[2/5,input] add mc13783 touchscreen driver
diff mbox

Message ID 1250089531-10399-3-git-send-email-s.hauer@pengutronix.de
State Changes Requested
Headers show

Commit Message

Sascha Hauer Aug. 12, 2009, 3:05 p.m. UTC
This driver provides support for the touchscreen interface
integrated into the Freescale MC13783.

changes since v1:

- remove unused functions
- use queue_delayed_work instead of queue_work
- report pen events as BTN_TOUCH instead of ABS_PRESSURE
- handle interrupt registration in open/close functions
- do not call input_free_device() on already registered
  input_device
- use platform_driver_probe instead of platform_driver_register
- add MODULE_ALIAS

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: linux-input@vger.kernel.org
---
 drivers/input/touchscreen/Kconfig      |   12 ++
 drivers/input/touchscreen/Makefile     |    1 +
 drivers/input/touchscreen/mc13783_ts.c |  222 ++++++++++++++++++++++++++++++++
 3 files changed, 235 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/touchscreen/mc13783_ts.c

Comments

Dmitry Torokhov Aug. 12, 2009, 4:04 p.m. UTC | #1
On Wed, Aug 12, 2009 at 05:05:28PM +0200, Sascha Hauer wrote:
> This driver provides support for the touchscreen interface
> integrated into the Freescale MC13783.
> 
> changes since v1:
> 
> - remove unused functions
> - use queue_delayed_work instead of queue_work
> - report pen events as BTN_TOUCH instead of ABS_PRESSURE
> - handle interrupt registration in open/close functions
> - do not call input_free_device() on already registered
>   input_device
> - use platform_driver_probe instead of platform_driver_register

BTW, if you are using platform_driver_probe() then __init is OK for
.probe() because all probes will only be run once, when driver loads.
IIRC the ability to discard probe() code was the main reason for
introducing platform_driver_probe().

> +
> +	/* unmask the ts wakeup interrupt */
> +	mc13783_set_bits(priv->mc13783, MC13783_REG_INTERRUPT_MASK_0,
> +			MC13783_INT_MASK_TSM, 0);
> +
> +	mc13783_adc_set_ts_status(priv->mc13783, 1);
> +

I actually expected these bits to go into ->open(); not the request IRQ
stuff...
Sascha Hauer Aug. 13, 2009, 12:26 p.m. UTC | #2
On Wed, Aug 12, 2009 at 09:04:38AM -0700, Dmitry Torokhov wrote:
> On Wed, Aug 12, 2009 at 05:05:28PM +0200, Sascha Hauer wrote:
> > This driver provides support for the touchscreen interface
> > integrated into the Freescale MC13783.
> > 
> > changes since v1:
> > 
> > - remove unused functions
> > - use queue_delayed_work instead of queue_work
> > - report pen events as BTN_TOUCH instead of ABS_PRESSURE
> > - handle interrupt registration in open/close functions
> > - do not call input_free_device() on already registered
> >   input_device
> > - use platform_driver_probe instead of platform_driver_register
> 
> BTW, if you are using platform_driver_probe() then __init is OK for
> .probe() because all probes will only be run once, when driver loads.
> IIRC the ability to discard probe() code was the main reason for
> introducing platform_driver_probe().

But __devinit should be ok also, right?

> 
> > +
> > +	/* unmask the ts wakeup interrupt */
> > +	mc13783_set_bits(priv->mc13783, MC13783_REG_INTERRUPT_MASK_0,
> > +			MC13783_INT_MASK_TSM, 0);
> > +
> > +	mc13783_adc_set_ts_status(priv->mc13783, 1);
> > +
> 
> I actually expected these bits to go into ->open(); not the request IRQ
> stuff...

Yes I know, I just found it convenient to request the interrupts there
so that we do not risk getting interrupts nobody is interested in this
moment.

Sascha
Dmitry Torokhov Aug. 13, 2009, 3:52 p.m. UTC | #3
On Thu, Aug 13, 2009 at 02:26:48PM +0200, Sascha Hauer wrote:
> On Wed, Aug 12, 2009 at 09:04:38AM -0700, Dmitry Torokhov wrote:
> > On Wed, Aug 12, 2009 at 05:05:28PM +0200, Sascha Hauer wrote:
> > > This driver provides support for the touchscreen interface
> > > integrated into the Freescale MC13783.
> > > 
> > > changes since v1:
> > > 
> > > - remove unused functions
> > > - use queue_delayed_work instead of queue_work
> > > - report pen events as BTN_TOUCH instead of ABS_PRESSURE
> > > - handle interrupt registration in open/close functions
> > > - do not call input_free_device() on already registered
> > >   input_device
> > > - use platform_driver_probe instead of platform_driver_register
> > 
> > BTW, if you are using platform_driver_probe() then __init is OK for
> > .probe() because all probes will only be run once, when driver loads.
> > IIRC the ability to discard probe() code was the main reason for
> > introducing platform_driver_probe().
> 
> But __devinit should be ok also, right?
> 

It is OK but then what is the point of using platform_driver_probe()
instead of platform_driver_register()? The only reason you'd want to use
platform_driver_probe() if you wanted to discard the probe methods but
it will not happen if the are marked __devinit.

