Tegra had always been switching to intermediate frequency (pll_p_clk) since
ever. CPUFreq core has better support for handling notifications for these
frequencies and so we can adapt Tegra's driver to it.

Tested-by: Stephen Warren <swar...@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
 drivers/cpufreq/tegra-cpufreq.c | 71 +++++++++++++++++++++--------------------
 1 file changed, 37 insertions(+), 34 deletions(-)

diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra-cpufreq.c
index 6e774c6..fc66442 100644
--- a/drivers/cpufreq/tegra-cpufreq.c
+++ b/drivers/cpufreq/tegra-cpufreq.c
@@ -46,10 +46,19 @@ static struct clk *pll_x_clk;
 static struct clk *pll_p_clk;
 static struct clk *emc_clk;
 
-static int tegra_cpu_clk_set_rate(unsigned long rate)
+static unsigned int
+tegra_get_intermediate(struct cpufreq_policy *policy, unsigned int index)
+{
+       return clk_get_rate(pll_p_clk) / 1000; /* kHz */
+}
+
+static int
+tegra_target_intermediate(struct cpufreq_policy *policy, unsigned int 
frequency)
 {
        int ret;
 
+       WARN_ON(frequency != clk_get_rate(pll_p_clk) / 1000);
+
        /*
         * Take an extra reference to the main pll so it doesn't turn
         * off when we move the cpu off of it
@@ -57,28 +66,9 @@ static int tegra_cpu_clk_set_rate(unsigned long rate)
        clk_prepare_enable(pll_x_clk);
 
        ret = clk_set_parent(cpu_clk, pll_p_clk);
-       if (ret) {
-               pr_err("Failed to switch cpu to clock pll_p\n");
-               goto out;
-       }
-
-       if (rate == clk_get_rate(pll_p_clk))
-               goto out;
-
-       ret = clk_set_rate(pll_x_clk, rate);
-       if (ret) {
-               pr_err("Failed to change pll_x to %lu\n", rate);
-               goto out;
-       }
-
-       ret = clk_set_parent(cpu_clk, pll_x_clk);
-       if (ret) {
-               pr_err("Failed to switch cpu to clock pll_x\n");
-               goto out;
-       }
+       if (ret)
+               clk_disable_unprepare(pll_x_clk);
 
-out:
-       clk_disable_unprepare(pll_x_clk);
        return ret;
 }
 
@@ -98,10 +88,21 @@ static int tegra_target(struct cpufreq_policy *policy, 
unsigned int index)
        else
                clk_set_rate(emc_clk, 100000000);  /* emc 50Mhz */
 
-       ret = tegra_cpu_clk_set_rate(rate * 1000);
+       if (rate == clk_get_rate(pll_p_clk))
+               goto out;
+
+       ret = clk_set_rate(pll_x_clk, rate * 1000);
+       if (ret) {
+               pr_err("Failed to change pll_x to %lu\n", rate);
+               goto out;
+       }
+
+       ret = clk_set_parent(cpu_clk, pll_x_clk);
        if (ret)
-               pr_err("cpu-tegra: Failed to set cpu frequency to %lu kHz\n",
-                       rate);
+               pr_err("Failed to switch cpu to clock pll_x\n");
+
+out:
+       clk_disable_unprepare(pll_x_clk);
 
        return ret;
 }
@@ -137,16 +138,18 @@ static int tegra_cpu_exit(struct cpufreq_policy *policy)
 }
 
 static struct cpufreq_driver tegra_cpufreq_driver = {
-       .flags          = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
-       .verify         = cpufreq_generic_frequency_table_verify,
-       .target_index   = tegra_target,
-       .get            = cpufreq_generic_get,
-       .init           = tegra_cpu_init,
-       .exit           = tegra_cpu_exit,
-       .name           = "tegra",
-       .attr           = cpufreq_generic_attr,
+       .flags                  = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
+       .verify                 = cpufreq_generic_frequency_table_verify,
+       .get_intermediate       = tegra_get_intermediate,
+       .target_intermediate    = tegra_target_intermediate,
+       .target_index           = tegra_target,
+       .get                    = cpufreq_generic_get,
+       .init                   = tegra_cpu_init,
+       .exit                   = tegra_cpu_exit,
+       .name                   = "tegra",
+       .attr                   = cpufreq_generic_attr,
 #ifdef CONFIG_PM
-       .suspend        = cpufreq_generic_suspend,
+       .suspend                = cpufreq_generic_suspend,
 #endif
 };
 
-- 
2.0.0.rc2

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