Re: [RFC PATCH 01/06] input/rmi4: Public header and documentation

From: Dmitry Torokhov
Date: Thu Oct 11 2012 - 04:20:51 EST


On Fri, Oct 05, 2012 at 09:09:58PM -0700, Christopher Heiny wrote:
> +
> + int (*write_block)(struct rmi_phys_device *phys, u16 addr, u8 *buf,
> + int len);
> + int (*read_block)(struct rmi_phys_device *phys, u16 addr, u8 *buf,
> + int len);
> +

If you declare your buffer as [const] void * instead of u8 * I think you
will be able to get rid of most of your unions.

> +
> +/**
> + * Helper fn to convert a byte array representing a 16 bit value in the RMI
> + * endian-ness to a 16-bit value in the native processor's specific endianness.
> + * We don't use ntohs/htons here because, well, we're not dealing with
> + * a pair of 16 bit values. Casting dest to u16* wouldn't work, because
> + * that would imply knowing the byte order of u16 in the first place. The
> + * same applies for using shifts and masks.
> + */
> +static inline u16 batohs(u8 *src)
> +{
> + return src[1] * 0x100 + src[0];
> +}
> +
> +/**
> + * Helper function to convert a 16 bit value (in host processor endianess) to
> + * a byte array in the RMI endianess for u16s. See above comment for
> + * why we dont us htons or something like that.
> + */
> +static inline void hstoba(u8 *dest, u16 src)
> +{
> + dest[0] = src % 0x100;
> + dest[1] = src / 0x100;
> +}

These are not used anymore, right?

--
Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/