Quoting Daniel Mack (2019-12-09 10:35:10)
diff --git a/drivers/clk/clk-ad242x.c b/drivers/clk/clk-ad242x.c new file mode 100644 index 000000000000..201789d8f174 --- /dev/null +++ b/drivers/clk/clk-ad242x.c @@ -0,0 +1,231 @@ +// SPDX-License-Identifier: GPL-2.0
+#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/clk.h>
Is this include used?
+#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/errno.h>
Is this include used?
+#include <linux/mfd/ad242x.h>
Any way we can avoid this build dependency? Maybe just put defines in this driver that deals with the clk bits of the device?
+#include <linux/platform_device.h> +#include <linux/regmap.h>
+#include <dt-bindings/clock/adi,ad242x.h>
+#define AD242X_NUM_CLKS 2
+struct ad242x_clk_hw {
struct clk_hw hw;struct clk_init_data init;
Do we need to keep around this init data after probe? I'd rather leave this out.
struct ad242x_node *node;
What's the point of this structure? Can we use dev->parent->regmap and just store the struct regmap pointer here instead of using this custom struct?
u8 reg;+};
+struct ad242x_clk_driver_data {
struct ad242x_clk_hw hw[AD242X_NUM_CLKS];
If this is the only drvdata, then I'd prefer just the array and not another struct so we can have clarity.
+};
+static inline struct ad242x_clk_hw *to_ad242x_clk(struct clk_hw *hw) +{
return container_of(hw, struct ad242x_clk_hw, hw);+}
[...]
+static long ad242x_clk_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)+{
unsigned long pll_rate = *parent_rate * 2048UL;unsigned long prediv, div;if (rate > pll_rate / 4 || rate < pll_rate / 1024UL)return -EINVAL;
This callback should round the rate to something valid. If the rate is larger than pll_rate / 4 then it should clamp to be the highest rate supported. Likewise for something slow.
ad242x_do_div(rate, pll_rate, &prediv, &div);return pll_rate / (prediv * div);+}
[...]
+static struct clk_hw * +ad242x_of_clk_get(struct of_phandle_args *clkspec, void *data) +{
struct ad242x_clk_driver_data *drvdata = data;unsigned int idx = clkspec->args[0];return &drvdata->hw[idx].hw;
It looks quite a bit like of_clk_hw_onecell_get(). Can that be used? Or at least check for out of bounds and return failure?
+}
+static int ad242x_clk_probe(struct platform_device *pdev) +{
const char *clk_names[AD242X_NUM_CLKS] = { "clkout1", "clkout2" };u8 regs[AD242X_NUM_CLKS] = { AD242X_CLK1CFG, AD242X_CLK2CFG };struct ad242x_clk_driver_data *drvdata;struct device *dev = &pdev->dev;const char *sync_clk_name;struct ad242x_node *node;int i, ret;if (!dev->of_node)return -ENODEV;
Please drop this. It's not useful.
drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);if (!drvdata)return -ENOMEM;node = dev_get_drvdata(dev->parent);
Add a NULL check on node?
sync_clk_name = ad242x_master_get_clk_name(node->master);for (i = 0; i < AD242X_NUM_CLKS; i++) {const char *name;if (of_property_read_string_index(dev->of_node,"clock-output-names",i, &name) == 0)drvdata->hw[i].init.name = name;elsedrvdata->hw[i].init.name = clk_names[i];
Do you need unique names? Or can you generate psuedo unique names based on the device name and clk number?
drvdata->hw[i].reg = regs[i];drvdata->hw[i].init.ops = &ad242x_clk_ops;drvdata->hw[i].init.num_parents = 1;drvdata->hw[i].init.parent_names = &sync_clk_name;drvdata->hw[i].hw.init = &drvdata->hw[i].init;drvdata->hw[i].node = node;ret = devm_clk_hw_register(dev, &drvdata->hw[i].hw);if (ret < 0)return ret;}return devm_of_clk_add_hw_provider(dev, ad242x_of_clk_get, drvdata);+}