs-lradc.c                            |  267 +++
 include/linux/mfd/mxs-lradc.h                      |  187 +++
 12 files changed, 2054 insertions(+), 1765 deletions(-)
 rename Documentation/devicetree/bindings/{iio/adc => mfd}/mxs-lradc.txt (100%)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
 delete mode 100644 drivers/iio/adc/mxs-lradc.c
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

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