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Date: Mon, 19 Jul 2021 17:15:16 +0200
From: Andrew Lunn <andrew@lunn.ch>
To: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>,
	Wedson Almeida Filho <wedsonaf@google.com>,
	Greg KH <greg@kroah.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	Kees Cook <keescook@chromium.org>, Jan Kara <jack@suse.cz>,
	James Bottomley <James.Bottomley@hansenpartnership.com>,
	Julia Lawall <julia.lawall@inria.fr>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Roland Dreier <roland@kernel.org>, ksummit@lists.linux.dev,
	Viresh Kumar <viresh.kumar@linaro.org>
Subject: Re: [TECH TOPIC] Rust for Linux
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> For instance, the driver developer could write something like this
> right in the Rust source code:
> 
>     memory_map!(
>         0x0042  simple_value  2  value(u16)
>         0x0044  some_flags    2  flags(..., FLAG1, FLAG2)
>         0x0046  custom_type   1  value(MyCustomType)
>         0x0047  across_bits   2  [
>                                    0..2  other_flags  flags(FOO, BAR),
>                                    2..4  _            unused,
>                                    4..31 temp         value(Temperature),
>                                  ]
>     );
> 
> And then simply call:
> 
>     driver.map.read_temp()
> 
> and it would automatically perform the shifting, masking, unit
> conversions, etc. to get the raw sensor data into a value in proper
> Kelvin.

Hi Miguel

Can you express endianness here as well? There are often cases where
the hardware is always big endian independent of the CPU
endianness. Some of the readl/writel macros handle this, adding a swap
when the two don't match.

     Andrew