From 7fbef0d1e278a0a8c803a4d2b1e2bd5740bffa52 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Mon, 19 Apr 2010 00:42:16 -0700 Subject: Input: eeti_ts - cancel pending work when going to suspend This fixes a race between the suspend code and input events. Signed-off-by: Daniel Mack Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/eeti_ts.c | 56 ++++++++++++++++++++++++++++++------- 1 file changed, 46 insertions(+), 10 deletions(-) (limited to 'drivers/input/touchscreen') diff --git a/drivers/input/touchscreen/eeti_ts.c b/drivers/input/touchscreen/eeti_ts.c index 9029bd3..6fb6bd8 100644 --- a/drivers/input/touchscreen/eeti_ts.c +++ b/drivers/input/touchscreen/eeti_ts.c @@ -123,14 +123,25 @@ static irqreturn_t eeti_ts_isr(int irq, void *dev_id) return IRQ_HANDLED; } -static int eeti_ts_open(struct input_dev *dev) +static void eeti_ts_start(struct eeti_ts_priv *priv) { - struct eeti_ts_priv *priv = input_get_drvdata(dev); - enable_irq(priv->irq); /* Read the events once to arm the IRQ */ eeti_ts_read(&priv->work); +} + +static void eeti_ts_stop(struct eeti_ts_priv *priv) +{ + disable_irq(priv->irq); + cancel_work_sync(&priv->work); +} + +static int eeti_ts_open(struct input_dev *dev) +{ + struct eeti_ts_priv *priv = input_get_drvdata(dev); + + eeti_ts_start(priv); return 0; } @@ -139,8 +150,7 @@ static void eeti_ts_close(struct input_dev *dev) { struct eeti_ts_priv *priv = input_get_drvdata(dev); - disable_irq(priv->irq); - cancel_work_sync(&priv->work); + eeti_ts_stop(priv); } static int __devinit eeti_ts_probe(struct i2c_client *client, @@ -152,10 +162,12 @@ static int __devinit eeti_ts_probe(struct i2c_client *client, unsigned int irq_flags; int err = -ENOMEM; - /* In contrast to what's described in the datasheet, there seems + /* + * In contrast to what's described in the datasheet, there seems * to be no way of probing the presence of that device using I2C * commands. So we need to blindly believe it is there, and wait - * for interrupts to occur. */ + * for interrupts to occur. + */ priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) { @@ -211,9 +223,11 @@ static int __devinit eeti_ts_probe(struct i2c_client *client, goto err2; } - /* Disable the irq for now. It will be enabled once the input device - * is opened. */ - disable_irq(priv->irq); + /* + * Disable the device for now. It will be enabled once the + * input device is opened. + */ + eeti_ts_stop(priv); device_init_wakeup(&client->dev, 0); return 0; @@ -234,6 +248,12 @@ static int __devexit eeti_ts_remove(struct i2c_client *client) struct eeti_ts_priv *priv = i2c_get_clientdata(client); free_irq(priv->irq, priv); + /* + * eeti_ts_stop() leaves IRQ disabled. We need to re-enable it + * so that device still works if we reload the driver. + */ + enable_irq(priv->irq); + input_unregister_device(priv->input); i2c_set_clientdata(client, NULL); kfree(priv); @@ -245,6 +265,14 @@ static int __devexit eeti_ts_remove(struct i2c_client *client) static int eeti_ts_suspend(struct i2c_client *client, pm_message_t mesg) { struct eeti_ts_priv *priv = i2c_get_clientdata(client); + struct input_dev *input_dev = priv->input; + + mutex_lock(&input_dev->mutex); + + if (input_dev->users) + eeti_ts_stop(priv); + + mutex_unlock(&input_dev->mutex); if (device_may_wakeup(&client->dev)) enable_irq_wake(priv->irq); @@ -255,10 +283,18 @@ static int eeti_ts_suspend(struct i2c_client *client, pm_message_t mesg) static int eeti_ts_resume(struct i2c_client *client) { struct eeti_ts_priv *priv = i2c_get_clientdata(client); + struct input_dev *input_dev = priv->input; if (device_may_wakeup(&client->dev)) disable_irq_wake(priv->irq); + mutex_lock(&input_dev->mutex); + + if (input_dev->users) + eeti_ts_start(priv); + + mutex_unlock(&input_dev->mutex); + return 0; } #else -- cgit v1.1 From 3843384a055496dfed3c93ae883d964d8290fdab Mon Sep 17 00:00:00 2001 From: Oskar Schirmer Date: Thu, 13 May 2010 00:42:23 -0700 Subject: Input: ad7877 - keep dma rx buffers in seperate cache lines MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With dma based spi transmission, data corruption is observed occasionally. With dma buffers located right next to msg and xfer fields, cache lines correctly flushed in preparation for dma usage may be polluted again when writing to fields in the same cache line. Make sure cache fields used with dma do not share cache lines with fields changed during dma handling. As both fields are part of a struct that is allocated via kzalloc, thus cache aligned, moving the fields to the 1st position and insert padding for alignment does the job. Signed-off-by: Oskar Schirmer Signed-off-by: Daniel Glöckner Signed-off-by: Oliver Schneidewind Signed-off-by: Johannes Weiner Acked-by: Mike Frysinger [dtor@mail.ru - changed to use ___cacheline_aligned as suggested by akpm] Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/ad7877.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/input/touchscreen') diff --git a/drivers/input/touchscreen/ad7877.c b/drivers/input/touchscreen/ad7877.c index e019d53..0d2d7e5 100644 --- a/drivers/input/touchscreen/ad7877.c +++ b/drivers/input/touchscreen/ad7877.c @@ -156,9 +156,14 @@ struct ser_req { u16 reset; u16 ref_on; u16 command; - u16 sample; 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 { @@ -182,8 +187,6 @@ struct ad7877 { u8 averaging; u8 pen_down_acc_interval; - u16 conversion_data[AD7877_NR_SENSE]; - struct spi_transfer xfer[AD7877_NR_SENSE + 2]; struct spi_message msg; @@ -195,6 +198,12 @@ struct ad7877 { spinlock_t lock; struct timer_list timer; /* P: lock */ unsigned pending:1; /* 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 int gpio3; -- cgit v1.1