On Tue, Dec 12, 2017 at 03:58:54PM -0800, Bjorn Andersson wrote: > Rather than selectively creating devices only for the channels that the > remote have moved to "opening" state let's create devices for all > channels found. The driver model will match drivers to the ones we care > about and attempt to open these. > > The one case where this fails is if the user loads a firmware that lacks > a particular channel of the previous firmware that was running, in which > case we would find the old channel and attempt to probe it. The channel > opening handshake will ensure this will result in a graceful failure. Another case is that on the 8992/8994 there is no call to create_device due to the RPM always leaving the RX channel in the CLOSING state. I believe this may be happening in the LK based on this message: "[270] Waiting for the RPM to populate smd channel table " The exact same behaviour has been observed on the downstream kernel (initial state needing to be ignored in order). Stated another way, downstream _BLINDLY_ calls platform_device_register in smd_alloc_channel regardless of the value returned by ch->half_ch->get_state(ch->recv)); In the afore mentioned case _ALL_ of the images (RPM, bootloader: BZ11h, LK) used on the Nexus 5X/6P under test were unmodified as provided by MSM and/or Google. > > The result of this patch is that we will actively open the RPM channel > even though it's left in a state other than "opening" after the boot > loader's closing of the channel. > Its been a while since I looked at this closely but, isn't the result of this patch that we now will create a channel / register a platform device if the state of the channel is left in any state. > Reported-by: Jeremy McNicoll <jmcnicol@xxxxxxxxxx> .....and Suggested-by: Jeremy McNicoll <jeremymc@xxxxxxxxxx> > Reported-by: Will Newton <will.newton@xxxxxxxxx> > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > --- > drivers/rpmsg/qcom_smd.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c > index 58dd44493420..1beddea6f087 100644 > --- a/drivers/rpmsg/qcom_smd.c > +++ b/drivers/rpmsg/qcom_smd.c > @@ -1225,11 +1225,6 @@ static void qcom_channel_state_worker(struct work_struct *work) > if (channel->state != SMD_CHANNEL_CLOSED) > continue; > > - remote_state = GET_RX_CHANNEL_INFO(channel, state); > - if (remote_state != SMD_CHANNEL_OPENING && > - remote_state != SMD_CHANNEL_OPENED) > - continue; > - The code looks good, and the change is _VERY_ familiar. -jeremy > if (channel->registered) > continue; > > -- > 2.15.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
