[PATCH v2 1/1] rc: Add support for GPIO based IR Receiver driver.
From: James Hogan <hidden>
Date: 2012-02-20 20:29:39
Also in:
linux-arm-msm, linux-media, lkml
On Mon, Feb 20, 2012 at 03:17:52PM +0530, Ravi Kumar V wrote:
quoted hunk ↗ jump to hunk
Adds GPIO based IR Receiver driver. It decodes signals using decoders available in rc framework. Signed-off-by: Ravi Kumar V <redacted> --- drivers/media/rc/Kconfig | 9 ++ drivers/media/rc/Makefile | 1 + drivers/media/rc/gpio-ir-recv.c | 189 +++++++++++++++++++++++++++++++++++++++ include/media/gpio-ir-recv.h | 23 +++++ 4 files changed, 222 insertions(+), 0 deletions(-) create mode 100644 drivers/media/rc/gpio-ir-recv.c create mode 100644 include/media/gpio-ir-recv.hdiff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig index aeb7f43..6f63ded 100644 --- a/drivers/media/rc/Kconfig +++ b/drivers/media/rc/Kconfig@@ -256,4 +256,13 @@ config RC_LOOPBACK To compile this driver as a module, choose M here: the module will be called rc_loopback. +config IR_GPIO_CIR + tristate "GPIO IR remote control" + depends on RC_CORE + ---help--- + Say Y if you want to use GPIO based IR Receiver. + + To compile this driver as a module, choose M here: the module will + be called gpio-ir-recv. + endif #RC_COREdiff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile index 2156e78..9b3568e 100644 --- a/drivers/media/rc/Makefile +++ b/drivers/media/rc/Makefile@@ -25,3 +25,4 @@ obj-$(CONFIG_IR_REDRAT3) += redrat3.o obj-$(CONFIG_IR_STREAMZAP) += streamzap.o obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o +obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.odiff --git a/drivers/media/rc/gpio-ir-recv.c b/drivers/media/rc/gpio-ir-recv.c new file mode 100644 index 0000000..cf6e7f6 --- /dev/null +++ b/drivers/media/rc/gpio-ir-recv.c@@ -0,0 +1,189 @@ +/* Copyright (c) 2012, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only 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. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/irq.h> +#include <media/rc-core.h> +#include <media/gpio-ir-recv.h> + +#define GPIO_IR_DRIVER_NAME "gpio-rc-recv" +#define GPIO_IR_DEVICE_NAME "gpio_ir_recv" + +struct gpio_rc_dev { + struct rc_dev *rcdev; + struct mutex lock;
I could be completely wrong here, but is this lock necessary since data is only read, and it's only used by a single interrupt handler?
+ unsigned int gpio_nr;
+ bool active_low;
+ bool can_wakeup;
+};
+
+static irqreturn_t gpio_ir_recv_irq(int irq, void *dev_id)
+{
+ struct gpio_rc_dev *gpio_dev = dev_id;
+ unsigned int gval;
+ int rc = 0;
+ enum raw_event_type type = IR_SPACE;
+
+ mutex_lock(&gpio_dev->lock);
+ gval = gpio_get_value_cansleep(gpio_dev->gpio_nr);
+
+ if (gval < 0)
+ goto err_get_value;
+
+ if (gpio_dev->active_low)
+ gval = !gval;
+
+ if (gval == 1)
+ type = IR_PULSE;
+
+ rc = ir_raw_event_store_edge(gpio_dev->rcdev, type);
+ if (rc < 0)
+ goto err_get_value;Since ir_raw_event_store_edge just puts the event into a kfifo for the ir-raw thread to handle, does this really have to be a threaded IRQ? I'd have thought you'd get more accurate time measurements (especially on slower/embedded CPUs) if the IRQ is serviced as soon as possible. If it needs to be threaded so that the gpio read can sleep, perhaps it could make use of a hard irq if the gpio can be accessed atomically, and fall back to threaded if not.
+
+ ir_raw_event_handle(gpio_dev->rcdev);
+
+err_get_value:
+ mutex_unlock(&gpio_dev->lock);
+
+ return IRQ_HANDLED;
+}
+
+static int __devinit gpio_ir_recv_probe(struct platform_device *pdev)
+{
+ struct gpio_rc_dev *gpio_dev;
+ struct rc_dev *rcdev;
+ const struct gpio_ir_recv_platform_data *pdata =
+ pdev->dev.platform_data;
+ int rc;
+
+ if (!pdata)
+ return -EINVAL;
+
+ if (pdata->gpio_nr < 0)
+ return -EINVAL;
+
+ gpio_dev = kzalloc(sizeof(struct gpio_rc_dev), GFP_KERNEL);
+ if (!gpio_dev)
+ return -ENOMEM;
+
+ mutex_init(&gpio_dev->lock);
+
+ rcdev = rc_allocate_device();
+ if (!rcdev) {
+ rc = -ENOMEM;
+ goto err_allocate_device;
+ }
+
+ rcdev->driver_type = RC_DRIVER_IR_RAW;
+ rcdev->allowed_protos = RC_TYPE_NEC;Is this necessary, since the driver is protocol agnostic?
