Hi,
I was wondering if you could provide a bit more detail on what this
driver is actually doing? My appologies if I have missed a
previous explanation. If so, please add a Documentation file
to explain what is going on.
The driver you have here does virtually nothing itself. It takes
both its source of interrupt and read function from platform
data. Given the value is always 0 or 1, I'm guessing you are
simply reading a gpio pin. That makes this effectively a button
and doesn't require any specific code. The fact it is a
proximity sensor isn't relevant to anything other than perhaps
the name.
One or two other points inline below.
Jonathan
On 05/12/10 16:26, Datta, Shubhrajyoti wrote:
>
> Driver support for the proximity sensor SFH7741.
>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@xxxxxx>
> ---
> drivers/input/misc/Kconfig | 9 ++
> drivers/input/misc/Makefile | 1 +
> drivers/input/misc/sfh7741.c | 256 +++++++++++++++++++++++++++++++++++++++++
> include/linux/input/sfh7741.h | 39 ++++++
> 4 files changed, 305 insertions(+), 0 deletions(-)
> create mode 100644 drivers/input/misc/sfh7741.c
> create mode 100644 include/linux/input/sfh7741.h
>
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 23140a3..ff30196 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -340,4 +340,13 @@ config INPUT_PCAP
> To compile this driver as a module, choose M here: the
> module will be called pcap_keys.
>
Why call the symbol SENSORS? Guessing this is a left over from
this being in hwmon at some point?
> +config SENSORS_SFH7741
> + tristate "Proximity sensor"
> + default n
> + help
> + Say Y here if you want to use proximity sensor sfh7741.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called sfh7741.
> +
> endif
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index 7e95a5d..5fea200 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -32,4 +32,5 @@ obj-$(CONFIG_INPUT_WINBOND_CIR) += winbond-cir.o
> obj-$(CONFIG_INPUT_WISTRON_BTNS) += wistron_btns.o
> obj-$(CONFIG_INPUT_WM831X_ON) += wm831x-on.o
> obj-$(CONFIG_INPUT_YEALINK) += yealink.o
> +obj-$(CONFIG_SENSORS_SFH7741) += sfh7741.o
>
> diff --git a/drivers/input/misc/sfh7741.c b/drivers/input/misc/sfh7741.c
> new file mode 100644
> index 0000000..3f54e98
> --- /dev/null
> +++ b/drivers/input/misc/sfh7741.c
> @@ -0,0 +1,256 @@
> +/*
> + * sfh7741.c
> + *
> + * SFH7741 Proximity Driver
> + *
> + * Copyright (C) 2010 Texas Instruments
> + *
> + * Author: Shubhrajyoti Datta <shubhrajyoti@xxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2 as published by
> + * the Free Software Foundation.
> + *
> + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/pm.h>
> +#include <linux/platform_device.h>
> +#include <linux/input.h>
> +#include <linux/input/sfh7741.h>
> +#include <linux/slab.h>
> +
> +struct sfh7741_drvdata {
> + struct input_dev *input;
> + int irq;
> + int prox_enable;
> + /* mutex for sysfs operations */
> + struct mutex lock;
> + void (*activate_func)(int state);
> + int (*read_prox)(void);
> +};
> +
> +static irqreturn_t sfh7741_isr(int irq, void *dev_id)
> +{
> + struct sfh7741_drvdata *ddata = dev_id;
> + int proximity;
> +
> + proximity = ddata->read_prox();
> + input_report_abs(ddata->input, ABS_DISTANCE, proximity);
> + input_sync(ddata->input);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static ssize_t set_prox_state(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + int state;
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> +
> + if (sscanf(buf, "%u", &state) != 1)
> + return -EINVAL;
> +
> + if ((state != 1) && (state != 0))
> + return -EINVAL;
> +
> + ddata->activate_func(state);
> +
> + mutex_lock(&ddata->lock);
> + if (state != ddata->prox_enable) {
> + if (state)
> + enable_irq(ddata->irq);
> + else
> + disable_irq(ddata->irq);
> + ddata->prox_enable = state;
> + }
> + mutex_unlock(&ddata->lock);
> + return strnlen(buf, count);
> +}
> +
> +static ssize_t show_prox_state(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> + return sprintf(buf, "%u\n", ddata->prox_enable);
> +}
> +static DEVICE_ATTR(state, S_IWUSR | S_IRUGO, show_prox_state, set_prox_state);
> +
> +static ssize_t show_proximity(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + int proximity;
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> + proximity = ddata->read_prox();
> + return sprintf(buf, "%u\n", proximity);
> +}
> +static DEVICE_ATTR(proximity, S_IRUGO, show_proximity, NULL);
> +
> +static struct attribute *sfh7741_attributes[] = {
> + &dev_attr_state.attr,
> + &dev_attr_proximity.attr,
> + NULL
> +};
> +
> +static const struct attribute_group sfh7741_attr_group = {
> + .attrs = sfh7741_attributes,
> +};
> +
> +static int __devinit sfh7741_probe(struct platform_device *pdev)
> +{
> + struct sfh7741_platform_data *pdata = pdev->dev.platform_data;
> + struct sfh7741_drvdata *ddata;
> + struct device *dev = &pdev->dev;
> + struct input_dev *input;
> + int error;
> + char *desc = "sfh7741";
> +
> + pr_info("SFH7741: Proximity sensor\n");
> +
> + ddata = kzalloc(sizeof(struct sfh7741_drvdata),
> + GFP_KERNEL);
> + input = input_allocate_device();
> + if (!ddata || !input) {
> + dev_err(dev, "failed to allocate input device\n");
> + return -ENOMEM;
> + }
> +
> + input->name = pdev->name;
> + input->phys = "sfh7741/input0";
> + input->dev.parent = &pdev->dev;
> +
> + input->id.bustype = BUS_HOST;
> + ddata->irq = pdata->irq;
> + ddata->prox_enable = pdata->prox_enable;
> + if (!pdata->activate_func || !pdata->read_prox) {
> + dev_err(dev, "The activate and read func not allocated\n");
> + kfree(ddata);
> + return -EINVAL;
> + }
> +
> + ddata->activate_func = pdata->activate_func;
> + ddata->read_prox = pdata->read_prox;
> +
> + ddata->input = input;
> + __set_bit(EV_ABS, input->evbit);
> +
> + input_set_abs_params(input, ABS_DISTANCE, 0, 1, 0, 0);
If this is an absolute signal, why is it between 0 and 1, that looks
rather binary to me.
