bus: mhi: host: pci_generic: Disable runtime PM for QDU100

The QDU100 device does not support the MHI M3 state, necessitating the
disabling of runtime PM for this device. It is essential to disable
runtime PM if the device does not support M3 state.

Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
[mani: Fixed the kdoc comment for no_m3]
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
Link: https://patch.msgid.link/20250425-vdev_next-20250411_pm_disable-v4-1-d4870a73ebf9@quicinc.com

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
index 92bd133e7c456ee64d79dfb62f3349f268a4af2c..5c01c23d0bcfedd23f975e99845d5fa88940ccde 100644 (file)
--- a/drivers/bus/mhi/host/pci_generic.c
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -43,6 +43,7 @@
  * @mru_default: default MRU size for MBIM network packets
  * @sideband_wake: Devices using dedicated sideband GPIO for wakeup instead
  *                of inband wake support (such as sdx24)
+ * @no_m3: M3 not supported
  */
 struct mhi_pci_dev_info {
        const struct mhi_controller_config *config;
@@ -54,6 +55,7 @@ struct mhi_pci_dev_info {
        unsigned int dma_data_width;
        unsigned int mru_default;
        bool sideband_wake;
+       bool no_m3;
 };
 
 #define MHI_CHANNEL_CONFIG_UL(ch_num, ch_name, el_count, ev_ring) \
@@ -295,6 +297,7 @@ static const struct mhi_pci_dev_info mhi_qcom_qdu100_info = {
        .bar_num = MHI_PCI_DEFAULT_BAR_NUM,
        .dma_data_width = 32,
        .sideband_wake = false,
+       .no_m3 = true,
 };
 
 static const struct mhi_channel_config mhi_qcom_sa8775p_channels[] = {
@@ -1306,8 +1309,8 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
        /* start health check */
        mod_timer(&mhi_pdev->health_check_timer, jiffies + HEALTH_CHECK_PERIOD);
 
-       /* Only allow runtime-suspend if PME capable (for wakeup) */
-       if (pci_pme_capable(pdev, PCI_D3hot)) {
+       /* Allow runtime suspend only if both PME from D3Hot and M3 are supported */
+       if (pci_pme_capable(pdev, PCI_D3hot) && !(info->no_m3)) {
                pm_runtime_set_autosuspend_delay(&pdev->dev, 2000);
                pm_runtime_use_autosuspend(&pdev->dev);
                pm_runtime_mark_last_busy(&pdev->dev);