[PATCH 0/3] NI Ettus Research USRP E3x0 Button driver

[PATCH 0/3] NI Ettus Research USRP E3x0 Button driver

[Moritz Fischer]

This patchset adds NI Ettus Research USRP E3x0 power button support and
corresponding devicetree bindings and MAINTAINER entries.

It was developed and tested on our NI Ettus Research USRP E310 embedded
SDR on top of 3.19-rc3.

Moritz Fischer (3):
  input: misc: Support NI Ettus Research USRP E3x0 Button
  doc: dt: Add documentation for e3x0-button bindings.
  Update MAINTAINERS file with e3x0-button info.

 .../devicetree/bindings/input/e3x0-button.txt      |  25 ++++
 MAINTAINERS                                        |   8 ++
 drivers/input/misc/Kconfig                         |  10 ++
 drivers/input/misc/Makefile                        |   1 +
 drivers/input/misc/e3x0-button.c                   | 153 +++++++++++++++++++++
 5 files changed, 197 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/e3x0-button.txt
 create mode 100644 drivers/input/misc/e3x0-button.c

-- 
1.9.3

[PATCH 1/3] input: misc: Support NI Ettus Research USRP E3x0 Button

[Moritz Fischer]

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
---
 drivers/input/misc/Kconfig       |  10 +++
 drivers/input/misc/Makefile      |   1 +
 drivers/input/misc/e3x0-button.c | 153 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 164 insertions(+)

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 23297ab..84a56b4 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -93,6 +93,16 @@ config INPUT_BMA150
 	  To compile this driver as a module, choose M here: the
 	  module will be called bma150.
 
