| /* |
| * ADS7846 based touchscreen and sensor driver |
| * |
| * Copyright (c) 2005 David Brownell |
| * Copyright (c) 2006 Nokia Corporation |
| * Various changes: Imre Deak <imre.deak@nokia.com> |
| * |
| * Using code from: |
| * - corgi_ts.c |
| * Copyright (C) 2004-2005 Richard Purdie |
| * - omap_ts.[hc], ads7846.h, ts_osk.c |
| * Copyright (C) 2002 MontaVista Software |
| * Copyright (C) 2004 Texas Instruments |
| * Copyright (C) 2005 Dirk Behme |
| * |
| * 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/device.h> |
| #include <linux/init.h> |
| #include <linux/delay.h> |
| #include <linux/input.h> |
| #include <linux/interrupt.h> |
| #include <linux/slab.h> |
| #include <linux/spi/spi.h> |
| #include <linux/spi/ads7846.h> |
| #include <asm/irq.h> |
| |
| #ifdef CONFIG_ARM |
| #include <asm/mach-types.h> |
| #ifdef CONFIG_ARCH_OMAP |
| #include <asm/arch/gpio.h> |
| #endif |
| #endif |
| |
| |
| /* |
| * This code has been heavily tested on a Nokia 770, and lightly |
| * tested on other ads7846 devices (OSK/Mistral, Lubbock). |
| * Support for ads7843 and ads7845 has only been stubbed in. |
| * |
| * IRQ handling needs a workaround because of a shortcoming in handling |
| * edge triggered IRQs on some platforms like the OMAP1/2. These |
| * platforms don't handle the ARM lazy IRQ disabling properly, thus we |
| * have to maintain our own SW IRQ disabled status. This should be |
| * removed as soon as the affected platform's IRQ handling is fixed. |
| * |
| * app note sbaa036 talks in more detail about accurate sampling... |
| * that ought to help in situations like LCDs inducing noise (which |
| * can also be helped by using synch signals) and more generally. |
| * This driver tries to utilize the measures described in the app |
| * note. The strength of filtering can be set in the board-* specific |
| * files. |
| */ |
| |
| #define TS_POLL_PERIOD msecs_to_jiffies(10) |
| |
| /* this driver doesn't aim at the peak continuous sample rate */ |
| #define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) |
| |
| struct ts_event { |
| /* For portability, we can't read 12 bit values using SPI (which |
| * would make the controller deliver them as native byteorder u16 |
| * with msbs zeroed). Instead, we read them as two 8-bit values, |
| * which need byteswapping then range adjustment. |
| */ |
| __be16 x; |
| __be16 y; |
| __be16 z1, z2; |
| int ignore; |
| }; |
| |
| struct ads7846 { |
| struct input_dev *input; |
| char phys[32]; |
| |
| struct spi_device *spi; |
| u16 model; |
| u16 vref_delay_usecs; |
| u16 x_plate_ohms; |
| u16 pressure_max; |
| |
| u8 read_x, read_y, read_z1, read_z2, pwrdown; |
| u16 dummy; /* for the pwrdown read */ |
| struct ts_event tc; |
| |
| struct spi_transfer xfer[10]; |
| struct spi_message msg[5]; |
| struct spi_message *last_msg; |
| int msg_idx; |
| int read_cnt; |
| int read_rep; |
| int last_read; |
| |
| u16 debounce_max; |
| u16 debounce_tol; |
| u16 debounce_rep; |
| |
| spinlock_t lock; |
| struct timer_list timer; /* P: lock */ |
| unsigned pendown:1; /* P: lock */ |
| unsigned pending:1; /* P: lock */ |
| // FIXME remove "irq_disabled" |
