diff options
Diffstat (limited to 'drivers/input/touchscreen/s3c2410_ts.c')
-rw-r--r-- | drivers/input/touchscreen/s3c2410_ts.c | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/s3c2410_ts.c b/drivers/input/touchscreen/s3c2410_ts.c new file mode 100644 index 000000000000..6386b441ef85 --- /dev/null +++ b/drivers/input/touchscreen/s3c2410_ts.c @@ -0,0 +1,457 @@ +/* + * Samsung S3C24XX touchscreen driver + * + * This program is free software; you can redistribute it and/or modify + * it under the term 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org> + * Copyright 2008 Ben Dooks <ben-linux@fluff.org> + * Copyright 2009 Simtec Electronics <linux@simtec.co.uk> + * + * Additional work by Herbert Pƶtzl <herbert@13thfloor.at> and + * Harald Welte <laforge@openmoko.org> + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/gpio.h> +#include <linux/input.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include <plat/adc.h> +#include <plat/regs-adc.h> + +#include <mach/regs-gpio.h> +#include <mach/ts.h> + +#define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0)) + +#define INT_DOWN (0) +#define INT_UP (1 << 8) + +#define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \ + S3C2410_ADCTSC_YP_SEN | \ + S3C2410_ADCTSC_XP_SEN | \ + S3C2410_ADCTSC_XY_PST(3)) + +#define AUTOPST (S3C2410_ADCTSC_YM_SEN | \ + S3C2410_ADCTSC_YP_SEN | \ + S3C2410_ADCTSC_XP_SEN | \ + S3C2410_ADCTSC_AUTO_PST | \ + S3C2410_ADCTSC_XY_PST(0)) + +/* Per-touchscreen data. */ + +/** + * struct s3c2410ts - driver touchscreen state. + * @client: The ADC client we registered with the core driver. + * @dev: The device we are bound to. + * @input: The input device we registered with the input subsystem. + * @clock: The clock for the adc. + * @io: Pointer to the IO base. + * @xp: The accumulated X position data. + * @yp: The accumulated Y position data. + * @irq_tc: The interrupt number for pen up/down interrupt + * @count: The number of samples collected. + * @shift: The log2 of the maximum count to read in one go. + */ +struct s3c2410ts { + struct s3c_adc_client *client; + struct device *dev; + struct input_dev *input; + struct clk *clock; + void __iomem *io; + unsigned long xp; + unsigned long yp; + int irq_tc; + int count; + int shift; +}; + +static struct s3c2410ts ts; + +/** + * s3c2410_ts_connect - configure gpio for s3c2410 systems + * + * Configure the GPIO for the S3C2410 system, where we have external FETs + * connected to the device (later systems such as the S3C2440 integrate + * these into the device). +*/ +static inline void s3c2410_ts_connect(void) +{ + s3c2410_gpio_cfgpin(S3C2410_GPG(12), S3C2410_GPG12_XMON); + s3c2410_gpio_cfgpin(S3C2410_GPG(13), S3C2410_GPG13_nXPON); + s3c2410_gpio_cfgpin(S3C2410_GPG(14), S3C2410_GPG14_YMON); + s3c2410_gpio_cfgpin(S3C2410_GPG(15), S3C2410_GPG15_nYPON); +} + +/** + * get_down - return the down state of the pen + * @data0: The data read from ADCDAT0 register. + * @data1: The data read from ADCDAT1 register. + * + * Return non-zero if both readings show that the pen is down. + */ +static inline bool get_down(unsigned long data0, unsigned long data1) +{ + /* returns true if both data values show stylus down */ + return (!(data0 & S3C2410_ADCDAT0_UPDOWN) && + !