[PATCH] input: add driver for pixcir i2c touchscreens

This patch adds a driver for PIXCIR's I2C connected touchscreens.

Signed-off-by: Bee <redacted>
---
drivers/input/touchscreen/Kconfig | 9 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/pixcir_i2c_ts.c | 293
+++++++++++++++++++++++++++++
3 files changed, 303 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/pixcir_i2c_ts.c

diff --git a/drivers/input/touchscreen/Kconfig

b/drivers/input/touchscreen/Kconfig
index 61834ae..f11c1ab 100644

--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig

@@ -693,4 +693,13 @@ config TOUCHSCREEN_TPS6507X

To compile this driver as a module, choose M here: the
module will be called tps6507x_ts.

+config TOUCHSCREEN_PIXCIR
+ tristate "PIXCIR touchscreen panel support"
+ depends on I2C
+ help
+ Say Y here if you have a PIXCIR based touchscreen.
+
+ To compile this driver as a module, choose M here: the
+ module will be called pixcir_i2c_ts.
+
endif

diff --git a/drivers/input/touchscreen/Makefile

b/drivers/input/touchscreen/Makefile
index 718bcc8..4513668 100644

--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile

@@ -57,3 +57,4 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) +=

mainstone-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE) += zylonite-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_W90X900) += w90p910_ts.o
obj-$(CONFIG_TOUCHSCREEN_TPS6507X) += tps6507x-ts.o
+obj-$(CONFIG_TOUCHSCREEN_PIXCIR) += pixcir_i2c_ts.o

diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c

b/drivers/input/touchscreen/pixcir_i2c_ts.c
new file mode 100644
index 0000000..e3fbeb0

--- /dev/null
+++ b/drivers/input/touchscreen/pixcir_i2c_ts.c

@@ -0,0 +1,293 @@
+/* drivers/input/touchscreen/pixcir_i2c_ts.c
+ *
+ * Copyright (C) 2010-2011 Pixcir, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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 library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+
+#define DRIVER_VERSION "v1.0"
+#define DRIVER_AUTHOR

