Re: [PATCH next] i2c: qcom-cci: Fix error checking in cci_probe()

From: Bryan O'Donoghue
Date: Thu Aug 24 2023 - 05:11:02 EST


On 23/08/2023 20:42, Harshit Mogalapalli wrote:
devm_clk_bulk_get_all() can return zero when no clocks are obtained.
Passing zero to dev_err_probe() is a success which is incorrect.

Fixes: 605efbf43813 ("i2c: qcom-cci: Use dev_err_probe in probe function")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx>
---
Only compile tested, found by static analysis with smatch.

https://lore.kernel.org/all/CAA8EJprTOjbOy7N5+8NiJaNNhK+_btdUUFcpHKPkMuCZj5umMA@xxxxxxxxxxxxxx/
^^ I reported initially here, Dmitry suggested we need to fix it in a
different patch.

the Fixes commit used above pointed this bug, but the real fixes tag is this:
Fixes: e517526195de ("i2c: Add Qualcomm CCI I2C driver")
---
drivers/i2c/busses/i2c-qcom-cci.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-qcom-cci.c b/drivers/i2c/busses/i2c-qcom-cci.c
index cf13abec05f1..414882c57d7f 100644
--- a/drivers/i2c/busses/i2c-qcom-cci.c
+++ b/drivers/i2c/busses/i2c-qcom-cci.c
@@ -588,8 +588,10 @@ static int cci_probe(struct platform_device *pdev)
/* Clocks */
ret = devm_clk_bulk_get_all(dev, &cci->clocks);
- if (ret < 1)
+ if (ret < 0)
return dev_err_probe(dev, ret, "failed to get clocks\n");
+ else if (!ret)
+ return dev_err_probe(dev, -EINVAL, "not enough clocks in DT\n");
cci->nclocks = ret;
/* Retrieve CCI clock rate */
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>