| unsigned irq_disabled:1; /* P: lock */ |
| unsigned disabled:1; |
| |
| int (*get_pendown_state)(void); |
| }; |
| |
| /* leave chip selected when we're done, for quicker re-select? */ |
| #if 0 |
| #define CS_CHANGE(xfer) ((xfer).cs_change = 1) |
| #else |
| #define CS_CHANGE(xfer) ((xfer).cs_change = 0) |
| #endif |
| |
| /*--------------------------------------------------------------------------*/ |
| |
| /* The ADS7846 has touchscreen and other sensors. |
| * Earlier ads784x chips are somewhat compatible. |
| */ |
| #define ADS_START (1 << 7) |
| #define ADS_A2A1A0_d_y (1 << 4) /* differential */ |
| #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ |
| #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ |
| #define ADS_A2A1A0_d_x (5 << 4) /* differential */ |
| #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ |
| #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ |
| #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ |
| #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ |
| #define ADS_8_BIT (1 << 3) |
| #define ADS_12_BIT (0 << 3) |
| #define ADS_SER (1 << 2) /* non-differential */ |
| #define ADS_DFR (0 << 2) /* differential */ |
| #define ADS_PD10_PDOWN (0 << 0) /* lowpower mode + penirq */ |
| #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ |
| #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ |
| #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ |
| |
| #define MAX_12BIT ((1<<12)-1) |
| |
| /* leave ADC powered up (disables penirq) between differential samples */ |
| #define READ_12BIT_DFR(x) (ADS_START | ADS_A2A1A0_d_ ## x \ |
| | ADS_12_BIT | ADS_DFR) |
| |
| #define READ_Y (READ_12BIT_DFR(y) | ADS_PD10_ADC_ON) |
| #define READ_Z1 (READ_12BIT_DFR(z1) | ADS_PD10_ADC_ON) |
| #define READ_Z2 (READ_12BIT_DFR(z2) | ADS_PD10_ADC_ON) |
| |
| #define READ_X (READ_12BIT_DFR(x) | ADS_PD10_ADC_ON) |
| #define PWRDOWN (READ_12BIT_DFR(y) | ADS_PD10_PDOWN) /* LAST */ |
| |
| /* single-ended samples need to first power up reference voltage; |
| * we leave both ADC and VREF powered |
| */ |
| #define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ |
| | ADS_12_BIT | ADS_SER) |
| |
| #define REF_ON (READ_12BIT_DFR(x) | ADS_PD10_ALL_ON) |
| #define REF_OFF (READ_12BIT_DFR(y) | ADS_PD10_PDOWN) |
| |
| /*--------------------------------------------------------------------------*/ |
| |
| /* |
| * Non-touchscreen sensors only use single-ended conversions. |
| */ |
| |
| struct ser_req { |
| u8 ref_on; |
| u8 command; |
| u8 ref_off; |
| u16 scratch; |
| __be16 sample; |
| struct spi_message msg; |
| struct spi_transfer xfer[6]; |
| }; |
| |
| static void ads7846_enable(struct ads7846 *ts); |
| static void ads7846_disable(struct ads7846 *ts); |
| |
| static int device_suspended(struct device *dev) |
| { |
| struct ads7846 *ts = dev_get_drvdata(dev); |
| return dev->power.power_state.event != PM_EVENT_ON || ts->disabled; |
| } |
| |
| static int ads7846_read12_ser(struct device *dev, unsigned command) |
| { |
| struct spi_device *spi = to_spi_device(dev); |
| struct ads7846 *ts = dev_get_drvdata(dev); |
| struct ser_req *req = kzalloc(sizeof *req, SLAB_KERNEL); |
| int status; |
