diff options
Diffstat (limited to 'drivers/input/touchscreen/wm831x-ts.c')
| -rw-r--r-- | drivers/input/touchscreen/wm831x-ts.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/wm831x-ts.c b/drivers/input/touchscreen/wm831x-ts.c new file mode 100644 index 000000000..319f57fb9 --- /dev/null +++ b/drivers/input/touchscreen/wm831x-ts.c @@ -0,0 +1,400 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Touchscreen driver for WM831x PMICs + * + * Copyright 2011 Wolfson Microelectronics plc. + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/pm.h> +#include <linux/input.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mfd/wm831x/core.h> +#include <linux/mfd/wm831x/irq.h> +#include <linux/mfd/wm831x/pdata.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> + +/* + * R16424 (0x4028) - Touch Control 1 + */ +#define WM831X_TCH_ENA 0x8000 /* TCH_ENA */ +#define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */ +#define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */ +#define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */ +#define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */ +#define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */ +#define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */ +#define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */ +#define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */ +#define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */ +#define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */ +#define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */ + +/* + * R16425 (0x4029) - Touch Control 2 + */ +#define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */ +#define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */ +#define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */ +#define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */ +#define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */ +#define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */ +#define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */ + +/* + * R16426-8 (0x402A-C) - Touch Data X/Y/X + */ +#define WM831X_TCH_PD 0x8000 /* TCH_PD1 */ +#define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */ +#define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */ +#define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */ + +struct wm831x_ts { + struct input_dev *input_dev; + struct wm831x *wm831x; + unsigned int data_irq; + unsigned int pd_irq; + bool pressure; + bool pen_down; + struct work_struct pd_data_work; +}; + +static void wm831x_pd_data_work(struct work_struct *work) +{ + struct wm831x_ts *wm831x_ts = + container_of(work, struct wm831x_ts, pd_data_work); + + if (wm831x_ts->pen_down) { + enable_irq(wm831x_ts->data_irq); + dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n"); + } else { + enable_irq(wm831x_ts->pd_irq); + dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n"); + } +} + +static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data) +{ + struct wm831x_ts *wm831x_ts = irq_data; + struct wm831x *wm831x = wm831x_ts->wm831x; + static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE }; + u16 data[3]; + int count; + int i, ret; + + if (wm831x_ts->pressure) + count = 3; + else + count = 2; + + wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, + WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); + + ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, + data); + if (ret != 0) { + dev_err(wm831x->dev, "Failed to read touch data: %d\n", + ret); + return IRQ_NONE; + } + + /* + * We get a pen down reading on every reading, report pen up if any + * individual reading does so. + */ + wm831x_ts->pen_down = true; + for (i = 0; i < count; i++) { + if (!(data[i] & WM831X_TCH_PD)) { + wm831x_ts->pen_down = false; + continue; + } + input_report_abs(wm831x_ts->input_dev, data_types[i], + data[i] & WM831X_TCH_DATA_MASK); + } + + if (!wm831x_ts->pen_down) { + /* Switch from data to pen down */ + dev_dbg(wm831x->dev, "IRQ DATA->PD\n"); + + disable_irq_nosync(wm831x_ts->data_irq); + + /* Don't need data any more */ + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | + WM831X_TCH_Z_ENA, 0); + + /* Flush any final samples that arrived while reading */ + wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, + WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); + + wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data); + + if (wm831x_ts->pressure) + input_report_abs(wm831x_ts->input_dev, + ABS_PRESSURE, 0); + + input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0); + + schedule_work(&wm831x_ts->pd_data_work); + } else { + input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1); + } + + input_sync(wm831x_ts->input_dev); + + return IRQ_HANDLED; +} + +static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data) +{ + struct wm831x_ts *wm831x_ts = irq_data; + struct wm831x *wm831x = wm831x_ts->wm831x; + int ena = 0; + + if (wm831x_ts->pen_down) + return IRQ_HANDLED; + + disable_irq_nosync(wm831x_ts->pd_irq); + + /* Start collecting data */ + if (wm831x_ts->pressure) + ena |= WM831X_TCH_Z_ENA; + + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, + WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena); + + wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, + WM831X_TCHPD_EINT, WM831X_TCHPD_EINT); + + wm831x_ts->pen_down = true; + + /* Switch from pen down to data */ + dev_dbg(wm831x->dev, "IRQ PD->DATA\n"); + schedule_work(&wm831x_ts->pd_data_work); + + return IRQ_HANDLED; +} + +static int wm831x_ts_input_open(struct input_dev *idev) +{ + struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); + struct wm831x *wm831x = wm831x_ts->wm831x; + + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_ENA | WM831X_TCH_CVT_ENA | + WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | + WM831X_TCH_Z_ENA, WM831X_TCH_ENA); + + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA); + + return 0; +} + +static void wm831x_ts_input_close(struct input_dev *idev) +{ + struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); + struct wm831x *wm831x = wm831x_ts->wm831x; + + /* Shut the controller down, disabling all other functionality too */ + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_ENA | WM831X_TCH_X_ENA | + WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0); + + /* Make sure any pending IRQs are done, the above will prevent + * new ones firing. + */ + synchronize_irq(wm831x_ts->data_irq); + synchronize_irq(wm831x_ts->pd_irq); + + /* Make sure the IRQ completion work is quiesced */ + flush_work(&wm831x_ts->pd_data_work); + + /* If we ended up with the pen down then make sure we revert back + * to pen detection state for the next time we start up. + */ + if (wm831x_ts->pen_down) { + disable_irq(wm831x_ts->data_irq); + enable_irq(wm831x_ts->pd_irq); + wm831x_ts->pen_down = false; + } +} + +static int wm831x_ts_probe(struct platform_device *pdev) +{ + struct wm831x_ts *wm831x_ts; + struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); + struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent); + struct wm831x_touch_pdata *pdata = NULL; + struct input_dev *input_dev; + int error, irqf; + + if (core_pdata) + pdata = core_pdata->touch; + + wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts), + GFP_KERNEL); + input_dev = devm_input_allocate_device(&pdev->dev); + if (!wm831x_ts || !input_dev) { + error = -ENOMEM; + goto err_alloc; + } + + wm831x_ts->wm831x = wm831x; + wm831x_ts->input_dev = input_dev; + INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work); + + /* + * If we have a direct IRQ use it, otherwise use the interrupt + * from the WM831x IRQ controller. + */ + wm831x_ts->data_irq = wm831x_irq(wm831x, + platform_get_irq_byname(pdev, + "TCHDATA")); + if (pdata && pdata->data_irq) + wm831x_ts->data_irq = pdata->data_irq; + + wm831x_ts->pd_irq = wm831x_irq(wm831x, + platform_get_irq_byname(pdev, "TCHPD")); + if (pdata && pdata->pd_irq) + wm831x_ts->pd_irq = pdata->pd_irq; + + if (pdata) + wm831x_ts->pressure = pdata->pressure; + else + wm831x_ts->pressure = true; + + /* Five wire touchscreens can't report pressure */ + if (pdata && pdata->fivewire) { + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, + WM831X_TCH_5WIRE, WM831X_TCH_5WIRE); + + /* Pressure measurements are not possible for five wire mode */ + WARN_ON(pdata->pressure && pdata->fivewire); + wm831x_ts->pressure = false; + } else { + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, + WM831X_TCH_5WIRE, 0); + } + + if (pdata) { + switch (pdata->isel) { + default: + dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n", + pdata->isel); + fallthrough; + case 200: + case 0: + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, + WM831X_TCH_ISEL, 0); + break; + case 400: + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, + WM831X_TCH_ISEL, WM831X_TCH_ISEL); + break; + } + } + + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, + WM831X_TCH_PDONLY, 0); + + /* Default to 96 samples/sec */ + wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, + WM831X_TCH_RATE_MASK, 6); + + if (pdata && pdata->data_irqf) + irqf = pdata->data_irqf; + else + irqf = IRQF_TRIGGER_HIGH; + + error = request_threaded_irq(wm831x_ts->data_irq, + NULL, wm831x_ts_data_irq, + irqf | IRQF_ONESHOT | IRQF_NO_AUTOEN, + "Touchscreen data", wm831x_ts); + if (error) { + dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n", + wm831x_ts->data_irq, error); + goto err_alloc; + } + + if (pdata && pdata->pd_irqf) + irqf = pdata->pd_irqf; + else + irqf = IRQF_TRIGGER_HIGH; + + error = request_threaded_irq(wm831x_ts->pd_irq, + NULL, wm831x_ts_pen_down_irq, + irqf | IRQF_ONESHOT, + "Touchscreen pen down", wm831x_ts); + if (error) { + dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n", + wm831x_ts->pd_irq, error); + goto err_data_irq; + } + + /* set up touch configuration */ + input_dev->name = "WM831x touchscreen"; + input_dev->phys = "wm831x"; + input_dev->open = wm831x_ts_input_open; + input_dev->close = wm831x_ts_input_close; + + __set_bit(EV_ABS, input_dev->evbit); + __set_bit(EV_KEY, input_dev->evbit); + __set_bit(BTN_TOUCH, input_dev->keybit); + + input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0); + input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0); + if (wm831x_ts->pressure) + input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0); + + input_set_drvdata(input_dev, wm831x_ts); + input_dev->dev.parent = &pdev->dev; + + error = input_register_device(input_dev); + if (error) + goto err_pd_irq; + + platform_set_drvdata(pdev, wm831x_ts); + return 0; + +err_pd_irq: + free_irq(wm831x_ts->pd_irq, wm831x_ts); +err_data_irq: + free_irq(wm831x_ts->data_irq, wm831x_ts); +err_alloc: + + return error; +} + +static int wm831x_ts_remove(struct platform_device *pdev) +{ + struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev); + + free_irq(wm831x_ts->pd_irq, wm831x_ts); + free_irq(wm831x_ts->data_irq, wm831x_ts); + + return 0; +} + +static struct platform_driver wm831x_ts_driver = { + .driver = { + .name = "wm831x-touch", + }, + .probe = wm831x_ts_probe, + .remove = wm831x_ts_remove, +}; +module_platform_driver(wm831x_ts_driver); + +/* Module information */ +MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); +MODULE_DESCRIPTION("WM831x PMIC touchscreen driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:wm831x-touch"); |