On 10/12/2013 05:32 AM, Thierry Reding wrote:
On Fri, Oct 11, 2013 at 04:14:27PM -0600, Stephen Warren wrote:
On 10/07/2013 02:34 AM, Thierry Reding wrote:
From: Mikko Perttunen mperttunen@nvidia.com
The Tegra114 display controller is backwards-compatible with previous generations of the Tegra SoC. No code changes are required.
If the HW is backwards-compatible, then there's no need to add extra compatible values to the driver; just write the following in the DT, and it'll just work:
compatible = "nvidia,tegra114-dc", "nvidia,tegra30-dc";
One reason why I thought it might be useful to still include this, even though unnecessary, was to match it to the host1x_drm_subdevs table. We can probably remove the entry from there as well, though.
As far as I can tell, the same holds for Tegra30, which is also backwards compatible with Tegra20 but the DTS doesn't contain the Tegra20 compatible. So to keep ABI compatibility we'll need to keep the nvidia,tegra30-dc in the driver's match tables, but I could still update the DTS to include the nvidia,tegra20-dc for correctness.
Does that make sense?
Yes, fixing the Tegra30 .dtsi file sounds like a good idea.