/* * Touchscreen driver for WM831x PMICs * * Copyright 2011 Wolfson Microelectronics plc. * Author: Mark Brown * * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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_sync(&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 __devinit 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 = kzalloc(sizeof(struct wm831x_ts), GFP_KERNEL); input_dev = input_allocate_device(); 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. */ if (pdata && pdata->data_irq) wm831x_ts->data_irq = pdata->data_irq; else wm831x_ts->data_irq = platform_get_irq_byname(pdev, "TCHDATA"); if (pdata && pdata->pd_irq) wm831x_ts->pd_irq = pdata->pd_irq; else wm831x_ts->pd_irq = platform_get_irq_byname(pdev, "TCHPD"); 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); /* Fall through */ 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, "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; } disable_irq(wm831x_ts->data_irq); 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: input_free_device(input_dev); kfree(wm831x_ts); return error; } static __devexit 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); input_unregister_device(wm831x_ts->input_dev); kfree(wm831x_ts); platform_set_drvdata(pdev, NULL); return 0; } static struct platform_driver wm831x_ts_driver = { .driver = { .name = "wm831x-touch", .owner = THIS_MODULE, }, .probe = wm831x_ts_probe, .remove = __devexit_p(wm831x_ts_remove), }; static int __init wm831x_ts_init(void) { return platform_driver_register(&wm831x_ts_driver); } module_init(wm831x_ts_init); static void __exit wm831x_ts_exit(void) { platform_driver_unregister(&wm831x_ts_driver); } module_exit(wm831x_ts_exit); /* Module information */ MODULE_AUTHOR("Mark Brown "); MODULE_DESCRIPTION("WM831x PMIC touchscreen driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:wm831x-touch");