(data1 & S3C2410_ADCDAT0_UPDOWN)); +} + +static void touch_timer_fire(unsigned long data) +{ + unsigned long data0; + unsigned long data1; + bool down; + + data0 = readl(ts.io + S3C2410_ADCDAT0); + data1 = readl(ts.io + S3C2410_ADCDAT1); + + down = get_down(data0, data1); + + if (ts.count == (1 << ts.shift)) { + ts.xp >>= ts.shift; + ts.yp >>= ts.shift; + + dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n", + __func__, ts.xp, ts.yp, ts.count); + + input_report_abs(ts.input, ABS_X, ts.xp); + input_report_abs(ts.input, ABS_Y, ts.yp); + + input_report_key(ts.input, BTN_TOUCH, 1); + input_sync(ts.input); + + ts.xp = 0; + ts.yp = 0; + ts.count = 0; + } + + if (down) { + s3c_adc_start(ts.client, 0, 1 << ts.shift); + } else { + ts.count = 0; + + input_report_key(ts.input, BTN_TOUCH, 0); + input_sync(ts.input); + + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); + } +} + +static DEFINE_TIMER(touch_timer, touch_timer_fire, 0, 0); + +/** + * stylus_irq - touchscreen stylus event interrupt + * @irq: The interrupt number + * @dev_id: The device ID. + * + * Called when the IRQ_TC is fired for a pen up or down event. + */ +static irqreturn_t stylus_irq(int irq, void *dev_id) +{ + unsigned long data0; + unsigned long data1; + bool down; + + data0 = readl(ts.io + S3C2410_ADCDAT0); + data1 = readl(ts.io + S3C2410_ADCDAT1); + + down = get_down(data0, data1); + + /* TODO we should never get an interrupt with down set while + * the timer is running, but maybe we ought to verify that the + * timer isn't running anyways. */ + + if (down) + s3c_adc_start(ts.client, 0, 1 << ts.shift); + else + dev_info(ts.dev, "%s: count=%d\n", __func__, ts.count); + + return IRQ_HANDLED; +} + +/** + * s3c24xx_ts_conversion - ADC conversion callback + * @client: The client that was registered with the ADC core. + * @data0: The reading from ADCDAT0. + * @data1: The reading from ADCDAT1. + * @left: The number of samples left. + * + * Called when a conversion has finished. + */ +static void s3c24xx_ts_conversion(struct s3c_adc_client *client, + unsigned data0, unsigned data1, + unsigned *left) +{ + dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1); + + ts.xp += data0; + ts.yp += data1; + + ts.count++; + + /* From tests, it seems that it is unlikely to get a pen-up + * event during the conversion process which means we can + * ignore any pen-up events with less than the requisite + * count done. + * + * In several thousand conversions, no pen-ups where detected + * before count completed. + */ +} + +/** + * s3c24xx_ts_select - ADC selection callback. + * @client: The client that was registered with the ADC core. + * @select: The reason for select. + * + * Called when the ADC core selects (or deslects) us as a client. + */ +static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select) +{ + if (select) { + writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST, + ts.io + S3C2410_ADCTSC); + } else { + mod_timer(&touch_timer, jiffies+1); + writel(WAIT4INT | INT_UP, ts.io + S3C2410_ADCTSC); + } +} + +/** + * s3c2410ts_probe - device core probe entry point + * @pdev: The device we are being bound to. + * + * Initialise, find and allocate any resources we need to run and then + * register with the ADC and input systems. + */ +static int __devinit s3c2410ts_probe(struct platform_device *pdev) +{ + struct s3c2410_ts_mach_info *info; + struct device *dev = &pdev->dev; + struct input_dev *input_dev; + struct resource *res; + int ret = -EINVAL; + + /* Initialise input stuff */ + memset(&ts, 0, sizeof(struct s3c2410ts)); + + ts.dev = dev; + + info = pdev->dev.platform_data; + if (!info) { + dev_err(dev, "no platform data, cannot attach\n"); + return -EINVAL; + } + + dev_dbg(dev, "initialising touchscreen\n"); + + ts.clock = clk_get(dev, "adc"); + if (IS_ERR(ts.clock)) { + dev_err(dev, "cannot get adc clock source\n"); + return -ENOENT; + } + + clk_enable(ts.clock); + dev_dbg(dev, "got and enabled clocks\n"); + + ts.irq_tc = ret = platform_get_irq(pdev, 0); + if (ret < 0) { + dev_err(dev, "no resource for interrupt\n"); + goto err_clk; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "no resource for registers\n"); + ret = -ENOENT; + goto err_clk; + } + + ts.io = ioremap(res->start, resource_size(res)); + if (ts.io == NULL) { + dev_err(dev, "cannot map registers\n"); + ret = -ENOMEM; + goto