Re: [PATCH 2/4] i2c: designware-platdrv: fix unbalanced clk enable and prepare

From: Jarkko Nikula
Date: Wed Apr 20 2016 - 08:55:45 EST


On 04/14/2016 03:53 PM, Jisheng Zhang wrote:
If i2c_dw_probe() fail, we should call i2c_dw_plat_prepare_clk() to
disable and unprepare the clk, otherwise the clk enable and prepare
is left unbalanced.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
drivers/i2c/busses/i2c-designware-platdrv.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 00f9e99..1488cea 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -268,6 +268,8 @@ rpm_disable:
pm_runtime_put_noidle(&pdev->dev);
}

+ i2c_dw_plat_prepare_clk(dev, false);
+
return r;
}

This is a bit unclear to me does devm_clk_get take care of clk disabling in case of probe error or driver removal?

I see Andy's 1cb715ca4694 ("i2c-designware: move to managed functions (devm_*)") removed it but at quick look drivers/clk/clk-devres.c: devm_clk_release() calls only clk_put and I don't see disable is done down the path.

--
Jarkko