diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-04-14 13:18:27 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2012-04-14 13:19:04 +0200 |
| commit | 6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch) | |
| tree | 021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /drivers/input/touchscreen/ti_tscadc.c | |
| parent | 682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff) | |
| parent | a385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff) | |
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/input/touchscreen/ti_tscadc.c')
| -rw-r--r-- | drivers/input/touchscreen/ti_tscadc.c | 486 |
1 files changed, 486 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ti_tscadc.c b/drivers/input/touchscreen/ti_tscadc.c new file mode 100644 index 000000000000..d229c741d544 --- /dev/null +++ b/drivers/input/touchscreen/ti_tscadc.c @@ -0,0 +1,486 @@ +/* + * TI Touch Screen driver + * + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/err.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> +#include <linux/input/ti_tscadc.h> +#include <linux/delay.h> + +#define REG_IRQEOI 0x020 +#define REG_RAWIRQSTATUS 0x024 +#define REG_IRQSTATUS 0x028 +#define REG_IRQENABLE 0x02C +#define REG_IRQWAKEUP 0x034 +#define REG_CTRL 0x040 +#define REG_ADCFSM 0x044 +#define REG_CLKDIV 0x04C +#define REG_SE 0x054 +#define REG_IDLECONFIG 0x058 +#define REG_CHARGECONFIG 0x05C +#define REG_CHARGEDELAY 0x060 +#define REG_STEPCONFIG(n) (0x64 + ((n - 1) * 8)) +#define REG_STEPDELAY(n) (0x68 + ((n - 1) * 8)) +#define REG_STEPCONFIG13 0x0C4 +#define REG_STEPDELAY13 0x0C8 +#define REG_STEPCONFIG14 0x0CC +#define REG_STEPDELAY14 0x0D0 +#define REG_FIFO0CNT 0xE4 +#define REG_FIFO1THR 0xF4 +#define REG_FIFO0 0x100 +#define REG_FIFO1 0x200 + +/* Register Bitfields */ +#define IRQWKUP_ENB BIT(0) +#define STPENB_STEPENB 0x7FFF +#define IRQENB_FIFO1THRES BIT(5) +#define IRQENB_PENUP BIT(9) +#define STEPCONFIG_MODE_HWSYNC 0x2 +#define STEPCONFIG_SAMPLES_AVG (1 << 4) +#define STEPCONFIG_XPP (1 << 5) +#define STEPCONFIG_XNN (1 << 6) +#define STEPCONFIG_YPP (1 << 7) +#define STEPCONFIG_YNN (1 << 8) +#define STEPCONFIG_XNP (1 << 9) +#define STEPCONFIG_YPN (1 << 10) +#define STEPCONFIG_INM (1 << 18) +#define STEPCONFIG_INP (1 << 20) +#define STEPCONFIG_INP_5 (1 << 21) +#define STEPCONFIG_FIFO1 (1 << 26) +#define STEPCONFIG_OPENDLY 0xff +#define STEPCONFIG_Z1 (3 << 19) +#define STEPIDLE_INP (1 << 22) +#define STEPCHARGE_RFP (1 << 12) +#define STEPCHARGE_INM (1 << 15) +#define STEPCHARGE_INP (1 << 19) +#define STEPCHARGE_RFM (1 << 23) +#define STEPCHARGE_DELAY 0x1 +#define CNTRLREG_TSCSSENB (1 << 0) +#define CNTRLREG_STEPID (1 << 1) +#define CNTRLREG_STEPCONFIGWRT (1 << 2) +#define CNTRLREG_4WIRE (1 << 5) +#define CNTRLREG_5WIRE (1 << 6) +#define CNTRLREG_8WIRE (3 << 5) +#define CNTRLREG_TSCENB (1 << 7) +#define ADCFSM_STEPID 0x10 + +#define SEQ_SETTLE 275 +#define ADC_CLK 3000000 +#define MAX_12BIT ((1 << 12) - 1) +#define TSCADC_DELTA_X 15 +#define TSCADC_DELTA_Y 15 + +struct tscadc { + struct input_dev *input; + struct clk *tsc_ick; + void __iomem *tsc_base; + unsigned int irq; + unsigned int wires; + unsigned int x_plate_resistance; + bool