"Bee[off-list ref],Reed[off-list ref]"
+#define DRIVER_DESC "Pixcir I2C Touchscreen Driver"
+#define DRIVER_LICENSE "GPL"
+
+/* todo:check specs for resolution of touch screen */
+#define TOUCHSCREEN_MINX 0
+#define TOUCHSCREEN_MAXX 400
+#define TOUCHSCREEN_MINY 0
+#define TOUCHSCREEN_MAXY 600
+
+#define DEBUG 0
+
+static struct workqueue_struct *pixcir_wq;
+
+struct pixcir_i2c_ts_data {
+ struct i2c_client *client;
+ struct input_dev *input;
+ struct delayed_work work;
+ int irq;
+};
+
+static void pixcir_ts_poscheck(struct work_struct *work)
+{
+ struct pixcir_i2c_ts_data *tsdata = container_of(work,
+ struct pixcir_i2c_ts_data,
+ work.work);
+
+ unsigned char touching, oldtouching;
+ int posx1, posy1, posx2, posy2;
+ u_int8_t Rdbuf[10], Wrbuf[1];
+ int ret;
+ int z = 50;
+ int w = 15;
+
+ memset(Wrbuf, 0, sizeof(Wrbuf));
+ memset(Rdbuf, 0, sizeof(Rdbuf));
+
+ Wrbuf[0] = 0;
+ ret = i2c_master_send(tsdata->client, Wrbuf, 1);
+ if (ret != 1) {
+ dev_err(&tsdata->client->dev, "Unable to write to i2c touchscreen!\n");
+ goto out;
+ }
+
+ ret = i2c_master_recv(tsdata->client, Rdbuf, sizeof(Rdbuf));
+ if (ret != sizeof(Rdbuf)) {
+ dev_err(&tsdata->client->dev, "Unable to read i2c page!\n");
+ goto out;
+ }
+
+ touching = Rdbuf[0];
+ oldtouching = Rdbuf[1];
+ posx1 = ((Rdbuf[3] << 8) | Rdbuf[2]);
+ posy1 = ((Rdbuf[5] << 8) | Rdbuf[4]);
+ posx2 = ((Rdbuf[7] << 8) | Rdbuf[6]);
+ posy2 = ((Rdbuf[9] << 8) | Rdbuf[8]);
+
+ input_report_key(tsdata->input, BTN_TOUCH, (touching != 0 ? 1 : 0));
+
+ if (touching == 1) {
+ input_report_abs(tsdata->input, ABS_X, posx1);
+ input_report_abs(tsdata->input, ABS_Y, posy1);
+ }
+
+ if (!(touching)) {
+ z = 0;
+ w = 0;
+ }
+ if (touching == 2) {
+ input_report_abs(tsdata->input, ABS_MT_TOUCH_MAJOR, z);
+ input_report_abs(tsdata->input, ABS_MT_WIDTH_MAJOR, w);
+ input_report_abs(tsdata->input, ABS_MT_POSITION_X, posx1);
+ input_report_abs(tsdata->input, ABS_MT_POSITION_Y, posy1);
+ input_mt_sync(tsdata->input);
+
+ input_report_abs(tsdata->input, ABS_MT_TOUCH_MAJOR, z);
+ input_report_abs(tsdata->input, ABS_MT_WIDTH_MAJOR, w);
+ input_report_abs(tsdata->input, ABS_MT_POSITION_X, posx2);
+ input_report_abs(tsdata->input, ABS_MT_POSITION_Y, posy2);
+ input_mt_sync(tsdata->input);
+ }
+ input_sync(tsdata->input);
+
+out:
+ enable_irq(tsdata->irq);
+}
+
+static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_id;
+ disable_irq_nosync(irq);
+
+ queue_work(pixcir_wq, &tsdata->work.work);
+
+ return IRQ_HANDLED;
+}
+
+static int pixcir_ts_open(struct input_dev *dev)
+{
+ return 0;
+}
+
+static void pixcir_ts_close(struct input_dev *dev)
+{
+
+}
+
+static int pixcir_i2c_ts_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct pixcir_i2c_ts_data *tsdata;
+ struct input_dev *input;
+ int error;
+
+ #ifdef DEBUG
+ printk(KERN_EMERG "pixcir_i2c_ts probe!\n");
+ #endif
+
+ tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
+ if (!tsdata) {
+ dev_err(&client->dev, "Failed to allocate driver data!\n");
+ error = -ENOMEM;
+ dev_set_drvdata(&client->dev, NULL);
+ return error;
+ }
+
+ dev_set_drvdata(&client->dev, tsdata);
+
+ input = input_allocate_device();
+ if (!input) {
+ dev_err(&client->dev, "Failed to allocate input device!\n");
