Re: [PATCH v7 6/7] clk: hi6220: Clock driver support for Hisilicon hi6220 SoC

From: Bintian
Date: Fri May 22 2015 - 01:24:40 EST


Hello Stephen,

On 2015/5/22 2:00, Stephen Boyd wrote:
On 05/20/15 20:57, Bintian wrote:



+
+static void __init hi6220_clk_sys_init(struct device_node *np)
+{
+ struct hisi_clock_data *clk_data;
+
+ clk_data = hisi_clk_init(np, HI6220_SYS_NR_CLKS);
+ if (!clk_data)
+ return;
+
+ hisi_clk_register_gate_sep(hi6220_separated_gate_clks_sys,
+ ARRAY_SIZE(hi6220_separated_gate_clks_sys), clk_data);
+
+ hisi_clk_register_mux(hi6220_mux_clks_sys,
+ ARRAY_SIZE(hi6220_mux_clks_sys), clk_data);
+
+ hi6220_clk_register_divider(hi6220_div_clks_sys,
+ ARRAY_SIZE(hi6220_div_clks_sys), clk_data);
+
+ if (!clk_data_ao)
+ return;
+
+ /* enable high speed clock on UART1 mux */
+ clk_set_parent(clk_data->clk_data.clks[HI6220_UART1_SRC],
+ clk_data_ao->clk_data.clks[HI6220_150M]);

Sorry I missed this one earlier. Can we do this clk_set_parent() through
assigned-parents instead?
Uart1 has two clock parents in hi6220, and use "clk_tcxo" by default,
we use uart1 to connect BT in HiKey, and switch to "clk_150m" for high
speed mode of BT, but pl011 has no code to set clock rate or set clock
parents operation, so it's a easy way to do that here.

Is pl011 the uart device? Does it have a node in DT somewhere? If it
does, then we could put the assigned-parents properties in that node so
that when the pl011 probes the uart1 clock has its parent set to
clk_150m. See the "Assigned clock parents and rates" section of
Documentation/devicetree/bindings/clock/clock-bindings.txt.

I will verify this.

If it is OK, I will remove "clk_set_parent" from this patch.

Thanks,

Bintian

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