pen_down; +}; + +static unsigned int tscadc_readl(struct tscadc *ts, unsigned int reg) +{ + return readl(ts->tsc_base + reg); +} + +static void tscadc_writel(struct tscadc *tsc, unsigned int reg, + unsigned int val) +{ + writel(val, tsc->tsc_base + reg); +} + +static void tscadc_step_config(struct tscadc *ts_dev) +{ + unsigned int config; + int i; + + /* Configure the Step registers */ + + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_SAMPLES_AVG | STEPCONFIG_XPP; + switch (ts_dev->wires) { + case 4: + config |= STEPCONFIG_INP | STEPCONFIG_XNN; + break; + case 5: + config |= STEPCONFIG_YNN | + STEPCONFIG_INP_5 | STEPCONFIG_XNN | + STEPCONFIG_YPP; + break; + case 8: + config |= STEPCONFIG_INP | STEPCONFIG_XNN; + break; + } + + for (i = 1; i < 7; i++) { + tscadc_writel(ts_dev, REG_STEPCONFIG(i), config); + tscadc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY); + } + + config = 0; + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_SAMPLES_AVG | STEPCONFIG_YNN | + STEPCONFIG_INM | STEPCONFIG_FIFO1; + switch (ts_dev->wires) { + case 4: + config |= STEPCONFIG_YPP; + break; + case 5: + config |= STEPCONFIG_XPP | STEPCONFIG_INP_5 | + STEPCONFIG_XNP | STEPCONFIG_YPN; + break; + case 8: + config |= STEPCONFIG_YPP; + break; + } + + for (i = 7; i < 13; i++) { + tscadc_writel(ts_dev, REG_STEPCONFIG(i), config); + tscadc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY); + } + + config = 0; + /* Charge step configuration */ + config = STEPCONFIG_XPP | STEPCONFIG_YNN | + STEPCHARGE_RFP | STEPCHARGE_RFM | + STEPCHARGE_INM | STEPCHARGE_INP; + + tscadc_writel(ts_dev, REG_CHARGECONFIG, config); + tscadc_writel(ts_dev, REG_CHARGEDELAY, STEPCHARGE_DELAY); + + config = 0; + /* Configure to calculate pressure */ + config = STEPCONFIG_MODE_HWSYNC | + STEPCONFIG_SAMPLES_AVG | STEPCONFIG_YPP | + STEPCONFIG_XNN | STEPCONFIG_INM; + tscadc_writel(ts_dev, REG_STEPCONFIG13, config); + tscadc_writel(ts_dev, REG_STEPDELAY13, STEPCONFIG_OPENDLY); + + config |= STEPCONFIG_Z1 | STEPCONFIG_FIFO1; + tscadc_writel(ts_dev, REG_STEPCONFIG14, config); + tscadc_writel(ts_dev, REG_STEPDELAY14, STEPCONFIG_OPENDLY); + + tscadc_writel(ts_dev, REG_SE, STPENB_STEPENB); +} + +static void tscadc_idle_config(struct tscadc *ts_config) +{ + unsigned int idleconfig; + + idleconfig = STEPCONFIG_YNN | + STEPCONFIG_INM | + STEPCONFIG_YPN | STEPIDLE_INP; + tscadc_writel(ts_config, REG_IDLECONFIG, idleconfig); +} + +static void tscadc_read_coordinates(struct tscadc *ts_dev, + unsigned int *x, unsigned int *y) +{ + unsigned int fifocount = tscadc_readl(ts_dev, REG_FIFO0CNT); + unsigned int prev_val_x = ~0, prev_val_y = ~0; + unsigned int prev_diff_x = ~0, prev_diff_y = ~0; + unsigned int read, diff; + unsigned int i; + + /* + * Delta filter is used to remove large variations in sampled + * values from ADC. The filter tries to predict where the next + * coordinate could be. This is done by taking a previous + * coordinate and subtracting it form current one. Further the + * algorithm compares the difference with that of a present value, + * if true the value is reported to the sub system. + */ + for (i = 0; i < fifocount - 1; i++) { + read = tscadc_readl(ts_dev, REG_FIFO0) & 0xfff; + diff = abs(read - prev_val_x); + if (diff < prev_diff_x) { + prev_diff_x = diff; + *x = read; + } + prev_val_x = read; + + read = tscadc_readl(ts_dev, REG_FIFO1) & 0xfff; + diff = abs(read - prev_val_y); + if (diff < prev_diff_y) { + prev_diff_y = diff; + *y = read; + } + prev_val_y = read; + } +} + +static irqreturn_t tscadc_irq(int irq, void *dev) +{ + struct tscadc *ts_dev = dev; + struct input_dev *input_dev = ts_dev->input; + unsigned int status, irqclr = 0; + unsigned int x = 0, y = 0; + unsigned int z1, z2, z; + unsigned int fsm; + + status = tscadc_readl(ts_dev, REG_IRQSTATUS); + if (status & IRQENB_FIFO1THRES) { + tscadc_read_coordinates(ts_dev, &x, &y); + + z1 = tscadc_readl(ts_dev, REG_FIFO0) & 0xfff; + z2 = tscadc_readl(ts_dev, REG_FIFO1) & 0xfff; + + if (ts_dev->pen_down && z1 != 0 && z2 != 0) { + /* + * Calculate pressure using formula + * Resistance(touch) = x plate resistance * + * x postion/4096 * ((z2 / z1) - 1) + */ + z = z2 - z1; + z *= x; + z *= ts_dev->x_plate_resistance; + z /= z1; + z = (z + 2047) >> 12; + + if (z <= MAX_12BIT) { + input_report_abs(input_dev, ABS_X, x); + input_report_abs(input_dev, ABS_Y, y); + input_report_abs(input_dev, ABS_PRESSURE, z); + input_report_key(input_dev, BTN_TOUCH, 1); + input_sync(input_dev); + } + } + irqclr |= IRQENB_FIFO1THRES; + } + + /* + * Time for sequencer to settle, to read + * correct state of the sequencer. + */ + udelay(SEQ_SETTLE); + + status = tscadc_readl(ts_dev, REG_RAWIRQSTATUS); + if (status & IRQENB_PENUP) { + /* Pen up event */ + fsm = tscadc_readl(ts_dev, REG_ADCFSM); + if (fsm == ADCFSM_STEPID) { + ts_dev->pen_down = false; + input_report_key(input_dev, BTN_TOUCH, 0); + input_report_abs(input_dev, ABS_PRESSURE, 0); + input_sync(input_dev); + } else { + ts_dev->pen_down = true; + } + irqclr |= IRQENB_PENUP; + } + + tscadc_writel(ts_dev, REG_IRQSTATUS, irqclr); + /* check pending interrupts */ + tscadc_writel(ts_dev, REG_IRQEOI, 0x0); + + tscadc_writel(ts_dev, REG_SE, STPENB_STEPENB); + return IRQ_HANDLED; +} + +/* + * The functions for inserting/removing driver as a module. + */ + +static int __devinit tscadc_probe(struct platform_device *pdev) +{ + const struct tsc_data *pdata = pdev->dev.platform_data; + struct resource *res; + struct tscadc *ts_dev; + struct input_dev *input_dev; + struct clk *clk; + int err; + int clk_value, ctrl, irq; + + if (!pdata) { + dev_err(&pdev->dev, "missing platform data.\n"); + return -EINVAL; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "no memory resource defined.\n"); + return -EINVAL; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "no irq ID is specified.\n"); + return -EINVAL; + } + + /* Allocate memory for device */ + ts_dev = kzalloc(sizeof(struct tscadc), GFP_KERNEL); + input_dev = input_allocate_device(); + if (!ts_dev || !input_dev) { + dev_err(&pdev->dev, "failed to allocate memory.\n"); + err = -ENOMEM; + goto err_free_mem; + } + + ts_dev->input = input_dev; + ts_dev->irq = irq; + ts_dev->wires = pdata->wires; + ts_dev->x_plate_resistance = pdata->x_plate_resistance; + + res = request_mem_region(res->start, resource_size(res), pdev->name); + if (!res) { + dev_err(&pdev->dev, "failed to reserve registers.