Re: [PATCH V3 3/3] ARM: clk-imx6q: Add missing lvds and anaclk clock to the clock tree
From: Shengjiu Wang
Date: Mon Aug 25 2014 - 03:40:43 EST
On Mon, Aug 18, 2014 at 02:06:07PM +0800, Shawn Guo wrote:
> On Mon, Aug 11, 2014 at 11:09:36AM +0800, Shengjiu Wang wrote:
> > On Sat, Aug 09, 2014 at 09:58:42PM +0800, Shawn Guo wrote:
> > > On Fri, Aug 08, 2014 at 03:02:49PM +0800, Shengjiu Wang wrote:
> > > > @@ -176,8 +182,12 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
> > > > * the "output_enable" bit as a gate, even though it's really just
> > > > * enabling clock output.
> > > > */
> > > > - clk[IMX6QDL_CLK_LVDS1_GATE] = imx_clk_gate("lvds1_gate", "lvds1_sel", base + 0x160, 10);
> > > > - clk[IMX6QDL_CLK_LVDS2_GATE] = imx_clk_gate("lvds2_gate", "lvds2_sel", base + 0x160, 11);
> > > > + clk[IMX6QDL_CLK_LVDS1_GATE] = imx_clk_gate2("lvds1_gate", "lvds1_sel", base + 0x160, 10);
> > > > + clk[IMX6QDL_CLK_LVDS2_GATE] = imx_clk_gate2("lvds2_gate", "lvds2_sel", base + 0x160, 11);
> > >
> > > I do not think you can simply change to use imx_clk_gate2() here. It's
> > > designed for those CCGR gate clocks, each of which is controlled by two
> > > bits.
> > >
> > > Shawn
> > >
> > As Lucas Stach's suggestion, we need to do add some method for mutually exclusive clock,
> > lvds1_gate with lvds1_in, lvds2_gate with lvds2_in. I add imx_clk_gate2_exclusive() function in clk-gate2.c.
> > So I change imx_clk_gate() to imx_clk_gate2() here.
> > As you said, this is not good solution.
> It's not just a "not good" solution but wrong and broken one. The net
> result of that is if you call clk_enable() on lvds1_gate, both bit 10
> and 11 will be set.
> > So I need your suggestion, how can I do?
> I guess we will need a new clock type to handle such mutually exclusive
> clocks, rather than patching clk-gate2.
Could you please help to implement this feature?
Furthermore, I'd like to drop patch 2 and patch 3, wait the implementation from
Could you please review the patch 1? do you have any comments?
> > First, is it allowable that to add imx_clk_gate2_exclusive() function, is there a more better way?
> Again, this is completely wrong.
> > second, or should I change the clk-gate.c to add exclusive control?
> If such mutually exclusive clocks are somehow common across different
> clock controllers, we can propose to change clk-gate.c for handling
> them. But I'm not sure this is a common case.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/