Subject: [PATCH v3 1/1] rc: Add support for GPIO based IR Receiver driver.

From: [email-masked] (Ravi Kumar V)
Date: Tue, 12 Jun 2012 18:26:05 +0530

On 4/24/2012 1:41 AM, Jarod Wilson wrote:
> On Tue, Feb 28, 2012 at 11:21:40AM +0530, Ravi Kumar V wrote:
>> Adds GPIO based IR Receiver driver. It decodes signals using decoders
>> available in rc framework.
>
> Been meaning to look at this, but it looks like its already merged
> upstream. Just one question though, inlined below.
>
>> --- /dev/null
>> +++ b/drivers/media/rc/gpio-ir-recv.c
>> @@ -0,0 +1,205 @@
>> +/* 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;
>> +	unsigned int gpio_nr;
>> +	bool active_low;
>> +};
>> +
>> +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;
>> +
>> +	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;
>
> What happens if gval is>  1?

gpio_get_value_cansleep() can return
bool for low/high.
negative for error.

so i think we dont get value> 1

>
>> +	rc = ir_raw_event_store_edge(gpio_dev->rcdev, type);
>> +	if (rc<  0)
>> +		goto err_get_value;
>> +
>> +	ir_raw_event_handle(gpio_dev->rcdev);
>> +
>> +err_get_value:
>> +	return IRQ_HANDLED;
>> +}
>
> Looks like you'll store a space any time you get gval>  1, which may or
> may not be intended here...
>
>

-- 
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.