+ error = -ENOMEM;
+ input_free_device(input);
+ kfree(tsdata);
+ }
+
+ set_bit(EV_SYN, input->evbit);
+ set_bit(EV_KEY, input->evbit);
+ set_bit(EV_ABS, input->evbit);
+ set_bit(BTN_TOUCH, input->keybit);
+ input_set_abs_params(input, ABS_X,
+ TOUCHSCREEN_MINX, TOUCHSCREEN_MAXX, 0, 0);
+ input_set_abs_params(input, ABS_Y,
+ TOUCHSCREEN_MINY, TOUCHSCREEN_MAXY, 0, 0);
+ input_set_abs_params(input, ABS_MT_POSITION_X,
+ TOUCHSCREEN_MINX, TOUCHSCREEN_MAXX, 0, 0);
+ input_set_abs_params(input, ABS_MT_POSITION_Y,
+ TOUCHSCREEN_MINY, TOUCHSCREEN_MAXY, 0, 0);
+ input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
+ input_set_abs_params(input, ABS_MT_WIDTH_MAJOR, 0, 25, 0, 0);
+
+ input->name = client->name;
+ input->id.bustype = BUS_I2C;
+ input->dev.parent = &client->dev;
+
+ input->open = pixcir_ts_open;
+ input->close = pixcir_ts_close;
+
+ input_set_drvdata(input, tsdata);
+
+ tsdata->client = client;
+ tsdata->input = input;
+
+ INIT_WORK(&tsdata->work.work, pixcir_ts_poscheck);
+
+ tsdata->irq = client->irq;
+
+ if (input_register_device(input)) {
+ input_free_device(input);
+ kfree(tsdata);
+ }
+
+ if (request_irq(tsdata->irq, pixcir_ts_isr,
+ IRQF_TRIGGER_LOW, client->name, tsdata)) {
+ dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+ input_unregister_device(input);
+ input = NULL;
+ }
+
+ device_init_wakeup(&client->dev, 1);
+
+ dev_err(&tsdata->client->dev, "insmod successfully!\n");
+
+ return 0;
+}
+
+static int pixcir_i2c_ts_remove(struct i2c_client *client)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_get_drvdata(&client->dev);
+ free_irq(tsdata->irq, tsdata);
+ input_unregister_device(tsdata->input);
+ kfree(tsdata);
+ dev_set_drvdata(&client->dev, NULL);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int pixcir_i2c_ts_suspend(struct i2c_client *client,
pm_message_t mesg)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(tsdata->irq);
+
+ return 0;
+}
+
+static int pixcir_i2c_ts_resume(struct i2c_client *client)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(tsdata->irq);
+
+ return 0;
+}
+#else
+#define pixcir_i2c_ts_suspend NULL
+#define pixcir_i2c_ts_resume NULL
+#endif
+
+static const struct i2c_device_id pixcir_i2c_ts_id[] = {
+ { "pixcir_ts", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);
+
+static struct i2c_driver pixcir_i2c_ts_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "pixcir_ts",
+ },
+ .probe = pixcir_i2c_ts_probe,
+ .remove = pixcir_i2c_ts_remove,
+ .suspend = pixcir_i2c_ts_suspend,
+ .resume = pixcir_i2c_ts_resume,
+ .id_table = pixcir_i2c_ts_id,
+};
+
+static int __init pixcir_i2c_ts_init(void)
+{
+ #ifdef DEBUG
+ printk(KERN_EMERG "pixcir_i2c_init\n");
+ #endif
+
+ pixcir_wq = create_singlethread_workqueue("pixcir_wq");
+ if (!pixcir_wq)
+ return -ENOMEM;
+ return i2c_add_driver(&pixcir_i2c_ts_driver);
+}
+
+static void __exit pixcir_i2c_ts_exit(void)
+{
+ #ifdef DEBUG
+ printk(KERN_EMERG "pixcir_i2c_exit\n");
+ #endif
+
+ i2c_del_driver(&pixcir_i2c_ts_driver);
+ if (pixcir_wq)
+ destroy_workqueue(pixcir_wq);
+}
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE(DRIVER_LICENSE);
+
+module_init(pixcir_i2c_ts_init);
+module_exit(pixcir_i2c_ts_exit);
-- 
1.7.0.4

