Messages in this thread | | | Date | Fri, 7 Jul 2023 08:50:38 -0700 | Subject | Re: [PATCH v2] i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue | From | Ray Jui <> |
| |
On 7/7/2023 1:49 AM, Chengfeng Ye wrote: > iproc_i2c_rd_reg() and iproc_i2c_wr_reg() are called from both > interrupt context (e.g. bcm_iproc_i2c_isr) and process context > (e.g. bcm_iproc_i2c_suspend). Therefore, interrupts should be > disabled to avoid potential deadlock. To prevent this scenario, > use spin_lock_irqsave(). > > Fixes: 9a1038728037 ("i2c: iproc: add NIC I2C support") > Signed-off-by: Chengfeng Ye <dg573847474@gmail.com> > --- > drivers/i2c/busses/i2c-bcm-iproc.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c > index 85d8a6b04885..30a2a3200bed 100644 > --- a/drivers/i2c/busses/i2c-bcm-iproc.c > +++ b/drivers/i2c/busses/i2c-bcm-iproc.c > @@ -233,13 +233,14 @@ static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c, > u32 offset) > { > u32 val; > + unsigned long flags; > > if (iproc_i2c->idm_base) { > - spin_lock(&iproc_i2c->idm_lock); > + spin_lock_irqsave(&iproc_i2c->idm_lock, flags); > writel(iproc_i2c->ape_addr_mask, > iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET); > val = readl(iproc_i2c->base + offset); > - spin_unlock(&iproc_i2c->idm_lock); > + spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags); > } else { > val = readl(iproc_i2c->base + offset); > } > @@ -250,12 +251,14 @@ static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c, > static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c, > u32 offset, u32 val) > { > + unsigned long flags; > + > if (iproc_i2c->idm_base) { > - spin_lock(&iproc_i2c->idm_lock); > + spin_lock_irqsave(&iproc_i2c->idm_lock, flags); > writel(iproc_i2c->ape_addr_mask, > iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET); > writel(val, iproc_i2c->base + offset); > - spin_unlock(&iproc_i2c->idm_lock); > + spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags); > } else { > writel(val, iproc_i2c->base + offset); > }
Acked-by: Ray Jui <ray.jui@broadcom.com>
Thanks, Chengfeng. [unhandled content-type:application/pkcs7-signature]
| |