From fbadcde1572f6b00e1e343d8b24ec8bf7f3ec08d Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Tue, 30 Apr 2024 20:38:57 -0700 Subject: soc: qcom: pmic_glink: Make client-lock non-sleeping [ Upstream commit 9329933699b32d467a99befa20415c4b2172389a ] The recently introduced commit '635ce0db8956 ("soc: qcom: pmic_glink: don't traverse clients list without a lock")' ensured that the clients list is not modified while traversed. But the callback is made from the GLINK IRQ handler and as such this mutual exclusion can not be provided by a (sleepable) mutex. Replace the mutex with a spinlock. Fixes: 635ce0db8956 ("soc: qcom: pmic_glink: don't traverse clients list without a lock") Signed-off-by: Bjorn Andersson Reviewed-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20240430-pmic-glink-sleep-while-atomic-v1-1-88fb493e8545@quicinc.com Signed-off-by: Bjorn Andersson Signed-off-by: Sasha Levin --- drivers/soc/qcom/pmic_glink.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/soc/qcom/pmic_glink.c b/drivers/soc/qcom/pmic_glink.c index 062ff7b12de6..61a359938b6c 100644 --- a/drivers/soc/qcom/pmic_glink.c +++ b/drivers/soc/qcom/pmic_glink.c @@ -11,6 +11,7 @@ #include #include #include +#include enum { PMIC_GLINK_CLIENT_BATT = 0, @@ -39,7 +40,7 @@ struct pmic_glink { unsigned int pdr_state; /* serializing clients list updates */ - struct mutex client_lock; + spinlock_t client_lock; struct list_head clients; }; @@ -61,10 +62,11 @@ static void _devm_pmic_glink_release_client(struct device *dev, void *res) { struct pmic_glink_client *client = (struct pmic_glink_client *)res; struct pmic_glink *pg = client->pg; + unsigned long flags; - mutex_lock(&pg->client_lock); + spin_lock_irqsave(&pg->client_lock, flags); list_del(&client->node); - mutex_unlock(&pg->client_lock); + spin_unlock_irqrestore(&pg->client_lock, flags); } struct pmic_glink_client *devm_pmic_glink_register_client(struct device *dev, @@ -75,6 +77,7 @@ struct pmic_glink_client *devm_pmic_glink_register_client(struct device *dev, { struct pmic_glink_client *client; struct pmic_glink *pg = dev_get_drvdata(dev->parent); + unsigned long flags; client = devres_alloc(_devm_pmic_glink_release_client, sizeof(*client), GFP_KERNEL); if (!client) @@ -87,12 +90,12 @@ struct pmic_glink_client *devm_pmic_glink_register_client(struct device *dev, client->priv = priv; mutex_lock(&pg->state_lock); - mutex_lock(&pg->client_lock); + spin_lock_irqsave(&pg->client_lock, flags); list_add(&client->node, &pg->clients); client->pdr_notify(client->priv, pg->client_state); - mutex_unlock(&pg->client_lock); + spin_unlock_irqrestore(&pg->client_lock, flags); mutex_unlock(&pg->state_lock); devres_add(dev, client); @@ -115,6 +118,7 @@ static int pmic_glink_rpmsg_callback(struct rpmsg_device *rpdev, void *data, struct pmic_glink_client *client; struct pmic_glink_hdr *hdr; struct pmic_glink *pg = dev_get_drvdata(&rpdev->dev); + unsigned long flags; if (len < sizeof(*hdr)) { dev_warn(pg->dev, "ignoring truncated message\n"); @@ -123,12 +127,12 @@ static int pmic_glink_rpmsg_callback(struct rpmsg_device *rpdev, void *data, hdr = data; - mutex_lock(&pg->client_lock); + spin_lock_irqsave(&pg->client_lock, flags); list_for_each_entry(client, &pg->clients, node) { if (client->id == le32_to_cpu(hdr->owner)) client->cb(data, len, client->priv); } - mutex_unlock(&pg->client_lock); + spin_unlock_irqrestore(&pg->client_lock, flags); return 0; } @@ -168,6 +172,7 @@ static void pmic_glink_state_notify_clients(struct pmic_glink *pg) { struct pmic_glink_client *client; unsigned int new_state = pg->client_state; + unsigned long flags; if (pg->client_state != SERVREG_SERVICE_STATE_UP) { if (pg->pdr_state == SERVREG_SERVICE_STATE_UP && pg->ept) @@ -178,10 +183,10 @@ static void pmic_glink_state_notify_clients(struct pmic_glink *pg) } if (new_state != pg->client_state) { - mutex_lock(&pg->client_lock); + spin_lock_irqsave(&pg->client_lock, flags); list_for_each_entry(client, &pg->clients, node) client->pdr_notify(client->priv, new_state); - mutex_unlock(&pg->client_lock); + spin_unlock_irqrestore(&pg->client_lock, flags); pg->client_state = new_state; } } @@ -268,7 +273,7 @@ static int pmic_glink_probe(struct platform_device *pdev) pg->dev = &pdev->dev; INIT_LIST_HEAD(&pg->clients); - mutex_init(&pg->client_lock); + spin_lock_init(&pg->client_lock); mutex_init(&pg->state_lock); match_data = (unsigned long *)of_device_get_match_data(&pdev->dev); -- cgit v1.2.3