On Tue, Feb 22, 2011 at 11:17:01AM +0800, jcbian wrote:

+config TOUCHSCREEN_PIXCIR
+ tristate "PIXCIR touchscreen panel support"
+ depends on I2C
+ help
+ Say Y here if you have a PIXCIR based touchscreen.
+
+ To compile this driver as a module, choose M here: the
+ module will be called pixcir_i2c_ts.

It looks like your mail client messes with the indentation of your
files, it looks like it turned all the tabs into spaces.

+#define DEBUG 0

Best just to remove this.

+static struct workqueue_struct *pixcir_wq;

If you can have a single global workqueue could you use the system one
and avoid having to create one at all?

+ int posx1, posy1, posx2, posy2;
+ u_int8_t Rdbuf[10], Wrbuf[1];

Use u8.  The upper case at the start of teh bariable names is also a bit
odd for Linux.

+ Wrbuf[0] = 0;
+ ret = i2c_master_send(tsdata->client, Wrbuf, 1);
+ if (ret != 1) {
+ dev_err(&tsdata->client->dev, "Unable to write to i2c touchscreen!\n");
+ goto out;

It'd be good to print the error code.

+static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_id;
+ disable_irq_nosync(irq);
+
+ queue_work(pixcir_wq, &tsdata->work.work);
+
+ return IRQ_HANDLED;
+}

Use a threaded IRQ handler - genirq can now implement this pattern for
you.

+static int pixcir_ts_open(struct input_dev *dev)
+{
+ return 0;
+}

You should have code to start the controller here, and matching shutdown
code in close().

+ #ifdef DEBUG
+ printk(KERN_EMERG "pixcir_i2c_ts probe!\n");
+ #endif

dev_dbg() or just remove this.

+ tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
+ if (!tsdata) {
+ dev_err(&client->dev, "Failed to allocate driver data!\n");
+ error = -ENOMEM;
+ dev_set_drvdata(&client->dev, NULL);

Don't need to clear the driver data if you're exiting.

+ if (request_irq(tsdata->irq, pixcir_ts_isr,
+ IRQF_TRIGGER_LOW, client->name, tsdata)) {
+ dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+ input_unregister_device(input);
+ input = NULL;
+ }

Your error handling doesn't aways clean everything up - it's often best
to use gotos to jump to cleanup code that unwinds everything to make
sure you don't miss some things.

+
+ dev_err(&tsdata->client->dev, "insmod successfully!\n");

No need for logs like this in production code, and the priority is all
wrong.

+#ifdef CONFIG_PM
+static int pixcir_i2c_ts_suspend(struct i2c_client *client,
pm_message_t mesg)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(tsdata->irq);
+
+ return 0;
+}

Please use dev_pm_ops instead of bus-specific suspend/resume callbacks -
there is a general move to remove the bus specific ones to allow better
development of the PM core.

+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE(DRIVER_LICENSE);

Just put the definitions of these in directly, they're only used in one
place.

Dear Mark
  Thanks for your feedbaxk!

On Tue, Feb 22, 2011 at 11:17:01AM +0800, jcbian wrote:

quoted

+config TOUCHSCREEN_PIXCIR
+ tristate "PIXCIR touchscreen panel support"
+ depends on I2C
+ help
+ Say Y here if you have a PIXCIR based touchscreen.
+
+ To compile this driver as a module, choose M here: the
+ module will be called pixcir_i2c_ts.

It looks like your mail client messes with the indentation of your
files, it looks like it turned all the tabs into spaces.

Yes,so I resend the patch v2 which send from web.

quoted

+#define DEBUG 0

Best just to remove this.

Nice.

quoted

+static struct workqueue_struct *pixcir_wq;

If you can have a single global workqueue could you use the system one
and avoid having to create one at all?

The system one is less efficient then the the creating one in my opioion,is it right?

quoted

+ int posx1, posy1, posx2, posy2;
+ u_int8_t Rdbuf[10], Wrbuf[1];

Use u8.  The upper case at the start of teh bariable names is also a bit
odd for Linux.

Nice.

quoted

+ Wrbuf[0] = 0;
+ ret = i2c_master_send(tsdata->client, Wrbuf, 1);
+ if (ret != 1) {
+ dev_err(&tsdata->client->dev, "Unable to write to i2c touchscreen!\n");
+ goto out;

It'd be good to print the error code.

Great.

quoted

+static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_id;
+ disable_irq_nosync(irq);
+
+ queue_work(pixcir_wq, &tsdata->work.work);
+
+ return IRQ_HANDLED;
+}

Use a threaded IRQ handler - genirq can now implement this pattern for
you.

I do not use genirq before, what the diffetence? Thanks!

quoted

+static int pixcir_ts_open(struct input_dev *dev)
+{
+ return 0;
+}

You should have code to start the controller here, and matching shutdown
code in close().