| int sample; |
| int i; |
| |
| if (!req) |
| return -ENOMEM; |
| |
| spi_message_init(&req->msg); |
| |
| /* activate reference, so it has time to settle; */ |
| req->ref_on = REF_ON; |
| req->xfer[0].tx_buf = &req->ref_on; |
| req->xfer[0].len = 1; |
| req->xfer[1].rx_buf = &req->scratch; |
| req->xfer[1].len = 2; |
| |
| /* |
| * for external VREF, 0 usec (and assume it's always on); |
| * for 1uF, use 800 usec; |
| * no cap, 100 usec. |
| */ |
| req->xfer[1].delay_usecs = ts->vref_delay_usecs; |
| |
| /* take sample */ |
| req->command = (u8) command; |
| req->xfer[2].tx_buf = &req->command; |
| req->xfer[2].len = 1; |
| req->xfer[3].rx_buf = &req->sample; |
| req->xfer[3].len = 2; |
| |
| /* REVISIT: take a few more samples, and compare ... */ |
| |
| /* turn off reference */ |
| req->ref_off = REF_OFF; |
| req->xfer[4].tx_buf = &req->ref_off; |
| req->xfer[4].len = 1; |
| req->xfer[5].rx_buf = &req->scratch; |
| req->xfer[5].len = 2; |
| |
| CS_CHANGE(req->xfer[5]); |
| |
| /* group all the transfers together, so we can't interfere with |
| * reading touchscreen state; disable penirq while sampling |
| */ |
| for (i = 0; i < 6; i++) |
| spi_message_add_tail(&req->xfer[i], &req->msg); |
| |
| ts->irq_disabled = 1; |
| disable_irq(spi->irq); |
| status = spi_sync(spi, &req->msg); |
| ts->irq_disabled = 0; |
| enable_irq(spi->irq); |
| |
| if (req->msg.status) |
| status = req->msg.status; |
| |
| /* on-wire is a must-ignore bit, a BE12 value, then padding */ |
| sample = be16_to_cpu(req->sample); |
| sample = sample >> 3; |
| sample &= 0x0fff; |
| |
| kfree(req); |
| return status ? status : sample; |
| } |
| |
| #define SHOW(name) static ssize_t \ |
| name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
| { \ |
| ssize_t v = ads7846_read12_ser(dev, \ |
| READ_12BIT_SER(name) | ADS_PD10_ALL_ON); \ |
| if (v < 0) \ |
| return v; \ |
| return sprintf(buf, "%u\n", (unsigned) v); \ |
| } \ |
| static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); |
| |
| SHOW(temp0) |
| SHOW(temp1) |
| SHOW(vaux) |
| SHOW(vbatt) |
| |
| static int is_pen_down(struct device *dev) |
| { |
| struct ads7846 *ts = dev_get_drvdata(dev); |
| |
| return ts->pendown; |
| } |
| |
| static ssize_t ads7846_pen_down_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| return sprintf(buf, "%u\n", is_pen_down(dev)); |
| } |
| |
| static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); |
| |
| static ssize_t ads7846_disable_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct ads7846 *ts = dev_get_drvdata(dev); |
| |
| return sprintf(buf, "%u\n", ts->disabled); |
| } |
| |
| static ssize_t ads7846_disable_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct ads7846 *ts = dev_get_drvdata(dev); |
| char *endp; |
| int i; |
| |
| i = simple_strtoul(buf, &endp, 10); |
| spin_lock_irq(&ts->lock); |
| |
| if (i) |
| ads7846_disable(ts); |
| else |
| ads7846_enable(ts); |
| |
| spin_unlock_irq(&ts->lock); |
| |
| return count; |
| } |
| |
| static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); |
| |
| /*--------------------------------------------------------------------------*/ |
| |
| /* |
