[PATCH v6 2/6] spi: spi-geni-qcom: Use OPP API to set clk/perf state

Rajendra Nayak
2020-06-15T12:03:37Z

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 <rnayak@codeaurora.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Alok Chauhan <alokc@codeaurora.org>
Cc: Akash Asthana <akashast@codeaurora.org>
Cc: linux-spi@vger.kernel.org
---
This patch needs to land via the msm tree. Mark has acked v5, so
this is good to land I think. v6 is just rebased on 5.8-rc1.

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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