[PATCH] i2c-mpc: use the cell-index property to enumerate the I2C adapters
Scott Wood
scottwood at freescale.com
Fri Dec 2 05:41:40 EST 2011
On 12/01/2011 11:33 AM, Timur Tabi wrote:
> An I2C device tree node can contain a 'cell-index' property that can be
> used to enumerate the I2C devices. If such a property exists, use it
> to specify the I2C adapter number.
Didn't we decide a long time ago that this was a bad idea?
> This feature is necessary for the Freescale PowerPC audio drivers (e.g.
> on the P1022DS). The "machine driver" needs to know the adapter number
> for each I2C adapter, but it only has access to the device tree.
> Previously, the I2C nodes always appeared in cell-index order, so the
> dynamic numbering coincided with the cell-index property. With commit
> ab827d97 ("powerpc/85xx: Rework P1022DS device tree"), the I2C nodes are
> unintentionally reversed in the device tree, and so the machine driver
> guesses the wrong I2C adapter number.
What specifically do you need this number for? What does it represent?
-Scott
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