16decea7cSHans de Goede /* 26decea7cSHans de Goede * Allwinner sunxi resistive touchscreen controller driver 36decea7cSHans de Goede * 46decea7cSHans de Goede * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com> 56decea7cSHans de Goede * 66decea7cSHans de Goede * This program is free software; you can redistribute it and/or modify 76decea7cSHans de Goede * it under the terms of the GNU General Public License as published by 86decea7cSHans de Goede * the Free Software Foundation; either version 2 of the License, or 96decea7cSHans de Goede * (at your option) any later version. 106decea7cSHans de Goede * 116decea7cSHans de Goede * This program is distributed in the hope that it will be useful, 126decea7cSHans de Goede * but WITHOUT ANY WARRANTY; without even the implied warranty of 136decea7cSHans de Goede * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 146decea7cSHans de Goede * GNU General Public License for more details. 156decea7cSHans de Goede */ 166decea7cSHans de Goede 176decea7cSHans de Goede /* 186decea7cSHans de Goede * The sun4i-ts controller is capable of detecting a second touch, but when a 196decea7cSHans de Goede * second touch is present then the accuracy becomes so bad the reported touch 206decea7cSHans de Goede * location is not useable. 216decea7cSHans de Goede * 226decea7cSHans de Goede * The original android driver contains some complicated heuristics using the 236decea7cSHans de Goede * aprox. distance between the 2 touches to see if the user is making a pinch 246decea7cSHans de Goede * open / close movement, and then reports emulated multi-touch events around 256decea7cSHans de Goede * the last touch coordinate (as the dual-touch coordinates are worthless). 266decea7cSHans de Goede * 276decea7cSHans de Goede * These kinds of heuristics are just asking for trouble (and don't belong 286decea7cSHans de Goede * in the kernel). So this driver offers straight forward, reliable single 296decea7cSHans de Goede * touch functionality only. 306decea7cSHans de Goede */ 316decea7cSHans de Goede 326decea7cSHans de Goede #include <linux/err.h> 336decea7cSHans de Goede #include <linux/init.h> 346decea7cSHans de Goede #include <linux/input.h> 356decea7cSHans de Goede #include <linux/interrupt.h> 366decea7cSHans de Goede #include <linux/io.h> 376decea7cSHans de Goede #include <linux/module.h> 386decea7cSHans de Goede #include <linux/of_platform.h> 396decea7cSHans de Goede #include <linux/platform_device.h> 406decea7cSHans de Goede #include <linux/slab.h> 416decea7cSHans de Goede 426decea7cSHans de Goede #define TP_CTRL0 0x00 436decea7cSHans de Goede #define TP_CTRL1 0x04 446decea7cSHans de Goede #define TP_CTRL2 0x08 456decea7cSHans de Goede #define TP_CTRL3 0x0c 466decea7cSHans de Goede #define TP_INT_FIFOC 0x10 476decea7cSHans de Goede #define TP_INT_FIFOS 0x14 486decea7cSHans de Goede #define TP_TPR 0x18 496decea7cSHans de Goede #define TP_CDAT 0x1c 506decea7cSHans de Goede #define TEMP_DATA 0x20 516decea7cSHans de Goede #define TP_DATA 0x24 526decea7cSHans de Goede 536decea7cSHans de Goede /* TP_CTRL0 bits */ 546decea7cSHans de Goede #define ADC_FIRST_DLY(x) ((x) << 24) /* 8 bits */ 556decea7cSHans de Goede #define ADC_FIRST_DLY_MODE(x) ((x) << 23) 566decea7cSHans de Goede #define ADC_CLK_SEL(x) ((x) << 22) 576decea7cSHans de Goede #define ADC_CLK_DIV(x) ((x) << 20) /* 3 bits */ 586decea7cSHans de Goede #define FS_DIV(x) ((x) << 16) /* 4 bits */ 596decea7cSHans de Goede #define T_ACQ(x) ((x) << 0) /* 16 bits */ 606decea7cSHans de Goede 616decea7cSHans