2017-03-16 06:27:11 -06:00
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/*
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* Freescale MXS LRADC touchscreen driver
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*
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* Copyright (c) 2012 DENX Software Engineering, GmbH.
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* Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
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*
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* Authors:
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* Marek Vasut <marex@denx.de>
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* Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/input.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/mfd/core.h>
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#include <linux/mfd/mxs-lradc.h>
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#include <linux/of.h>
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#include <linux/of_irq.h>
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#include <linux/platform_device.h>
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2017-08-14 11:31:13 -06:00
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static const char * const mxs_lradc_ts_irq_names[] = {
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2017-03-16 06:27:11 -06:00
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"mxs-lradc-touchscreen",
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"mxs-lradc-channel6",
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"mxs-lradc-channel7",
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};
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/*
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* Touchscreen handling
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*/
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enum mxs_lradc_ts_plate {
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LRADC_TOUCH = 0,
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LRADC_SAMPLE_X,
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LRADC_SAMPLE_Y,
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LRADC_SAMPLE_PRESSURE,
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LRADC_SAMPLE_VALID,
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};
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struct mxs_lradc_ts {
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struct mxs_lradc *lradc;
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struct device *dev;
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void __iomem *base;
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/*
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* When the touchscreen is enabled, we give it two private virtual
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* channels: #6 and #7. This means that only 6 virtual channels (instead
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* of 8) will be available for buffered capture.
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*/
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#define TOUCHSCREEN_VCHANNEL1 7
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#define TOUCHSCREEN_VCHANNEL2 6
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struct input_dev *ts_input;
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enum mxs_lradc_ts_plate cur_plate; /* state machine */
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bool ts_valid;
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unsigned int ts_x_pos;
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unsigned int ts_y_pos;
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unsigned int ts_pressure;
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/* handle touchscreen's physical behaviour */
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/* samples per coordinate */
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unsigned int over_sample_cnt;
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/* time clocks between samples */
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unsigned int over_sample_delay;
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/* time in clocks to wait after the plates where switched */
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unsigned int settling_delay;
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spinlock_t lock;
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};
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struct state_info {
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u32 mask;
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u32 bit;
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u32 x_plate;
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u32 y_plate;
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u32 pressure;
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};
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static struct state_info info[] = {
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{LRADC_CTRL0_MX23_PLATE_MASK, LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE,
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LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM,
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LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM,
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LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM},
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{LRADC_CTRL0_MX28_PLATE_MASK, LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE,
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LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW,
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LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW,
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LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW}
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};
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static bool mxs_lradc_check_touch_event(struct mxs_lradc_ts *ts)
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{
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return !!(readl(ts->base + LRADC_STATUS) &
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LRADC_STATUS_TOUCH_DETECT_RAW);
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}
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static void mxs_lradc_map_ts_channel(struct mxs_lradc_ts *ts, unsigned int vch,
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unsigned int ch)
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{
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writel(LRADC_CTRL4_LRADCSELECT_MASK(vch),
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ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_CLR);
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writel(LRADC_CTRL4_LRADCSELECT(vch, ch),
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ts->base + LRADC_CTRL4 + STMP_OFFSET_REG_SET);
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}
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static void mxs_lradc_setup_ts_channel(struct mxs_lradc_ts *ts, unsigned int ch)
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{
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/*
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* prepare for oversampling conversion
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*
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* from the datasheet:
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* "The ACCUMULATE bit in the appropriate channel register
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* HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
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* otherwise, the IRQs will not fire."
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*/
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writel(LRADC_CH_ACCUMULATE |
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LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1),
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ts->base + LRADC_CH(ch));
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/* from the datasheet:
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* "Software must clear this register in preparation for a
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* multi-cycle accumulation.
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*/
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writel(LRADC_CH_VALUE_MASK,
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ts->base + LRADC_CH(ch) + STMP_OFFSET_REG_CLR);
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/*
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* prepare the delay/loop unit according to the oversampling count
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*
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* from the datasheet:
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* "The DELAY fields in HW_LRADC_DELAY0, HW_LRADC_DELAY1,
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* HW_LRADC_DELAY2, and HW_LRADC_DELAY3 must be non-zero; otherwise,
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* the LRADC will not trigger the delay group."
