Re: [PATCH v2 1/5] input: touchscreen: add imx6ul_tsc driver support

From: Dmitry Torokhov
Date: Wed Aug 19 2015 - 01:11:44 EST


Hi Haibo,

On Tue, Jul 28, 2015 at 05:58:37PM +0800, Haibo Chen wrote:
> Freescale i.MX6UL contains a internal touchscreen controller,
> this patch add a driver to support this controller.
>

This looks pretty reasonable; just a few comments below.

> Signed-off-by: Haibo Chen <haibo.chen@xxxxxxxxxxxxx>
> ---
> drivers/input/touchscreen/Kconfig | 12 +
> drivers/input/touchscreen/Makefile | 1 +
> drivers/input/touchscreen/imx6ul_tsc.c | 504 +++++++++++++++++++++++++++++++++
> 3 files changed, 517 insertions(+)
> create mode 100644 drivers/input/touchscreen/imx6ul_tsc.c
>
> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> index 5b272ba..32c300d 100644
> --- a/drivers/input/touchscreen/Kconfig
> +++ b/drivers/input/touchscreen/Kconfig
> @@ -479,6 +479,18 @@ config TOUCHSCREEN_MTOUCH
> To compile this driver as a module, choose M here: the
> module will be called mtouch.
>
> +config TOUCHSCREEN_IMX6UL_TSC
> + tristate "Freescale i.MX6UL touchscreen controller"
> + depends on OF
> + help
> + Say Y here if you have a Freescale i.MX6UL, and want to
> + use the internal touchscreen controller.
> +
> + If unsure, say N.
> +
> + To compile this driver as a module, choose M here: the
> + moduel will be called imx6ul_tsc.
> +
> config TOUCHSCREEN_INEXIO
> tristate "iNexio serial touchscreens"
> select SERIO
> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
> index c85aae2..9379b32 100644
> --- a/drivers/input/touchscreen/Makefile
> +++ b/drivers/input/touchscreen/Makefile
> @@ -38,6 +38,7 @@ obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o
> obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o
> obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix.o
> obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o
> +obj-$(CONFIG_TOUCHSCREEN_IMX6UL_TSC) += imx6ul_tsc.o
> obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o
> obj-$(CONFIG_TOUCHSCREEN_INTEL_MID) += intel-mid-touch.o
> obj-$(CONFIG_TOUCHSCREEN_IPROC) += bcm_iproc_tsc.o
> diff --git a/drivers/input/touchscreen/imx6ul_tsc.c b/drivers/input/touchscreen/imx6ul_tsc.c
> new file mode 100644
> index 0000000..807f1db
> --- /dev/null
> +++ b/drivers/input/touchscreen/imx6ul_tsc.c
> @@ -0,0 +1,504 @@
> +/*
> + * Freescale i.MX6UL touchscreen controller driver
> + *
> + * Copyright (C) 2015 Freescale Semiconductor, Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/gpio.h>
> +#include <linux/input.h>
> +#include <linux/slab.h>
> +#include <linux/completion.h>
> +#include <linux/delay.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> +#include <linux/of_irq.h>

I do not think you need of_irq and of_device.

> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +
> +/* ADC configuration registers field define */
> +#define ADC_AIEN (0x1 << 7)
> +#define ADC_CONV_DISABLE 0x1F
> +#define ADC_CAL (0x1 << 7)
> +#define ADC_CALF 0x2
> +#define ADC_12BIT_MODE (0x2 << 2)
> +#define ADC_IPG_CLK 0x00
> +#define ADC_CLK_DIV_8 (0x03 << 5)
> +#define ADC_SHORT_SAMPLE_MODE (0x0 << 4)
> +#define ADC_HARDWARE_TRIGGER (0x1 << 13)
> +#define SELECT_CHANNEL_4 0x04
> +#define SELECT_CHANNEL_1 0x01
> +#define DISABLE_CONVERSION_INT (0x0 << 7)
> +
> +/* ADC registers */
> +#define REG_ADC_HC0 0x00
> +#define REG_ADC_HC1 0x04
> +#define REG_ADC_HC2 0x08
> +#define REG_ADC_HC3 0x0C
> +#define REG_ADC_HC4 0x10
> +#define REG_ADC_HS 0x14
> +#define REG_ADC_R0 0x18
> +#define REG_ADC_CFG 0x2C
> +#define REG_ADC_GC 0x30
> +#define REG_ADC_GS 0x34
> +
> +#define ADC_TIMEOUT msecs_to_jiffies(100)
> +
> +/* TSC registers */
> +#define REG_TSC_BASIC_SETING 0x00
> +#define REG_TSC_PRE_CHARGE_TIME 0x10
> +#define REG_TSC_FLOW_CONTROL 0x20
> +#define REG_TSC_MEASURE_VALUE 0x30
> +#define REG_TSC_INT_EN 0x40
> +#define REG_TSC_INT_SIG_EN 0x50
> +#define REG_TSC_INT_STATUS 0x60
> +#define REG_TSC_DEBUG_MODE 0x70
> +#define REG_TSC_DEBUG_MODE2 0x80
> +
> +/* TSC configuration registers field define */
> +#define DETECT_4_WIRE_MODE (0x0 << 4)
> +#define AUTO_MEASURE 0x1
> +#define MEASURE_SIGNAL 0x1
> +#define DETECT_SIGNAL (0x1 << 4)
> +#define VALID_SIGNAL (0x1 << 8)
> +#define MEASURE_INT_EN 0x1
> +#define MEASURE_SIG_EN 0x1
> +#define VALID_SIG_EN (0x1 << 8)
> +#define DE_GLITCH_2 (0x2 << 29)
> +#define START_SENSE (0x1 << 12)
> +#define TSC_DISABLE (0x1 << 16)
> +#define DETECT_MODE 0x2
> +
> +struct imx6ul_tsc {
> + struct device *dev;
> + struct input_dev *input;
> + void __iomem *tsc_regs;
> + void __iomem *adc_regs;
> + struct clk *tsc_clk;
> + struct clk *adc_clk;
> +
> + int xnur_gpio;
> + int measure_delay_time;
> + int pre_charge_time;
> +
> + struct completion completion;
> +};
> +
> +/*
> + * TSC module need ADC to get the measure value. So
> + * before config TSC, we should initialize ADC module.
> + */
> +static void imx6ul_adc_init(struct imx6ul_tsc *tsc)
> +{
> + int adc_hc = 0;
> + int adc_gc;
> + int adc_gs;
> + int adc_cfg;
> + int timeout;
> +
> + adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
> + adc_cfg |= ADC_12BIT_MODE | ADC_IPG_CLK;
> + adc_cfg |= ADC_CLK_DIV_8 | ADC_SHORT_SAMPLE_MODE;
> + adc_cfg &= ~ADC_HARDWARE_TRIGGER;
> + writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
> +
> + /* enable calibration interrupt */
> + adc_hc |= ADC_AIEN;
> + adc_hc |= ADC_CONV_DISABLE;
> + writel(adc_hc, tsc->adc_regs + REG_ADC_HC0);
> +
> + /* start ADC calibration */
> + adc_gc = readl(tsc->adc_regs + REG_ADC_GC);
> + adc_gc |= ADC_CAL;
> + writel(adc_gc, tsc->adc_regs + REG_ADC_GC);
> +

Since this is called on every resume you need to reinit completion;
probably at the beginning of this function.

> + timeout = wait_for_completion_timeout
> + (&tsc->completion, ADC_TIMEOUT);
> + if (timeout == 0)
> + dev_err(tsc->dev, "Timeout for adc calibration\n");
> +
> + adc_gs = readl(tsc->adc_regs + REG_ADC_GS);
> + if (adc_gs & ADC_CALF)
> + dev_err(tsc->dev, "ADC calibration failed\n");
> +
> + /* TSC need the ADC work in hardware trigger */
> + adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
> + adc_cfg |= ADC_HARDWARE_TRIGGER;
> + writel(adc_cfg, tsc->adc_regs + REG_ADC_CFG);
> +}
> +
> +/*
> + * This is a TSC workaround. Currently TSC misconnect two
> + * ADC channels, this function remap channel configure for
> + * hardware trigger.
> + */
> +static void imx6ul_tsc_channel_config(struct imx6ul_tsc *tsc)
> +{
> + int adc_hc0, adc_hc1, adc_hc2, adc_hc3, adc_hc4;
> +
> + adc_hc0 = DISABLE_CONVERSION_INT;
> + writel(adc_hc0, tsc->adc_regs + REG_ADC_HC0);
> +
> + adc_hc1 = DISABLE_CONVERSION_INT | SELECT_CHANNEL_4;
> + writel(adc_hc1, tsc->adc_regs + REG_ADC_HC1);
> +
> + adc_hc2 = DISABLE_CONVERSION_INT;
> + writel(adc_hc2, tsc->adc_regs + REG_ADC_HC2);
> +
> + adc_hc3 = DISABLE_CONVERSION_INT | SELECT_CHANNEL_1;
> + writel(adc_hc3, tsc->adc_regs + REG_ADC_HC3);
> +
> + adc_hc4 = DISABLE_CONVERSION_INT;
> + writel(adc_hc4, tsc->adc_regs + REG_ADC_HC4);
> +}
> +
> +/*
> + * TSC setting, confige the pre-charge time and measure delay time.
> + * different touch screen may need different pre-charge time and
> + * measure delay time.
> + */
> +static void imx6ul_tsc_set(struct imx6ul_tsc *tsc)
> +{
> + int basic_setting = 0;
> + int start;
> +
> + basic_setting |= tsc->measure_delay_time << 8;
> + basic_setting |= DETECT_4_WIRE_MODE | AUTO_MEASURE;
> + writel(basic_setting, tsc->tsc_regs + REG_TSC_BASIC_SETING);
> +
> + writel(DE_GLITCH_2, tsc->tsc_regs + REG_TSC_DEBUG_MODE2);
> +
> + writel(tsc->pre_charge_time, tsc->tsc_regs + REG_TSC_PRE_CHARGE_TIME);
> + writel(MEASURE_INT_EN, tsc->tsc_regs + REG_TSC_INT_EN);
> + writel(MEASURE_SIG_EN | VALID_SIG_EN,
> + tsc->tsc_regs + REG_TSC_INT_SIG_EN);
> +
> + /* start sense detection */
> + start = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> + start |= START_SENSE;
> + start &= ~TSC_DISABLE;
> + writel(start, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> +}
> +
> +static void imx6ul_tsc_init(struct imx6ul_tsc *tsc)
> +{
> + imx6ul_adc_init(tsc);
> + imx6ul_tsc_channel_config(tsc);
> + imx6ul_tsc_set(tsc);
> +}
> +
> +static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
> +{
> + struct imx6ul_tsc *tsc = (struct imx6ul_tsc *)dev_id;

