[PATCH v3 1/1] i2c: qcom-cci: Fix ordering of pm_runtime_xx and i2c_add_adapter

From: Bryan O'Donoghue
Date: Mon Oct 17 2022 - 22:19:43 EST


When we compile-in the CCI along with the imx412 driver and run on the RB5
we see that i2c_add_adapter() causes the probe of the imx412 driver to
happen.

This probe tries to perform an i2c xfer() and the xfer() in i2c-qcom-cci.c
fails on pm_runtime_get() because the i2c-qcom-cci.c::probe() function has
not completed to pm_runtime_enable(dev).

Fix this sequence by ensuring pm_runtime_xxx() calls happen prior to adding
the i2c adapter.

Fixes: e517526195de ("i2c: Add Qualcomm CCI I2C driver")
Reported-by: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
Tested-by: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-qcom-cci.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-qcom-cci.c b/drivers/i2c/busses/i2c-qcom-cci.c
index 87739fb4388b..a4b97fe3c3a5 100644
--- a/drivers/i2c/busses/i2c-qcom-cci.c
+++ b/drivers/i2c/busses/i2c-qcom-cci.c
@@ -639,6 +639,11 @@ static int cci_probe(struct platform_device *pdev)
if (ret < 0)
goto error;

+ pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
for (i = 0; i < cci->data->num_masters; i++) {
if (!cci->master[i].cci)
continue;
@@ -650,14 +655,12 @@ static int cci_probe(struct platform_device *pdev)
}
}

- pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
- pm_runtime_use_autosuspend(dev);
- pm_runtime_set_active(dev);
- pm_runtime_enable(dev);
-
return 0;

error_i2c:
+ pm_runtime_disable(dev);
+ pm_runtime_dont_use_autosuspend(dev);
+
for (--i ; i >= 0; i--) {
if (cci->master[i].cci) {
i2c_del_adapter(&cci->master[i].adap);
--
2.34.1