[PATCH net-next 3/6] net: ipa: re-enable transmit in PM WQ context
From: Alex Elder <hidden>
Date: 2021-08-12 19:50:46
Also in:
lkml
Subsystem:
networking drivers, qcom ipa driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Alex Elder, Linus Torvalds
Create a new work structure in the modem private data, and use it to re-enable the modem network device transmit queue when resuming. This is needed by the next patch, which stops the TX queue if IPA power isn't active when a transmit request arrives. Packets will start arriving the instant the TX queue is enabled, but resuming isn't complete until ipa_modem_resume() returns. This way we're sure to be resumed before transmits are allowed again. Cancel it before calling ipa_stop() in ipa_modem_stop() to ensure the transmit queue restart completes before it gets stopped there. Signed-off-by: Alex Elder <redacted> --- drivers/net/ipa/ipa_modem.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ipa/ipa_modem.c b/drivers/net/ipa/ipa_modem.c
index 06e44afd2cf66..0a3b034614b61 100644
--- a/drivers/net/ipa/ipa_modem.c
+++ b/drivers/net/ipa/ipa_modem.c@@ -9,6 +9,7 @@ #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/if_rmnet.h> +#include <linux/pm_runtime.h> #include <linux/remoteproc/qcom_rproc.h> #include "ipa.h"
@@ -33,9 +34,14 @@ enum ipa_modem_state { IPA_MODEM_STATE_STOPPING, }; -/** struct ipa_priv - IPA network device private data */ +/** + * struct ipa_priv - IPA network device private data + * @ipa: IPA pointer + * @work: Work structure used to wake the modem netdev TX queue + */ struct ipa_priv { struct ipa *ipa; + struct work_struct work; }; /** ipa_open() - Opens the modem network interface */
@@ -189,6 +195,21 @@ void ipa_modem_suspend(struct net_device *netdev) ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); } +/** + * ipa_modem_wake_queue_work() - enable modem netdev queue + * @work: Work structure + * + * Re-enable transmit on the modem network device. This is called + * in (power management) work queue context, scheduled when resuming + * the modem. + */ +static void ipa_modem_wake_queue_work(struct work_struct *work) +{ + struct ipa_priv *priv = container_of(work, struct ipa_priv, work); + + netif_wake_queue(priv->ipa->modem_netdev); +} + /** ipa_modem_resume() - resume callback for runtime_pm * @dev: pointer to device *
@@ -205,7 +226,8 @@ void ipa_modem_resume(struct net_device *netdev) ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); - netif_wake_queue(netdev); + /* Arrange for the TX queue to be restarted */ + (void)queue_pm_work(&priv->work); } int ipa_modem_start(struct ipa *ipa)
@@ -233,6 +255,7 @@ int ipa_modem_start(struct ipa *ipa) SET_NETDEV_DEV(netdev, &ipa->pdev->dev); priv = netdev_priv(netdev); priv->ipa = ipa; + INIT_WORK(&priv->work, ipa_modem_wake_queue_work); ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = netdev; ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = netdev; ipa->modem_netdev = netdev;
@@ -277,6 +300,9 @@ int ipa_modem_stop(struct ipa *ipa) /* Clean up the netdev and endpoints if it was started */ if (netdev) { + struct ipa_priv *priv = netdev_priv(netdev); + + cancel_work_sync(&priv->work); /* If it was opened, stop it first */ if (netdev->flags & IFF_UP) (void)ipa_stop(netdev);
--
2.27.0