err_clk; + } + + /* Configure the touchscreen external FETs on the S3C2410 */ + if (!platform_get_device_id(pdev)->driver_data) + s3c2410_ts_connect(); + + ts.client = s3c_adc_register(pdev, s3c24xx_ts_select, + s3c24xx_ts_conversion, 1); + if (IS_ERR(ts.client)) { + dev_err(dev, "failed to register adc client\n"); + ret = PTR_ERR(ts.client); + goto err_iomap; + } + + /* Initialise registers */ + if ((info->delay & 0xffff) > 0) + writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY); + + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); + + input_dev = input_allocate_device(); + if (!input_dev) { + dev_err(dev, "Unable to allocate the input device !!\n"); + ret = -ENOMEM; + goto err_iomap; + } + + ts.input = input_dev; + ts.input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0); + input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0); + + ts.input->name = "S3C24XX TouchScreen"; + ts.input->id.bustype = BUS_HOST; + ts.input->id.vendor = 0xDEAD; + ts.input->id.product = 0xBEEF; + ts.input->id.version = 0x0102; + + ts.shift = info->oversampling_shift; + + ret = request_irq(ts.irq_tc, stylus_irq, IRQF_DISABLED, + "s3c2410_ts_pen", ts.input); + if (ret) { + dev_err(dev, "cannot get TC interrupt\n"); + goto err_inputdev; + } + + dev_info(dev, "driver attached, registering input device\n"); + + /* All went ok, so register to the input system */ + ret = input_register_device(ts.input); + if (ret < 0) { + dev_err(dev, "failed to register input device\n"); + ret = -EIO; + goto err_tcirq; + } + + return 0; + + err_tcirq: + free_irq(ts.irq_tc, ts.input); + err_inputdev: + input_unregister_device(ts.input); + err_iomap: + iounmap(ts.io); + err_clk: + del_timer_sync(&touch_timer); + clk_put(ts.clock); + return ret; +} + +/** + * s3c2410ts_remove - device core removal entry point + * @pdev: The device we are being removed from. + * + * Free up our state ready to be removed. + */ +static int __devexit s3c2410ts_remove(struct platform_device *pdev) +{ + free_irq(ts.irq_tc, ts.input); + del_timer_sync(&touch_timer); + + clk_disable(ts.clock); + clk_put(ts.clock); + + input_unregister_device(ts.input); + iounmap(ts.io); + + return 0; +} + +#ifdef CONFIG_PM +static int s3c2410ts_suspend(struct device *dev) +{ + writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC); + disable_irq(ts.irq_tc); + clk_disable(ts.clock); + + return 0; +} + +static int s3c2410ts_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct s3c2410_ts_mach_info *info = pdev->dev.platform_data; + + clk_enable(ts.clock); + + /* Initialise registers */ + if ((info->delay & 0xffff) > 0) + writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY); + + writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); + + return 0; +} + +static struct dev_pm_ops s3c_ts_pmops = { + .suspend = s3c2410ts_suspend, + .resume = s3c2410ts_resume, +}; +#endif + +static struct platform_device_id s3cts_driver_ids[] = { + { "s3c2410-ts", 0 }, + { "s3c2440-ts", 1 }, + { } +}; +MODULE_DEVICE_TABLE(platform, s3cts_driver_ids); + +static struct platform_driver s3c_ts_driver = { + .driver = { + .name = "s3c24xx-ts", + .owner = THIS_MODULE, +#ifdef CONFIG_PM + .pm = &s3c_ts_pmops, +#endif + }, + .id_table = s3cts_driver_ids, + .probe = s3c2410ts_probe, + .remove = __devexit_p(s3c2410ts_remove), +}; + +static int __init s3c2410ts_init(void) +{ + return platform_driver_register(&s3c_ts_driver); +} + +static void __exit s3c2410ts_exit(void) +{ + platform_driver_unregister(&s3c_ts_driver); +} + +module_init(s3c2410ts_init); +module_exit(s3c2410ts_exit); + +MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>, " + "Ben Dooks <ben@simtec.co.uk>, " + "Simtec Electronics <linux@simtec.co.uk>"); +MODULE_DESCRIPTION("S3C24XX Touchscreen driver"); +MODULE_LICENSE("GPL v2"); |