Hi,
On Fri, Nov 2, 2018 at 11:35 AM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
>
> We need to enable runtime PM on this i2c controller before populating
> child devices with i2c_add_adapter(). Otherwise, if a child device uses
> runtime PM and stays runtime PM enabled we'll get the following warning
> at boot.
>
> Enabling runtime PM for inactive device (a98000.i2c) with active children
> WARNING: CPU: 4 PID: 1 at drivers/base/power/runtime.c:1300 pm_runtime_enable+0xd8/0xf8
> Modules linked in:
> CPU: 4 PID: 1 Comm: swapper/0 Not tainted 4.19.0 #6
> elants_i2c 14-0010: 14-0010 supply vccio not found, using dummy regulator
> pstate: 60c00089 (nZCv daIf +PAN +UAO)
> pc : pm_runtime_enable+0xd8/0xf8
> lr : pm_runtime_enable+0xd8/0xf8
> sp : ffffffc0de257a30
> x29: ffffffc0de257a30 x28: 0000000000061a80
> x27: ffffff9008ea7118
> x26: ffffffc0d718b058
> x25: ffffff9008ea7000 x24: ffffffc0d718a8dc
> x23: ffffffc0d718a8b0 x22: ffffffc0d823dd58
> x21: 0000000000000000 x20: ffffffc0d823dbc8
> x19: ffffffc0d823da90 x18: 000000007f743d9a
> x17: 0000000000000080 x16: 0000000000000003
> x15: 000000000000003f x14: 0720072007200720
> x13: 0720072007200720 x12: 0720072007200720
> x11: 0720072007200720 x10: 0720072007200720
> x9 : 0720072007200720 x8 : 0720072007200720
> x7 : ffffff900816da30 x6 : 0000000000000000
> x5 : 0000000000000080 x4 : 0000000000000003
> x3 : ffffff900816f304 x2 : ffffffc0de248050
> x1 : 25045a74f48a7400 x0 : 25045a74f48a7400
> Call trace:
> pm_runtime_enable+0xd8/0xf8
> geni_i2c_probe+0x440/0x460
> platform_drv_probe+0x74/0xc8
> really_probe+0x1ac/0x35c
> driver_probe_device+0xd4/0x118
> __driver_attach+0xc8/0x118
> bus_for_each_dev+0xac/0xe8
> driver_attach+0x38/0x44
> bus_add_driver+0x15c/0x294
> driver_register+0x13c/0x198
> __platform_driver_register+0x88/0x94
> geni_i2c_driver_init+0x20/0x28
> do_one_initcall+0x250/0x4ec
> kernel_init_freeable+0x6f0/0x7c4
> kernel_init+0x18/0x120
> ret_from_fork+0x10/0x18
>
> Let's move the runtime PM enabling and setup to before we add the
> adapter, so that this device can respond to runtime PM requests from
> children.
>
> Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Cc: Alok Chauhan <alokc@xxxxxxxxxxxxxx>
> Fixes: 37692de5d523 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller")
> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-qcom-geni.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c
> index 527f55c8c4c7..145eb98ac8b4 100644
> --- a/drivers/i2c/busses/i2c-qcom-geni.c
> +++ b/drivers/i2c/busses/i2c-qcom-geni.c
> @@ -571,18 +571,19 @@ static int geni_i2c_probe(struct platform_device *pdev)
>
> dev_dbg(&pdev->dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
>
> - ret = i2c_add_adapter(&gi2c->adap);
> - if (ret) {
> - dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
> - return ret;
> - }
> -
> gi2c->suspended = 1;
> pm_runtime_set_suspended(gi2c->se.dev);
> pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
> pm_runtime_use_autosuspend(gi2c->se.dev);
> pm_runtime_enable(gi2c->se.dev);
>
> + ret = i2c_add_adapter(&gi2c->adap);
> + if (ret) {
> + dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
> + pm_runtime_disable(gi2c->se.dev);
> + return ret;
> + }
> +
Thanks for the fix. It looks good, but can you also swap the
pm_runtime_disable() and i2c_del_adapter() calls in geni_i2c_remove()
to match?
-Doug