+config INPUT_E3X0_BUTTON
+	tristate "NI Ettus Research USRP E3x0 Button support."
+	default n
+	help
+	  Say Y here to enable support for the NI Ettus Research
+	  USRP E3x0 Button.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called e3x0_button.
+
 config INPUT_PCSPKR
 	tristate "PC Speaker support"
 	depends on PCSPKR_PLATFORM
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 19c7603..b1775a5 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_INPUT_COBALT_BTNS)		+= cobalt_btns.o
 obj-$(CONFIG_INPUT_DA9052_ONKEY)	+= da9052_onkey.o
 obj-$(CONFIG_INPUT_DA9055_ONKEY)	+= da9055_onkey.o
 obj-$(CONFIG_INPUT_DM355EVM)		+= dm355evm_keys.o
+obj-$(CONFIG_INPUT_E3X0_BUTTON)		+= e3x0-button.o
 obj-$(CONFIG_INPUT_DRV260X_HAPTICS)	+= drv260x.o
 obj-$(CONFIG_INPUT_DRV2667_HAPTICS)	+= drv2667.o
 obj-$(CONFIG_INPUT_GP2A)		+= gp2ap002a00f.o
diff --git a/drivers/input/misc/e3x0-button.c b/drivers/input/misc/e3x0-button.c
new file mode 100644
index 0000000..0022f6a
--- /dev/null
+++ b/drivers/input/misc/e3x0-button.c
@@ -0,0 +1,153 @@
+/*
+ * Copyright (c) 2014, National Instruments Corp. All rights reserved.
+ *
+ * Driver for NI Ettus Research USRP E3x0 Button Driver
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+/**
+ * struct e3x0_button - e3x0 button information
+ * @input_dev: pointer to input device
+ * @irq_press: irq number for press event
+ * @irq_release: irq number for release event
+ */
+struct e3x0_button {
+	struct input_dev	*idev;
+	int			irq_press;
+	int			irq_release;
+};
+
+static irqreturn_t e3x0_button_handler(int irq, void *data)
+{
+	struct e3x0_button *button = data;
+
+	if (irq == button->irq_press)
+		input_report_key(button->idev, KEY_POWER, 1);
+	else if (irq == button->irq_release)
+		input_report_key(button->idev, KEY_POWER, 0);
+
+	input_sync(button->idev);
+
+	return IRQ_HANDLED;
+}
+
+static int e3x0_button_probe(struct platform_device *pdev)
+{
+	struct e3x0_button *button;
+	struct input_dev *input;
+	int irq_press, irq_release;
+	int error;
+
+	irq_press = platform_get_irq_byname(pdev, "press");
+	if (irq_press < 0) {
+		dev_err(&pdev->dev, "No IRQ for 'press', error=%d\n",
+			irq_press);
+		return irq_press;
+	}
+
+	irq_release = platform_get_irq_byname(pdev, "release");
+	if (irq_release < 0) {
+		dev_err(&pdev->dev, "No IRQ for 'release', error=%d\n",
+			irq_release);
+		return irq_release;
+	}
+
+	button = devm_kzalloc(&pdev->dev, sizeof(*button),
+			      GFP_KERNEL);
+	if (!button)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	button->idev = input;
+	button->irq_press = irq_press;
+	button->irq_release = irq_release;
+
+	input->name = "NI Ettus Research USRP E3x0 Button Driver";
+	input->phys = "e3x0_button/input0";
+	input->dev.parent = &pdev->dev;
+
+	input_set_capability(input, EV_KEY, KEY_POWER);
+
+	error = devm_request_irq(&pdev->dev, button->irq_press,
+					     e3x0_button_handler, 0,
+					     "e3x0-button", button);
+	if (error < 0) {
+		dev_err(&pdev->dev, "Failed to request 'press' IRQ#%d: %d\n",
+			button->irq_press, error);
+		return error;
+	}
+
+	error = devm_request_irq(&pdev->dev, button->irq_release,
+					     e3x0_button_handler, 0,
+					     "e3x0-button", button);
+	if (error < 0) {
+		dev_err(&pdev->dev, "Failed to request 'release' IRQ#%d: %d\n",
+			button->irq_release, error);
+		return error;
+	}
+
+	error = input_register_device(button->idev);
+	if (error) {
+		dev_err(&pdev->dev, "Can't register input device: %d\n", error);
+		return error;
+	}
+
+	platform_set_drvdata(pdev, button);
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id e3x0_button_match[] = {
+	{ .compatible = "ettus,e3x0-button", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, e3x0_button_match);
+#endif
+
+static struct platform_driver e3x0_button_driver = {
+	.driver		= {
+		.name	= "e3x0-button",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(e3x0_button_match),
+	},
+	.probe		= e3x0_button_probe,
+};
+
+static int __init e3x0_button_init(void)
+{
+	pr_info("e3x0-button: Copyright (c) 2014 National Instruments Corp");
+	return platform_driver_register(&e3x0_button_driver);
+}
+
+static void e3x0_button_exit(void)
+{
+	platform_driver_unregister(&e3x0_button_driver);
+}
+
+module_init(e3x0_button_init);
+module_exit(e3x0_button_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
+MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver");
+MODULE_ALIAS("platform:e3x0-button");
-- 
1.9.3

[PATCH 2/3] doc: dt: Add documentation for e3x0-button bindings.

[Moritz Fischer]

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
---
 .../devicetree/bindings/input/e3x0-button.txt      | 25 ++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/e3x0-button.txt b/Documentation/devicetree/bindings/input/e3x0-button.txt
new file mode 100644
index 0000000..751665e
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/e3x0-button.txt
@@ -0,0 +1,25 @@
+National Instruments Ettus Research USRP E3x0 button driver
+
+This module is part of the NI Ettus Research USRP E3x0 SDR.
+
+This module provides a simple power button event via two interrupts.
+
+Required properties:
+- compatible: should be one of the following
+  - "ettus,e3x0-button": For devices such as the NI Ettus Research USRP E3x0
+- interrupt-parent:
+  - a phandle to the interrupt controller that it is attached to.
+- interrupts: should be one of the following
+  - <0 30 1>, <0 31 1>: For devices such as the NI Ettus Research USRP E3x0
+- interrupt-names: should be one of the following
+  - "press", "release": For devices such as the NI Ettus Research USRP E3x0
+
+Note: Interrupt numbers might vary depending on the FPGA configuration.
+
+Example:
+	button {
+		compatible = "ettus,e3x0-button";
+		interrupt-parent = <&intc>;
+		interrupts = <0 30 1>, <0 31 1>;
+		interrupt-names = "press", "release";
+	}
-- 
1.9.3

[PATCH 3/3] Update MAINTAINERS file with e3x0-button info.

