From patchwork Thu Sep 2 16:01:33 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Torokhov X-Patchwork-Id: 149851 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o82G1h6v013983 for ; Thu, 2 Sep 2010 16:01:44 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756344Ab0IBQBn (ORCPT ); Thu, 2 Sep 2010 12:01:43 -0400 Received: from mail-vw0-f46.google.com ([209.85.212.46]:37835 "EHLO mail-vw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753744Ab0IBQBl (ORCPT ); Thu, 2 Sep 2010 12:01:41 -0400 Received: by vws3 with SMTP id 3so485881vws.19 for ; Thu, 02 Sep 2010 09:01:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:cc:subject :message-id:references:mime-version:content-type:content-disposition :in-reply-to:user-agent; bh=+t25zj1QGHFH/uVSqCR2R1NEvz06hm7/bdrsdG72njY=; b=AXydgpTkVglf2W7ymJ4Am1uBc1H0m8OmL+v87vj+c9Kujc/Ehgr6WLNEJnDdSstxvN vq7oYWbPcYyW3bFqpN0EVtryZCzgTSMAj9qSCqFaH5i7IKxCiEGlbXbgBDh+0qbp1TYi U8ys8XU6/jY2CVP63eG39TvKQuRYSl/kXTYOg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=BUaZl8FjVpHbVr5hHOVBIE9icEerEvyseQI/Z2M1XKmqqRBbjrCyr4kmaZOffpV2Hj lS3uEZwr0ltWHMK9JMhMjUz95igKInGDAR8eXNuwMX5XCLog5oM3FRRwWZxD7wpf9YJR 0rIihb6LuQ3wesnr4nesD2+LtUbZpRF5S7yLQ= Received: by 10.229.218.143 with SMTP id hq15mr7617110qcb.34.1283443299839; Thu, 02 Sep 2010 09:01:39 -0700 (PDT) Received: from mailhub.coreip.homeip.net (c-24-6-153-206.hsd1.ca.comcast.net [24.6.153.206]) by mx.google.com with ESMTPS id r36sm615062qcs.3.2010.09.02.09.01.36 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 02 Sep 2010 09:01:37 -0700 (PDT) Date: Thu, 2 Sep 2010 09:01:33 -0700 From: Dmitry Torokhov To: Jason Wang Cc: notasas@gmail.com, vapier@gentoo.org, linux-input@vger.kernel.org Subject: Re: [PATCH v2] Input: ads7846 - Replace spinlock by mutex to wrap disable()/enable() Message-ID: <20100902160132.GD16914@core.coreip.homeip.net> References: <1282370340-3157-1-git-send-email-jason77.wang@gmail.com> <4C7491D7.1030801@gmail.com> <20100901064841.GH23585@core.coreip.homeip.net> <4C7E25E2.90904@gmail.com> <20100901164818.GA6908@core.coreip.homeip.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20100901164818.GA6908@core.coreip.homeip.net> User-Agent: Mutt/1.5.20 (2009-12-10) Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Thu, 02 Sep 2010 16:01:44 +0000 (UTC) diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c index 1603193..d1fc8ef 100644 --- a/drivers/input/touchscreen/ads7846.c +++ b/drivers/input/touchscreen/ads7846.c @@ -17,6 +17,7 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ +#include #include #include #include @@ -52,22 +53,23 @@ * files. */ -#define TS_POLL_DELAY (1 * 1000000) /* ns delay before the first sample */ -#define TS_POLL_PERIOD (5 * 1000000) /* ns delay between samples */ +#define TS_POLL_DELAY 1 /* ms delay before the first sample */ +#define TS_POLL_PERIOD 5 /* ms delay between samples */ /* 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 + /* + * For portability, we can't read 12 bit values using SPI (which + * would make the controller deliver them as native byte order u16 * with msbs zeroed). Instead, we read them as two 8-bit values, * *** WHICH NEED BYTESWAPPING *** and range adjustment. */ u16 x; u16 y; u16 z1, z2; - int ignore; + bool ignore; u8 x_buf[3]; u8 y_buf[3]; }; @@ -110,8 +112,11 @@ struct ads7846 { struct spi_transfer xfer[18]; struct spi_message msg[5]; - struct spi_message *last_msg; - int msg_idx; + int msg_count; + wait_queue_head_t wait; + + bool pendown; + int read_cnt; int read_rep; int last_read; @@ -122,14 +127,10 @@ struct ads7846 { u16 penirq_recheck_delay_usecs; - spinlock_t lock; - struct