Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3259e2d8 authored by Chengfeng Ye's avatar Chengfeng Ye Committed by Greg Kroah-Hartman
Browse files

i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue 



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: 9a103872 ("i2c: iproc: add NIC I2C support")
Signed-off-by: default avatarChengfeng Ye <dg573847474@gmail.com>
Acked-by: default avatarRay Jui <ray.jui@broadcom.com>
Reviewed-by: default avatarAndi Shyti <andi.shyti@kernel.org>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent b788ad3b

drivers/i2c/busses/i2c-bcm-iproc.c

+7 −4
Original line number Diff line number Diff line
@@ -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);

	}