/* * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc. * * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver * Based on: ads7846.c * * Bugs: Enter bugs at http://blackfin.uclinux.org/ * * 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; 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, see the file COPYING, or write * to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * History: * Copyright (c) 2005 David Brownell * Copyright (c) 2006 Nokia Corporation * Various changes: Imre Deak * * 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 */ #include #include #include #include #include #include #include #include #include #include #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100) #define MAX_SPI_FREQ_HZ 20000000 #define MAX_12BIT ((1<<12)-1) #define AD7877_REG_ZEROS 0 #define AD7877_REG_CTRL1 1 #define AD7877_REG_CTRL2 2 #define AD7877_REG_ALERT 3 #define AD7877_REG_AUX1HIGH 4 #define AD7877_REG_AUX1LOW 5 #define AD7877_REG_BAT1HIGH 6 #define AD7877_REG_BAT1LOW 7 #define AD7877_REG_BAT2HIGH 8 #define AD7877_REG_BAT2LOW 9 #define AD7877_REG_TEMP1HIGH 10 #define AD7877_REG_TEMP1LOW 11 #define AD7877_REG_SEQ0 12 #define AD7877_REG_SEQ1 13 #define AD7877_REG_DAC 14 #define AD7877_REG_NONE1 15 #define AD7877_REG_EXTWRITE 15 #define AD7877_REG_XPLUS 16 #define AD7877_REG_YPLUS 17 #define AD7877_REG_Z2 18 #define AD7877_REG_aux1 19 #define AD7877_REG_aux2 20 #define AD7877_REG_aux3 21 #define AD7877_REG_bat1 22 #define AD7877_REG_bat2 23 #define AD7877_REG_temp1 24 #define AD7877_REG_temp2 25 #define AD7877_REG_Z1 26 #define AD7877_REG_GPIOCTRL1 27 #define AD7877_REG_GPIOCTRL2 28 #define AD7877_REG_GPIODATA 29 #define AD7877_REG_NONE2 30 #define AD7877_REG_NONE3 31 #define AD7877_SEQ_YPLUS_BIT (1<<11) #define AD7877_SEQ_XPLUS_BIT (1<<10) #define AD7877_SEQ_Z2_BIT (1<<9) #define AD7877_SEQ_AUX1_BIT (1<<8) #define AD7877_SEQ_AUX2_BIT (1<<7) #define AD7877_SEQ_AUX3_BIT (1<<6) #define AD7877_SEQ_BAT1_BIT (1<<5) #define AD7877_SEQ_BAT2_BIT (1<<4) #define AD7877_SEQ_TEMP1_BIT (1<<3) #define AD7877_SEQ_TEMP2_BIT (1<<2) #define AD7877_SEQ_Z1_BIT (1<<1) enum { AD7877_SEQ_YPOS = 0, AD7877_SEQ_XPOS = 1, AD7877_SEQ_Z2 = 2, AD7877_SEQ_AUX1 = 3, AD7877_SEQ_AUX2 = 4, AD7877_SEQ_AUX3 = 5, AD7877_SEQ_BAT1 = 6, AD7877_SEQ_BAT2 = 7, AD7877_SEQ_TEMP1 = 8, AD7877_SEQ_TEMP2 = 9, AD7877_SEQ_Z1 = 10, AD7877_NR_SENSE = 11, }; /* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */ #define AD7877_DAC_CONF 0x1 /* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */ #define AD7877_EXTW_GPIO_3_CONF 0x1C4 #define AD7877_EXTW_GPIO_DATA 0x200 /* Control REG 2 */ #define AD7877_TMR(x) ((x & 0x3) << 0) #define AD7877_REF(x) ((x & 0x1) << 2) #define AD7877_POL(x) ((x & 0x1) << 3) #define AD7877_FCD(x) ((x & 0x3) << 4) #define AD7877_PM(x) ((x & 0x3) << 6) #define AD7877_ACQ(x) ((x & 0x3) << 8) #define AD7877_AVG(x) ((x & 0x3) << 10) /* Control REG 1 */ #define AD7877_SER (1 << 11) /* non-differential */ #define AD7877_DFR (0 << 11) /* differential */ #define AD7877_MODE_NOC (0) /* Do not convert */ #define AD7877_MODE_SCC (1) /* Single channel conversion */ #define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */ #define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */ #define AD7877_CHANADD(x) ((x&0xF)<<7) #define AD7877_READADD(x) ((x)<<2) #define AD7877_WRITEADD(x) ((x)<<12) #define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \ AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \ AD7877_READADD(AD7877_REG_ ## x)) #define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \ AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT) /* * Non-touchscreen sensors only use single-ended conversions. */ struct ser_req { u16 reset; u16 ref_on; u16 command; struct spi_message msg; struct spi_transfer xfer[6]; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. */ u16 sample ____cacheline_aligned; }; struct ad7877 { struct input_dev *input; char phys[32]; struct spi_device *spi; u16 model; u16 vref_delay_usecs; u16 x_plate_ohms; u16 pressure_max; u16 cmd_crtl1; u16 cmd_crtl2; u16 cmd_dummy; u16 dac; u8 stopacq_polarity; u8 first_conversion_delay; u8 acquisition_time; u8 averaging; u8 pen_down_acc_interval; struct spi_transfer xfer[AD7877_NR_SENSE + 2]; struct spi_message msg; struct mutex mutex; bool disabled; /* P: mutex */ bool gpio3; /* P: mutex */ bool gpio4; /* P: mutex */ spinlock_t lock; struct timer_list timer; /* P: lock */ /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. */ u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned; }; static bool gpio3; module_param(gpio3, bool, 0); MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3"); /* * ad7877_read/write are only used for initial setup and for sysfs controls. * The main traffic is done using spi_async() in the interrupt handler. */ static int ad7877_read(struct spi_device *spi, u16 reg) { struct ser_req *req; int status, ret; req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; spi_message_init(&req->msg); req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_READADD(reg)); req->xfer[0].tx_buf = &req->command; req->xfer[0].len = 2; req->xfer[0].cs_change = 1; req->xfer[1].rx_buf = &req->sample; req->xfer[1].len = 2; spi_message_add_tail(&req->xfer[0], &req->msg); spi_message_add_tail(&req->xfer[1], &req->msg); status = spi_sync(spi, &req->msg); ret = status ? : req->sample; kfree(req); return ret; } static int ad7877_write(struct spi_device *spi, u16 reg, u16 val) { struct ser_req *req; int status; req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; spi_message_init(&req->msg); req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT)); req->xfer[0].tx_buf = &req->command; req->xfer[0].len = 2; spi_message_add_tail(&req->xfer[0], &req->msg); status = spi_sync(spi, &req->msg); kfree(req); return status; } static int ad7877_read_adc(struct spi_device *spi, unsigned command) { struct ad7877 *ts = dev_get_drvdata(&spi->dev); struct ser_req *req; int status; int sample; int i; req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; spi_message_init(&req->msg); /* activate reference, so it has time to settle; */ req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) | AD7877_POL(ts->stopacq_polarity) | AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) | AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0); req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC; req->command = (u16) command; req->xfer[0].tx_buf = &req->reset; req->xfer[0].len = 2; req->xfer[0].cs_change = 1; req->xfer[1].tx_buf = &req->ref_on; req->xfer[1].len = 2; req->xfer[1].delay_usecs = ts->vref_delay_usecs; req->xfer[1].cs_change = 1; req->xfer[2].tx_buf = &req->command; req->xfer[2].len = 2; req->xfer[2].delay_usecs = ts->vref_delay_usecs; req->xfer[2].cs_change = 1; req->xfer[3].rx_buf = &req->sample; req->xfer[3].len = 2; req->xfer[3].cs_change = 1; req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/ req->xfer[4].len = 2; req->xfer[4].cs_change = 1; req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/ req->xfer[5].len = 2; /* 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); status = spi_sync(spi, &req->msg); sample = req->sample; kfree(req); return status ? : sample; } static int ad7877_process_data(struct ad7877 *ts) { struct input_dev *input_dev = ts->input; unsigned Rt; u16 x, y, z1, z2; x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT; y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT; z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT; z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT; /* * The samples processed here are already preprocessed by the AD7877. * The preprocessing function consists of an averaging filter. * The combination of 'first conversion delay' and averaging provides a robust solution, * discarding the spurious noise in the signal and keeping only the data of interest. * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h) * Other user-programmable conversion controls include variable acquisition time, * and first conversion delay. Up to 16 averages can be taken per conversion. */ if (likely(x && z1)) { /* compute touch pressure resistance using equation #1 */ Rt = (z2 - z1) * x * ts->x_plate_ohms; Rt /= z1; Rt = (Rt + 2047) >> 12; /* * Sample found inconsistent, pressure is beyond * the maximum. Don't report it to user space. */ if (Rt > ts->pressure_max) return -EINVAL; if (!timer_pending(&ts->timer)) input_report_key(input_dev, BTN_TOUCH, 1); input_report_abs(input_dev, ABS_X, x); input_report_abs(input_dev, ABS_Y, y); input_report_abs(input_dev, ABS_PRESSURE, Rt); input_sync(input_dev); return 0; } return -EINVAL; } static inline void ad7877_ts_event_release(struct ad7877 *ts) { struct input_dev *input_dev = ts->input; input_report_abs(input_dev, ABS_PRESSURE, 0); input_report_key(input_dev, BTN_TOUCH, 0); input_sync(input_dev); } static void ad7877_timer(unsigned long handle) { struct ad7877 *ts = (void *)handle; unsigned long flags; spin_lock_irqsave(&ts->lock, flags); ad7877_ts_event_release(ts); spin_unlock_irqrestore(&ts->lock, flags); } static irqreturn_t ad7877_irq(int irq, void *handle) { struct ad7877 *ts = handle; unsigned long flags; int error; error = spi_sync(ts->spi, &ts->msg); if (error) { dev_err(&ts->spi->dev, "spi_sync --> %d\n", error); goto out; } spin_lock_irqsave(&ts->lock, flags); error = ad7877_process_data(ts); if (!error) mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT); spin_unlock_irqrestore(&ts->lock, flags); out: return IRQ_HANDLED; } static void ad7877_disable(struct ad7877 *ts) { mutex_lock(&ts->mutex); if (!ts->disabled) { ts->disabled = true; disable_irq(ts->spi->irq); if (del_timer_sync(&ts->timer)) ad7877_ts_event_release(ts); } /* * We know the chip's in lowpower mode since we always * leave it that way after every request */ mutex_unlock(&ts->mutex); } static void ad7877_enable(struct ad7877 *ts) { mutex_lock(&ts->mutex); if (ts->disabled) { ts->disabled = false; enable_irq(ts->spi->irq); } mutex_unlock(&ts->mutex); } #define SHOW(name) static ssize_t \ name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ { \ struct ad7877 *ts = dev_get_drvdata(dev); \ ssize_t v = ad7877_read_adc(ts->spi, \ AD7877_READ_CHAN(name)); \ if (v < 0) \ return v; \ return sprintf(buf, "%u\n", (unsigned) v); \ } \ static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); SHOW(aux1) SHOW(aux2) SHOW(aux3) SHOW(bat1) SHOW(bat2) SHOW(temp1) SHOW(temp2) static ssize_t ad7877_disable_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ad7877 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->disabled); } static ssize_t ad7877_disable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ad7877 *ts = dev_get_drvdata(dev); unsigned long val; int error; error = strict_strtoul(buf, 10, &val); if (error) return error; if (val) ad7877_disable(ts); else ad7877_enable(ts); return count; } static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store); static ssize_t ad7877_dac_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ad7877 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->dac); } static ssize_t ad7877_dac_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ad7877 *ts = dev_get_drvdata(dev); unsigned long val; int error; error = strict_strtoul(buf, 10, &val); if (error) return error; mutex_lock(&ts->mutex); ts->dac = val & 0xFF; ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF); mutex_unlock(&ts->mutex); return count; } static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store); static ssize_t ad7877_gpio3_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ad7877 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->gpio3); } static ssize_t ad7877_gpio3_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ad7877 *ts = dev_get_drvdata(dev); unsigned long val; int error; error = strict_strtoul(buf, 10, &val); if (error) return error; mutex_lock(&ts->mutex); ts->gpio3 = !!val; ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | (ts->gpio4 << 4) | (ts->gpio3 << 5)); mutex_unlock(&ts->mutex); return count; } static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store); static ssize_t ad7877_gpio4_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ad7877 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->gpio4); } static ssize_t ad7877_gpio4_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ad7877 *ts = dev_get_drvdata(dev); unsigned long val; int error; error = strict_strtoul(buf, 10, &val); if (error) return error; mutex_lock(&ts->mutex); ts->gpio4 = !!val; ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA | (ts->gpio4 << 4) | (ts->gpio3 << 5)); mutex_unlock(&ts->mutex); return count; } static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store); static struct attribute *ad7877_attributes[] = { &dev_attr_temp1.attr, &dev_attr_temp2.attr, &dev_attr_aux1.attr, &dev_attr_aux2.attr, &dev_attr_aux3.attr, &dev_attr_bat1.attr, &dev_attr_bat2.attr, &dev_attr_disable.attr, &dev_attr_dac.attr, &dev_attr_gpio3.attr, &dev_attr_gpio4.attr, NULL }; static mode_t ad7877_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n) { mode_t mode = attr->mode; if (attr == &dev_attr_aux3.attr) { if (gpio3) mode = 0; } else if (attr == &dev_attr_gpio3.attr) { if (!gpio3) mode = 0; } return mode; } static const struct attribute_group ad7877_attr_group = { .is_visible = ad7877_attr_is_visible, .attrs = ad7877_attributes, }; static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts) { struct spi_message *m; int i; ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) | AD7877_POL(ts->stopacq_polarity) | AD7877_AVG(ts->averaging) | AD7877_PM(1) | AD7877_TMR(ts->pen_down_acc_interval) | AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(ts->first_conversion_delay); ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2); ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_READADD(AD7877_REG_XPLUS-1) | AD7877_MODE_SEQ1 | AD7877_DFR; ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1); ts->cmd_dummy = 0; m = &ts->msg; spi_message_init(m); m->context = ts; ts->xfer[0].tx_buf = &ts->cmd_crtl1; ts->xfer[0].len = 2; ts->xfer[0].cs_change = 1; spi_message_add_tail(&ts->xfer[0], m); ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */ ts->xfer[1].len = 2; ts->xfer[1].cs_change = 1; spi_message_add_tail(&ts->xfer[1], m); for (i = 0; i < AD7877_NR_SENSE; i++) { ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i]; ts->xfer[i + 2].len = 2; if (i < (AD7877_NR_SENSE - 1)) ts->xfer[i + 2].cs_change = 1; spi_message_add_tail(&ts->xfer[i + 2], m); } } static int __devinit ad7877_probe(struct spi_device *spi) { struct ad7877 *ts; struct input_dev *input_dev; struct ad7877_platform_data *pdata = spi->dev.platform_data; int err; u16 verify; 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 SPI CLK frequency */ if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) { dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz); return -EINVAL; } spi->bits_per_word = 16; err = spi_setup(spi); if (err) { dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n"); return err; } ts = kzalloc(sizeof(struct ad7877), GFP_KERNEL); input_dev = input_allocate_device(); if (!ts || !input_dev) { err = -ENOMEM; goto err_free_mem; } dev_set_drvdata(&spi->dev, ts); ts->spi = spi; ts->input = input_dev; setup_timer(&ts->timer, ad7877_timer, (unsigned long) ts); mutex_init(&ts->mutex); spin_lock_init(&ts->lock); ts->model = pdata->model ? : 7877; 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; ts->stopacq_polarity = pdata->stopacq_polarity; ts->first_conversion_delay = pdata->first_conversion_delay; ts->acquisition_time = pdata->acquisition_time; ts->averaging = pdata->averaging; ts->pen_down_acc_interval = pdata->pen_down_acc_interval; snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); input_dev->name = "AD7877 Touchscreen"; input_dev->phys = ts->phys; input_dev->dev.parent = &spi->dev; __set_bit(EV_KEY, input_dev->evbit); __set_bit(BTN_TOUCH, input_dev->keybit); __set_bit(EV_ABS, input_dev->evbit); __set_bit(ABS_X, input_dev->absbit); __set_bit(ABS_Y, input_dev->absbit); __set_bit(ABS_PRESSURE, input_dev->absbit); 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); ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE); verify = ad7877_read(spi, AD7877_REG_SEQ1); if (verify != AD7877_MM_SEQUENCE){ dev_err(&spi->dev, "%s: Failed to probe %s\n", dev_name(&spi->dev), input_dev->name); err = -ENODEV; goto err_free_mem; } if (gpio3) ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF); ad7877_setup_ts_def_msg(spi, ts); /* Request AD7877 /DAV GPIO interrupt */ err = request_threaded_irq(spi->irq, NULL, ad7877_irq, IRQF_TRIGGER_FALLING | IRQF_ONESHOT, spi->dev.driver->name, ts); if (err) { dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); goto err_free_mem; } err = sysfs_create_group(&spi->dev.kobj, &ad7877_attr_group); if (err) goto err_free_irq; err = input_register_device(input_dev); if (err) goto err_remove_attr_group; return 0; err_remove_attr_group: sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group); err_free_irq: free_irq(spi->irq, ts); err_free_mem: input_free_device(input_dev); kfree(ts); dev_set_drvdata(&spi->dev, NULL); return err; } static int __devexit ad7877_remove(struct spi_device *spi) { struct ad7877 *ts = dev_get_drvdata(&spi->dev); sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group); ad7877_disable(ts); free_irq(ts->spi->irq, ts); input_unregister_device(ts->input); kfree(ts); dev_dbg(&spi->dev, "unregistered touchscreen\n"); dev_set_drvdata(&spi->dev, NULL); return 0; } #ifdef CONFIG_PM_SLEEP static int ad7877_suspend(struct device *dev) { struct ad7877 *ts = dev_get_drvdata(dev); ad7877_disable(ts); return 0; } static int ad7877_resume(struct device *dev) { struct ad7877 *ts = dev_get_drvdata(dev); ad7877_enable(ts); return 0; } #endif static SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume); static struct spi_driver ad7877_driver = { .driver = { .name = "ad7877", .bus = &spi_bus_type, .owner = THIS_MODULE, .pm = &ad7877_pm, }, .probe = ad7877_probe, .remove = __devexit_p(ad7877_remove), }; static int __init ad7877_init(void) { return spi_register_driver(&ad7877_driver); } module_init(ad7877_init); static void __exit ad7877_exit(void) { spi_unregister_driver(&ad7877_driver); } module_exit(ad7877_exit); MODULE_AUTHOR("Michael Hennerich "); MODULE_DESCRIPTION("AD7877 touchscreen Driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("spi:ad7877");