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*/
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writel(LRADC_DELAY_TRIGGER(1 << ch) | LRADC_DELAY_TRIGGER_DELAYS(0) |
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LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
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LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
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ts->base + LRADC_DELAY(3));
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writel(LRADC_CTRL1_LRADC_IRQ(ch),
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ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
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/*
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* after changing the touchscreen plates setting
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* the signals need some initial time to settle. Start the
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* SoC's delay unit and start the conversion later
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* and automatically.
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*/
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writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
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LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
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ts->base + LRADC_DELAY(2));
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}
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/*
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* Pressure detection is special:
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* We want to do both required measurements for the pressure detection in
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* one turn. Use the hardware features to chain both conversions and let the
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* hardware report one interrupt if both conversions are done
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*/
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static void mxs_lradc_setup_ts_pressure(struct mxs_lradc_ts *ts,
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unsigned int ch1, unsigned int ch2)
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{
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u32 reg;
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/*
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* prepare for oversampling conversion
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*
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* from the datasheet:
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* "The ACCUMULATE bit in the appropriate channel register
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* HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
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* otherwise, the IRQs will not fire."
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*/
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reg = LRADC_CH_ACCUMULATE |
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LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1);
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writel(reg, ts->base + LRADC_CH(ch1));
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writel(reg, ts->base + LRADC_CH(ch2));
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/* from the datasheet:
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* "Software must clear this register in preparation for a
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* multi-cycle accumulation.
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*/
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writel(LRADC_CH_VALUE_MASK,
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ts->base + LRADC_CH(ch1) + STMP_OFFSET_REG_CLR);
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writel(LRADC_CH_VALUE_MASK,
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ts->base + LRADC_CH(ch2) + STMP_OFFSET_REG_CLR);
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/* prepare the delay/loop unit according to the oversampling count */
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writel(LRADC_DELAY_TRIGGER(1 << ch1) | LRADC_DELAY_TRIGGER(1 << ch2) |
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LRADC_DELAY_TRIGGER_DELAYS(0) |
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LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
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LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
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ts->base + LRADC_DELAY(3));
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writel(LRADC_CTRL1_LRADC_IRQ(ch2),
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ts->base + LRADC_CTRL1 + STMP_OFFSET_REG_CLR);
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/*
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* after changing the touchscreen plates setting
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* the signals need some initial time to settle. Start the
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* SoC's delay unit and start the conversion later
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* and automatically.
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*/
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writel(LRADC_DELAY_TRIGGER(0) | LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) |
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LRADC_DELAY_KICK | LRADC_DELAY_DELAY(ts->settling_delay),
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ts->base + LRADC_DELAY(2));
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}
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static unsigned int mxs_lradc_ts_read_raw_channel(struct mxs_lradc_ts *ts,
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unsigned int channel)
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{
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u32 reg;
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unsigned int num_samples, val;
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reg = readl(ts->base + LRADC_CH(channel));
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if (reg & LRADC_CH_ACCUMULATE)
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num_samples = ts->over_sample_cnt;
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else
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num_samples = 1;
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val = (reg & LRADC_CH_VALUE_MASK) >> LRADC_CH_VALUE_OFFSET;
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return val / num_samples;
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}
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static unsigned int mxs_lradc_read_ts_pressure(struct mxs_lradc_ts *ts,
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unsigned int ch1, unsigned int ch2)
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{
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u32 reg, mask;
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unsigned int pressure, m1, m2;
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mask = LRADC_CTRL1_LRADC_IRQ(ch1) | LRADC_CTRL1_LRADC_IRQ(ch2);
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reg = readl(ts->base + LRADC_CTRL1) & mask;
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while (reg != mask) {
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reg = readl(ts->base + LRADC_CTRL1) & mask;
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dev_dbg(ts->dev, "One channel is still busy: %X\n", reg);
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}
