On Sat, Nov 26, 2011 at 5:48 AM, Shawn Guo [off-list ref] wrote:

On Mon, Nov 21, 2011 at 05:40:46PM -0800, Mike Turquette wrote:

quoted

Many platforms support simple gateable clks and fixed-rate clks that
should not be re-implemented by every platform.

This patch introduces a gateable clk with a common programming model of
gate control via a write of 1 bit to a register. ?Both set-to-enable and
clear-to-enable are supported.

Also introduced is a fixed-rate clk which has no reprogrammable aspects.

The purpose of both types of clks is documented in drivers/clk/basic.c.

What I have seen is drivers/clk/clk-basic.c.

Will fix in v4.

quoted

+int clk_register_gate(struct device *dev, const char *name, unsigned long flags,
+ ? ? ? ? ? ? struct clk *fixed_parent, void __iomem *reg, u8 bit_idx,
+ ? ? ? ? ? ? int set_to_enable)
+{
+ ? ? struct clk_hw_gate *gclk;
+ ? ? struct clk *clk;
+
+ ? ? gclk = kmalloc(sizeof(struct clk_hw_gate), GFP_KERNEL);
+
+ ? ? if (!gclk) {
+ ? ? ? ? ? ? pr_err("%s: could not allocate gated clk\n", __func__);
+ ? ? ? ? ? ? return -ENOMEM;
+ ? ? }
+
+ ? ? clk = &gclk->clk;
+
+ ? ? /* struct clk_hw_gate assignments */
+ ? ? gclk->fixed_parent = fixed_parent;
+ ? ? gclk->reg = reg;
+ ? ? gclk->bit_idx = bit_idx;
+
+ ? ? /* struct clk assignments */
+ ? ? clk->name = name;
+ ? ? clk->flags = flags;
+
+ ? ? if (set_to_enable)
+ ? ? ? ? ? ? clk->ops = &clk_hw_gate_set_enable_ops;
+ ? ? else
+ ? ? ? ? ? ? clk->ops = &clk_hw_gate_set_disable_ops;
+
+ ? ? clk_init(NULL, clk);
+
+ ? ? return 0;

The device tree support needs to get this 'struct clk *', so we may
want to have all these registering functions return the 'clk'.

Thanks for the input.  Truthfully I'm very DT-ignorant so I'm happy to
reshape any APIs for that topic.  Hope to fix that soon.

Thanks for reviewing,
Mike