]On Sat, Sep 7, 2019 at 5:35 PM Stephen Boyd [off-list ref] wrote:

Quoting Dong Aisheng (2019-08-20 04:13:22)

quoted

Add parsing clocks from device tree.

Please describe some more here.

Will improve.

quoted

+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(base))
+               return PTR_ERR(base);
+
+       count = of_property_count_u32_elems(np, "clock-indices");
+       if (count < 0) {
+               dev_err(&pdev->dev, "failed to count clocks\n");
+               return -EINVAL;
+       }

Is 'count' expected to be equal to IMX_LPCG_MAX_CLKS? Because later on
in this function we set the num of clks to the MAX instead of the count
from clock-indices.

No. Here is a tricky to ease the clk getting.
For example, one LPCG supports up to 8 clock outputs which each of them
is fixed to 4 bits. Then we can easily use the bit-offset/clk-indices
parsed from DT
to fetch the corresponding clock by hws[clkspec->args[0] / 4].
And the cost is very limited with only a few pointers.

quoted

+
+       clk_data = devm_kzalloc(&pdev->dev, struct_size(clk_data, hws, IMX_LPCG_MAX_CLKS),

This line is too long.

Will improve.

quoted

+                               GFP_KERNEL);
+       if (!clk_data)
+               return -ENOMEM;
+
+       clk_data->num = IMX_LPCG_MAX_CLKS;
+       clk_hws = clk_data->hws;
+
+       ret = of_property_read_u32_array(np, "clock-indices", bit_offset,
+                                        count);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "failed to read clocks bit-offset\n");

This isn't called bit-offset anymore.

Will improve.

quoted

+               return -EINVAL;
+       }
+
+       ret = of_clk_parent_fill(np, parent_names, count);
+       if (ret != count) {
+               dev_err(&pdev->dev, "failed to get clock parent names\n");
+               return -EINVAL;

return count?

Okay

Regards
Aisheng

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