> +
> + error = input_register_device(input);
> + if (error) {
> + dev_err(dev, "Unable to register input device,error: %d\n"
> + , error);
> + goto fail1;
> + }
> +
> + platform_set_drvdata(pdev, ddata);
> +
> + error = request_threaded_irq(pdata->irq , NULL ,
> + sfh7741_isr,
> + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING
> + | IRQF_ONESHOT,
> + desc, ddata);
> + if (error) {
> + dev_err(dev, "Unable to claim irq %d; error %d\n",
> + pdata->irq, error);
> + goto fail2;
> + }
> +
> + mutex_init(&ddata->lock);
> + error = sysfs_create_group(&dev->kobj, &sfh7741_attr_group);
> + if (error) {
> + dev_err(dev, "failed to create sysfs entries\n");
> + mutex_destroy(&ddata->lock);
> + }
> +
> + return 0;
> +
> +fail2:
> + input_unregister_device(input);
> + platform_set_drvdata(pdev, NULL);
> +fail1:
> + input_free_device(input);
> + kfree(ddata);
> + return error;
> +
> +}
> +
> +static int __devexit sfh7741_remove(struct platform_device *pdev)
> +{
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> + struct device *dev = &pdev->dev;
> + mutex_destroy(&ddata->lock);
> + sysfs_remove_group(&dev->kobj, &sfh7741_attr_group);
> + free_irq(ddata->irq, (void *)ddata);
> + input_unregister_device(ddata->input);
> + kfree(ddata);
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int sfh7741_suspend(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> + ddata->activate_func(0);
> + return 0;
> +}
> +
> +static int sfh7741_resume(struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct sfh7741_drvdata *ddata = platform_get_drvdata(pdev);
> + ddata->activate_func(1);
> + return 0;
> +}
> +
> +static const struct dev_pm_ops sfh7741_pm_ops = {
> + .suspend = sfh7741_suspend,
> + .resume = sfh7741_resume,
> +};
> +#endif
> +
> +static struct platform_driver sfh7741_device_driver = {
> + .probe = sfh7741_probe,
> + .remove = __devexit_p(sfh7741_remove),
> + .driver = {
> + .name = "sfh7741",
> + .owner = THIS_MODULE,
> +#ifdef CONFIG_PM
> + .pm = &sfh7741_pm_ops,
> +#endif
> + }
> +};
> +
> +static int __init sfh7741_init(void)
> +{
> + return platform_driver_register(&sfh7741_device_driver);
> +}
> +
> +static void __exit sfh7741_exit(void)
> +{
> + platform_driver_unregister(&sfh7741_device_driver);
> +}
> +
> +module_init(sfh7741_init);
> +module_exit(sfh7741_exit);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Texas Instruments");
> +MODULE_DESCRIPTION("Proximity sensor SFH7741 driver");
> +MODULE_ALIAS("platform:sfh7741");
> +
> diff --git a/include/linux/input/sfh7741.h b/include/linux/input/sfh7741.h
> new file mode 100644
> index 0000000..18868e0
> --- /dev/null
> +++ b/include/linux/input/sfh7741.h
> @@ -0,0 +1,39 @@
> +/*
> + * sfh7741.h
> + * SFH7741 Proximity sensor driver
> + *
> + * Copyright (C) 2010 Texas Instruments
> + * Author: Shubhrajyoti D <shubhrajyoti@xxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2 as published by
> + * the Free Software Foundation.
> + *
> + * 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 <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef __SFH7741_H
> +#define __SFH7741_H
> +
> +/*
> + * struct sfh7741_platform_data - SFH7741 Platform data
> + * @irq: IRQ assigned
> + * @prox_enable: State of the sensor
> + * @activate_func: function called to activate/deactivate the sensor
> + * @read_prox: function to read the sensor output
> + */
> +struct sfh7741_platform_data {
> + int irq;
> + int prox_enable;
> + void (*activate_func)(int state);
> + int (*read_prox)(void);
> +};
> +
> +#endif
> +
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