From: Xu Yang xu.yang_2@nxp.com
commit 451b15ed138ec15bffbebb58a00ebdd884c3e659 upstream.
The user may call role_store() when driver is handling ci_handle_id_switch() which is triggerred by otg event or power lost event. Unfortunately, the controller may go into chaos in this case. Fix this by protecting it with mutex lock.
Fixes: a932a8041ff9 ("usb: chipidea: core: add sysfs group") cc: stable@vger.kernel.org Acked-by: Peter Chen peter.chen@kernel.org Signed-off-by: Xu Yang xu.yang_2@nxp.com Link: https://lore.kernel.org/r/20230317061516.2451728-2-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/chipidea/ci.h | 2 ++ drivers/usb/chipidea/core.c | 8 +++++++- drivers/usb/chipidea/otg.c | 5 ++++- 3 files changed, 13 insertions(+), 2 deletions(-)
--- a/drivers/usb/chipidea/ci.h +++ b/drivers/usb/chipidea/ci.h @@ -204,6 +204,7 @@ struct hw_bank { * @in_lpm: if the core in low power mode * @wakeup_int: if wakeup interrupt occur * @rev: The revision number for controller + * @mutex: protect code from concorrent running when doing role switch */ struct ci_hdrc { struct device *dev; @@ -257,6 +258,7 @@ struct ci_hdrc { bool in_lpm; bool wakeup_int; enum ci_revision rev; + struct mutex mutex; };
static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci) --- a/drivers/usb/chipidea/core.c +++ b/drivers/usb/chipidea/core.c @@ -969,8 +969,12 @@ static ssize_t role_store(struct device if (role == CI_ROLE_END) return -EINVAL;
- if (role == ci->role) + mutex_lock(&ci->mutex); + + if (role == ci->role) { + mutex_unlock(&ci->mutex); return n; + }
pm_runtime_get_sync(dev); disable_irq(ci->irq); @@ -980,6 +984,7 @@ static ssize_t role_store(struct device ci_handle_vbus_change(ci); enable_irq(ci->irq); pm_runtime_put_sync(dev); + mutex_unlock(&ci->mutex);
return (ret == 0) ? n : ret; } @@ -1015,6 +1020,7 @@ static int ci_hdrc_probe(struct platform return -ENOMEM;
spin_lock_init(&ci->lock); + mutex_init(&ci->mutex); ci->dev = dev; ci->platdata = dev_get_platdata(dev); ci->imx28_write_fix = !!(ci->platdata->flags & --- a/drivers/usb/chipidea/otg.c +++ b/drivers/usb/chipidea/otg.c @@ -166,8 +166,10 @@ static int hw_wait_vbus_lower_bsv(struct
static void ci_handle_id_switch(struct ci_hdrc *ci) { - enum ci_role role = ci_otg_role(ci); + enum ci_role role;
+ mutex_lock(&ci->mutex); + role = ci_otg_role(ci); if (role != ci->role) { dev_dbg(ci->dev, "switching from %s to %s\n", ci_role(ci)->name, ci->roles[role]->name); @@ -197,6 +199,7 @@ static void ci_handle_id_switch(struct c if (role == CI_ROLE_GADGET) ci_handle_vbus_change(ci); } + mutex_unlock(&ci->mutex); } /** * ci_otg_work - perform otg (vbus/id) event handle