[Moritz Fischer]

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index ddb9ac8..65358d1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3466,6 +3466,14 @@ M:	"Maciej W. Rozycki" <macro@linux-mips.org>
 S:	Maintained
 F:	drivers/tty/serial/dz.*
 
+E3X0 POWER BUTTON DRIVER
+M:	Moritz Fischer <moritz.fischer@ettus.com>
+L:	usrp-users@lists.ettus.com
+W:	http://www.ettus.com
+S:	Supported
+F:	drivers/input/misc/e3x0-button.c
+F:	Documentation/devicetree/bindings/input/e3x0-button.txt
+
 E4000 MEDIA DRIVER
 M:	Antti Palosaari <crope@iki.fi>
 L:	linux-media@vger.kernel.org
-- 
1.9.3

Re: [PATCH 1/3] input: misc: Support NI Ettus Research USRP E3x0 Button

[Dmitry Torokhov]

On Thu, Jan 08, 2015 at 10:02:49PM +0100, Moritz Fischer wrote:
> Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
> ---
>  drivers/input/misc/Kconfig       |  10 +++
>  drivers/input/misc/Makefile      |   1 +
>  drivers/input/misc/e3x0-button.c | 153 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 164 insertions(+)
> 
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 23297ab..84a56b4 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -93,6 +93,16 @@ config INPUT_BMA150
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called bma150.
>  
> +config INPUT_E3X0_BUTTON
> +	tristate "NI Ettus Research USRP E3x0 Button support."
> +	default n
> +	help
> +	  Say Y here to enable support for the NI Ettus Research
> +	  USRP E3x0 Button.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called e3x0_button.
> +
>  config INPUT_PCSPKR
>  	tristate "PC Speaker support"
>  	depends on PCSPKR_PLATFORM
> diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
> index 19c7603..b1775a5 100644
> --- a/drivers/input/misc/Makefile
> +++ b/drivers/input/misc/Makefile
> @@ -26,6 +26,7 @@ obj-$(CONFIG_INPUT_COBALT_BTNS)		+= cobalt_btns.o
>  obj-$(CONFIG_INPUT_DA9052_ONKEY)	+= da9052_onkey.o
>  obj-$(CONFIG_INPUT_DA9055_ONKEY)	+= da9055_onkey.o
>  obj-$(CONFIG_INPUT_DM355EVM)		+= dm355evm_keys.o
> +obj-$(CONFIG_INPUT_E3X0_BUTTON)		+= e3x0-button.o
>  obj-$(CONFIG_INPUT_DRV260X_HAPTICS)	+= drv260x.o
>  obj-$(CONFIG_INPUT_DRV2667_HAPTICS)	+= drv2667.o
>  obj-$(CONFIG_INPUT_GP2A)		+= gp2ap002a00f.o
> diff --git a/drivers/input/misc/e3x0-button.c b/drivers/input/misc/e3x0-button.c
> new file mode 100644
> index 0000000..0022f6a
> --- /dev/null
> +++ b/drivers/input/misc/e3x0-button.c
> @@ -0,0 +1,153 @@
> +/*
> + * Copyright (c) 2014, National Instruments Corp. All rights reserved.
> + *
> + * Driver for NI Ettus Research USRP E3x0 Button Driver
> + *
> + * 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; version 2 of the License.
> + *
> + * 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.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/of.h>
> +#include <linux/slab.h>
> +
> +/**
> + * struct e3x0_button - e3x0 button information
> + * @input_dev: pointer to input device
> + * @irq_press: irq number for press event
> + * @irq_release: irq number for release event
> + */
> +struct e3x0_button {
> +	struct input_dev	*idev;
> +	int			irq_press;
> +	int			irq_release;
> +};
> +
> +static irqreturn_t e3x0_button_handler(int irq, void *data)
> +{
> +	struct e3x0_button *button = data;
> +
> +	if (irq == button->irq_press)
> +		input_report_key(button->idev, KEY_POWER, 1);
> +	else if (irq == button->irq_release)
> +		input_report_key(button->idev, KEY_POWER, 0);

Hmm, if you create a separate IRSs for press and release you would not
need to store irq_press and irq_release and consequently would not have
to use/allocate e3x0_button structure at all (unless you are planning to
expand the driver later).

