Hi Loic,
On 2/3/22 7:29 PM, Loic Poulain wrote:
Hi Vladimir,
On Thu, 3 Feb 2022 at 17:47, Vladimir Zapolskiy
<vladimir.zapolskiy@xxxxxxxxxx> wrote:
The change is wanted to postpone initialization of busses on CCI controller
by cci_init() and cci_reset() till adapters are registered, the later is
needed for adding I2C bus devices and get correspondent vbus regulators.
This is odd, I don't think it's a good idea to register an adapter
which is not yet initialized. Could you elaborate on why you need to
do this, if you can't access the controller without this regulator
enabled, maybe it is more than vbus supply, and, in that case, it
should be enabled from your probe function.
thank you for review, the controller can be accessed without a vbus regulator,
but I2C devices connected to the master controller can not.
The registration of a master controller device done by i2c_add_adapter()
should be safe to defer IMO, because there shall be no communication on
the bus at this point, there are no slaves before probe completion, thus
cci_init()/cci_reset() can be safely called afterwards.
The rationale of the change is to merge two loops over busses, see change 6/9,
keeping two loops extremely complicates the proper resource management.
--
Best wishes,
Vladimir
Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-qcom-cci.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/drivers/i2c/busses/i2c-qcom-cci.c b/drivers/i2c/busses/i2c-qcom-cci.c
index cf54f1cb4c57..eebf9603d3d1 100644
--- a/drivers/i2c/busses/i2c-qcom-cci.c
+++ b/drivers/i2c/busses/i2c-qcom-cci.c
@@ -630,14 +630,6 @@ static int cci_probe(struct platform_device *pdev)
val = readl(cci->base + CCI_HW_VERSION);
dev_dbg(dev, "CCI HW version = 0x%08x", val);
- ret = cci_reset(cci);
- if (ret < 0)
- goto error;
-
- ret = cci_init(cci);
- if (ret < 0)
- goto error;
-
for (i = 0; i < cci->data->num_masters; i++) {
if (!cci->master[i].cci)
continue;
@@ -649,6 +641,14 @@ static int cci_probe(struct platform_device *pdev)
}
}
+ ret = cci_reset(cci);
+ if (ret < 0)
+ goto error_i2c;
+
+ ret = cci_init(cci);
+ if (ret < 0)
+ goto error_i2c;
+
pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC);
pm_runtime_use_autosuspend(dev);
pm_runtime_set_active(dev);
@@ -663,7 +663,6 @@ static int cci_probe(struct platform_device *pdev)
of_node_put(cci->master[i].adap.dev.of_node);
}
}
-error:
disable_irq(cci->irq);
disable_clocks:
cci_disable_clocks(cci);
--
2.33.0
