[PATCH v5 2/6] spi: spi-geni-qcom: Use OPP API to set clk/perf state

[Rajendra Nayak]

geni spi needs to express a perforamnce state requirement on CX
depending on the frequency of the clock rates. Use OPP table from
DT to register with OPP framework and use dev_pm_opp_set_rate() to
set the clk/perf state.

Signed-off-by: Rajendra Nayak <rna...@codeaurora.org>
Reviewed-by: Matthias Kaehlcke <m...@chromium.org>
Cc: Mark Brown <broo...@kernel.org>
Cc: Alok Chauhan <al...@codeaurora.org>
Cc: Akash Asthana <akash...@codeaurora.org>
Cc: linux-...@vger.kernel.org
---
This patch will need to land via the msm tree because of a dependency
with another change.
Change in v5: OPP cleanup done as the last thing in spi_geni_remove()

 drivers/spi/spi-geni-qcom.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index c397242..0d7ead1 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -7,6 +7,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pm_opp.h>
 #include <linux/pm_runtime.h>
 #include <linux/qcom-geni-se.h>
 #include <linux/spi/spi.h>
@@ -95,7 +96,6 @@ static int get_spi_clk_cfg(unsigned int speed_hz,
 {
        unsigned long sclk_freq;
        unsigned int actual_hz;
-       struct geni_se *se = &mas->se;
        int ret;
 
        ret = geni_se_clk_freq_match(&mas->se,
@@ -112,9 +112,9 @@ static int get_spi_clk_cfg(unsigned int speed_hz,
 
        dev_dbg(mas->dev, "req %u=>%u sclk %lu, idx %d, div %d\n", speed_hz,
                                actual_hz, sclk_freq, *clk_idx, *clk_div);
-       ret = clk_set_rate(se->clk, sclk_freq);
+       ret = dev_pm_opp_set_rate(mas->dev, sclk_freq);
        if (ret)
-               dev_err(mas->dev, "clk_set_rate failed %d\n", ret);
+               dev_err(mas->dev, "dev_pm_opp_set_rate failed %d\n", ret);
        return ret;
 }
 
@@ -561,6 +561,17 @@ static int spi_geni_probe(struct platform_device *pdev)
        mas->se.wrapper = dev_get_drvdata(dev->parent);
        mas->se.base = base;
        mas->se.clk = clk;
+       mas->se.opp_table = dev_pm_opp_set_clkname(&pdev->dev, "se");
+       if (IS_ERR(mas->se.opp_table))
+               return PTR_ERR(mas->se.opp_table);
+       /* OPP table is optional */
+       ret = dev_pm_opp_of_add_table(&pdev->dev);
+       if (!ret) {
+               mas->se.has_opp_table = true;
+       } else if (ret != -ENODEV) {
+               dev_err(&pdev->dev, "invalid OPP table in device tree\n");
+               return ret;
+       }
 
        spi->bus_num = -1;
        spi->dev.of_node = dev->of_node;
@@ -596,6 +607,9 @@ static int spi_geni_probe(struct platform_device *pdev)
 spi_geni_probe_runtime_disable:
        pm_runtime_disable(dev);
        spi_master_put(spi);
+       if (mas->se.has_opp_table)
+               dev_pm_opp_of_remove_table(&pdev->dev);
+       dev_pm_opp_put_clkname(mas->se.opp_table);
        return ret;
 }
 
@@ -609,6 +623,9 @@ static int spi_geni_remove(struct platform_device *pdev)
 
        free_irq(mas->irq, spi);
        pm_runtime_disable(&pdev->dev);
+       if (mas->se.has_opp_table)
+               dev_pm_opp_of_remove_table(&pdev->dev);
+       dev_pm_opp_put_clkname(mas->se.opp_table);
        return 0;
 }
 
@@ -617,6 +634,9 @@ static int __maybe_unused spi_geni_runtime_suspend(struct 
device *dev)
        struct spi_master *spi = dev_get_drvdata(dev);
        struct spi_geni_master *mas = spi_master_get_devdata(spi);
 
+       /* Drop the performance state vote */
+       dev_pm_opp_set_rate(dev, 0);
+
        return geni_se_resources_off(&mas->se);
 }
 
-- 
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