On Sat, 6 Jun 2009, Hans Verkuil wrote:
> For video4linux we sometimes need to probe for a single i2c address.
> Normally you would do it like this:
>
> static const unsigned short addrs[] = {
> addr, I2C_CLIENT_END
> };
>
> client = i2c_new_probed_device(adapter, &info, addrs);
>
> This is a bit awkward and I came up with this macro:
>
> #define V4L2_I2C_ADDRS(addr, addrs...) \
> ((const unsigned short []){ addr, ## addrs, I2C_CLIENT_END })
>
> This can construct a list of one or more i2c addresses on the fly. But this
> is something that really belongs in i2c.h, renamed to I2C_ADDRS.
>
> With this macro we can just do:
>
> client = i2c_new_probed_device(adapter, &info, I2C_ADDRS(addr));
>
> Comments?
I agree it's better placed with i2c.h. It's also possible to come up with
a more syntax more variadic function like, which can be called like this:
i2c_new_probed_device(adapter, &info, addr1);
i2c_new_probed_device(adapter, &info, addr1, addr2);
Using a macro like this...
#define i2c_new_probed_device(adap,info,addr,addrs...) ({ \
const unsigned short _addrs[] = {addr, ## addrs, I2C_CLIENT_END }; \
_i2c_new_probed_device(adap, info, _addrs); })
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