Yes normally should do like this,but this controller need any command to open,may be take come code
to test the device working? 

quoted

+ #ifdef DEBUG
+ printk(KERN_EMERG "pixcir_i2c_ts probe!\n");
+ #endif

dev_dbg() or just remove this.

Nice.

quoted

+ tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
+ if (!tsdata) {
+ dev_err(&client->dev, "Failed to allocate driver data!\n");
+ error = -ENOMEM;
+ dev_set_drvdata(&client->dev, NULL);

Don't need to clear the driver data if you're exiting.

Well,

quoted

+ if (request_irq(tsdata->irq, pixcir_ts_isr,
+ IRQF_TRIGGER_LOW, client->name, tsdata)) {
+ dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+ input_unregister_device(input);
+ input = NULL;
+ }

Your error handling doesn't aways clean everything up - it's often best
to use gotos to jump to cleanup code that unwinds everything to make
sure you don't miss some things.

Nice advice.

quoted

+
+ dev_err(&tsdata->client->dev, "insmod successfully!\n");

No need for logs like this in production code, and the priority is all
wrong.

I just want to show the correctly insmod.

quoted

+#ifdef CONFIG_PM
+static int pixcir_i2c_ts_suspend(struct i2c_client *client,
pm_message_t mesg)
+{
+ struct pixcir_i2c_ts_data *tsdata = dev_get_drvdata(&client->dev);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(tsdata->irq);
+
+ return 0;
+}

Please use dev_pm_ops instead of bus-specific suspend/resume callbacks -
there is a general move to remove the bus specific ones to allow better
development of the PM core.

Great idea, I never notice the dev_pm_ops before,thanks!

quoted

+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE(DRIVER_LICENSE);

Just put the definitions of these in directly, they're only used in one
place.

Nice.

On Wed, Feb 23, 2011 at 09:04:28AM +0800, jcbian wrote:

quoted

On Tue, Feb 22, 2011 at 11:17:01AM +0800, jcbian wrote:

quoted

If you can have a single global workqueue could you use the system one
and avoid having to create one at all?

The system one is less efficient then the the creating one in my opioion,is it right?

Actually this is obsoleted by the comment below since you're using the
workqueue for interrupt handling only.

quoted

quoted

+ queue_work(pixcir_wq, &tsdata->work.work);

quoted

quoted

+ return IRQ_HANDLED;
+}

quoted

Use a threaded IRQ handler - genirq can now implement this pattern for
you.

I do not use genirq before, what the diffetence? Thanks!

genirq is the name of the standard kernel interrupt implementation.  If
you use a threaded IRQ handler using request_threaded_irq() then all the
workqueue stuff goes away.

quoted

quoted

+static int pixcir_ts_open(struct input_dev *dev)
+{
+ return 0;
+}

quoted

You should have code to start the controller here, and matching shutdown
code in close().

Yes normally should do like this,but this controller need any command to open,may be take come code
to test the device working? 

If there's nothing at all to do I guess you can remove the code, though
at least disabling the IRQ while the device is closed would be nice.

quoted

quoted

+ dev_err(&tsdata->client->dev, "insmod successfully!\n");

quoted

No need for logs like this in production code, and the priority is all
wrong.

I just want to show the correctly insmod.

It's not something that should be shown in production code.

quoted

quoted

quoted

+ queue_work(pixcir_wq, &tsdata->work.work);

quoted

quoted

quoted

+ return IRQ_HANDLED;
+}

quoted

quoted

Use a threaded IRQ handler - genirq can now implement this pattern for
you.

quoted

I do not use genirq before, what the diffetence? Thanks!

genirq is the name of the standard kernel interrupt implementation.  If
you use a threaded IRQ handler using request_threaded_irq() then all the
workqueue stuff goes away.

Oh,understand,thanks!It seems that request_threaded_irq() is more intelligent :)

Thanks

---
Jcbian