diff --git a/drivers/opp/core.c b/drivers/opp/core.c index ba43e6a3dc0a..e4f01e7771a2 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -819,6 +819,8 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) if (unlikely(!target_freq)) { if (opp_table->required_opp_tables) { ret = _set_required_opps(dev, opp_table, NULL); + } else if (!_get_opp_count(opp_table)) { + return 0; } else { dev_err(dev, "target frequency can't be 0\n"); ret = -EINVAL; @@ -849,6 +851,18 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) goto put_opp_table; } + /* + * 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, clk, freq); + goto put_opp_table; + } + temp_freq = old_freq; old_opp = _find_freq_ceil(opp_table, &temp_freq); if (IS_ERR(old_opp)) {