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path: root/drivers/input/touchscreen/atmel_tsadcc.c
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Diffstat (limited to 'drivers/input/touchscreen/atmel_tsadcc.c')
-rw-r--r--drivers/input/touchscreen/atmel_tsadcc.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/atmel_tsadcc.c b/drivers/input/touchscreen/atmel_tsadcc.c
new file mode 100644
index 000000000000..eee126b19e8b
--- /dev/null
+++ b/drivers/input/touchscreen/atmel_tsadcc.c
@@ -0,0 +1,332 @@
+/*
+ * 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;
+};
+
+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 input_dev *input_dev = ((struct atmel_tsadcc *)dev)->input;
+
+ unsigned int absx;
+ unsigned int absy;
+ 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);
+ 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 */
+
+ absx = atmel_tsadcc_read(ATMEL_TSADCC_CDR3) << 10;
+ absx /= atmel_tsadcc_read(ATMEL_TSADCC_CDR2);
+
+ absy = atmel_tsadcc_read(ATMEL_TSADCC_CDR1) << 10;
+ absy /= atmel_tsadcc_read(ATMEL_TSADCC_CDR0);
+
+ input_report_abs(input_dev, ABS_X, absx);
+ input_report_abs(input_dev, ABS_Y, absy);
+ input_report_key(input_dev, BTN_TOUCH, 1);
+ input_sync(input_dev);
+ }
+
+ 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;
+
+ 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>");
+