| * PENIRQ only kicks the timer. The timer only reissues the SPI transfer, |
| * to retrieve touchscreen status. |
| * |
| * The SPI transfer completion callback does the real work. It reports |
| * touchscreen events and reactivates the timer (or IRQ) as appropriate. |
| */ |
| |
| static void ads7846_rx(void *ads) |
| { |
| struct ads7846 *ts = ads; |
| struct input_dev *input_dev = ts->input; |
| unsigned Rt; |
| unsigned sync = 0; |
| u16 x, y, z1, z2; |
| unsigned long flags; |
| |
| /* adjust: on-wire is a must-ignore bit, a BE12 value, then padding; |
| * built from two 8 bit values written msb-first. |
| */ |
| x = (be16_to_cpu(ts->tc.x) >> 3) & 0x0fff; |
| y = (be16_to_cpu(ts->tc.y) >> 3) & 0x0fff; |
| z1 = (be16_to_cpu(ts->tc.z1) >> 3) & 0x0fff; |
| z2 = (be16_to_cpu(ts->tc.z2) >> 3) & 0x0fff; |
| |
| /* range filtering */ |
| if (x == MAX_12BIT) |
| x = 0; |
| |
| if (likely(x && z1 && !device_suspended(&ts->spi->dev))) { |
| /* compute touch pressure resistance using equation #2 */ |
| Rt = z2; |
| Rt -= z1; |
| Rt *= x; |
| Rt *= ts->x_plate_ohms; |
| Rt /= z1; |
| Rt = (Rt + 2047) >> 12; |
| } else |
| Rt = 0; |
| |
| /* Sample found inconsistent by debouncing or pressure is beyond |
| * the maximum. Don't report it to user space, repeat at least |
| * once more the measurement */ |
| if (ts->tc.ignore || Rt > ts->pressure_max) { |
| mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD); |
| return; |
| } |
| |
| /* NOTE: "pendown" is inferred from pressure; we don't rely on |
| * being able to check nPENIRQ status, or "friendly" trigger modes |
| * (both-edges is much better than just-falling or low-level). |
| * |
| * REVISIT: some boards may require reading nPENIRQ; it's |
| * needed on 7843. and 7845 reads pressure differently... |
| * |
| * REVISIT: the touchscreen might not be connected; this code |
| * won't notice that, even if nPENIRQ never fires ... |
| */ |
| if (!ts->pendown && Rt != 0) { |
| input_report_key(input_dev, BTN_TOUCH, 1); |
| sync = 1; |
| } else if (ts->pendown && Rt == 0) { |
| input_report_key(input_dev, BTN_TOUCH, 0); |
| sync = 1; |
| } |
| |
| if (Rt) { |
| input_report_abs(input_dev, ABS_X, x); |
| input_report_abs(input_dev, ABS_Y, y); |
| sync = 1; |
| } |
| |
| if (sync) { |
| input_report_abs(input_dev, ABS_PRESSURE, Rt); |
| input_sync(input_dev); |
| } |
| |
| #ifdef VERBOSE |
| if (Rt || ts->pendown) |
| pr_debug("%s: %d/%d/%d%s\n", ts->spi->dev.bus_id, |
| x, y, Rt, Rt ? "" : " UP"); |
| #endif |
| |
| spin_lock_irqsave(&ts->lock, flags); |
| |
| ts->pendown = (Rt != 0); |
| mod_timer(&ts->timer, jiffies + TS_POLL_PERIOD); |
| |
| spin_unlock_irqrestore(&ts->lock, flags); |
| } |
| |
| static void ads7846_debounce(void *ads) |
| { |
| struct ads7846 *ts = ads; |
| struct spi_message *m; |
| struct spi_transfer *t; |
| int val; |
| int status; |
| |
| m = &ts->msg[ts->msg_idx]; |
| t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list); |
| val = (be16_to_cpu(*(__be16 *)t->rx_buf) >> 3) & 0x0fff; |
| if (!ts->read_cnt || (abs(ts->last_read - val) > ts->debounce_tol)) { |
| /* Repeat it, if this was the first read or the read |
| * wasn't consistent enough. */ |