> > 
> > > +
> > > +	/* unmask the ts wakeup interrupt */
> > > +	mc13783_set_bits(priv->mc13783, MC13783_REG_INTERRUPT_MASK_0,
> > > +			MC13783_INT_MASK_TSM, 0);
> > > +
> > > +	mc13783_adc_set_ts_status(priv->mc13783, 1);
> > > +
> > 
> > I actually expected these bits to go into ->open(); not the request IRQ
> > stuff...
> 
> Yes I know, I just found it convenient to request the interrupts there
> so that we do not risk getting interrupts nobody is interested in this
> moment.
> 

OK, but still, the bits above should be moved to open() as well, right?

Patch
diff mbox

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 72e2712..7451cf0 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -413,6 +413,18 @@  config TOUCHSCREEN_USB_COMPOSITE
 	  To compile this driver as a module, choose M here: the
 	  module will be called usbtouchscreen.
 
+config TOUCHSCREEN_MC13783
+	tristate "Freescale MC13783 touchscreen input driver"
+	depends on MFD_MC13783
+	help
+	  Say Y here if you have an Freescale MC13783 PMIC on your
+	  board and want to use its touchscreen
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mxc_ts.
+
 config TOUCHSCREEN_USB_EGALAX
 	default y
 	bool "eGalax, eTurboTouch CT-410/510/700 device support" if EMBEDDED
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 3e1c5e0..7b79598 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -20,6 +20,7 @@  obj-$(CONFIG_TOUCHSCREEN_INEXIO)	+= inexio.o
 obj-$(CONFIG_TOUCHSCREEN_MIGOR)		+= migor_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MTOUCH)	+= mtouch.o
 obj-$(CONFIG_TOUCHSCREEN_MK712)		+= mk712.o
+obj-$(CONFIG_TOUCHSCREEN_MC13783)	+= mc13783_ts.o
 obj-$(CONFIG_TOUCHSCREEN_HP600)		+= hp680_ts_input.o
 obj-$(CONFIG_TOUCHSCREEN_HP7XX)		+= jornada720_ts.o
 obj-$(CONFIG_TOUCHSCREEN_HTCPEN)	+= htcpen.o
diff --git a/drivers/input/touchscreen/mc13783_ts.c b/drivers/input/touchscreen/mc13783_ts.c
new file mode 100644
index 0000000..80163f1
--- /dev/null
+++ b/drivers/input/touchscreen/mc13783_ts.c
@@ -0,0 +1,222 @@ 
+/*
+ * Driver for the Freescale Semiconductor MC13783 touchscreen.
+ *
+ * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2009 Sascha Hauer, Pengutronix
+ *
+ * Initial development of this code was funded by
+ * Phytec Messtechnik GmbH, http://www.phytec.de
+ *
+ * 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, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#include <linux/mfd/mc13783-private.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/mc13783.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+
+#define MC13783_TS_NAME	"mc13783-ts"
+
+struct mc13783_ts_priv {
+	struct input_dev *idev;
+	struct mc13783 *mc13783;
+	struct delayed_work work;
+	struct workqueue_struct *workq;
+	unsigned int sample[4];
+};
+
+#define TS_MIN 1
+#define TS_MAX 1000
+
+static void mc13783_ts_handler(int irq, void *data)
+{
+	struct mc13783_ts_priv *priv = data;
+	unsigned int sts;
+
+	mc13783_reg_read(priv->mc13783, MC13783_REG_INTERRUPT_STATUS_0, &sts);
+	mc13783_reg_write(priv->mc13783, MC13783_REG_INTERRUPT_STATUS_0,
+			sts & MC13783_INT_STAT_TSI);
+
+	if (sts & MC13783_INT_STAT_TSI)
+		queue_delayed_work(priv->workq, &priv->work, 0);
+}
+
+static void mc13783_ts_report_sample(struct mc13783_ts_priv *priv)
+{
+	int x, y, press = 0;
+
+	x = (priv->sample[2] >> 2) & 0x3ff;
+	y = (priv->sample[3] >> 2) & 0x3ff;
+
+	pr_debug("mc13783_ts: x: %d y: %d\n", x, y);
+
+	if (x > TS_MIN && x < TS_MAX && y > TS_MIN && y < TS_MAX) {
+		press = 1;
+		input_report_abs(priv->idev, ABS_X, x);