No need to cast void pointers.

> + int status;
> + int value;
> + int x, y;
> + int xnur;
> + int debug_mode2;
> + int state_machine;
> + int start;
> + unsigned long timeout;
> +
> + status = readl(tsc->tsc_regs + REG_TSC_INT_STATUS);
> +
> + /* write 1 to clear the bit measure-signal */
> + writel(MEASURE_SIGNAL | DETECT_SIGNAL,
> + tsc->tsc_regs + REG_TSC_INT_STATUS);
> +
> + /* It's a HW self-clean bit. Set this bit and start sense detection */
> + start = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> + start |= START_SENSE;
> + writel(start, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> +
> + if (status & MEASURE_SIGNAL) {
> + value = readl(tsc->tsc_regs + REG_TSC_MEASURE_VALUE);
> + x = (value >> 16) & 0x0fff;
> + y = value & 0x0fff;
> +
> + /*
> + * Delay some time(max 2ms), wait the pre-charge done.
> + * After the pre-change mode, TSC go into detect mode.
> + * And in detect mode, we can get the xnur gpio value.
> + * If xnur is low, this means the touch screen still
> + * be touched. If xnur is high, this means finger leave
> + * the touch screen.
> + */
> + timeout = jiffies + HZ/500;
> + do {
> + if (time_after(jiffies, timeout)) {
> + xnur = 0;
> + goto touch_event;
> + }
> + usleep_range(200, 400);
> + debug_mode2 = readl(tsc->tsc_regs + REG_TSC_DEBUG_MODE2);
> + state_machine = (debug_mode2 >> 20) & 0x7;
> + } while (state_machine != DETECT_MODE);
> + usleep_range(200, 400);
> +
> + xnur = gpio_get_value(tsc->xnur_gpio);

It seems to me that this GPIO is actually active low: we reporting
active touch as long as we read 0.

> +touch_event:
> + if (xnur == 0) {
> + input_report_key(tsc->input, BTN_TOUCH, 1);
> + input_report_abs(tsc->input, ABS_X, x);
> + input_report_abs(tsc->input, ABS_Y, y);
> + } else
> + input_report_key(tsc->input, BTN_TOUCH, 0);

If one branch has braces all of them should have braces.

> +
> + input_sync(tsc->input);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t adc_irq_fn(int irq, void *dev_id)
> +{
> + struct imx6ul_tsc *tsc = (struct imx6ul_tsc *)dev_id;
> + int coco;
> + int value;
> +
> + coco = readl(tsc->adc_regs + REG_ADC_HS);
> + if (coco & 0x01) {
> + value = readl(tsc->adc_regs + REG_ADC_R0);
> + complete(&tsc->completion);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static const struct of_device_id imx6ul_tsc_match[] = {
> + { .compatible = "fsl,imx6ul-tsc", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx6ul_tsc_match);
> +
> +static int imx6ul_tsc_probe(struct platform_device *pdev)
> +{
> + struct imx6ul_tsc *tsc;
> + struct resource *tsc_mem;
> + struct resource *adc_mem;
> + struct input_dev *input_dev;
> + struct device_node *np = pdev->dev.of_node;
> + int err;
> + int tsc_irq;
> + int adc_irq;
> +
> + tsc = devm_kzalloc(&pdev->dev, sizeof(struct imx6ul_tsc), GFP_KERNEL);
> + input_dev = devm_input_allocate_device(&pdev->dev);

Using devm does not mean you do not need to check results of memory
allocation.

