This is a note to let you know that I've just added the patch titled
i2c: i2c-cadence: Initialize configuration before probing devices
to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: i2c-i2c-cadence-initialize-configuration-before-probing-devices.patch and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Wed Dec 6 17:39:55 CET 2017
From: Mike Looijmans mike.looijmans@topic.nl Date: Mon, 16 Jan 2017 15:49:38 +0100 Subject: i2c: i2c-cadence: Initialize configuration before probing devices
From: Mike Looijmans mike.looijmans@topic.nl
[ Upstream commit 0e1929dedea36781e25902118c93edd8d8f09af1 ]
The cadence I2C driver calls cdns_i2c_writereg(..) to setup a workaround in the controller, but did so after calling i2c_add_adapter() which starts probing devices on the bus. Change the order so that the configuration is completely finished before using the adapter.
Signed-off-by: Mike Looijmans mike.looijmans@topic.nl Signed-off-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/busses/i2c-cadence.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/i2c/busses/i2c-cadence.c +++ b/drivers/i2c/busses/i2c-cadence.c @@ -962,10 +962,6 @@ static int cdns_i2c_probe(struct platfor goto err_clk_dis; }
- ret = i2c_add_adapter(&id->adap); - if (ret < 0) - goto err_clk_dis; - /* * Cadence I2C controller has a bug wherein it generates * invalid read transaction after HW timeout in master receiver mode. @@ -975,6 +971,10 @@ static int cdns_i2c_probe(struct platfor */ cdns_i2c_writereg(CDNS_I2C_TIMEOUT_MAX, CDNS_I2C_TIME_OUT_OFFSET);
+ ret = i2c_add_adapter(&id->adap); + if (ret < 0) + goto err_clk_dis; + dev_info(&pdev->dev, "%u kHz mmio %08lx irq %d\n", id->i2c_clk / 1000, (unsigned long)r_mem->start, id->irq);
Patches currently in stable-queue which might be from mike.looijmans@topic.nl are
queue-4.9/i2c-i2c-cadence-initialize-configuration-before-probing-devices.patch