de Goede /* TP_CTRL1 bits */ 626decea7cSHans de Goede #define STYLUS_UP_DEBOUN(x) ((x) << 12) /* 8 bits */ 636decea7cSHans de Goede #define STYLUS_UP_DEBOUN_EN(x) ((x) << 9) 646decea7cSHans de Goede #define TOUCH_PAN_CALI_EN(x) ((x) << 6) 656decea7cSHans de Goede #define TP_DUAL_EN(x) ((x) << 5) 666decea7cSHans de Goede #define TP_MODE_EN(x) ((x) << 4) 676decea7cSHans de Goede #define TP_ADC_SELECT(x) ((x) << 3) 686decea7cSHans de Goede #define ADC_CHAN_SELECT(x) ((x) << 0) /* 3 bits */ 696decea7cSHans de Goede 706decea7cSHans de Goede /* TP_CTRL2 bits */ 716decea7cSHans de Goede #define TP_SENSITIVE_ADJUST(x) ((x) << 28) /* 4 bits */ 726decea7cSHans de Goede #define TP_MODE_SELECT(x) ((x) << 26) /* 2 bits */ 736decea7cSHans de Goede #define PRE_MEA_EN(x) ((x) << 24) 746decea7cSHans de Goede #define PRE_MEA_THRE_CNT(x) ((x) << 0) /* 24 bits */ 756decea7cSHans de Goede 766decea7cSHans de Goede /* TP_CTRL3 bits */ 776decea7cSHans de Goede #define FILTER_EN(x) ((x) << 2) 786decea7cSHans de Goede #define FILTER_TYPE(x) ((x) << 0) /* 2 bits */ 796decea7cSHans de Goede 806decea7cSHans de Goede /* TP_INT_FIFOC irq and fifo mask / control bits */ 816decea7cSHans de Goede #define TEMP_IRQ_EN(x) ((x) << 18) 826decea7cSHans de Goede #define OVERRUN_IRQ_EN(x) ((x) << 17) 836decea7cSHans de Goede #define DATA_IRQ_EN(x) ((x) << 16) 846decea7cSHans de Goede #define TP_DATA_XY_CHANGE(x) ((x) << 13) 856decea7cSHans de Goede #define FIFO_TRIG(x) ((x) << 8) /* 5 bits */ 866decea7cSHans de Goede #define DATA_DRQ_EN(x) ((x) << 7) 876decea7cSHans de Goede #define FIFO_FLUSH(x) ((x) << 4) 886decea7cSHans de Goede #define TP_UP_IRQ_EN(x) ((x) << 1) 896decea7cSHans de Goede #define TP_DOWN_IRQ_EN(x) ((x) << 0) 906decea7cSHans de Goede 916decea7cSHans de Goede /* TP_INT_FIFOS irq and fifo status bits */ 926decea7cSHans de Goede #define TEMP_DATA_PENDING BIT(18) 936decea7cSHans de Goede #define FIFO_OVERRUN_PENDING BIT(17) 946decea7cSHans de Goede #define FIFO_DATA_PENDING BIT(16) 956decea7cSHans de Goede #define TP_IDLE_FLG BIT(2) 966decea7cSHans de Goede #define TP_UP_PENDING BIT(1) 976decea7cSHans de Goede #define TP_DOWN_PENDING BIT(0) 986decea7cSHans de Goede 996decea7cSHans de Goede /* TP_TPR bits */ 1006decea7cSHans de Goede #define TEMP_ENABLE(x) ((x) << 16) 1016decea7cSHans de Goede #define TEMP_PERIOD(x) ((x) << 0) /* t = x * 256 * 16 / clkin */ 1026decea7cSHans de Goede 1036decea7cSHans de Goede struct sun4i_ts_data { 1046decea7cSHans de Goede struct device *dev; 1056decea7cSHans de Goede struct input_dev *input; 1066decea7cSHans de Goede void __iomem *base; 1076decea7cSHans de Goede unsigned int irq; 1086decea7cSHans de Goede bool ignore_fifo_data; 1096decea7cSHans de Goede }; 1106decea7cSHans de Goede 1116decea7cSHans de Goede static irqreturn_t sun4i_ts_irq(int irq, void *dev_id) 1126decea7cSHans de Goede { 1136decea7cSHans de Goede struct sun4i_ts_data *ts = dev_id; 1146decea7cSHans de Goede u32 reg_val, x, y; 1156decea7cSHans de Goede 1166decea7cSHans de Goede reg_val = readl(ts->base + TP_INT_FIFOS); 1176decea7cSHans de Goede 1186decea7cSHans de Goede if (reg_val & FIFO_DATA_PENDING) { 1196decea7cSHans de Goede x = readl(ts->base + TP_DATA); 1206decea7cSHans de Goede y = readl(ts->base + TP_DATA); 1216decea7cSHans de Goede /* The 1st location reported after an up event is unreliable */ 1226decea7cSHans de Goede if (!ts->ignore_fifo_data) { 1236decea7cSHans de Goede input_report_abs(ts->input, ABS_X, x); 1246decea7cSHans de Goede input_report_abs(ts->input, ABS_Y, y); 1256decea7cSHans de Goede /* 1266decea7cSHans de Goede * The hardware has a separate down status bit, but 1276decea7cSHans de Goede * that gets set before we get the first location, 1286decea7cSHans de Goede * resulting in reporting a click on the old location. 