Re: [RFC PATCH 01/06] input/rmi4: Public header and documentation
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2012-10-11 08:20:59
Also in:
lkml
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