+		input_report_abs(priv->idev, ABS_Y, y);
+
+		queue_delayed_work(priv->workq, &priv->work, HZ / 50);
+	}
+
+	input_report_key(priv->idev, BTN_TOUCH, press);
+	input_sync(priv->idev);
+}
+
+static void mc13783_ts_work(struct work_struct *work)
+{
+	struct mc13783_ts_priv *priv =
+		container_of(work, struct mc13783_ts_priv, work.work);
+	unsigned int mode = MC13783_ADC_MODE_TS;
+	unsigned int channel = 12;
+	int ret;
+
+	ret = mc13783_adc_do_conversion
+		(priv->mc13783, mode, channel, priv->sample);
+
+	if (!ret)
+		mc13783_ts_report_sample(priv);
+}
+
+static int mc13783_ts_open(struct input_dev *dev)
+{
+	struct mc13783_ts_priv *priv = input_get_drvdata(dev);
+	int ret;
+
+	ret = mc13783_register_irq(priv->mc13783, MC13783_IRQ_TS,
+		mc13783_ts_handler, priv);
+	if (ret)
+		return ret;
+
+	queue_delayed_work(priv->workq, &priv->work, HZ / 20);
+
+	return 0;
+}
+
+static void mc13783_ts_close(struct input_dev *dev)
+{
+	struct mc13783_ts_priv *priv = input_get_drvdata(dev);
+
+	mc13783_free_irq(priv->mc13783, MC13783_IRQ_TS);
+}
+
+static int __devinit mc13783_ts_probe(struct platform_device *pdev)
+{
+	struct mc13783_ts_priv *priv;
+	struct input_dev *idev;
+	int ret;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->mc13783 = dev_get_drvdata(pdev->dev.parent);
+
+	idev = input_allocate_device();
+	if (!idev) {
+		ret = -ENOMEM;
+		goto err_input_alloc;
+	}
+
+	priv->idev = idev;
+	idev->name = MC13783_TS_NAME;
+	idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+	idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+	idev->absbit[0] = BIT_MASK(ABS_X) | BIT_MASK(ABS_Y);
+	idev->open = mc13783_ts_open;
+	idev->close = mc13783_ts_close;
+	input_set_abs_params(idev, ABS_X, TS_MIN, TS_MAX, 0, 0);
+	input_set_abs_params(idev, ABS_Y, TS_MIN, TS_MAX, 0, 0);
+
+	platform_set_drvdata(pdev, priv);
+
+	INIT_DELAYED_WORK(&priv->work, mc13783_ts_work);
+
+	priv->workq = create_singlethread_workqueue("mc13783_ts");
+	if (!priv->workq) {
+		ret = -ENOMEM;
+		goto err_input_alloc;
+	}
+
+	input_set_drvdata(idev, priv);
+
+	ret = input_register_device(priv->idev);
+	if (ret) {
+		dev_err(&pdev->dev,
+				"register input device failed with %d\n", ret);
+		goto err_failed_register;
+	}
+
+	/* unmask the ts wakeup interrupt */
+	mc13783_set_bits(priv->mc13783, MC13783_REG_INTERRUPT_MASK_0,
+			MC13783_INT_MASK_TSM, 0);
+
+	mc13783_adc_set_ts_status(priv->mc13783, 1);
+
+	return 0;
+
+err_failed_register:
+	input_free_device(priv->idev);
+err_input_alloc:
+	kfree(priv);
+
+	return ret;
+}
+
+static int __devexit mc13783_ts_remove(struct platform_device *pdev)
+{
+	struct mc13783_ts_priv *priv = platform_get_drvdata(pdev);
+
+	mc13783_adc_set_ts_status(priv->mc13783, 0);
+
+	cancel_delayed_work(&priv->work);
+	destroy_workqueue(priv->workq);
+
+	input_unregister_device(priv->idev);
+
+	kfree(priv);
+
+	return 0;
+}
+
+static struct platform_driver mc13783_ts_driver = {
+	.remove		= __devexit_p(mc13783_ts_remove),
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= MC13783_TS_NAME,
+	},
+};
+
+static int __init mc13783_ts_init(void)
+{
+	return platform_driver_probe(&mc13783_ts_driver, &mc13783_ts_probe);
+}
+
+static void __exit mc13783_ts_exit(void)
+{
+	platform_driver_unregister(&mc13783_ts_driver);
+}
+
+module_init(mc13783_ts_init);
+module_exit(mc13783_ts_exit);
+
+MODULE_DESCRIPTION("MC13783 input touchscreen driver");
+MODULE_AUTHOR("Sascha Hauer, <s.hauer@pengutronix.de>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mc13783-touch");