Subject: [PATCH v2 1/5] ARM: PXA: Add z2-usb-switch driver

From: [email-masked] (Marek Vasut)
Date: Sun, 28 Oct 2012 22:57:48 +0100

Dear Vasily Khoruzhick,

> This driver controls mode of USB port #2 pins - device or host.

Please supply proper commit message. This short message describes nothing.

[...]

> @@ -0,0 +1,100 @@
> +/*
> + * USB mode switcher for Z2
> + *
> + * Copyright (c) 2011 Vasily Khoruzhick

2012

> + * 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.
> + *
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/delay.h>
> +
> +#include <mach/pxa27x.h>
> +#include <mach/pxa27x-udc.h>
> +
> +#include <asm/io.h>
> +
> +#define MIN(a, b) ((a) < (b) ? (a) : (b))

min() is already defined in kernel.h

> +static ssize_t usb_mode_show(struct device *dev, struct device_attribute
> *attr, +	char *buf)
> +{
> +	if (UP2OCR & UP2OCR_HXS)
> +		return sprintf(buf, "host\n");
> +	else
> +		return sprintf(buf, "device\n");
> +}
> +
> +static ssize_t usb_mode_set(struct device *dev, struct device_attribute
> *attr, +	const char *buf, size_t count)
> +{
> +	if (strncmp(buf, "host", MIN(count, 4)) == 0) {
> +		UP2OCR = UP2OCR_HXS | UP2OCR_HXOE | UP2OCR_DPPDE | UP2OCR_DMPDE;
> +		return count;
> +	} else if (strncmp(buf, "device", MIN(count, 6)) == 0) {
> +		UP2OCR = UP2OCR_HXOE | UP2OCR_DPPUE;
> +		return count;
> +	}
> +	return -EINVAL;
> +}
> +
> +static DEVICE_ATTR(usb_mode, 0644, usb_mode_show, usb_mode_set);

I wonder if we have no better means to control enforcement of mode.

> +static const struct attribute *attrs[] = {
> +	&dev_attr_usb_mode.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group attr_group = {
> +	.attrs	= (struct attribute **)attrs,
> +};

Isn't there some macro to do this assignment?

> +static int z2_usb_switch_probe(struct platform_device *dev)

Missing __devinit

> +{
> +	int res;
> +
> +	res = sysfs_create_group(&dev->dev.kobj, &attr_group);
> +	if (res)
> +		return res;
> +
> +	UP2OCR = UP2OCR_HXOE | UP2OCR_DPPUE;
> +
> +	return 0;
> +}
> +
> +static int __devexit z2_usb_switch_remove(struct platform_device *dev)
> +{
> +	UP2OCR = UP2OCR_HXOE;
> +	sysfs_remove_group(&dev->dev.kobj, &attr_group);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver z2_usb_switch_driver = {
> +	.probe = z2_usb_switch_probe,
> +	.remove = __devexit_p(z2_usb_switch_remove),
> +
> +	.driver = {
> +		.name = "z2-usb-switch",
> +		.owner = THIS_MODULE,
> +	},
> +};
> +
> +
> +static int __init z2_usb_switch_init(void)
> +{
> +	return platform_driver_register(&z2_usb_switch_driver);
> +}
> +
> +static void __exit z2_usb_switch_exit(void)
> +{
> +	platform_driver_unregister(&z2_usb_switch_driver);
> +}
> +
> +module_init(z2_usb_switch_init);
> +module_exit(z2_usb_switch_exit);

module_platform_driver()

Best regards,
Marek Vasut