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i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue

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commit 4caf4cb1eaed469742ef719f2cc024b1ec3fa9e6 upstream.

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>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Chengfeng Ye 2023-07-07 08:49:41 +00:00 committed by Greg Kroah-Hartman
parent b788ad3b24
commit 3259e2d878
1 changed files with 7 additions and 4 deletions
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11
drivers/i2c/busses/i2c-bcm-iproc.c
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@ -240,13 +240,14 @@ 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);
}
@ -257,12 +258,14 @@ 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);
}