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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: ljajNVqJrapY-BdUhc6prJ_aTUMpcbKM X-Authority-Analysis: v=2.4 cv=fNusTpae c=1 sm=1 tr=0 ts=6ad09e82 cx=c_pps a=mPf7EqFMSY9/WdsSgAYMbA==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=660iZSQnnn4A:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=3WHJM1ZQz_JShphwDgj5:22 a=zRDqW-Egxz1XbUpwT2YA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=dawVfQjAaf238kedN5IG:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYxMDE1MDAzOCBTYWx0ZWRfX7USt8fJsk9+2 fkOTsosxcmBzaYpI+W0Rsu3w9ibx4THcvdGmJMfWQopAhf7VK0KA2PtksWyEVCRV4OpQdmZsHUK 8ihIOrqTOWhX+aCsp9C0JuisdfLoA/iUtMXRKhmzlBm3/MLM+IAP9DgrohkWz5Y5EY/+c96Y6DH vdgm1s3I6MJPZaqC3rw8izESs1YPo+S7C4N95lOhpyt+CjdiVtj78TIb2zEEV9ntgFZHkVcWRTh vyNw175TrqDtLg/4sn1r6fPz+H4V04euaZ/IZ5wzbg3YCciL5XzhwuPZyHbj2PlZm4BTG65C1rD 7n7ZPBVs63sN6Fz7iL+ZlbwEwKa6XA9S8dBugyQsY0ZI1QdbMfYX6gD2vEXIO5HeI3wIagsV8OO nY+8ZuEkXk4EJC4yBT1G8vk9Hqd/T/MtI3uK/KVzOmn4fh5/jbww1d/QZIGOhWqAnfH3MNOtg9M P0H8JSlaT0doAVwuhJA== X-Proofpoint-Spam-Info: AW1haW4tMjYxMDE1MDAzOCBTYWx0ZWRfX9qtZ7Ahr9TJK pP6qUHddXjW/bqB9kWqjdinR1vCSmOYwH3OU3/t7PyzsiIhGqsL/MpPpOCi7f7zhWTxi2bNn2/G MOtsusOvBasI3DxvBYrHTk2Ymofds4g= X-Proofpoint-GUID: ljajNVqJrapY-BdUhc6prJ_aTUMpcbKM X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-10-13_01,2026-10-14_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 phishscore=0 bulkscore=0 lowpriorityscore=0 impostorscore=0 spamscore=0 clxscore=1015 priorityscore=1501 adultscore=0 malwarescore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2610080000 definitions=main-2610150038 On 9/18/26 3:28 PM, Praveen Talari wrote: > Hi David, > > On 18-09-2026 03:44, David Heidelberg via B4 Relay wrote: >> From: David Heidelberg [...] > Specifically, is pm_runtime_force_resume() leaving the device in a > runtime-suspended state despite restoring it from system suspend, or > is there some interaction with the console's runtime PM reference count > that prevents the port from being resumed before uart_resume_port() accesses > the registers? > > A bit more detail on why pm_runtime_force_resume() alone is insufficient > > would help understand the root cause. GPT came up with the following explanation: 1. qcom_geni_console_setup() takes a runtime-PM reference with pm_runtime_resume_and_get(). If the console is registered but no TTY is open, that leaves the port with a usage count of 1. 2. With console_suspend_enabled, qcom_geni_serial_suspend() calls pm_runtime_force_suspend() after serial-core suspends the port. 3. pm_runtime_force_suspend() considers a device with usage count <= 1 and no children eligible to remain suspended after system resume. It sets the runtime status to suspended without setting needs_force_resume. 4. Accordingly, pm_runtime_force_resume() skips the runtime-resume callback. It re-enables runtime PM, but does not power the GENI port back up. 5. uart_resume_port() restores console termios before its conditional TTY startup. If the TTY was never opened, that startup—and its runtime-PM get—doesn't happen. The console remains powered down. If a TTY was open, startup eventually wakes it, but only after the earlier register accesses. Konrad