| if (ts->read_cnt < ts->debounce_max) { |
| ts->last_read = val; |
| ts->read_cnt++; |
| } else { |
| /* Maximum number of debouncing reached and still |
| * not enough number of consistent readings. Abort |
| * the whole sample, repeat it in the next sampling |
| * period. |
| */ |
| ts->tc.ignore = 1; |
| ts->read_cnt = 0; |
| /* Last message will contain ads7846_rx() as the |
| * completion function. |
| */ |
| m = ts->last_msg; |
| } |
| /* Start over collecting consistent readings. */ |
| ts->read_rep = 0; |
| } else { |
| if (++ts->read_rep > ts->debounce_rep) { |
| /* Got a good reading for this coordinate, |
| * go for the next one. */ |
| ts->tc.ignore = 0; |
| ts->msg_idx++; |
| ts->read_cnt = 0; |
| ts->read_rep = 0; |
| m++; |
| } else |
| /* Read more values that are consistent. */ |
| ts->read_cnt++; |
| } |
| status = spi_async(ts->spi, m); |
| if (status) |
| dev_err(&ts->spi->dev, "spi_async --> %d\n", |
| status); |
| } |
| |
| static void ads7846_timer(unsigned long handle) |
| { |
| struct ads7846 *ts = (void *)handle; |
| int status = 0; |
| |
| spin_lock_irq(&ts->lock); |
| |
| if (unlikely(ts->msg_idx && !ts->pendown)) { |
| /* measurement cycle ended */ |
| if (!device_suspended(&ts->spi->dev)) { |
| ts->irq_disabled = 0; |
| enable_irq(ts->spi->irq); |
| } |
| ts->pending = 0; |
| ts->msg_idx = 0; |
| } else { |
| /* pen is still down, continue with the measurement */ |
| ts->msg_idx = 0; |
| status = spi_async(ts->spi, &ts->msg[0]); |
| if (status) |
| dev_err(&ts->spi->dev, "spi_async --> %d\n", status); |
| } |
| |
| spin_unlock_irq(&ts->lock); |
| } |
| |
| static irqreturn_t ads7846_irq(int irq, void *handle, struct pt_regs *regs) |
| { |
| struct ads7846 *ts = handle; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&ts->lock, flags); |
| if (likely(ts->get_pendown_state())) { |
| if (!ts->irq_disabled) { |
| /* The ARM do_simple_IRQ() dispatcher doesn't act |
| * like the other dispatchers: it will report IRQs |
| * even after they've been disabled. We work around |
| * that here. (The "generic irq" framework may help...) |
| */ |
| ts->irq_disabled = 1; |
| disable_irq(ts->spi->irq); |
| ts->pending = 1; |
| mod_timer(&ts->timer, jiffies); |
| } |
| } |
| spin_unlock_irqrestore(&ts->lock, flags); |
| |
| return IRQ_HANDLED; |
| } |
| |
| /*--------------------------------------------------------------------------*/ |
| |
| /* Must be called with ts->lock held */ |
| static void ads7846_disable(struct ads7846 *ts) |
| { |
| if (ts->disabled) |
| return; |
| |
| ts->disabled = 1; |
| |
| /* are we waiting for IRQ, or polling? */ |
| if (!ts->pending) { |
| ts->irq_disabled = 1; |
| disable_irq(ts->spi->irq); |
| } else { |
| /* the timer will run at least once more, and |
| * leave everything in a clean state, IRQ disabled |
| */ |
| while (ts->pending) { |
| spin_unlock_irq(&ts->lock); |
| msleep(1); |
| spin_lock_irq(&ts->lock); |
| } |
| } |
| |
| /* we know the chip's in lowpower mode since we always |
| * leave it that way after every request |
| */ |
| |
| } |
| |
| /* Must be called with ts->lock held */ |
| static void ads7846_enable(struct ads7846 *ts) |
| { |
