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Date: Mon, 25 Jan 2010 16:15:09 +0100
From: Wolfram Sang <w.sang@pengutronix.de>
To: Wolfgang Grandegger <wg@grandegger.com>
Subject: Re: [PATCH 2/3] i2c-mpc: add support for the MPC512x processors
	from Freescale
Message-ID: <20100125151509.GD5257@pengutronix.de>
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> >> =20
> >> -static void __devinit mpc_i2c_setclock_52xx(struct device_node *node,
> >> -					    struct mpc_i2c *i2c,
> >> -					    u32 clock, u32 prescaler)
> >> +static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
> >> +					 struct mpc_i2c *i2c,
> >> +					 u32 clock, u32 prescaler)
> >>  {
> >>  	int ret, fdr;
> >> =20
> >> +	if (clock =3D=3D -1) {
> >=20
> > Could we use 0 for 'no_clock'? This would make the above statement simp=
ly
>=20
> "0" is already used to maintain backward compatibility setting a safe
> divider.

Ah, now I see:

'clock =3D=3D -1' means 'preserve clocks' (and is checked here in mpc_i2c_s=
etup_52xx())
'clock =3D=3D  0' means 'safe divider' (and is checked in mpc_i2c_get_fdr_5=
2xx())

This is not a beauty ;)

What about adding a flags variable to the setup-functions?

Regards,

   Wolfram

--=20
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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