[PATCH v3 04/11] i2c: riic: Enable runtime PM autosuspend support

From: Claudiu
Date: Thu Jul 11 2024 - 07:53:40 EST


From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>

Enable runtime PM autosuspend support for the RIIC driver. With this, in
case there are consecutive xfer requests the device wouldn't be runtime
enabled/disabled after each consecutive xfer but after the
the delay configured by user. With this, we can avoid touching hardware
registers involved in runtime PM suspend/resume saving in this way some
cycles. The default chosen autosuspend delay is zero to keep the
previous driver behavior.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---

Changes in v3:
- none

Changes in v2:
- none

drivers/i2c/busses/i2c-riic.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c
index 068f90ecf27e..46765715d39f 100644
--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -171,7 +171,8 @@ static int riic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
}

out:
- pm_runtime_put(dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);

return riic->err ?: num;
}
@@ -399,7 +400,8 @@ static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t)

riic_clear_set_bit(riic, ICCR1_IICRST, 0, RIIC_ICCR1);

- pm_runtime_put(dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
return 0;
}

@@ -479,6 +481,8 @@ static int riic_i2c_probe(struct platform_device *pdev)

i2c_parse_fw_timings(dev, &i2c_t, true);

+ pm_runtime_set_autosuspend_delay(dev, 0);
+ pm_runtime_use_autosuspend(dev);
pm_runtime_enable(dev);

ret = riic_init_hw(riic, &i2c_t);
@@ -496,6 +500,7 @@ static int riic_i2c_probe(struct platform_device *pdev)

out:
pm_runtime_disable(dev);
+ pm_runtime_dont_use_autosuspend(dev);
return ret;
}

@@ -512,6 +517,7 @@ static void riic_i2c_remove(struct platform_device *pdev)
}
i2c_del_adapter(&riic->adapter);
pm_runtime_disable(dev);
+ pm_runtime_dont_use_autosuspend(dev);
}

static const struct riic_of_data riic_rz_a_info = {
--
2.39.2