diff options
Diffstat (limited to 'drivers/input/touchscreen/atmel_tsadcc.c')
| -rw-r--r-- | drivers/input/touchscreen/atmel_tsadcc.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/atmel_tsadcc.c b/drivers/input/touchscreen/atmel_tsadcc.c new file mode 100644 index 0000000..a89a6a8 --- /dev/null +++ b/drivers/input/touchscreen/atmel_tsadcc.c @@ -0,0 +1,343 @@ +/* + * Atmel Touch Screen Driver + * + * Copyright (c) 2008 ATMEL + * Copyright (c) 2008 Dan Liang + * Copyright (c) 2008 TimeSys Corporation + * Copyright (c) 2008 Justin Waters + * + * Based on touchscreen code from Atmel Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/init.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/input.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/io.h> + +/* Register definitions based on AT91SAM9RL64 preliminary draft datasheet */ + +#define ATMEL_TSADCC_CR 0x00 /* Control register */ +#define ATMEL_TSADCC_SWRST (1 << 0) /* Software Reset*/ +#define ATMEL_TSADCC_START (1 << 1) /* Start conversion */ + +#define ATMEL_TSADCC_MR 0x04 /* Mode register */ +#define ATMEL_TSADCC_TSAMOD (3 << 0) /* ADC mode */ +#define ATMEL_TSADCC_TSAMOD_ADC_ONLY_MODE (0x0) /* ADC Mode */ +#define ATMEL_TSADCC_TSAMOD_TS_ONLY_MODE (0x1) /* Touch Screen Only Mode */ +#define ATMEL_TSADCC_LOWRES (1 << 4) /* Resolution selection */ +#define ATMEL_TSADCC_SLEEP (1 << 5) /* Sleep mode */ +#define ATMEL_TSADCC_PENDET (1 << 6) /* Pen Detect selection */ +#define ATMEL_TSADCC_PRESCAL (0x3f << 8) /* Prescalar Rate Selection */ +#define ATMEL_TSADCC_STARTUP (0x7f << 16) /* Start Up time */ +#define ATMEL_TSADCC_SHTIM (0xf << 24) /* Sample & Hold time */ +#define ATMEL_TSADCC_PENDBC (0xf << 28) /* Pen Detect debouncing time */ + +#define ATMEL_TSADCC_TRGR 0x08 /* Trigger register */ +#define ATMEL_TSADCC_TRGMOD (7 << 0) /* Trigger mode */ +#define ATMEL_TSADCC_TRGMOD_NONE (0 << 0) +#define ATMEL_TSADCC_TRGMOD_EXT_RISING (1 << 0) +#define ATMEL_TSADCC_TRGMOD_EXT_FALLING (2 << 0) +#define ATMEL_TSADCC_TRGMOD_EXT_ANY (3 << 0) +#define ATMEL_TSADCC_TRGMOD_PENDET (4 << 0) +#define ATMEL_TSADCC_TRGMOD_PERIOD (5 << 0) +#define ATMEL_TSADCC_TRGMOD_CONTINUOUS (6 << 0) +#define ATMEL_TSADCC_TRGPER (0xffff << 16) /* Trigger period */ + +#define ATMEL_TSADCC_TSR 0x0C /* Touch Screen register */ +#define ATMEL_TSADCC_TSFREQ (0xf << 0) /* TS Frequency in Interleaved mode */ +#define ATMEL_TSADCC_TSSHTIM (0xf << 24) /* Sample & Hold time */ + +#define ATMEL_TSADCC_CHER 0x10 /* Channel Enable register */ +#define ATMEL_TSADCC_CHDR 0x14 /* Channel Disable register */ +#define ATMEL_TSADCC_CHSR 0x18 /* Channel Status register */ +#define ATMEL_TSADCC_CH(n) (1 << (n)) /* Channel number */ + +#define ATMEL_TSADCC_SR 0x1C /* Status register */ +#define ATMEL_TSADCC_EOC(n) (1 << ((n)+0)) /* End of conversion for channel N */ +#define ATMEL_TSADCC_OVRE(n) (1 << ((n)+8)) /* Overrun error for channel N */ +#define ATMEL_TSADCC_DRDY (1 << 16) /* Data Ready */ +#define ATMEL_TSADCC_GOVRE (1 << 17) /* General Overrun Error */ +#define ATMEL_TSADCC_ENDRX (1 << 18) /* End of RX Buffer */ +#define ATMEL_TSADCC_RXBUFF (1 << 19) /* TX Buffer full */ +#define ATMEL_TSADCC_PENCNT (1 << 20) /* Pen contact */ +#define ATMEL_TSADCC_NOCNT (1 << 21) /* No contact */ + +#define ATMEL_TSADCC_LCDR 0x20 /* Last Converted Data register */ +#define ATMEL_TSADCC_DATA (0x3ff << 0) /* Channel data */ + +#define ATMEL_TSADCC_IER 0x24 /* Interrupt Enable register */ +#define ATMEL_TSADCC_IDR 0x28 /* Interrupt Disable register */ +#define ATMEL_TSADCC_IMR 0x2C /* Interrupt Mask register */ +#define ATMEL_TSADCC_CDR0 0x30 /* Channel Data 0 */ +#define ATMEL_TSADCC_CDR1 0x34 /* Channel Data 1 */ +#define ATMEL_TSADCC_CDR2 0x38 /* Channel Data 2 */ +#define ATMEL_TSADCC_CDR3 0x3C /* Channel Data 3 */ +#define ATMEL_TSADCC_CDR4 0x40 /* Channel Data 4 */ +#define ATMEL_TSADCC_CDR5 0x44 /* Channel Data 5 */ + +#define ADC_CLOCK 1000000 + +struct atmel_tsadcc { + struct input_dev *input; + char phys[32]; + struct clk *clk; + int irq; + unsigned int prev_absx; + unsigned int prev_absy; + unsigned char bufferedmeasure; +}; + +static void __iomem *tsc_base; + +#define atmel_tsadcc_read(reg) __raw_readl(tsc_base + (reg)) +#define atmel_tsadcc_write(reg, val) __raw_writel((val), tsc_base + (reg)) + +static irqreturn_t atmel_tsadcc_interrupt(int irq, void *dev) +{ + struct atmel_tsadcc *ts_dev = (struct atmel_tsadcc *)dev; + struct input_dev *input_dev = ts_dev->input; + + unsigned int status; + unsigned int reg; + + status = atmel_tsadcc_read(ATMEL_TSADCC_SR); + status &= atmel_tsadcc_read(ATMEL_TSADCC_IMR); + + if (status & ATMEL_TSADCC_NOCNT) { + /* Contact lost */ + reg = atmel_tsadcc_read(ATMEL_TSADCC_MR) | ATMEL_TSADCC_PENDBC; + + atmel_tsadcc_write(ATMEL_TSADCC_MR, reg); + atmel_tsadcc_write(ATMEL_TSADCC_TRGR, ATMEL_TSADCC_TRGMOD_NONE); + atmel_tsadcc_write(ATMEL_TSADCC_IDR, + ATMEL_TSADCC_EOC(3) | ATMEL_TSADCC_NOCNT); + atmel_tsadcc_write(ATMEL_TSADCC_IER, ATMEL_TSADCC_PENCNT); + + input_report_key(input_dev, BTN_TOUCH, 0); + ts_dev->bufferedmeasure = 0; + input_sync(input_dev); + + } else if (status & ATMEL_TSADCC_PENCNT) { + /* Pen detected */ + reg = atmel_tsadcc_read(ATMEL_TSADCC_MR); + reg &= ~ATMEL_TSADCC_PENDBC; + + atmel_tsadcc_write(ATMEL_TSADCC_IDR, ATMEL_TSADCC_PENCNT); + atmel_tsadcc_write(ATMEL_TSADCC_MR, reg); + atmel_tsadcc_write(ATMEL_TSADCC_IER, + ATMEL_TSADCC_EOC(3) | ATMEL_TSADCC_NOCNT); + atmel_tsadcc_write(ATMEL_TSADCC_TRGR, + ATMEL_TSADCC_TRGMOD_PERIOD | (0x0FFF << 16)); + + } else if (status & ATMEL_TSADCC_EOC(3)) { + /* Conversion finished */ + + if (ts_dev->bufferedmeasure) { + /* Last measurement is always discarded, since it can + * be erroneous. + * Always report previous measurement */ + input_report_abs(input_dev, ABS_X, ts_dev->prev_absx); + input_report_abs(input_dev, ABS_Y, ts_dev->prev_absy); + input_report_key(input_dev, BTN_TOUCH, 1); + input_sync(input_dev); + } else + ts_dev->bufferedmeasure = 1; + + /* Now make new measurement */ + ts_dev->prev_absx = atmel_tsadcc_read(ATMEL_TSADCC_CDR3) << 10; + ts_dev->prev_absx /= atmel_tsadcc_read(ATMEL_TSADCC_CDR2); + + ts_dev->prev_absy = atmel_tsadcc_read(ATMEL_TSADCC_CDR1) << 10; + ts_dev->prev_absy /= atmel_tsadcc_read(ATMEL_TSADCC_CDR0); + } + + return IRQ_HANDLED; +} + +/* + * The functions for inserting/removing us as a module. + */ + +static int __devinit atmel_tsadcc_probe(struct platform_device *pdev) +{ + struct atmel_tsadcc *ts_dev; + struct input_dev *input_dev; + struct resource *res; + int err = 0; + unsigned int prsc; + unsigned int reg; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "no mmio resource defined.\n"); + return -ENXIO; + } + + /* Allocate memory for device */ + ts_dev = kzalloc(sizeof(struct atmel_tsadcc), GFP_KERNEL); + if (!ts_dev) { + dev_err(&pdev->dev, "failed to allocate memory.\n"); + return -ENOMEM; + } + platform_set_drvdata(pdev, ts_dev); + + input_dev = input_allocate_device(); + if (!input_dev) { + dev_err(&pdev->dev, "failed to allocate input device.\n"); + err = -EBUSY; + goto err_free_mem; + } + + ts_dev->irq = platform_get_irq(pdev, 0); + if (ts_dev->irq < 0) { + dev_err(&pdev->dev, "no irq ID is designated.