lkml.org 
[lkml]   [2018]   [May]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH 2/2] usb: dwc3: of_simple: don't call pm_runtime_set_active()
    From
    Date

    On 30/05/18 15:31, Felipe Balbi wrote:
    > Roger Quadros <rogerq@ti.com> writes:
    >
    >> Don't call pm_runtime_set_active() as it will prevent the device
    >> from being activated in the next pm_runtime_get_sync() call.
    >>
    >> Also call pm_runtime_get_sync() before of_platform_populate().
    >>
    >> Signed-off-by: Roger Quadros <rogerq@ti.com>
    >
    > This patch is wrong.
    >
    >> ---
    >> drivers/usb/dwc3/dwc3-of-simple.c | 7 +++----
    >> 1 file changed, 3 insertions(+), 4 deletions(-)
    >>
    >> diff --git a/drivers/usb/dwc3/dwc3-of-simple.c b/drivers/usb/dwc3/dwc3-of-simple.c
    >> index e98d221..2cbb5c0 100644
    >> --- a/drivers/usb/dwc3/dwc3-of-simple.c
    >> +++ b/drivers/usb/dwc3/dwc3-of-simple.c
    >> @@ -121,6 +121,9 @@ static int dwc3_of_simple_probe(struct platform_device *pdev)
    >> if (ret)
    >> goto err_resetc_assert;
    >>
    >> + pm_runtime_enable(dev);
    >> + pm_runtime_get_sync(dev);
    >
    > No, this is the wrong way to do things. My device should be enabled
    > already from probe, specially since I have already enabled clocks.

    As far as I understood just enabling clocks (which might not include bus clock)
    doesn't ensure device is enabled.

    Did you mean that I don't need to do a pm_runtime_get_sync() to enable my device in probe?
    Who is enabling by device for me then? Is device core supposed to do it?

    >
    >> ret = of_platform_populate(np, NULL, NULL, dev);
    >> if (ret) {
    >> for (i = 0; i < simple->num_clocks; i++) {
    >> @@ -131,10 +134,6 @@ static int dwc3_of_simple_probe(struct platform_device *pdev)
    >> goto err_resetc_assert;
    >> }
    >>
    >> - pm_runtime_set_active(dev);
    >> - pm_runtime_enable(dev);
    >> - pm_runtime_get_sync(dev);
    >
    > this hunk is not wrong at all.
    >

    The issue I was facing is that without this patch my device wasn't being enabled
    as pm_runtime_set_active() is being done _before_ pm_runtime_get_sync().
    It could be an issue with the platform's PM domain code as well.

    Tero/Dave what do you think?

    --
    cheers,
    -roger

    Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
    Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

    \
     
     \ /
      Last update: 2018-05-31 09:24    [W:3.132 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site