hrtimer timer; - unsigned pendown:1; /* P: lock */ - unsigned pending:1; /* P: lock */ -// FIXME remove "irq_disabled" - unsigned irq_disabled:1; /* P: lock */ - unsigned disabled:1; - unsigned is_suspended:1; + struct mutex lock; + bool stopped; /* P: lock */ + bool disabled; /* P: lock */ + bool suspended; /* P: lock */ int (*filter)(void *data, int data_idx, int *val); void *filter_data; @@ -165,7 +166,7 @@ struct ads7846 { #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_PDOWN (0 << 0) /* low power 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 */ @@ -193,6 +194,72 @@ struct ads7846 { #define REF_ON (READ_12BIT_DFR(x, 1, 1)) #define REF_OFF (READ_12BIT_DFR(y, 0, 0)) +/* Must be called with ts->lock held */ +static void ads7846_stop(struct ads7846 *ts) +{ + if (!ts->disabled && !ts->suspended) { + /* Signal IRQ thread to stop polling and disable the handler. */ + ts->stopped = true; + mb(); + wake_up(&ts->wait); + disable_irq(ts->spi->irq); + } +} + +/* Must be called with ts->lock held */ +static void ads7846_restart(struct ads7846 *ts) +{ + if (!ts->disabled && !ts->suspended) { + /* Tell IRQ thread that it may poll the device. */ + ts->stopped = false; + mb(); + enable_irq(ts->spi->irq); + } +} + +/* Must be called with ts->lock held */ +static void __ads7846_disable(struct ads7846 *ts) +{ + ads7846_stop(ts); + regulator_disable(ts->reg); + + /* + * We know the chip's in low power 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) +{ + regulator_enable(ts->reg); + ads7846_restart(ts); +} + +static void ads7846_disable(struct ads7846 *ts) +{ + mutex_lock(&ts->lock); + + if (!ts->disabled && !ts->suspended) + __ads7846_disable(ts); + + ts->disabled = true; + + mutex_unlock(&ts->lock); +} + +static void ads7846_enable(struct ads7846 *ts) +{ + mutex_lock(&ts->lock); + + if (ts->disabled && !ts->suspended) + __ads7846_enable(ts); + + ts->disabled = false; + + mutex_unlock(&ts->lock); +} + /*--------------------------------------------------------------------------*/ /* @@ -219,23 +286,15 @@ struct ads7845_ser_req { struct spi_transfer xfer[2]; }; -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 ts->is_suspended || 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, GFP_KERNEL); - int status; - int use_internal; + struct spi_device *spi = to_spi_device(dev); + struct ads7846 *ts = dev_get_drvdata(dev); + struct ser_req *req; + int status; + int use_internal; + req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; @@ -282,11 +341,11 @@ static int ads7846_read12_ser(struct device *dev, unsigned command) CS_CHANGE(req->xfer[5]); spi_message_add_tail(&req->xfer[5], &req->msg); - ts->irq_disabled = 1; - disable_irq(spi->irq); + mutex_lock(&ts->lock); + ads7846_stop(ts); status = spi_sync(spi, &req->msg); - ts->irq_disabled = 0; - enable_irq(spi->irq); + ads7846_restart(ts); + mutex_unlock(&ts->lock); if (status == 0) { /* on-wire is a must-ignore bit, a BE12 value, then padding */ @@ -301,11 +360,12 @@ static int ads7846_read12_ser(struct device *dev, unsigned command) static int ads7845_read12_ser(struct device *dev, unsigned command) { - struct spi_device *spi = to_spi_device(dev); - struct ads7846 *ts = dev_get_drvdata(dev); - struct ads7845_ser_req *req = kzalloc(sizeof *req, GFP_KERNEL); - int status; + struct spi_device *spi = to_spi_device(dev); + struct ads7846 *ts = dev_get_drvdata(dev); + struct ads7845_ser_req *req; + int status; + req = kzalloc(sizeof *req, GFP_KERNEL); if (!req) return -ENOMEM; @@ -317,11 +377,11 @@ static int ads7845_read12_ser(struct device *dev, unsigned command) req->xfer[0].len = 