| if (!ts->disabled) |
| return; |
| |
| ts->disabled = 0; |
| ts->irq_disabled = 0; |
| enable_irq(ts->spi->irq); |
| } |
| |
| static int ads7846_suspend(struct spi_device *spi, pm_message_t message) |
| { |
| struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
| |
| spin_lock_irq(&ts->lock); |
| |
| spi->dev.power.power_state = message; |
| ads7846_disable(ts); |
| |
| spin_unlock_irq(&ts->lock); |
| |
| return 0; |
| |
| } |
| |
| static int ads7846_resume(struct spi_device *spi) |
| { |
| struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
| |
| spin_lock_irq(&ts->lock); |
| |
| spi->dev.power.power_state = PMSG_ON; |
| ads7846_enable(ts); |
| |
| spin_unlock_irq(&ts->lock); |
| |
| return 0; |
| } |
| |
| static int __devinit ads7846_probe(struct spi_device *spi) |
| { |
| struct ads7846 *ts; |
| struct input_dev *input_dev; |
| struct ads7846_platform_data *pdata = spi->dev.platform_data; |
| struct spi_message *m; |
| struct spi_transfer *x; |
| int err; |
| |
| if (!spi->irq) { |
| dev_dbg(&spi->dev, "no IRQ?\n"); |
| return -ENODEV; |
| } |
| |
| if (!pdata) { |
| dev_dbg(&spi->dev, "no platform data?\n"); |
| return -ENODEV; |
| } |
| |
| /* don't exceed max specified sample rate */ |
| if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { |
| dev_dbg(&spi->dev, "f(sample) %d KHz?\n", |
| (spi->max_speed_hz/SAMPLE_BITS)/1000); |
| return -EINVAL; |
| } |
| |
| /* REVISIT when the irq can be triggered active-low, or if for some |
| * reason the touchscreen isn't hooked up, we don't need to access |
| * the pendown state. |
| */ |
| if (pdata->get_pendown_state == NULL) { |
| dev_dbg(&spi->dev, "no get_pendown_state function?\n"); |
| return -EINVAL; |
| } |
| |
| /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except |
| * that even if the hardware can do that, the SPI controller driver |
| * may not. So we stick to very-portable 8 bit words, both RX and TX. |
| */ |
| spi->bits_per_word = 8; |
| |
| ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); |
| input_dev = input_allocate_device(); |
| if (!ts || !input_dev) { |
| err = -ENOMEM; |
| goto err_free_mem; |
| } |
| |
| dev_set_drvdata(&spi->dev, ts); |
| spi->dev.power.power_state = PMSG_ON; |
| |
| ts->spi = spi; |
| ts->input = input_dev; |
| |
| init_timer(&ts->timer); |
| ts->timer.data = (unsigned long) ts; |
| ts->timer.function = ads7846_timer; |
| |
| spin_lock_init(&ts->lock); |
| |
| ts->model = pdata->model ? : 7846; |
| ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; |
| ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; |
| ts->pressure_max = pdata->pressure_max ? : ~0; |
| if (pdata->debounce_max) { |
| ts->debounce_max = pdata->debounce_max; |
| ts->debounce_tol = pdata->debounce_tol; |
| ts->debounce_rep = pdata->debounce_rep; |
| if (ts->debounce_rep > ts->debounce_max + 1) |
| ts->debounce_rep = ts->debounce_max - 1; |
| } else |
| ts->debounce_tol = ~0; |
| ts->get_pendown_state = pdata->get_pendown_state; |
| |
| snprintf(ts->phys, sizeof(ts->phys), "%s/input0", spi->dev.bus_id); |
| |
| input_dev->name = "ADS784x Touchscreen"; |
| input_dev->phys = ts->phys; |
| input_dev->cdev.dev = &spi->dev; |