\n"); + err = -EBUSY; + goto err_free_mem; + } + + ts_dev->tsc_base = ioremap(res->start, resource_size(res)); + if (!ts_dev->tsc_base) { + dev_err(&pdev->dev, "failed to map registers.\n"); + err = -ENOMEM; + goto err_release_mem_region; + } + + err = request_irq(ts_dev->irq, tscadc_irq, + 0, pdev->dev.driver->name, ts_dev); + if (err) { + dev_err(&pdev->dev, "failed to allocate irq.\n"); + goto err_unmap_regs; + } + + ts_dev->tsc_ick = clk_get(&pdev->dev, "adc_tsc_ick"); + if (IS_ERR(ts_dev->tsc_ick)) { + dev_err(&pdev->dev, "failed to get TSC ick\n"); + goto err_free_irq; + } + clk_enable(ts_dev->tsc_ick); + + clk = clk_get(&pdev->dev, "adc_tsc_fck"); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "failed to get TSC fck\n"); + err = PTR_ERR(clk); + goto err_disable_clk; + } + + clk_value = clk_get_rate(clk) / ADC_CLK; + clk_put(clk); + + if (clk_value < 7) { + dev_err(&pdev->dev, "clock input less than min clock requirement\n"); + goto err_disable_clk; + } + /* CLKDIV needs to be configured to the value minus 1 */ + tscadc_writel(ts_dev, REG_CLKDIV, clk_value - 1); + + /* Enable wake-up of the SoC using touchscreen */ + tscadc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB); + + ctrl = CNTRLREG_STEPCONFIGWRT | + CNTRLREG_TSCENB | + CNTRLREG_STEPID; + switch (ts_dev->wires) { + case 4: + ctrl |= CNTRLREG_4WIRE; + break; + case 5: + ctrl |= CNTRLREG_5WIRE; + break; + case 8: + ctrl |= CNTRLREG_8WIRE; + break; + } + tscadc_writel(ts_dev, REG_CTRL, ctrl); + + tscadc_idle_config(ts_dev); + tscadc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO1THRES); + tscadc_step_config(ts_dev); + tscadc_writel(ts_dev, REG_FIFO1THR, 6); + + ctrl |= CNTRLREG_TSCSSENB; + tscadc_writel(ts_dev, REG_CTRL, ctrl); + + input_dev->name = "ti-tsc-adc"; + 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, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0); + + /* register to the input system */ + err = input_register_device(input_dev); + if (err) + goto err_disable_clk; + + platform_set_drvdata(pdev, ts_dev); + return 0; + +err_disable_clk: + clk_disable(ts_dev->tsc_ick); + clk_put(ts_dev->tsc_ick); +err_free_irq: + free_irq(ts_dev->irq, ts_dev); +err_unmap_regs: + iounmap(ts_dev->tsc_base); +err_release_mem_region: + release_mem_region(res->start, resource_size(res)); +err_free_mem: + input_free_device(input_dev); + kfree(ts_dev); + return err; +} + +static int __devexit tscadc_remove(struct platform_device *pdev) +{ + struct tscadc *ts_dev = platform_get_drvdata(pdev); + 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(ts_dev->tsc_base); + release_mem_region(res->start, resource_size(res)); + + clk_disable(ts_dev->tsc_ick); + clk_put(ts_dev->tsc_ick); + + kfree(ts_dev); + + platform_set_drvdata(pdev, NULL); + return 0; +} + +static struct platform_driver ti_tsc_driver = { + .probe = tscadc_probe, + .remove = __devexit_p(tscadc_remove), + .driver = { + .name = "tsc", + .owner = THIS_MODULE, + }, +}; +module_platform_driver(ti_tsc_driver); + +MODULE_DESCRIPTION("TI touchscreen controller driver"); +MODULE_AUTHOR("Rachna Patil <rachna@ti.com>"); +MODULE_LICENSE("GPL"); |