> +
> + tsc->dev = &pdev->dev;
> +
> + tsc->input = input_dev;
> + tsc->input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
> + tsc->input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
> + input_set_abs_params(tsc->input, ABS_X, 0, 0xFFF, 0, 0);
> + input_set_abs_params(tsc->input, ABS_Y, 0, 0xFFF, 0, 0);
> +
> + tsc->input->name = "iMX6UL TouchScreen Controller";
> +
> + tsc->xnur_gpio = of_get_named_gpio(np, "xnur-gpio", 0);
> + err = gpio_request_one(tsc->xnur_gpio, GPIOF_IN, "tsc_X-");

Why are you not using devm for gpio? Actually, why don't you also use
gpiod? As is you are leaking that gpio in all error paths below.

> + if (err) {
> + dev_err(&pdev->dev, "failed to request GPIO tsc_X-\n");
> + return err;
> + }
> +
> + tsc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + tsc->tsc_regs = devm_ioremap_resource(&pdev->dev, tsc_mem);
> + if (IS_ERR(tsc->tsc_regs)) {
> + dev_err(&pdev->dev, "failed to remap tsc memory\n");
> + err = PTR_ERR(tsc->tsc_regs);
> + return err;
> + }
> +
> + adc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> + tsc->adc_regs = devm_ioremap_resource(&pdev->dev, adc_mem);
> + if (IS_ERR(tsc->adc_regs)) {
> + dev_err(&pdev->dev, "failed to remap adc memory\n");
> + err = PTR_ERR(tsc->adc_regs);
> + return err;
> + }
> +
> + tsc->tsc_clk = devm_clk_get(&pdev->dev, "tsc");
> + if (IS_ERR(tsc->tsc_clk)) {
> + dev_err(&pdev->dev, "failed getting tsc clock\n");
> + err = PTR_ERR(tsc->tsc_clk);
> + return err;
> + }
> +
> + tsc->adc_clk = devm_clk_get(&pdev->dev, "adc");
> + if (IS_ERR(tsc->adc_clk)) {
> + dev_err(&pdev->dev, "failed getting adc clock\n");
> + err = PTR_ERR(tsc->adc_clk);
> + return err;
> + }
> +
> + tsc_irq = platform_get_irq(pdev, 0);
> + if (tsc_irq < 0) {
> + dev_err(&pdev->dev, "no tsc irq resource?\n");
> + return tsc_irq;
> + }
> +
> + adc_irq = platform_get_irq(pdev, 1);
> + if (adc_irq <= 0) {
> + dev_err(&pdev->dev, "no adc irq resource?\n");
> + return adc_irq;
> + }
> +
> + err = devm_request_threaded_irq(tsc->dev, tsc_irq,
> + NULL, tsc_irq_fn,
> + IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
> + dev_name(&pdev->dev), tsc);
> + if (err < 0) {
> + dev_err(&pdev->dev,
> + "failed requesting tsc irq %d\n",
> + tsc_irq);
> + return err;
> + }
> +
> + err = devm_request_irq(tsc->dev, adc_irq,
> + adc_irq_fn, 0,
> + dev_name(&pdev->dev), tsc);
> + if (err < 0) {
> + dev_err(&pdev->dev,
> + "failed requesting adc irq %d\n",
> + adc_irq);
> + return err;
> + }
> +
> + err = of_property_read_u32(np, "measure-delay-time",
> + &tsc->measure_delay_time);
> + if (err)
> + tsc->measure_delay_time = 0xffff;
> +
> + err = of_property_read_u32(np, "pre-charge-time",
> + &tsc->pre_charge_time);
> + if (err)
> + tsc->pre_charge_time = 0xfff;
> +
> + init_completion(&tsc->completion);
> +
> + err = clk_prepare_enable(tsc->adc_clk);
> + if (err) {
> + dev_err(&pdev->dev,
> + "Could not prepare or enable the adc clock.\n");
> + return err;
> + }
> +
> + err = clk_prepare_enable(tsc->tsc_clk);
> + if (err) {
> + dev_err(&pdev->dev,
> + "Could not prepare or enable the tsc clock.\n");
> + goto error_tsc_clk_enable;
> + }
> +
> + err = input_register_device(tsc->input);
> + if (err < 0) {
> + dev_err(&pdev->dev, "failed to register input device\n");
> + err = -EIO;
> + goto err_input_register;
> + }
> +
> + imx6ul_tsc_init(tsc);

Enabling clock and initializing the controller is better in open()
method of input device. If you also implement close() you can get rid of
remove().