| |
| input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS); |
| input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH); |
| input_set_abs_params(input_dev, ABS_X, |
| pdata->x_min ? : 0, |
| pdata->x_max ? : MAX_12BIT, |
| 0, 0); |
| input_set_abs_params(input_dev, ABS_Y, |
| pdata->y_min ? : 0, |
| pdata->y_max ? : MAX_12BIT, |
| 0, 0); |
| input_set_abs_params(input_dev, ABS_PRESSURE, |
| pdata->pressure_min, pdata->pressure_max, 0, 0); |
| |
| /* set up the transfers to read touchscreen state; this assumes we |
| * use formula #2 for pressure, not #3. |
| */ |
| m = &ts->msg[0]; |
| x = ts->xfer; |
| |
| spi_message_init(m); |
| |
| /* y- still on; turn on only y+ (and ADC) */ |
| ts->read_y = READ_Y; |
| x->tx_buf = &ts->read_y; |
| x->len = 1; |
| spi_message_add_tail(x, m); |
| |
| x++; |
| x->rx_buf = &ts->tc.y; |
| x->len = 2; |
| spi_message_add_tail(x, m); |
| |
| m->complete = ads7846_debounce; |
| m->context = ts; |
| |
| m++; |
| spi_message_init(m); |
| |
| /* turn y- off, x+ on, then leave in lowpower */ |
| x++; |
| ts->read_x = READ_X; |
| x->tx_buf = &ts->read_x; |
| x->len = 1; |
| spi_message_add_tail(x, m); |
| |
| x++; |
| x->rx_buf = &ts->tc.x; |
| x->len = 2; |
| spi_message_add_tail(x, m); |
| |
| m->complete = ads7846_debounce; |
| m->context = ts; |
| |
| /* turn y+ off, x- on; we'll use formula #2 */ |
| if (ts->model == 7846) { |
| m++; |
| spi_message_init(m); |
| |
| x++; |
| ts->read_z1 = READ_Z1; |
| x->tx_buf = &ts->read_z1; |
| x->len = 1; |
| spi_message_add_tail(x, m); |
| |
| x++; |
| x->rx_buf = &ts->tc.z1; |
| x->len = 2; |
| spi_message_add_tail(x, m); |
| |
| m->complete = ads7846_debounce; |
| m->context = ts; |
| |
| m++; |
| spi_message_init(m); |
| |
| x++; |
| ts->read_z2 = READ_Z2; |
| x->tx_buf = &ts->read_z2; |
| x->len = 1; |
| spi_message_add_tail(x, m); |
| |
| x++; |
| x->rx_buf = &ts->tc.z2; |
| x->len = 2; |
| spi_message_add_tail(x, m); |
| |
| m->complete = ads7846_debounce; |
| m->context = ts; |
| } |
| |
| /* power down */ |
| m++; |
| spi_message_init(m); |
| |
| x++; |
| ts->pwrdown = PWRDOWN; |
| x->tx_buf = &ts->pwrdown; |
| x->len = 1; |
| spi_message_add_tail(x, m); |
| |
| x++; |
| x->rx_buf = &ts->dummy; |
| x->len = 2; |
| CS_CHANGE(*x); |
| spi_message_add_tail(x, m); |
| |
| m->complete = ads7846_rx; |
| m->context = ts; |
| |
| ts->last_msg = m; |
| |
| if (request_irq(spi->irq, ads7846_irq, SA_TRIGGER_FALLING, |
| spi->dev.driver->name, ts)) { |
| dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); |
| err = -EBUSY; |
| goto err_free_mem; |
| } |
| |
| dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); |
| |
| /* take a first sample, leaving nPENIRQ active; avoid |
| * the touchscreen, in case it's not connected. |
| */ |
| (void) ads7846_read12_ser(&spi->dev, |
| READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON); |
| |
| /* ads7843/7845 don't have temperature sensors, and |
| * use the other sensors a bit differently too |
| */ |
| if (ts->model == 7846) { |
| device_create_file(&spi->dev, &dev_attr_temp0); |
| device_create_file(&spi->dev, &dev_attr_temp1); |
| } |
| if (ts->model != 7845) |