> +
> +	input_sync(button->idev);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int e3x0_button_probe(struct platform_device *pdev)
> +{
> +	struct e3x0_button *button;
> +	struct input_dev *input;
> +	int irq_press, irq_release;
> +	int error;
> +
> +	irq_press = platform_get_irq_byname(pdev, "press");
> +	if (irq_press < 0) {
> +		dev_err(&pdev->dev, "No IRQ for 'press', error=%d\n",
> +			irq_press);
> +		return irq_press;
> +	}
> +
> +	irq_release = platform_get_irq_byname(pdev, "release");
> +	if (irq_release < 0) {
> +		dev_err(&pdev->dev, "No IRQ for 'release', error=%d\n",
> +			irq_release);
> +		return irq_release;
> +	}
> +
> +	button = devm_kzalloc(&pdev->dev, sizeof(*button),
> +			      GFP_KERNEL);
> +	if (!button)
> +		return -ENOMEM;
> +
> +	input = devm_input_allocate_device(&pdev->dev);
> +	if (!input)
> +		return -ENOMEM;
> +
> +	button->idev = input;
> +	button->irq_press = irq_press;
> +	button->irq_release = irq_release;
> +
> +	input->name = "NI Ettus Research USRP E3x0 Button Driver";
> +	input->phys = "e3x0_button/input0";
> +	input->dev.parent = &pdev->dev;
> +
> +	input_set_capability(input, EV_KEY, KEY_POWER);
> +
> +	error = devm_request_irq(&pdev->dev, button->irq_press,
> +					     e3x0_button_handler, 0,
> +					     "e3x0-button", button);
> +	if (error < 0) {
> +		dev_err(&pdev->dev, "Failed to request 'press' IRQ#%d: %d\n",
> +			button->irq_press, error);
> +		return error;
> +	}
> +
> +	error = devm_request_irq(&pdev->dev, button->irq_release,
> +					     e3x0_button_handler, 0,
> +					     "e3x0-button", button);
> +	if (error < 0) {
> +		dev_err(&pdev->dev, "Failed to request 'release' IRQ#%d: %d\n",
> +			button->irq_release, error);
> +		return error;
> +	}
> +
> +	error = input_register_device(button->idev);
> +	if (error) {
> +		dev_err(&pdev->dev, "Can't register input device: %d\n", error);
> +		return error;
> +	}
> +
> +	platform_set_drvdata(pdev, button);
> +	return 0;
> +}
> +
> +#ifdef CONFIG_OF
> +static const struct of_device_id e3x0_button_match[] = {
> +	{ .compatible = "ettus,e3x0-button", },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, e3x0_button_match);
> +#endif
> +
> +static struct platform_driver e3x0_button_driver = {
> +	.driver		= {
> +		.name	= "e3x0-button",
> +		.owner	= THIS_MODULE,

No need to set up owner explicitly - it is down automatically.

> +		.of_match_table = of_match_ptr(e3x0_button_match),
> +	},
> +	.probe		= e3x0_button_probe,
> +};
> +
> +static int __init e3x0_button_init(void)
> +{
> +	pr_info("e3x0-button: Copyright (c) 2014 National Instruments Corp");

Let's drop this message and use module_platform_driver() instead of
custom init/exit implementations.

> +	return platform_driver_register(&e3x0_button_driver);
> +}
> +
> +static void e3x0_button_exit(void)
> +{
> +	platform_driver_unregister(&e3x0_button_driver);
> +}
> +
> +module_init(e3x0_button_init);
> +module_exit(e3x0_button_exit);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
> +MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver");
> +MODULE_ALIAS("platform:e3x0-button");
> -- 
> 1.9.3
> 

By the way, don't you need to set up this device as a wakeup source?

Thanks.

-- 
Dmitry