+ rcdev->input_name = GPIO_IR_DEVICE_NAME;
+ rcdev->input_id.bustype = BUS_HOST;
+ rcdev->driver_name = GPIO_IR_DRIVER_NAME;
+ rcdev->map_name = RC_MAP_EMPTY;
+
+ gpio_dev->rcdev = rcdev;
+ gpio_dev->gpio_nr = pdata->gpio_nr;
+ gpio_dev->active_low = pdata->active_low;
+ gpio_dev->can_wakeup = pdata->can_wakeup;
+
+
+ rc = gpio_request(pdata->gpio_nr, "gpio-ir-recv");
+ if (rc < 0)
+ goto err_gpio_request;
+ rc = gpio_direction_input(pdata->gpio_nr);
+ if (rc < 0)
+ goto err_gpio_direction_input;
+
+ rc = rc_register_device(rcdev);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "failed to register rc device\n");
+ goto err_register_rc_device;
+ }
+
+ platform_set_drvdata(pdev, gpio_dev);
+
+ rc = request_threaded_irq(gpio_to_irq(pdata->gpio_nr),
+ NULL, gpio_ir_recv_irq,
+ IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+ "gpio-ir-recv-irq", gpio_dev);
+ if (rc < 0)
+ goto err_request_irq;
+
+ if (pdata->can_wakeup == true) {
+ rc = enable_irq_wake(gpio_to_irq(pdata->gpio_nr));
+ if (rc < 0)
+ goto err_enable_irq_wake;would this be better done in a suspend/resume callback, along with device_may_wakeup and device_set_wakeup_capable/device_init_wakeup so that it can be enabled and disabled with sysfs? Cheers James
quoted hunk ↗ jump to hunk
+ } + + return 0; + +err_enable_irq_wake: + free_irq(gpio_to_irq(gpio_dev->gpio_nr), gpio_dev); +err_request_irq: + platform_set_drvdata(pdev, NULL); + rc_unregister_device(rcdev); +err_register_rc_device: +err_gpio_direction_input: + gpio_free(pdata->gpio_nr); +err_gpio_request: + rc_free_device(rcdev); + rcdev = NULL; +err_allocate_device: + mutex_destroy(&gpio_dev->lock); + kfree(gpio_dev); + return rc; +} + +static int __devexit gpio_ir_recv_remove(struct platform_device *pdev) +{ + struct gpio_rc_dev *gpio_dev = platform_get_drvdata(pdev); + + disable_irq_wake(gpio_to_irq(gpio_dev->gpio_nr)); + free_irq(gpio_to_irq(gpio_dev->gpio_nr), gpio_dev); + platform_set_drvdata(pdev, NULL); + rc_unregister_device(gpio_dev->rcdev); + gpio_free(gpio_dev->gpio_nr); + rc_free_device(gpio_dev->rcdev); + mutex_destroy(&gpio_dev->lock); + kfree(gpio_dev); + return 0; +} + +static struct platform_driver gpio_ir_recv_driver = { + .probe = gpio_ir_recv_probe, + .remove = __devexit_p(gpio_ir_recv_remove), + .driver = { + .name = GPIO_IR_DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init gpio_ir_recv_init(void) +{ + return platform_driver_register(&gpio_ir_recv_driver); +} +module_init(gpio_ir_recv_init); + +static void __exit gpio_ir_recv_exit(void) +{ + platform_driver_unregister(&gpio_ir_recv_driver); +} +module_exit(gpio_ir_recv_exit); + +MODULE_DESCRIPTION("GPIO IR Receiver driver"); +MODULE_LICENSE("GPL v2");diff --git a/include/media/gpio-ir-recv.h b/include/media/gpio-ir-recv.h new file mode 100644 index 0000000..3eab611 --- /dev/null +++ b/include/media/gpio-ir-recv.h@@ -0,0 +1,23 @@ +/* Copyright (c) 2012, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only 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. + */ + +#ifndef __GPIO_IR_RECV_H__ +#define __GPIO_IR_RECV_H__ + +struct gpio_ir_recv_platform_data { + unsigned int gpio_nr; + bool active_low; + bool can_wakeup; +}; + +#endif /* __GPIO_IR_RECV_H__ */ +-- Sent by a consultant of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/