> +
> + platform_set_drvdata(pdev, tsc);
> + return 0;
> +
> +err_input_register:
> + clk_disable_unprepare(tsc->tsc_clk);
> +error_tsc_clk_enable:
> + clk_disable_unprepare(tsc->adc_clk);
> +
> + return err;
> +}
> +
> +static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
> +{
> + int tsc_flow;
> + int adc_cfg;
> +
> + /* TSC controller enters to idle status */
> + tsc_flow = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> + tsc_flow |= TSC_DISABLE;
> + writel(tsc_flow, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
> +
> + /* ADC controller enters to stop mode */
> + adc_cfg = readl(tsc->adc_regs + REG_ADC_HC0);
> + adc_cfg |= ADC_CONV_DISABLE;
> + writel(adc_cfg, tsc->adc_regs + REG_ADC_HC0);
> +}
> +
> +static int imx6ul_tsc_remove(struct platform_device *pdev)
> +{
> + struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
> +
> + imx6ul_tsc_disable(tsc);
> +
> + clk_disable_unprepare(tsc->tsc_clk);
> + clk_disable_unprepare(tsc->adc_clk);
> + input_unregister_device(tsc->input);
> + kfree(tsc);

Tsc is allocated with devm(), you can't kfree() it.
> +
> + return 0;
> +}
> +
> +static int __maybe_unused imx6ul_tsc_suspend(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
> +
> + imx6ul_tsc_disable(tsc);
> +
> + clk_disable_unprepare(tsc->tsc_clk);
> + clk_disable_unprepare(tsc->adc_clk);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused imx6ul_tsc_resume(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
> + int err;
> +
> + err = clk_prepare_enable(tsc->adc_clk);
> + if (err)
> + return err;
> +
> + err = clk_prepare_enable(tsc->tsc_clk);
> + if (err) {
> + clk_disable_unprepare(tsc->adc_clk);
> + return err;
> + }
> +
> + imx6ul_tsc_init(tsc);
> + return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(imx6ul_tsc_pm_ops,
> + imx6ul_tsc_suspend,
> + imx6ul_tsc_resume);
> +
> +static struct platform_driver imx6ul_tsc_driver = {
> + .driver = {
> + .name = "imx6ul-tsc",
> + .owner = THIS_MODULE,
> + .of_match_table = imx6ul_tsc_match,
> + .pm = &imx6ul_tsc_pm_ops,
> + },
> + .probe = imx6ul_tsc_probe,
> + .remove = imx6ul_tsc_remove,
> +};
> +module_platform_driver(imx6ul_tsc_driver);
> +
> +MODULE_AUTHOR("Haibo Chen <haibo.chen@xxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Freescale i.MX6UL Touchscreen controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1
>

Can you try the patch below and let me know if it still works (you'll
need to adjust your DTS for xnur gpio being active low).

Thanks!

--
Dmitry

Input: imx6ul_tsc - misc changes

From: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
.../bindings/input/touchscreen/imx6ul_tsc.txt | 2
drivers/input/touchscreen/Kconfig | 2
drivers/input/touchscreen/imx6ul_tsc.c | 262 +++++++++++---------
3 files changed, 143 insertions(+), 123 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt
index ac41c32..c933588 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt
@@ -29,7 +29,7 @@ Example:
clock-names = "tsc", "adc";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_tsc>;
- xnur-gpio = <&gpio1 3 GPIO_ACTIVE_HIGH>;
+ xnur-gpio = <&gpio1 3 GPIO_ACTIVE_LOW>;
measure-delay-time = <0xfff>;
pre-charge-time = <0xffff>;
status = "okay";
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 9a1a293..5ecf19b 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -481,7 +481,7 @@ config TOUCHSCREEN_MTOUCH

config TOUCHSCREEN_IMX6UL_TSC
tristate "Freescale i.MX6UL touchscreen controller"
- depends on OF
+ depends on (OF && GPIOLIB) || COMPILE_TEST
help
Say Y here if you have a Freescale i.MX6UL, and want to
use the internal touchscreen controller.
diff --git a/drivers/input/touchscreen/imx6ul_tsc.c b/drivers/input/touchscreen/imx6ul_tsc.c
index 807f1db..1d028ed 100644
--- a/drivers/input/touchscreen/imx6ul_tsc.c
+++ b/drivers/input/touchscreen/imx6ul_tsc.c
@@ -11,15 +11,12 @@
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/of_gpio.h>
-#include <linux/of_irq.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
@@ -85,8 +82,8 @@ struct imx6ul_tsc {
void __iomem *adc_regs;
struct clk *tsc_clk;
struct clk *adc_clk;
+ struct gpio_desc *xnur_gpio;

