From 6bac9bc273cdab6157ad7a2ead09400aabfc445b Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 24 Apr 2019 18:16:32 +0200 Subject: [PATCH] i2c: designware: ratelimit 'transfer when suspended' errors There are two problems with dev_err() here. One: It is not ratelimited. Two: We don't see which driver tried to transfer something with a suspended adapter. Switch to dev_WARN_ONCE to fix both issues. Drawback is that we don't see if multiple drivers are trying to transfer while suspended. They need to be discovered one after the other now. This is better than a high CPU load because a really broken driver might try to resend endlessly. Link: https://bugs.archlinux.org/task/62391 Fixes: 275154155538 ("i2c: designware: Do not allow i2c_dw_xfer() calls while suspended") Signed-off-by: Wolfram Sang Reported-by: skidnik Acked-by: Jarkko Nikula Reviewed-by: Andy Shevchenko Tested-by: skidnik Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-designware-master.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index bb8e3f1..d464799 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -426,8 +426,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) pm_runtime_get_sync(dev->dev); - if (dev->suspended) { - dev_err(dev->dev, "Error %s call while suspended\n", __func__); + if (dev_WARN_ONCE(dev->dev, dev->suspended, "Transfer while suspended\n")) { ret = -ESHUTDOWN; goto done_nolock; } -- 2.7.4