From aca48b61f963869ccbb5cf84805a7ad68bf812cd Mon Sep 17 00:00:00 2001 From: Rajendra Nayak Date: Wed, 8 Apr 2020 19:16:27 +0530 Subject: [PATCH] opp: Manage empty OPP tables with clk handle With OPP core now supporting DVFS for IO devices, we have instances of IO devices (same IP block) which require an OPP on some platforms/SoCs while just needing to scale the clock on some others. In order to avoid conditional code in every driver which supports such devices (to check for availability of OPPs and then deciding to do either dev_pm_opp_set_rate() or clk_set_rate()) add support to manage empty OPP tables with a clk handle. This makes dev_pm_opp_set_rate() equivalent of a clk_set_rate() for devices with just a clk and no OPPs specified, and makes dev_pm_opp_set_rate(0) bail out without throwing an error. Signed-off-by: Rajendra Nayak Signed-off-by: Viresh Kumar --- drivers/opp/core.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) 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)) {