[PATCH 06/15] drm/sun4i: tcon: Add support for tcon-top

Maxime Ripard
2018-05-21T08:07:59Z

On Sat, May 19, 2018 at 08:31:18PM +0200, Jernej Skrabec wrote:
> If SoC has TCON TOP unit, it has to be configured from TCON, since it
> has all information needed. Additionally, if it is TCON TV, it must also
> enable bus gate inside TCON TOP unit.

Why?

> Add support for such TCONs.
>
> Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
> ---
> drivers/gpu/drm/sun4i/sun4i_tcon.c | 28 ++++++++++++++++++++++++++++
> drivers/gpu/drm/sun4i/sun4i_tcon.h | 8 ++++++++
> 2 files changed, 36 insertions(+)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index 08747fc3ee71..e0c562ce1c22 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -688,6 +688,16 @@ static int sun4i_tcon_init_clocks(struct device *dev,
> dev_err(dev, "Couldn't get the TCON bus clock\n");
> return PTR_ERR(tcon->clk);
> }
> +
> + if (tcon->quirks->needs_tcon_top && tcon->quirks->has_channel_1) {
> + tcon->top_clk = devm_clk_get(dev, "tcon-top");
> + if (IS_ERR(tcon->top_clk)) {
> + dev_err(dev, "Couldn't get the TCON TOP bus clock\n");
> + return PTR_ERR(tcon->top_clk);
> + }
> + clk_prepare_enable(tcon->top_clk);
> + }
> +
> clk_prepare_enable(tcon->clk);
>
> if (tcon->quirks->has_channel_0) {
> @@ -712,6 +722,7 @@ static int sun4i_tcon_init_clocks(struct device *dev,
> static void sun4i_tcon_free_clocks(struct sun4i_tcon *tcon)
> {
> clk_disable_unprepare(tcon->clk);
> + clk_disable_unprepare(tcon->top_clk);
> }
>
> static int sun4i_tcon_init_irq(struct device *dev,
> @@ -980,6 +991,23 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
> tcon->id = engine->id;
> tcon->quirks = of_device_get_match_data(dev);
>
> + if (tcon->quirks->needs_tcon_top) {
> + struct device_node *np;
> +
> + np = of_parse_phandle(dev->of_node, "allwinner,tcon-top", 0);
> + if (np) {
> + struct platform_device *pdev;
> +
> + pdev = of_find_device_by_node(np);
> + if (pdev)
> + tcon->tcon_top = platform_get_drvdata(pdev);
> + of_node_put(np);
> +
> + if (!tcon->tcon_top)
> + return -EPROBE_DEFER;
> + }
> + }
> +

I might have missed it, but I've not seen the bindings additions for
that property. This shouldn't really be done that way anyway, instead
of using a direct phandle, you should be using the of-graph, with the
TCON-top sitting where it belongs in the flow of data.

Maxime

--
Maxime Ripard, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180521/9e6fce45/attachment.sig>