\n"); + err = -ENODEV; + goto err_free_dev; + } + + if (!request_mem_region(res->start, res->end - res->start + 1, + "atmel tsadcc regs")) { + dev_err(&pdev->dev, "resources is unavailable.\n"); + err = -EBUSY; + goto err_free_dev; + } + + tsc_base = ioremap(res->start, res->end - res->start + 1); + if (!tsc_base) { + dev_err(&pdev->dev, "failed to map registers.\n"); + err = -ENOMEM; + goto err_release_mem; + } + + err = request_irq(ts_dev->irq, atmel_tsadcc_interrupt, IRQF_DISABLED, + pdev->dev.driver->name, ts_dev); + if (err) { + dev_err(&pdev->dev, "failed to allocate irq.\n"); + goto err_unmap_regs; + } + + ts_dev->clk = clk_get(&pdev->dev, "tsc_clk"); + if (IS_ERR(ts_dev->clk)) { + dev_err(&pdev->dev, "failed to get ts_clk\n"); + err = PTR_ERR(ts_dev->clk); + goto err_free_irq; + } + + ts_dev->input = input_dev; + ts_dev->bufferedmeasure = 0; + + snprintf(ts_dev->phys, sizeof(ts_dev->phys), + "%s/input0", pdev->dev.bus_id); + + input_dev->name = "atmel touch screen controller"; + input_dev->phys = ts_dev->phys; + input_dev->dev.parent = &pdev->dev; + + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + + input_set_abs_params(input_dev, ABS_X, 0, 0x3FF, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, 0x3FF, 0, 0); + + /* clk_enable() always returns 0, no need to check it */ + clk_enable(ts_dev->clk); + + prsc = clk_get_rate(ts_dev->clk); + dev_info(&pdev->dev, "Master clock is set at: %d Hz\n", prsc); + + prsc = prsc / ADC_CLOCK / 2 - 1; + + reg = ATMEL_TSADCC_TSAMOD_TS_ONLY_MODE | + ((0x00 << 5) & ATMEL_TSADCC_SLEEP) | /* Normal Mode */ + ((0x01 << 6) & ATMEL_TSADCC_PENDET) | /* Enable Pen Detect */ + ((prsc << 8) & ATMEL_TSADCC_PRESCAL) | /* PRESCAL */ + ((0x13 << 16) & ATMEL_TSADCC_STARTUP) | /* STARTUP */ + ((0x0F << 28) & ATMEL_TSADCC_PENDBC); /* PENDBC */ + + atmel_tsadcc_write(ATMEL_TSADCC_CR, ATMEL_TSADCC_SWRST); + atmel_tsadcc_write(ATMEL_TSADCC_MR, reg); + atmel_tsadcc_write(ATMEL_TSADCC_TRGR, ATMEL_TSADCC_TRGMOD_NONE); + atmel_tsadcc_write(ATMEL_TSADCC_TSR, (0x3 << 24) & ATMEL_TSADCC_TSSHTIM); + + atmel_tsadcc_read(ATMEL_TSADCC_SR); + atmel_tsadcc_write(ATMEL_TSADCC_IER, ATMEL_TSADCC_PENCNT); + + /* All went ok, so register to the input system */ + err = input_register_device(input_dev); + if (err) + goto err_fail; + + return 0; + +err_fail: + clk_disable(ts_dev->clk); + clk_put(ts_dev->clk); +err_free_irq: + free_irq(ts_dev->irq, ts_dev); +err_unmap_regs: + iounmap(tsc_base); +err_release_mem: + release_mem_region(res->start, res->end - res->start + 1); +err_free_dev: + input_free_device(ts_dev->input); +err_free_mem: + kfree(ts_dev); + return err; +} + +static int __devexit atmel_tsadcc_remove(struct platform_device *pdev) +{ + struct atmel_tsadcc *ts_dev = dev_get_drvdata(&pdev->dev); + struct resource *res; + + free_irq(ts_dev->irq, ts_dev); + + input_unregister_device(ts_dev->input); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + iounmap(tsc_base); + release_mem_region(res->start, res->end - res->start + 1); + + clk_disable(ts_dev->clk); + clk_put(ts_dev->clk); + + kfree(ts_dev); + + return 0; +} + +static struct platform_driver atmel_tsadcc_driver = { + .probe = atmel_tsadcc_probe, + .remove = __devexit_p(atmel_tsadcc_remove), + .driver = { + .name = "atmel_tsadcc", + }, +}; + +static int __init atmel_tsadcc_init(void) +{ + return platform_driver_register(&atmel_tsadcc_driver); +} + +static void __exit atmel_tsadcc_exit(void) +{ + platform_driver_unregister(&atmel_tsadcc_driver); +} + +module_init(atmel_tsadcc_init); +module_exit(atmel_tsadcc_exit); + + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Atmel TouchScreen Driver"); +MODULE_AUTHOR("Dan Liang <dan.liang@atmel.com>"); + |
