Re: [PATCH 1/2] firmware: Google VPD: import lib_vpd source files

[Greg Kroah-Hartman]

On Tue, Apr 11, 2017 at 11:14:30AM +0200, Thierry Escande wrote:
> From: Wei-Ning Huang <wnhuang@xxxxxxxxxx>
> 
> This patch imports lib_vpd.h and vpd_decode.c from the Chromium Vital
> Product Data project.
> 
> This library is used to parse VPD sections obtained from coreboot table
> entries describing Chromebook devices product data. Only the sections of
> type VPD_TYPE_STRING are decoded.
> 
> The VPD string sections in the coreboot tables contain the type (1 byte
> set to 0x01 for strings), the key length, the key ascii array, the value
> length, and the value ascii array. The key and value arrays are not null
> terminated.
> 
> Signed-off-by: Wei-Ning Huang <wnhuang@xxxxxxxxxx>
> Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
> ---
>  drivers/firmware/google/vpd_decode.c | 99 ++++++++++++++++++++++++++++++++++++
>  drivers/firmware/google/vpd_decode.h | 59 +++++++++++++++++++++
>  2 files changed, 158 insertions(+)
>  create mode 100644 drivers/firmware/google/vpd_decode.c
>  create mode 100644 drivers/firmware/google/vpd_decode.h
> 
> diff --git a/drivers/firmware/google/vpd_decode.c b/drivers/firmware/google/vpd_decode.c
> new file mode 100644
> index 0000000..75e4027
> --- /dev/null
> +++ b/drivers/firmware/google/vpd_decode.c
> @@ -0,0 +1,99 @@
> +/*
> + * vpd_decode.c
> + *
> + * Google VPD decoding routines.
> + *
> + * Copyright 2017 Google Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License v2.0 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/export.h>
> +
> +#include "vpd_decode.h"
> +
> +static int decode_len(const int32_t max_len, const uint8_t *in,
> +		      int32_t *length, int32_t *decoded_len)
> +{
> +	uint8_t more;
> +	int i = 0;
> +
> +	if (!length || !decoded_len)
> +		return VPD_FAIL;
> +
> +	*length = 0;
> +	do {
> +		if (i >= max_len)
> +			return VPD_FAIL;
> +
> +		more = in[i] & 0x80;
> +		*length <<= 7;
> +		*length |= in[i] & 0x7f;
> +		++i;
> +	} while (more);
> +
> +	*decoded_len = i;
> +
> +	return VPD_OK;
> +}
> +
> +int decode_vpd_string(const int32_t max_len, const uint8_t *input_buf,
> +		      int32_t *consumed, vpd_decode_callback callback,
> +		      void *callback_arg)
> +{
> +	int type;
> +	int res;
> +	int32_t key_len, value_len;
> +	int32_t decoded_len;
> +	const uint8_t *key, *value;
> +
> +	/* type */
> +	if (*consumed >= max_len)
> +		return VPD_FAIL;
> +
> +	type = input_buf[*consumed];
> +
> +	switch (type) {
> +	case VPD_TYPE_INFO:
> +	case VPD_TYPE_STRING:
> +		(*consumed)++;
> +
> +		/* key */
> +		res = decode_len(max_len - *consumed, &input_buf[*consumed],
> +				 &key_len, &decoded_len);
> +		if (res != VPD_OK || *consumed + decoded_len >= max_len)
> +			return VPD_FAIL;
> +
> +		*consumed += decoded_len;
> +		key = &input_buf[*consumed];
> +		*consumed += key_len;
> +
> +		/* value */
> +		res = decode_len(max_len - *consumed, &input_buf[*consumed],
> +				 &value_len, &decoded_len);
> +		if (res != VPD_OK || *consumed + decoded_len > max_len)
> +			return VPD_FAIL;
> +
> +		*consumed += decoded_len;
> +		value = &input_buf[*consumed];
> +		*consumed += value_len;
> +
> +		if (type == VPD_TYPE_STRING)
> +			return callback(key, key_len, value, value_len,
> +					callback_arg);
> +		break;
> +
> +	default:
> +		return VPD_FAIL;
> +	}
> +
> +	return VPD_OK;
> +}
> +EXPORT_SYMBOL(decode_vpd_string);

Normally put the prefix for the driver you are exporting from:
	vpd_string_decode()?

And EXPORT_SYMBOL_GPL() perhaps?

thanks,

greg k-h