- int xnur_gpio;
int measure_delay_time;
int pre_charge_time;

@@ -105,6 +102,8 @@ static void imx6ul_adc_init(struct imx6ul_tsc *tsc)
int adc_cfg;
int timeout;

+ reinit_completion(&tsc->completion);
+
adc_cfg = readl(tsc->adc_regs + REG_ADC_CFG);
adc_cfg |= ADC_12BIT_MODE | ADC_IPG_CLK;
adc_cfg |= ADC_CLK_DIV_8 | ADC_SHORT_SAMPLE_MODE;
@@ -196,17 +195,33 @@ static void imx6ul_tsc_init(struct imx6ul_tsc *tsc)
imx6ul_tsc_set(tsc);
}

+static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
+{
+ int tsc_flow;
+ int adc_cfg;
+
+ /* TSC controller enters to idle status */
+ tsc_flow = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+ tsc_flow |= TSC_DISABLE;
+ writel(tsc_flow, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
+
+ /* ADC controller enters to stop mode */
+ adc_cfg = readl(tsc->adc_regs + REG_ADC_HC0);
+ adc_cfg |= ADC_CONV_DISABLE;
+ writel(adc_cfg, tsc->adc_regs + REG_ADC_HC0);
+}
+
static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
{
struct imx6ul_tsc *tsc = (struct imx6ul_tsc *)dev_id;
int status;
int value;
int x, y;
- int xnur;
int debug_mode2;
int state_machine;
int start;
unsigned long timeout;
+ bool touch;

status = readl(tsc->tsc_regs + REG_TSC_INT_STATUS);

@@ -235,8 +250,8 @@ static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
timeout = jiffies + HZ/500;
do {
if (time_after(jiffies, timeout)) {
- xnur = 0;
- goto touch_event;
+ touch = true;
+ goto report_touch;
}
usleep_range(200, 400);
debug_mode2 = readl(tsc->tsc_regs + REG_TSC_DEBUG_MODE2);
@@ -244,14 +259,15 @@ static irqreturn_t tsc_irq_fn(int irq, void *dev_id)
} while (state_machine != DETECT_MODE);
usleep_range(200, 400);

- xnur = gpio_get_value(tsc->xnur_gpio);
-touch_event:
- if (xnur == 0) {
+ touch = gpiod_get_value_cansleep(tsc->xnur_gpio);
+report_touch:
+ if (touch) {
input_report_key(tsc->input, BTN_TOUCH, 1);
input_report_abs(tsc->input, ABS_X, x);
input_report_abs(tsc->input, ABS_Y, y);
- } else
+ } else {
input_report_key(tsc->input, BTN_TOUCH, 0);
+ }

input_sync(tsc->input);
}
@@ -261,7 +277,7 @@ touch_event:

static irqreturn_t adc_irq_fn(int irq, void *dev_id)
{
- struct imx6ul_tsc *tsc = (struct imx6ul_tsc *)dev_id;
+ struct imx6ul_tsc *tsc = dev_id;
int coco;
int value;

@@ -274,70 +290,113 @@ static irqreturn_t adc_irq_fn(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static const struct of_device_id imx6ul_tsc_match[] = {
- { .compatible = "fsl,imx6ul-tsc", },
- { /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, imx6ul_tsc_match);
+static int imx6ul_tsc_open(struct input_dev *input_dev)
+{
+ struct imx6ul_tsc *tsc = input_get_drvdata(input_dev);
+ int err;
+
+ err = clk_prepare_enable(tsc->adc_clk);
+ if (err) {
+ dev_err(tsc->dev,
+ "Could not prepare or enable the adc clock: %d\n",
+ err);
+ return err;
+ }
+
+ err = clk_prepare_enable(tsc->tsc_clk);
+ if (err) {
+ dev_err(tsc->dev,
+ "Could not prepare or enable the tsc clock: %d\n",
+ err);
+ clk_disable_unprepare(tsc->adc_clk);
+ return err;
+ }
+
+ imx6ul_tsc_init(tsc);
+
+ return 0;
+}
+
+static void imx6ul_tsc_close(struct input_dev *input_dev)
+{
+ struct imx6ul_tsc *tsc = input_get_drvdata(input_dev);
+
+ imx6ul_tsc_disable(tsc);
+
+ clk_disable_unprepare(tsc->tsc_clk);
+ clk_disable_unprepare(tsc->adc_clk);
+}

static int imx6ul_tsc_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
struct imx6ul_tsc *tsc;
+ struct input_dev *input_dev;
struct resource *tsc_mem;
struct resource *adc_mem;
- struct input_dev *input_dev;
- struct device_node *np = pdev->dev.of_node;
int err;
int tsc_irq;
int adc_irq;

tsc = devm_kzalloc(&pdev->dev, sizeof(struct imx6ul_tsc), GFP_KERNEL);
+ if (!tsc)
+ return -ENOMEM;
+
input_dev = devm_input_allocate_device(&pdev->dev);
+ if (!input_dev)
+ return -ENOMEM;

