On 05/27, Sudeep Holla wrote:
+
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/scpi_protocol.h>
+
+struct scpi_clk {
+ u32 id;
+ const char *name;
+ struct clk_hw hw;
+ struct scpi_dvfs_info *info;
+ unsigned long rate_min;
+ unsigned long rate_max;
+};
+
+#define to_scpi_clk(clk) container_of(clk, struct scpi_clk, hw)
+
+static struct scpi_ops *scpi_ops;
Why do we need this singleton? Can we put this pointer into scpi_clk?
+
+static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct scpi_clk *clk = to_scpi_clk(hw);
+
+ return scpi_ops->clk_get_val(clk->id);
+}
+
+static long scpi_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct scpi_clk *clk = to_scpi_clk(hw);
+
+ if (WARN_ON(clk->rate_min && rate < clk->rate_min))
+ rate = clk->rate_min;
+ if (WARN_ON(clk->rate_max && rate > clk->rate_max))
+ rate = clk->rate_max;
+
+ return rate;
+}
Hm.. this seems really generic. It might be better to support a
way to tell the framework to limit the min/max rate that's
accepted for a clk. That could be done later though.
+[..]
+static int scpi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct scpi_clk *clk = to_scpi_clk(hw);
+
+ return scpi_ops->clk_set_val(clk->id, rate);
+}
+
+
+static int scpi_clk_add(struct device *dev, struct device_node *np)
+{
+ struct clk **clks;
+ int idx, count;
+ struct clk_onecell_data *clk_data;
+
+ count = of_property_count_strings(np, "clock-output-names");
+ if (count < 0) {
+ dev_err(dev, "%s: invalid clock output count\n", np->name);
+ return -EINVAL;
+ }
+
+ clk_data = devm_kmalloc(dev, sizeof(*clk_data), GFP_KERNEL);
+ if (!clk_data)
+ return -ENOMEM;
+
+ clks = devm_kcalloc(dev, count, sizeof(*clks), GFP_KERNEL);
+ if (!clks)
+ return -ENOMEM;
+
+ for (idx = 0; idx < count; idx++) {
+ struct scpi_clk *sclk;
+ u32 val;
+
+ sclk = devm_kzalloc(dev, sizeof(*sclk), GFP_KERNEL);
+ if (!sclk)
+ return -ENOMEM;
+
+ if (of_property_read_string_index(np, "clock-output-names",
+ idx, &sclk->name)) {
+ dev_err(dev, "invalid clock name @ %s\n", np->name);
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_index(np, "clock-indices",
+ idx, &val)) {
+ dev_err(dev, "invalid clock index @ %s\n", np->name);
+ return -EINVAL;
+ }
+
+ sclk->id = val;
+
+ clks[idx] = scpi_clk_ops_init(dev, np, sclk);
+ if (IS_ERR_OR_NULL(clks[idx]))
+ dev_err(dev, "failed to register clock '%s'\n",
+ sclk->name);
+ else
+ dev_dbg(dev, "Registered clock '%s'\n", sclk->name);
+ }
+
+ clk_data->clks = clks;
+ clk_data->clk_num = idx;
+ of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
And if of_clk_add_provider() fails?