| device_create_file(&spi->dev, &dev_attr_vbatt); |
| device_create_file(&spi->dev, &dev_attr_vaux); |
| |
| device_create_file(&spi->dev, &dev_attr_pen_down); |
| |
| device_create_file(&spi->dev, &dev_attr_disable); |
| |
| err = input_register_device(input_dev); |
| if (err) |
| goto err_remove_attr; |
| |
| return 0; |
| |
| err_remove_attr: |
| device_remove_file(&spi->dev, &dev_attr_disable); |
| device_remove_file(&spi->dev, &dev_attr_pen_down); |
| if (ts->model == 7846) { |
| device_remove_file(&spi->dev, &dev_attr_temp1); |
| device_remove_file(&spi->dev, &dev_attr_temp0); |
| } |
| if (ts->model != 7845) |
| device_remove_file(&spi->dev, &dev_attr_vbatt); |
| device_remove_file(&spi->dev, &dev_attr_vaux); |
| |
| free_irq(spi->irq, ts); |
| err_free_mem: |
| input_free_device(input_dev); |
| kfree(ts); |
| return err; |
| } |
| |
| static int __devexit ads7846_remove(struct spi_device *spi) |
| { |
| struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
| |
| input_unregister_device(ts->input); |
| |
| ads7846_suspend(spi, PMSG_SUSPEND); |
| |
| device_remove_file(&spi->dev, &dev_attr_disable); |
| device_remove_file(&spi->dev, &dev_attr_pen_down); |
| if (ts->model == 7846) { |
| device_remove_file(&spi->dev, &dev_attr_temp1); |
| device_remove_file(&spi->dev, &dev_attr_temp0); |
| } |
| if (ts->model != 7845) |
| device_remove_file(&spi->dev, &dev_attr_vbatt); |
| device_remove_file(&spi->dev, &dev_attr_vaux); |
| |
| free_irq(ts->spi->irq, ts); |
| /* suspend left the IRQ disabled */ |
| enable_irq(ts->spi->irq); |
| |
| kfree(ts); |
| |
| dev_dbg(&spi->dev, "unregistered touchscreen\n"); |
| return 0; |
| } |
| |
| static struct spi_driver ads7846_driver = { |
| .driver = { |
| .name = "ads7846", |
| .bus = &spi_bus_type, |
| .owner = THIS_MODULE, |
| }, |
| .probe = ads7846_probe, |
| .remove = __devexit_p(ads7846_remove), |
| .suspend = ads7846_suspend, |
| .resume = ads7846_resume, |
| }; |
| |
| static int __init ads7846_init(void) |
| { |
| /* grr, board-specific init should stay out of drivers!! */ |
| |
| #ifdef CONFIG_ARCH_OMAP |
| if (machine_is_omap_osk()) { |
| /* GPIO4 = PENIRQ; GPIO6 = BUSY */ |
| omap_request_gpio(4); |
| omap_set_gpio_direction(4, 1); |
| omap_request_gpio(6); |
| omap_set_gpio_direction(6, 1); |
| } |
| // also TI 1510 Innovator, bitbanging through FPGA |
| // also Nokia 770 |
| // also Palm Tungsten T2 |
| #endif |
| |
| // PXA: |
| // also Dell Axim X50 |
| // also HP iPaq H191x/H192x/H415x/H435x |
| // also Intel Lubbock (additional to UCB1400; as temperature sensor) |
| // also Sharp Zaurus C7xx, C8xx (corgi/sheperd/husky) |
| |
| // Atmel at91sam9261-EK uses ads7843 |
| |
| // also various AMD Au1x00 devel boards |
| |
| return spi_register_driver(&ads7846_driver); |
| } |
| module_init(ads7846_init); |
| |
| static void __exit ads7846_exit(void) |
| { |
| spi_unregister_driver(&ads7846_driver); |
| |
| #ifdef CONFIG_ARCH_OMAP |
| if (machine_is_omap_osk()) { |
| omap_free_gpio(4); |
| omap_free_gpio(6); |
| } |
| #endif |
| |
| } |
| module_exit(ads7846_exit); |
| |
| MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); |
| MODULE_LICENSE("GPL"); |