From: Damien Riegel Date: Wed, 16 Dec 2015 19:49:14 +0000 (-0800) Subject: Input: add touchscreen support for TS-4800 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=40e3be3933aee185fd6ab1ec87dfaf3502d9f5b3;p=linux-beck.git Input: add touchscreen support for TS-4800 On this board, the touchscreen, an ads7843, is not handled directly by Linux but by a companion FPGA. This FPGA is memory-mapped and the IP design is very similar to the mk712. This commit adds the support for this IP. Signed-off-by: Damien Riegel Acked-by: Rob Herring Signed-off-by: Dmitry Torokhov --- diff --git a/Documentation/devicetree/bindings/input/touchscreen/ts4800-ts.txt b/Documentation/devicetree/bindings/input/touchscreen/ts4800-ts.txt new file mode 100644 index 000000000000..4c1c092c276b --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/ts4800-ts.txt @@ -0,0 +1,11 @@ +* TS-4800 Touchscreen bindings + +Required properties: +- compatible: must be "technologic,ts4800-ts" +- reg: physical base address of the controller and length of memory mapped + region. +- syscon: phandle / integers array that points to the syscon node which + describes the FPGA's syscon registers. + - phandle to FPGA's syscon + - offset to the touchscreen register + - offset to the touchscreen enable bit diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 9bcb718668b2..f986e8b44b5f 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -937,6 +937,22 @@ config TOUCHSCREEN_TOUCHIT213 To compile this driver as a module, choose M here: the module will be called touchit213. +config TOUCHSCREEN_TS4800 + tristate "TS-4800 touchscreen" + depends on HAS_IOMEM && OF + select MFD_SYSCON + select INPUT_POLLDEV + help + Say Y here if you have a touchscreen on a TS-4800 board. + + On TS-4800, the touchscreen is not handled directly by Linux but by + a companion FPGA. + + If unsure, say N. + + To compile this driver as a module, choose M here: the + module will be called ts4800_ts. + config TOUCHSCREEN_TSC_SERIO tristate "TSC-10/25/40 serial touchscreen support" select SERIO diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 001357c3f73f..968ff12e3132 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -69,6 +69,7 @@ obj-$(CONFIG_TOUCHSCREEN_TI_AM335X_TSC) += ti_am335x_tsc.o obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213) += touchit213.o obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT) += touchright.o obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o +obj-$(CONFIG_TOUCHSCREEN_TS4800) += ts4800-ts.o obj-$(CONFIG_TOUCHSCREEN_TSC_SERIO) += tsc40.o obj-$(CONFIG_TOUCHSCREEN_TSC200X_CORE) += tsc200x-core.o obj-$(CONFIG_TOUCHSCREEN_TSC2004) += tsc2004.o diff --git a/drivers/input/touchscreen/ts4800-ts.c b/drivers/input/touchscreen/ts4800-ts.c new file mode 100644 index 000000000000..3c3dd78303be --- /dev/null +++ b/drivers/input/touchscreen/ts4800-ts.c @@ -0,0 +1,216 @@ +/* + * Touchscreen driver for the TS-4800 board + * + * Copyright (c) 2015 - Savoir-faire Linux + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* polling interval in ms */ +#define POLL_INTERVAL 3 + +#define DEBOUNCE_COUNT 1 + +/* sensor values are 12-bit wide */ +#define MAX_12BIT ((1 << 12) - 1) + +#define PENDOWN_MASK 0x1 + +#define X_OFFSET 0x0 +#define Y_OFFSET 0x2 + +struct ts4800_ts { + struct input_polled_dev *poll_dev; + struct device *dev; + char phys[32]; + + void __iomem *base; + struct regmap *regmap; + unsigned int reg; + unsigned int bit; + + bool pendown; + int debounce; +}; + +static void ts4800_ts_open(struct input_polled_dev *dev) +{ + struct ts4800_ts *ts = dev->private; + int ret; + + ts->pendown = false; + ts->debounce = DEBOUNCE_COUNT; + + ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, ts->bit); + if (ret) + dev_warn(ts->dev, "Failed to enable touchscreen\n"); +} + +static void ts4800_ts_close(struct input_polled_dev *dev) +{ + struct ts4800_ts *ts = dev->private; + int ret; + + ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, 0); + if (ret) + dev_warn(ts->dev, "Failed to disable touchscreen\n"); + +} + +static void ts4800_ts_poll(struct input_polled_dev *dev) +{ + struct input_dev *input_dev = dev->input; + struct ts4800_ts *ts = dev->private; + u16 last_x = readw(ts->base + X_OFFSET); + u16 last_y = readw(ts->base + Y_OFFSET); + bool pendown = last_x & PENDOWN_MASK; + + if (pendown) { + if (ts->debounce) { + ts->debounce--; + return; + } + + if (!ts->pendown) { + input_report_key(input_dev, BTN_TOUCH, 1); + ts->pendown = true; + } + + last_x = ((~last_x) >> 4) & MAX_12BIT; + last_y = ((~last_y) >> 4) & MAX_12BIT; + + input_report_abs(input_dev, ABS_X, last_x); + input_report_abs(input_dev, ABS_Y, last_y); + input_sync(input_dev); + } else if (ts->pendown) { + ts->pendown = false; + ts->debounce = DEBOUNCE_COUNT; + input_report_key(input_dev, BTN_TOUCH, 0); + input_sync(input_dev); + } +} + +static int ts4800_parse_dt(struct platform_device *pdev, + struct ts4800_ts *ts) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *syscon_np; + u32 reg, bit; + int error; + + syscon_np = of_parse_phandle(np, "syscon", 0); + if (!syscon_np) { + dev_err(dev, "no syscon property\n"); + return -ENODEV; + } + + error = of_property_read_u32_index(np, "syscon", 1, ®); + if (error < 0) { + dev_err(dev, "no offset in syscon\n"); + return error; + } + + ts->reg = reg; + + error = of_property_read_u32_index(np, "syscon", 2, &bit); + if (error < 0) { + dev_err(dev, "no bit in syscon\n"); + return error; + } + + ts->bit = BIT(bit); + + ts->regmap = syscon_node_to_regmap(syscon_np); + if (IS_ERR(ts->regmap)) { + dev_err(dev, "cannot get parent's regmap\n"); + return PTR_ERR(ts->regmap); + } + + return 0; +} + +static int ts4800_ts_probe(struct platform_device *pdev) +{ + struct input_polled_dev *poll_dev; + struct ts4800_ts *ts; + struct resource *res; + int error; + + ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + error = ts4800_parse_dt(pdev, ts); + if (error) + return error; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + ts->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(ts->base)) + return PTR_ERR(ts->base); + + poll_dev = devm_input_allocate_polled_device(&pdev->dev); + if (!poll_dev) + return -ENOMEM; + + snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&pdev->dev)); + ts->poll_dev = poll_dev; + ts->dev = &pdev->dev; + + poll_dev->private = ts; + poll_dev->poll_interval = POLL_INTERVAL; + poll_dev->open = ts4800_ts_open; + poll_dev->close = ts4800_ts_close; + poll_dev->poll = ts4800_ts_poll; + + poll_dev->input->name = "TS-4800 Touchscreen"; + poll_dev->input->phys = ts->phys; + + input_set_capability(poll_dev->input, EV_KEY, BTN_TOUCH); + input_set_abs_params(poll_dev->input, ABS_X, 0, MAX_12BIT, 0, 0); + input_set_abs_params(poll_dev->input, ABS_Y, 0, MAX_12BIT, 0, 0); + + error = input_register_polled_device(poll_dev); + if (error) { + dev_err(&pdev->dev, + "Unabled to register polled input device (%d)\n", + error); + return error; + } + + return 0; +} + +static const struct of_device_id ts4800_ts_of_match[] = { + { .compatible = "technologic,ts4800-ts", }, + { }, +}; +MODULE_DEVICE_TABLE(of, ts4800_ts_of_match); + +static struct platform_driver ts4800_ts_driver = { + .driver = { + .name = "ts4800-ts", + .of_match_table = ts4800_ts_of_match, + }, + .probe = ts4800_ts_probe, +}; +module_platform_driver(ts4800_ts_driver); + +MODULE_AUTHOR("Damien Riegel "); +MODULE_DESCRIPTION("TS-4800 Touchscreen Driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:ts4800_ts");