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

18 Oct 2022

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@linaro.org
Reviewed-by: Vladimir Zapolskiy vladimir.zapolskiy@linaro.org
Tested-by: Vladimir Zapolskiy vladimir.zapolskiy@linaro.org
Cc: stable@vger.kernel.org
Signed-off-by: Bryan O'Donoghue bryan.odonoghue@linaro.org
---
 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


    