- tsc->dev = &pdev->dev;
+ input_dev->name = "iMX6UL TouchScreen Controller";
+ input_dev->id.bustype = BUS_HOST;

- tsc->input = input_dev;
- tsc->input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
- tsc->input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
- input_set_abs_params(tsc->input, ABS_X, 0, 0xFFF, 0, 0);
- input_set_abs_params(tsc->input, ABS_Y, 0, 0xFFF, 0, 0);
+ input_dev->open = imx6ul_tsc_open;
+ input_dev->close = imx6ul_tsc_close;

- tsc->input->name = "iMX6UL TouchScreen Controller";
+ input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
+ input_set_abs_params(input_dev, ABS_X, 0, 0xFFF, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, 0xFFF, 0, 0);

- tsc->xnur_gpio = of_get_named_gpio(np, "xnur-gpio", 0);
- err = gpio_request_one(tsc->xnur_gpio, GPIOF_IN, "tsc_X-");
- if (err) {
- dev_err(&pdev->dev, "failed to request GPIO tsc_X-\n");
+ input_set_drvdata(input_dev, tsc);
+
+ tsc->dev = &pdev->dev;
+ tsc->input = input_dev;
+ init_completion(&tsc->completion);
+
+ tsc->xnur_gpio = devm_gpiod_get(&pdev->dev, "xnur-gpio", GPIOD_IN);
+ if (IS_ERR(tsc->xnur_gpio)) {
+ err = PTR_ERR(tsc->xnur_gpio);
+ dev_err(&pdev->dev,
+ "failed to request GPIO tsc_X- (xnur): %d\n", err);
return err;
}

tsc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
tsc->tsc_regs = devm_ioremap_resource(&pdev->dev, tsc_mem);
if (IS_ERR(tsc->tsc_regs)) {
- dev_err(&pdev->dev, "failed to remap tsc memory\n");
err = PTR_ERR(tsc->tsc_regs);
+ dev_err(&pdev->dev, "failed to remap tsc memory: %d\n", err);
return err;
}

adc_mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
tsc->adc_regs = devm_ioremap_resource(&pdev->dev, adc_mem);
if (IS_ERR(tsc->adc_regs)) {
- dev_err(&pdev->dev, "failed to remap adc memory\n");
err = PTR_ERR(tsc->adc_regs);
+ dev_err(&pdev->dev, "failed to remap adc memory: %d\n", err);
return err;
}

tsc->tsc_clk = devm_clk_get(&pdev->dev, "tsc");
if (IS_ERR(tsc->tsc_clk)) {
- dev_err(&pdev->dev, "failed getting tsc clock\n");
err = PTR_ERR(tsc->tsc_clk);
+ dev_err(&pdev->dev, "failed getting tsc clock: %d\n", err);
return err;
}

tsc->adc_clk = devm_clk_get(&pdev->dev, "adc");
if (IS_ERR(tsc->adc_clk)) {
- dev_err(&pdev->dev, "failed getting adc clock\n");
err = PTR_ERR(tsc->adc_clk);
+ dev_err(&pdev->dev, "failed getting adc clock: %d\n", err);
return err;
}

@@ -354,111 +413,61 @@ static int imx6ul_tsc_probe(struct platform_device *pdev)
}

err = devm_request_threaded_irq(tsc->dev, tsc_irq,
- NULL, tsc_irq_fn,
- IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+ NULL, tsc_irq_fn, IRQF_ONESHOT,
dev_name(&pdev->dev), tsc);
- if (err < 0) {
+ if (err) {
dev_err(&pdev->dev,
- "failed requesting tsc irq %d\n",
- tsc_irq);
+ "failed requesting tsc irq %di: %d\n",
+ tsc_irq, err);
return err;
}

- err = devm_request_irq(tsc->dev, adc_irq,
- adc_irq_fn, 0,
+ err = devm_request_irq(tsc->dev, adc_irq, adc_irq_fn, 0,
dev_name(&pdev->dev), tsc);
- if (err < 0) {
+ if (err) {
dev_err(&pdev->dev,
- "failed requesting adc irq %d\n",
- adc_irq);
+ "failed requesting adc irq %d: %d\n",
+ adc_irq, err);
return err;
}

err = of_property_read_u32(np, "measure-delay-time",
- &tsc->measure_delay_time);
+ &tsc->measure_delay_time);
if (err)
tsc->measure_delay_time = 0xffff;

err = of_property_read_u32(np, "pre-charge-time",
- &tsc->pre_charge_time);
+ &tsc->pre_charge_time);
if (err)
tsc->pre_charge_time = 0xfff;

