Message-ID: <1429578297.4216.43.camel@perches.com>
Subject: Re: [PATCH 1/2] firewire: firewire is a big-endian bus
From: Joe Perches <joe@perches.com>
To: Laurent Vivier <laurent@vivier.eu>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>,
        linux1394-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org
Date: Mon, 20 Apr 2015 18:04:57 -0700
In-Reply-To: <1429576576-1637-2-git-send-email-laurent@vivier.eu>
References: <1429576576-1637-1-git-send-email-laurent@vivier.eu>
	 <1429576576-1637-2-git-send-email-laurent@vivier.eu>
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On Tue, 2015-04-21 at 02:36 +0200, Laurent Vivier wrote:
> So, dump config_rom data as big-endian values.
> 
> The value given by /sys/bus/firewire/devices/fw0 were correctly
> given on a big-endian host (like powermac) not on a little-endian host
> (like PC), for instance:
[]
> diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
[]
> @@ -399,14 +399,14 @@ static ssize_t config_rom_show(struct device *dev,
>  			       struct device_attribute *attr, char *buf)
>  {
>  	struct fw_device *device = fw_device(dev);
> -	size_t length;
> +	size_t i;
>  
>  	down_read(&fw_device_rwsem);
> -	length = device->config_rom_length * 4;
> -	memcpy(buf, device->config_rom, length);
> +	for (i = 0; i < device->config_rom_length; i++)
> +		((u32 *)buf)[i] = be32_to_cpu(device->config_rom[i]);

Is buf guaranteed to be appropriately aligned on a u32?


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