1296decea7cSHans de Goede */ 1306decea7cSHans de Goede input_report_key(ts->input, BTN_TOUCH, 1); 1316decea7cSHans de Goede input_sync(ts->input); 1326decea7cSHans de Goede } else { 1336decea7cSHans de Goede ts->ignore_fifo_data = false; 1346decea7cSHans de Goede } 1356decea7cSHans de Goede } 1366decea7cSHans de Goede 1376decea7cSHans de Goede if (reg_val & TP_UP_PENDING) { 1386decea7cSHans de Goede ts->ignore_fifo_data = true; 1396decea7cSHans de Goede input_report_key(ts->input, BTN_TOUCH, 0); 1406decea7cSHans de Goede input_sync(ts->input); 1416decea7cSHans de Goede } 1426decea7cSHans de Goede 1436decea7cSHans de Goede writel(reg_val, ts->base + TP_INT_FIFOS); 1446decea7cSHans de Goede 1456decea7cSHans de Goede return IRQ_HANDLED; 1466decea7cSHans de Goede } 1476decea7cSHans de Goede 1486decea7cSHans de Goede static int sun4i_ts_open(struct input_dev *dev) 1496decea7cSHans de Goede { 1506decea7cSHans de Goede struct sun4i_ts_data *ts = input_get_drvdata(dev); 1516decea7cSHans de Goede 1526decea7cSHans de Goede /* Flush, set trig level to 1, enable data and up irqs */ 1536decea7cSHans de Goede writel(DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) | TP_UP_IRQ_EN(1), 1546decea7cSHans de Goede ts->base + TP_INT_FIFOC); 1556decea7cSHans de Goede 1566decea7cSHans de Goede return 0; 1576decea7cSHans de Goede } 1586decea7cSHans de Goede 1596decea7cSHans de Goede static void sun4i_ts_close(struct input_dev *dev) 1606decea7cSHans de Goede { 1616decea7cSHans de Goede struct sun4i_ts_data *ts = input_get_drvdata(dev); 1626decea7cSHans de Goede 1636decea7cSHans de Goede /* Deactivate all IRQs */ 1646decea7cSHans de Goede writel(0, ts->base + TP_INT_FIFOC); 1656decea7cSHans de Goede } 1666decea7cSHans de Goede 1676decea7cSHans de Goede static int sun4i_ts_probe(struct platform_device *pdev) 1686decea7cSHans de Goede { 1696decea7cSHans de Goede struct sun4i_ts_data *ts; 1706decea7cSHans de Goede struct device *dev = &pdev->dev; 1716decea7cSHans de Goede int error; 1726decea7cSHans de Goede 1736decea7cSHans de Goede ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL); 1746decea7cSHans de Goede if (!ts) 1756decea7cSHans de Goede return -ENOMEM; 1766decea7cSHans de Goede 1776decea7cSHans de Goede ts->dev = dev; 1786decea7cSHans de Goede ts->ignore_fifo_data = true; 1796decea7cSHans de Goede 1806decea7cSHans de Goede ts->input = devm_input_allocate_device(dev); 1816decea7cSHans de Goede if (!ts->input) 1826decea7cSHans de Goede return -ENOMEM; 1836decea7cSHans de Goede 1846decea7cSHans de Goede ts->input->name = pdev->name; 1856decea7cSHans de Goede ts->input->phys = "sun4i_ts/input0"; 1866decea7cSHans de Goede ts->input->open = sun4i_ts_open; 1876decea7cSHans de Goede ts->input->close = sun4i_ts_close; 1886decea7cSHans de Goede ts->input->id.bustype = BUS_HOST; 1896decea7cSHans de Goede ts->input->id.vendor = 0x0001; 1906decea7cSHans de Goede ts->input->id.product = 0x0001; 1916decea7cSHans de Goede ts->input->id.version = 0x0100; 1926decea7cSHans de Goede ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS); 1936decea7cSHans de Goede __set_bit(BTN_TOUCH, ts->input->keybit); 1946decea7cSHans de Goede input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0); 1956decea7cSHans de Goede