- init_completion(&tsc->completion);
-
- err = clk_prepare_enable(tsc->adc_clk);
+ err = input_register_device(tsc->input);
if (err) {
dev_err(&pdev->dev,
- "Could not prepare or enable the adc clock.\n");
+ "failed to register input device: %d\n", err);
return err;
}

- err = clk_prepare_enable(tsc->tsc_clk);
- if (err) {
- dev_err(&pdev->dev,
- "Could not prepare or enable the tsc clock.\n");
- goto error_tsc_clk_enable;
- }
-
- err = input_register_device(tsc->input);
- if (err < 0) {
- dev_err(&pdev->dev, "failed to register input device\n");
- err = -EIO;
- goto err_input_register;
- }
-
- imx6ul_tsc_init(tsc);
-
platform_set_drvdata(pdev, tsc);
return 0;
-
-err_input_register:
- clk_disable_unprepare(tsc->tsc_clk);
-error_tsc_clk_enable:
- clk_disable_unprepare(tsc->adc_clk);
-
- return err;
-}
-
-static void imx6ul_tsc_disable(struct imx6ul_tsc *tsc)
-{
- int tsc_flow;
- int adc_cfg;
-
- /* TSC controller enters to idle status */
- tsc_flow = readl(tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
- tsc_flow |= TSC_DISABLE;
- writel(tsc_flow, tsc->tsc_regs + REG_TSC_FLOW_CONTROL);
-
- /* ADC controller enters to stop mode */
- adc_cfg = readl(tsc->adc_regs + REG_ADC_HC0);
- adc_cfg |= ADC_CONV_DISABLE;
- writel(adc_cfg, tsc->adc_regs + REG_ADC_HC0);
-}
-
-static int imx6ul_tsc_remove(struct platform_device *pdev)
-{
- struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
-
- imx6ul_tsc_disable(tsc);
-
- clk_disable_unprepare(tsc->tsc_clk);
- clk_disable_unprepare(tsc->adc_clk);
- input_unregister_device(tsc->input);
- kfree(tsc);
-
- return 0;
}

static int __maybe_unused imx6ul_tsc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
+ struct input_dev *input_dev = tsc->input;

- imx6ul_tsc_disable(tsc);
+ mutex_lock(&input_dev->mutex);

- clk_disable_unprepare(tsc->tsc_clk);
- clk_disable_unprepare(tsc->adc_clk);
+ if (input_dev->users) {
+ imx6ul_tsc_disable(tsc);
+
+ clk_disable_unprepare(tsc->tsc_clk);
+ clk_disable_unprepare(tsc->adc_clk);
+ }
+
+ mutex_unlock(&input_dev->mutex);

return 0;
}
@@ -467,35 +476,46 @@ static int __maybe_unused imx6ul_tsc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct imx6ul_tsc *tsc = platform_get_drvdata(pdev);
- int err;
+ struct input_dev *input_dev = tsc->input;
+ int retval = 0;

- err = clk_prepare_enable(tsc->adc_clk);
- if (err)
- return err;
+ mutex_lock(&input_dev->mutex);

- err = clk_prepare_enable(tsc->tsc_clk);
- if (err) {
- clk_disable_unprepare(tsc->adc_clk);
- return err;
+ if (input_dev->users) {
+ retval = clk_prepare_enable(tsc->adc_clk);
+ if (retval)
+ goto out;
+
+ retval = clk_prepare_enable(tsc->tsc_clk);
+ if (retval) {
+ clk_disable_unprepare(tsc->adc_clk);
+ goto out;
+ }
+
+ imx6ul_tsc_init(tsc);
}

- imx6ul_tsc_init(tsc);
- return 0;
+out:
+ mutex_unlock(&input_dev->mutex);
+ return retval;
}

static SIMPLE_DEV_PM_OPS(imx6ul_tsc_pm_ops,
- imx6ul_tsc_suspend,
- imx6ul_tsc_resume);
+ imx6ul_tsc_suspend, imx6ul_tsc_resume);
+
+static const struct of_device_id imx6ul_tsc_match[] = {
+ { .compatible = "fsl,imx6ul-tsc", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx6ul_tsc_match);

static struct platform_driver imx6ul_tsc_driver = {
.driver = {
.name = "imx6ul-tsc",
- .owner = THIS_MODULE,
.of_match_table = imx6ul_tsc_match,
.pm = &imx6ul_tsc_pm_ops,
},
.probe = imx6ul_tsc_probe,
- .remove = imx6ul_tsc_remove,
};
module_platform_driver(imx6ul_tsc_driver);

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