int dev_pm_opp_set_rate()

in core.c [1091:1143]

• 35 lines of code
• 7 McCabe index (conditional complexity)

int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
{
	struct opp_table *opp_table;
	unsigned long freq = 0, temp_freq;
	struct dev_pm_opp *opp = NULL;
	int ret;

	opp_table = _find_opp_table(dev);
	if (IS_ERR(opp_table)) {
		dev_err(dev, "%s: device's opp table doesn't exist\n", __func__);
		return PTR_ERR(opp_table);
	}

	if (target_freq) {
		/*
		 * For IO devices which require an OPP on some platforms/SoCs
		 * while just needing to scale the clock on some others
		 * we look for empty OPP tables with just a clock handle and
		 * scale only the clk. This makes dev_pm_opp_set_rate()
		 * equivalent to a clk_set_rate()
		 */
		if (!_get_opp_count(opp_table)) {
			ret = _generic_set_opp_clk_only(dev, opp_table->clk, target_freq);
			goto put_opp_table;
		}

		freq = clk_round_rate(opp_table->clk, target_freq);
		if ((long)freq <= 0)
			freq = target_freq;

		/*
		 * The clock driver may support finer resolution of the
		 * frequencies than the OPP table, don't update the frequency we
		 * pass to clk_set_rate() here.
		 */
		temp_freq = freq;
		opp = _find_freq_ceil(opp_table, &temp_freq);
		if (IS_ERR(opp)) {
			ret = PTR_ERR(opp);
			dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n",
				__func__, freq, ret);
			goto put_opp_table;
		}
	}

	ret = _set_opp(dev, opp_table, opp, freq);

	if (target_freq)
		dev_pm_opp_put(opp);
put_opp_table:
	dev_pm_opp_put_opp_table(opp_table);
	return ret;
}