3; spi_message_add_tail(&req->xfer[0], &req->msg); - ts->irq_disabled = 1; - disable_irq(spi->irq); + mutex_lock(&ts->lock); + ads7846_stop(ts); status = spi_sync(spi, &req->msg); - ts->irq_disabled = 0; - enable_irq(spi->irq); + ads7846_restart(ts); + mutex_unlock(&ts->lock); if (status == 0) { /* BE12 value, then padding */ @@ -374,6 +434,7 @@ static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) /* external resistors may scale vAUX into 0..vREF */ retval *= ts->vref_mv; retval = retval >> 12; + return retval; } @@ -384,13 +445,13 @@ static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) /* ads7846 has a resistor ladder to scale this signal down */ if (ts->model == 7846) retval *= 4; + return retval; } SHOW(in0_input, vaux, vaux_adjust) SHOW(in1_input, vbatt, vbatt_adjust) - static struct attribute *ads7846_attributes[] = { &dev_attr_temp0.attr, &dev_attr_temp1.attr, @@ -498,17 +559,12 @@ static inline void ads784x_hwmon_unregister(struct spi_device *spi, } #endif -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)); + struct ads7846 *ts = dev_get_drvdata(dev); + + return sprintf(buf, "%u\n", ts->pendown); } static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); @@ -516,7 +572,7 @@ 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); + struct ads7846 *ts = dev_get_drvdata(dev); return sprintf(buf, "%u\n", ts->disabled); } @@ -531,15 +587,11 @@ static ssize_t ads7846_disable_store(struct device *dev, if (strict_strtoul(buf, 10, &i)) return -EINVAL; - spin_lock_irq(&ts->lock); - if (i) ads7846_disable(ts); else ads7846_enable(ts); - spin_unlock_irq(&ts->lock); - return count; } @@ -569,23 +621,138 @@ static void null_wait_for_sync(void) { } -/* - * 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 int ads7846_debounce_filter(void *ads, int data_idx, int *val) +{ + struct ads7846 *ts = ads; + + if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { + /* Start over collecting consistent readings. */ + ts->read_rep = 0; + /* + * 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++; + return ADS7846_FILTER_REPEAT; + } 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->read_cnt = 0; + return ADS7846_FILTER_IGNORE; + } + } else { + if (++ts->read_rep > ts->debounce_rep) { + /* + * Got a good reading for this coordinate, + * go for the next one. + */ + ts->read_cnt = 0; + ts->read_rep = 0; + return ADS7846_FILTER_OK; + } else { + /* Read more values that are consistent. */ + ts->read_cnt++; + return ADS7846_FILTER_REPEAT; + } + } +} + +static int ads7846_no_filter(void *ads, int data_idx, int *val) +{ + return ADS7846_FILTER_OK; +} + +static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) +{ + struct spi_transfer *t = + list_entry(m->transfers.prev, struct spi_transfer, transfer_list); + + if (ts->model == 7845) { + return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; + } else { + /* + * adjust: on-wire is a must-ignore bit, a BE12 value, then + * padding; built from two 8 bit values written msb-first. + */ + return be16_to_cpup((__be16 *)t->rx_buf) >> 3; + } +} + +static void ads7846_update_value(struct spi_message *m, int val) +{ + struct spi_transfer *t = + list_entry(m->transfers.prev, struct spi_transfer, transfer_list); + + *(u16 *)t->rx_buf = val; +} + +static void ads7846_read_state(struct ads7846 *ts) +{ + struct ads7846_packet *packet = ts->packet; + struct spi_message *m; + int msg_idx = 0; + int val; + int action; + int error; + + while (msg_idx < ts->msg_count) { + + ts->wait_for_sync(); + + m = &ts->msg[msg_idx]; + error = spi_sync(ts->spi, m); + if (error) { + dev_err(&ts->spi->dev, "spi_async --> %d\n", error); + packet->tc.ignore = true; + return; + } + + /* + * Last message is power down request, no need to convert + * or filter the value. + */ + if (msg_idx < ts->msg_count - 1) { + + val = ads7846_get_value(ts, m); + + action = ts->filter(ts->filter_data, msg_idx, &val); + switch (action) { + case ADS7846_FILTER_REPEAT: + continue; + + case ADS7846_FILTER_IGNORE: + packet->tc.ignore = true; + return; -static void ads7846_rx(void *ads) + case ADS7846_FILTER_OK: + ads7846_update_value(m, val); + packet->tc.ignore = false; + msg_idx++; + break; + + default: + BUG(); + } + } + } +} + +static void ads7846_report_state(struct ads7846 *ts) { - struct ads7846 *ts = ads; - struct ads7846_packet *packet = ts->packet; - unsigned Rt; - u16 x, y, z1, z2; + struct ads7846_packet *packet = ts->packet; + unsigned int Rt; + u16 x, y, z1, z2; - /* ads7846_rx_val() did in-place conversion (including byteswap) from - * on-the-wire format as part of debouncing to get stable readings. + /* + * ads7846_get_value() does in-place conversion (including byte swap) + * from on-the-wire format as part of debouncing to get stable + * readings. */ if (ts->model == 7845) { x = *(u16 *)packet->tc.x_buf; @@ -623,19 +790,19 @@ static void ads7846_rx(void *ads) Rt = 0; } - /* Sample found inconsistent by debouncing or pressure is beyond + /* + * 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 (packet->tc.ignore || Rt > ts->pressure_max) { dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", packet->tc.ignore, Rt); - hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), - HRTIMER_MODE_REL); return; } - /* Maybe check the pendown state before reporting. This discards + /* + * Maybe check the pendown state before reporting. This discards * false readings when the pen is lifted. */ if (ts->penirq_recheck_delay_usecs) { @@ -644,8 +811,9 @@ static void ads7846_rx(void *ads) Rt = 0; } - /* NOTE: We can't rely on the pressure to determine the pen down - * state, even this controller has a pressure sensor. The pressure + /* + * NOTE: We can't rely on the pressure to determine the pen down + * state, even this controller has a pressure sensor. The pressure * value can fluctuate for quite a while after lifting the pen and * in some cases may not even settle at the expected value. * @@ -655,15 +823,15 @@ static void ads7846_rx(void *ads) if (Rt) { struct input_dev *input = ts->input; + if (ts->swap_xy) + swap(x, y); + if (!ts->pendown) { input_report_key(input, BTN_TOUCH, 1); - ts->pendown = 1; + ts->pendown = true; dev_vdbg(&ts->spi->dev, "DOWN\n"); } - if (ts->swap_xy) - swap(x, y); - input_report_abs(input, ABS_X, x); input_report_abs(input, ABS_Y, y); input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); @@ -671,246 +839,94 @@ static void ads7846_rx(void *ads) input_sync(input); dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); } - - hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), - HRTIMER_MODE_REL); } -static int ads7846_debounce(void *ads, int data_idx, int *val) +static irqreturn_t ads7846_hard_irq(int irq, void *handle) { - struct ads7846 *ts = ads; - - if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { - /* Start over collecting consistent readings. */ - ts->read_rep = 0; - /* 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++; - return ADS7846_FILTER_REPEAT; - } 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->read_cnt = 0; - return ADS7846_FILTER_IGNORE; - } - } else { - if (++ts->read_rep > ts->debounce_rep) { - /* Got a good reading for this coordinate, - * go for the next one. */ - ts->read_cnt = 0; - ts->read_rep = 0; - return ADS7846_FILTER_OK; - } else { - /* Read more values that are consistent. */ - ts->read_cnt++; - return ADS7846_FILTER_REPEAT; - } - } -} - -static int ads7846_no_filter(void *ads, int data_idx, int *val) -{ - return ADS7846_FILTER_OK; -} - -static void ads7846_rx_val(void *ads) -{ - struct ads7846 *ts = ads; - struct ads7846_packet *packet = ts->packet; - struct spi_message *m; - struct spi_transfer *t; - int val; - int action; - int status; - - m = &ts->msg[ts->msg_idx]; - t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list); - - if (ts->model == 7845) { - val = be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; - } else { - /* adjust: on-wire is a must-ignore bit, a BE12 value, then - * padding; built from two 8 bit values written msb-first. - */ - val = be16_to_cpup((__be16 *)t->rx_buf) >> 3; - } + struct ads7846 *ts = handle; - action = ts->filter(ts->filter_data, ts->msg_idx, &val); - switch (action) { - case ADS7846_FILTER_REPEAT: - break; - case ADS7846_FILTER_IGNORE: - packet->tc.ignore = 1; - /* Last message will contain ads7846_rx() as the - * completion function. - */ - m = ts->last_msg; - break; - case ADS7846_FILTER_OK: - *(u16 *)t->rx_buf = val; - packet->tc.ignore = 0; - m = &ts->msg[++ts->msg_idx]; - break; - default: - BUG(); - } - ts->wait_for_sync(); - status = spi_async(ts->spi, m); - if (status) - dev_err(&ts->spi->dev, "spi_async --> %d\n", - status); + return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; } -static enum hrtimer_restart ads7846_timer(struct hrtimer *handle) -{ - struct ads7846 *ts = container_of(handle, struct ads7846, timer); - int status = 0; - - spin_lock(&ts->lock); - - if (unlikely(!get_pendown_state(ts) || - device_suspended(&ts->spi->dev))) { - if (ts->pendown) { - struct input_dev *input = ts->input; - - input_report_key(input, BTN_TOUCH, 0); - input_report_abs(input, ABS_PRESSURE, 0); - input_sync(input); - - ts->pendown = 0; - dev_vdbg(&ts->spi->dev, "UP\n"); - } - - /* measurement cycle ended */ - if (!device_suspended(&ts->spi->dev)) { - ts->irq_disabled = 0; - enable_irq(ts->spi->irq); - } - ts->pending = 0; - } else { - /* pen is still down, continue with the measurement */ - ts->msg_idx = 0; - ts->wait_for_sync(); - status = spi_async(ts->spi, &ts->msg[0]); - if (status) - dev_err(&ts->spi->dev, "spi_async --> %d\n", status); - } - - spin_unlock(&ts->lock); - return HRTIMER_NORESTART; -} static irqreturn_t ads7846_irq(int irq, void *handle) { struct ads7846 *ts = handle; - unsigned long flags; - - spin_lock_irqsave(&ts->lock, flags); - if (likely(get_pendown_state(ts))) { - 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_nosync(ts->spi->irq); - ts->pending = 1; - hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY), - HRTIMER_MODE_REL); - } - } - spin_unlock_irqrestore(&ts->lock, flags); - return IRQ_HANDLED; -} + /* Start with a small delay before checking pendown state */ + msleep(TS_POLL_DELAY); -/*--------------------------------------------------------------------------*/ + while (!ts->stopped && get_pendown_state(ts)) { -/* Must be called with ts->lock held */ -static void ads7846_disable(struct ads7846 *ts) -{ - if (ts->disabled) - return; + /* pen is down, continue with the measurement */ + ads7846_read_state(ts); - ts->disabled = 1; + if (!ts->stopped) + ads7846_report_state(ts); - /* 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); - } + wait_event_timeout(ts->wait, ts->stopped, + msecs_to_jiffies(TS_POLL_PERIOD)); } - regulator_disable(ts->reg); - - /* we know the chip's in lowpower mode since we always - * leave it that way after every request - */ -} + if (ts->pendown) { + struct input_dev *input = ts->input; -/* Must be called with ts->lock held */ -static void ads7846_enable(struct ads7846 *ts) -{ - if (!ts->disabled) - return; + input_report_key(input, BTN_TOUCH, 0); + input_report_abs(input, ABS_PRESSURE, 0); + input_sync(input); - regulator_enable(ts->reg); + ts->pendown = false; + dev_vdbg(&ts->spi->dev, "UP\n"); + } - ts->disabled = 0; - ts->irq_disabled = 0; - enable_irq(ts->spi->irq); + return IRQ_HANDLED; } 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); + mutex_lock(&ts->lock); - ts->is_suspended = 1; - ads7846_disable(ts); + if (!ts->suspended) { - spin_unlock_irq(&ts->lock); + if (!ts->disabled) + __ads7846_disable(ts); - if (device_may_wakeup(&ts->spi->dev)) - enable_irq_wake(ts->spi->irq); + if (device_may_wakeup(&ts->spi->dev)) + enable_irq_wake(ts->spi->irq); - return 0; + ts->suspended = true; + } + + mutex_unlock(&ts->lock); + return 0; } static int ads7846_resume(struct spi_device *spi) { struct ads7846 *ts = dev_get_drvdata(&spi->dev); - if (device_may_wakeup(&ts->spi->dev)) - disable_irq_wake(ts->spi->irq); + mutex_lock(&ts->lock); - spin_lock_irq(&ts->lock); + if (ts->suspended) { - ts->is_suspended = 0; - ads7846_enable(ts); + if (device_may_wakeup(&ts->spi->dev)) + disable_irq_wake(ts->spi->irq); - spin_unlock_irq(&ts->lock); + if (!ts->disabled) + __ads7846_enable(ts); + + ts->suspended = false; + } + + mutex_unlock(&ts->lock); return 0; } -static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts) +static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads7846 *ts) { struct ads7846_platform_data *pdata = spi->dev.platform_data; int err; @@ -932,146 +948,40 @@ static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts) err = gpio_request(pdata->gpio_pendown, "ads7846_pendown"); if (err) { dev_err(&spi->dev, "failed to request pendown GPIO%d\n", - pdata->gpio_pendown); + pdata->gpio_pendown); return err; } ts->gpio_pendown = pdata->gpio_pendown; + return 0; } -static int __devinit ads7846_probe(struct spi_device *spi) +/* + * Set up the transfers to read touchscreen state; this assumes we + * use formula #2 for pressure, not #3. + */ +static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts, + const struct ads7846_platform_data *pdata) { - struct ads7846 *ts; - struct ads7846_packet *packet; - struct input_dev *input_dev; - const struct ads7846_platform_data *pdata = spi->dev.platform_data; - struct spi_message *m; - struct spi_transfer *x; - unsigned long irq_flags; - int vref; - 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; - } - - /* 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; - spi->mode = SPI_MODE_0; - err = spi_setup(spi); - if (err < 0) - return err; - - ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); - packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); - input_dev = input_allocate_device(); - if (!ts || !packet || !input_dev) { - err = -ENOMEM; - goto err_free_mem; - } - - dev_set_drvdata(&spi->dev, ts); - - ts->packet = packet; - ts->spi = spi; - ts->input = input_dev; - ts->vref_mv = pdata->vref_mv; - ts->swap_xy = pdata->swap_xy; - - hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - 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->filter != NULL) { - if (pdata->filter_init != NULL) { - err = pdata->filter_init(pdata, &ts->filter_data); - if (err < 0) - goto err_free_mem; - } - ts->filter = pdata->filter; - ts->filter_cleanup = pdata->filter_cleanup; - } else if (pdata->debounce_max) { - ts->debounce_max = pdata->debounce_max; - if (ts->debounce_max < 2) - ts->debounce_max = 2; - ts->debounce_tol = pdata->debounce_tol; - ts->debounce_rep = pdata->debounce_rep; - ts->filter = ads7846_debounce; - ts->filter_data = ts; - } else - ts->filter = ads7846_no_filter; - - err = setup_pendown(spi, ts); - if (err) - goto err_cleanup_filter; - - if (pdata->penirq_recheck_delay_usecs) - ts->penirq_recheck_delay_usecs = - pdata->penirq_recheck_delay_usecs; - - ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; - - snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); - snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); - - input_dev->name = ts->name; - input_dev->phys = ts->phys; - input_dev->dev.parent = &spi->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, - 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); - - vref = pdata->keep_vref_on; + struct spi_message *m = &ts->msg[0]; + struct spi_transfer *x = ts->xfer; + struct ads7846_packet *packet = ts->packet; + int vref = pdata->keep_vref_on; if (ts->model == 7873) { - /* The AD7873 is almost identical to the ADS7846 + /* + * The AD7873 is almost identical to the ADS7846 * keep VREF off during differential/ratiometric - * conversion modes + * conversion modes. */ ts->model = 7846; vref = 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; - + ts->msg_count = 1; spi_message_init(m); + m->context = ts; if (ts->model == 7845) { packet->read_y_cmd[0] = READ_Y(vref); @@ -1094,7 +1004,8 @@ static int __devinit ads7846_probe(struct spi_device *spi) spi_message_add_tail(x, m); } - /* the first sample after switching drivers can be low quality; + /* + * The first sample after switching drivers can be low quality; * optionally discard it, using a second one after the signals * have had enough time to stabilize. */ @@ -1112,11 +1023,10 @@ static int __devinit ads7846_probe(struct spi_device *spi) spi_message_add_tail(x, m); } - m->complete = ads7846_rx_val; - m->context = ts; - + ts->msg_count++; m++; spi_message_init(m); + m->context = ts; if (ts->model == 7845) { x++; @@ -1156,13 +1066,12 @@ static int __devinit ads7846_probe(struct spi_device *spi) spi_message_add_tail(x, m); } - m->complete = ads7846_rx_val; - m->context = ts; - /* turn y+ off, x- on; we'll use formula #2 */ if (ts->model == 7846) { + ts->msg_count++; m++; spi_message_init(m); + m->context = ts; x++; packet->read_z1 = READ_Z1(vref); @@ -1190,11 +1099,10 @@ static int __devinit ads7846_probe(struct spi_device *spi) spi_message_add_tail(x, m); } - m->complete = ads7846_rx_val; - m->context = ts; - + ts->msg_count++; m++; spi_message_init(m); + m->context = ts; x++; packet->read_z2 = READ_Z2(vref); @@ -1221,14 +1129,13 @@ static int __devinit ads7846_probe(struct spi_device *spi) x->len = 2; spi_message_add_tail(x, m); } - - m->complete = ads7846_rx_val; - m->context = ts; } /* power down */ + ts->msg_count++; m++; spi_message_init(m); + m->context = ts; if (ts->model == 7845) { x++; @@ -1251,11 +1158,119 @@ static int __devinit ads7846_probe(struct spi_device *spi) CS_CHANGE(*x); spi_message_add_tail(x, m); +} - m->complete = ads7846_rx; - m->context = ts; +static int __devinit ads7846_probe(struct spi_device *spi) +{ + struct ads7846 *ts; + struct ads7846_packet *packet; + struct input_dev *input_dev; + struct ads7846_platform_data *pdata = spi->dev.platform_data; + unsigned long irq_flags; + int err; - ts->last_msg = m; + 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; + } + + /* We'd set TX word size 8 bits and RX word size 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; + spi->mode = SPI_MODE_0; + err = spi_setup(spi); + if (err < 0) + return err; + + ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); + packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); + input_dev = input_allocate_device(); + if (!ts || !packet || !input_dev) { + err = -ENOMEM; + goto err_free_mem; + } + + dev_set_drvdata(&spi->dev, ts); + + ts->packet = packet; + ts->spi = spi; + ts->input = input_dev; + ts->vref_mv = pdata->vref_mv; + ts->swap_xy = pdata->swap_xy; + + mutex_init(&ts->lock); + init_waitqueue_head(&ts->wait); + + 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->filter != NULL) { + if (pdata->filter_init != NULL) { + err = pdata->filter_init(pdata, &ts->filter_data); + if (err < 0) + goto err_free_mem; + } + ts->filter = pdata->filter; + ts->filter_cleanup = pdata->filter_cleanup; + } else if (pdata->debounce_max) { + ts->debounce_max = pdata->debounce_max; + if (ts->debounce_max < 2) + ts->debounce_max = 2; + ts->debounce_tol = pdata->debounce_tol; + ts->debounce_rep = pdata->debounce_rep; + ts->filter = ads7846_debounce_filter; + ts->filter_data = ts; + } else { + ts->filter = ads7846_no_filter; + } + + err = ads7846_setup_pendown(spi, ts); + if (err) + goto err_cleanup_filter; + + if (pdata->penirq_recheck_delay_usecs) + ts->penirq_recheck_delay_usecs = + pdata->penirq_recheck_delay_usecs; + + ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; + + snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); + snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); + + input_dev->name = ts->name; + input_dev->phys = ts->phys; + input_dev->dev.parent = &spi->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, + 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); + + ads7846_setup_spi_msg(ts, pdata); ts->reg = regulator_get(&spi->dev, "vcc"); if (IS_ERR(ts->reg)) { @@ -1271,16 +1286,17 @@ static int __devinit ads7846_probe(struct spi_device *spi) } irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; + irq_flags |= IRQF_ONESHOT; - err = request_irq(spi->irq, ads7846_irq, irq_flags, - spi->dev.driver->name, ts); - + err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, + irq_flags, spi->dev.driver->name, ts); if (err && !pdata->irq_flags) { dev_info(&spi->dev, "trying pin change workaround on irq %d\n", spi->irq); - err = request_irq(spi->irq, ads7846_irq, - IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, - spi->dev.driver->name, ts); + irq_flags |= IRQF_TRIGGER_RISING; + err = request_threaded_irq(spi->irq, + ads7846_hard_irq, ads7846_irq, + irq_flags, spi->dev.driver->name, ts); } if (err) { @@ -1294,7 +1310,8 @@ static int __devinit ads7846_probe(struct spi_device *spi) dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); - /* take a first sample, leaving nPENIRQ active and vREF off; avoid + /* + * Take a first sample, leaving nPENIRQ active and vREF off; avoid * the touchscreen, in case it's not connected. */ if (ts->model == 7845) @@ -1340,20 +1357,18 @@ static int __devinit ads7846_probe(struct spi_device *spi) static int __devexit ads7846_remove(struct spi_device *spi) { - struct ads7846 *ts = dev_get_drvdata(&spi->dev); + struct ads7846 *ts = dev_get_drvdata(&spi->dev); device_init_wakeup(&spi->dev, false); - ads784x_hwmon_unregister(spi, ts); - input_unregister_device(ts->input); - - ads7846_suspend(spi, PMSG_SUSPEND); - sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); + ads7846_disable(ts); free_irq(ts->spi->irq, ts); - /* suspend left the IRQ disabled */ - enable_irq(ts->spi->irq); + + input_unregister_device(ts->input); + + ads784x_hwmon_unregister(spi, ts); regulator_disable(ts->reg); regulator_put(ts->reg); @@ -1368,6 +1383,7 @@ static int __devexit ads7846_remove(struct spi_device *spi) kfree(ts); dev_dbg(&spi->dev, "unregistered touchscreen\n"); + return 0; }