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m1 = mxs_lradc_ts_read_raw_channel(ts, ch1);
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m2 = mxs_lradc_ts_read_raw_channel(ts, ch2);
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if (m2 == 0) {
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dev_warn(ts->dev, "Cannot calculate pressure\n");
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return 1 << (LRADC_RESOLUTION - 1);
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}
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/* simply scale the value from 0 ... max ADC resolution */
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pressure = m1;
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pressure *= (1 << LRADC_RESOLUTION);
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pressure /= m2;
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dev_dbg(ts->dev, "Pressure = %u\n", pressure);
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return pressure;
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}
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#define TS_CH_XP 2
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#define TS_CH_YP 3
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#define TS_CH_XM 4
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#define TS_CH_YM 5
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/*
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* YP(open)--+-------------+
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* | |--+
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* | | |
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* YM(-)--+-------------+ |
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* +--------------+
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* | |
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* XP(weak+) XM(open)
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*
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* "weak+" means 200k Ohm VDDIO
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* (-) means GND
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*/
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static void mxs_lradc_setup_touch_detection(struct mxs_lradc_ts *ts)
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{
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struct mxs_lradc *lradc = ts->lradc;
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/*
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* In order to detect a touch event the 'touch detect enable' bit
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* enables:
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* - a weak pullup to the X+ connector
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* - a strong ground at the Y- connector
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*/
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writel(info[lradc->soc].mask,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
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writel(info[lradc->soc].bit,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
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}
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/*
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* YP(meas)--+-------------+
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* | |--+
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* | | |
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* YM(open)--+-------------+ |
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* +--------------+
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* | |
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* XP(+) XM(-)
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*
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* (+) means here 1.85 V
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* (-) means here GND
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*/
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static void mxs_lradc_prepare_x_pos(struct mxs_lradc_ts *ts)
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{
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struct mxs_lradc *lradc = ts->lradc;
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writel(info[lradc->soc].mask,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
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writel(info[lradc->soc].x_plate,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
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ts->cur_plate = LRADC_SAMPLE_X;
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mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_YP);
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mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
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}
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/*
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* YP(+)--+-------------+
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* | |--+
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* | | |
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* YM(-)--+-------------+ |
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* +--------------+
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* | |
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* XP(open) XM(meas)
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*
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* (+) means here 1.85 V
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* (-) means here GND
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*/
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static void mxs_lradc_prepare_y_pos(struct mxs_lradc_ts *ts)
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{
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struct mxs_lradc *lradc = ts->lradc;
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writel(info[lradc->soc].mask,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_CLR);
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writel(info[lradc->soc].y_plate,
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ts->base + LRADC_CTRL0 + STMP_OFFSET_REG_SET);
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ts->cur_plate = LRADC_SAMPLE_Y;
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mxs_lradc_map_ts_channel(ts, TOUCHSCREEN_VCHANNEL1, TS_CH_XM);
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mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
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}
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/*
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* YP(+)--+-------------+
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|
|
* | |--+
|
|
|
|
* | | |
|
|
|
|
* 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);
|
2017-08-14 11:26:27 -06:00
|
|
|
if (!iores)
|
|
|
|
return -EINVAL;
|
2017-03-16 06:27:11 -06:00
|
|
|
ts->base = devm_ioremap(dev, iores->start, resource_size(iores));
|
2017-08-14 11:29:13 -06:00
|
|
|
if (!ts->base)
|
|
|
|
return -ENOMEM;
|
2017-03-16 06:27:11 -06:00
|
|
|
|
|
|
|
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 {
|
2017-04-26 15:04:31 -06:00
|
|
|
if (adapt >= 1 && adapt <= 32) {
|
2017-03-16 06:27:11 -06:00
|
|
|
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 {
|
2017-04-26 15:04:31 -06:00
|
|
|
if (adapt >= 2 && adapt <= LRADC_DELAY_DELAY_MASK + 1) {
|
2017-03-16 06:27:11 -06:00
|
|
|
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 {
|
2017-04-26 15:04:31 -06:00
|
|
|
if (adapt >= 1 && adapt <= LRADC_DELAY_DELAY_MASK) {
|
2017-03-16 06:27:11 -06:00
|
|
|
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");
|