input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0); 1966decea7cSHans de Goede input_set_drvdata(ts->input, ts); 1976decea7cSHans de Goede 1986decea7cSHans de Goede ts->base = devm_ioremap_resource(dev, 1996decea7cSHans de Goede platform_get_resource(pdev, IORESOURCE_MEM, 0)); 2006decea7cSHans de Goede if (IS_ERR(ts->base)) 2016decea7cSHans de Goede return PTR_ERR(ts->base); 2026decea7cSHans de Goede 2036decea7cSHans de Goede ts->irq = platform_get_irq(pdev, 0); 2046decea7cSHans de Goede error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts); 2056decea7cSHans de Goede if (error) 2066decea7cSHans de Goede return error; 2076decea7cSHans de Goede 2086decea7cSHans de Goede /* 2096decea7cSHans de Goede * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192, 2106decea7cSHans de Goede * t_acq = clkin / (16 * 64) 2116decea7cSHans de Goede */ 2126decea7cSHans de Goede writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63), 2136decea7cSHans de Goede ts->base + TP_CTRL0); 2146decea7cSHans de Goede 2156decea7cSHans de Goede /* 2166decea7cSHans de Goede * sensitive_adjust = 15 : max, which is not all that sensitive, 2176decea7cSHans de Goede * tp_mode = 0 : only x and y coordinates, as we don't use dual touch 2186decea7cSHans de Goede */ 2196decea7cSHans de Goede writel(TP_SENSITIVE_ADJUST(15) | TP_MODE_SELECT(0), 2206decea7cSHans de Goede ts->base + TP_CTRL2); 2216decea7cSHans de Goede 2226decea7cSHans de Goede /* Enable median filter, type 1 : 5/3 */ 2236decea7cSHans de Goede writel(FILTER_EN(1) | FILTER_TYPE(1), ts->base + TP_CTRL3); 2246decea7cSHans de Goede 2256decea7cSHans de Goede /* Enable temperature measurement, period 1953 (2 seconds) */ 2266decea7cSHans de Goede writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR); 2276decea7cSHans de Goede 2286decea7cSHans de Goede /* 2296decea7cSHans de Goede * Set stylus up debounce to aprox 10 ms, enable debounce, and 2306decea7cSHans de Goede * finally enable tp mode. 2316decea7cSHans de Goede */ 2326decea7cSHans de Goede writel(STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1) | TP_MODE_EN(1), 2336decea7cSHans de Goede ts->base + TP_CTRL1); 2346decea7cSHans de Goede 2356decea7cSHans de Goede error = input_register_device(ts->input); 2366decea7cSHans de Goede if (error) 2376decea7cSHans de Goede return error; 2386decea7cSHans de Goede 2396decea7cSHans de Goede platform_set_drvdata(pdev, ts); 2406decea7cSHans de Goede return 0; 2416decea7cSHans de Goede } 2426decea7cSHans de Goede 2436decea7cSHans de Goede static const struct of_device_id sun4i_ts_of_match[] = { 2446decea7cSHans de Goede { .compatible = "allwinner,sun4i-a10-ts", }, 2456decea7cSHans de Goede { /* sentinel */ } 2466decea7cSHans de Goede }; 2476decea7cSHans de Goede MODULE_DEVICE_TABLE(of, sun4i_ts_of_match); 2486decea7cSHans de Goede 2496decea7cSHans de Goede static struct platform_driver sun4i_ts_driver = { 2506decea7cSHans de Goede .driver = { 2516decea7cSHans de Goede .owner = THIS_MODULE, 2526decea7cSHans de Goede .name = "sun4i-ts", 2536decea7cSHans de Goede .of_match_table = of_match_ptr(sun4i_ts_of_match), 2546decea7cSHans de Goede }, 2556decea7cSHans de Goede .probe = sun4i_ts_probe, 2566decea7cSHans de Goede }; 2576decea7cSHans de Goede 2586decea7cSHans de Goede module_platform_driver(sun4i_ts_driver); 2596decea7cSHans de Goede 2606decea7cSHans de Goede MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver"); 2616decea7cSHans de Goede MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 2626decea7cSHans de Goede MODULE_LICENSE("GPL"); 263