| Message ID | 20191127055334.1476-4-qiangqing.zhang@nxp.com |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | David Miller |
| Headers | show |
| Series | can: flexcan: fixes for stop mode | expand |
On 27/11/2019 06.56, Joakim Zhang wrote: > Stop mode is entered when Stop mode is requested at chip level and > MCR[LPM_ACK] is asserted by the FlexCAN. > > Double check with IP owner, should poll MCR[LPM_ACK] for stop mode > acknowledgment, not the acknowledgment from chip level which is used > for glitch filter. > > Fixes: 5f186c257fa4(can: flexcan: fix stop mode acknowledgment) > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> Tested-by: Sean Nyekjaer <sean@geanix.com> > ------ > ChangeLog: > V1->V2: no change. > --- > drivers/net/can/flexcan.c | 64 ++++++++++++++++++++------------------- > 1 file changed, 33 insertions(+), 31 deletions(-) > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > index 5d5ed28d3005..d178146b3da5 100644 > --- a/drivers/net/can/flexcan.c > +++ b/drivers/net/can/flexcan.c > @@ -388,6 +388,34 @@ static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv > (&priv->regs->mb[bank][priv->mb_size * mb_index]); > } > > +static int flexcan_enter_low_power_ack(struct flexcan_priv *priv) > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + return -ETIMEDOUT; > + > + return 0; > +} > + > +static int flexcan_exit_low_power_ack(struct flexcan_priv *priv) > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > + return -ETIMEDOUT; > + > + return 0; > +} > + > static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > { > struct flexcan_regs __iomem *regs = priv->regs; > @@ -406,7 +434,6 @@ static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > reg_mcr = priv->read(®s->mcr); > @@ -418,35 +445,24 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); > > /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, ackval & (1 << priv->stm.ack_bit), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > /* remove stop request */ > regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, > 1 << priv->stm.req_bit, 0); > > - /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, !(ackval & (1 << priv->stm.ack_bit)), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > reg_mcr = priv->read(®s->mcr); > reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; > priv->write(reg_mcr, ®s->mcr); > > - return 0; > + /* get stop acknowledgment */ > + return flexcan_exit_low_power_ack(priv); > } > > static void flexcan_try_exit_stop_mode(struct flexcan_priv *priv) > @@ -512,39 +528,25 @@ static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv) > static int flexcan_chip_enable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg &= ~FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_exit_low_power_ack(priv); > } > > static int flexcan_chip_disable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg |= FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static int flexcan_chip_freeze(struct flexcan_priv *priv) >
On 11/27/19 6:56 AM, Joakim Zhang wrote: > Stop mode is entered when Stop mode is requested at chip level and > MCR[LPM_ACK] is asserted by the FlexCAN. > > Double check with IP owner, should poll MCR[LPM_ACK] for stop mode > acknowledgment, not the acknowledgment from chip level which is used > for glitch filter. > > Fixes: 5f186c257fa4(can: flexcan: fix stop mode acknowledgment) > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> > ------ > ChangeLog: > V1->V2: no change. > --- > drivers/net/can/flexcan.c | 64 ++++++++++++++++++++------------------- > 1 file changed, 33 insertions(+), 31 deletions(-) > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > index 5d5ed28d3005..d178146b3da5 100644 > --- a/drivers/net/can/flexcan.c > +++ b/drivers/net/can/flexcan.c > @@ -388,6 +388,34 @@ static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv > (&priv->regs->mb[bank][priv->mb_size * mb_index]); > } > > +static int flexcan_enter_low_power_ack(struct flexcan_priv *priv) nitpick: please call this flexcan_low_power_enter_ack() > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + return -ETIMEDOUT; > + > + return 0; > +} > + > +static int flexcan_exit_low_power_ack(struct flexcan_priv *priv) ...and this one flexcan_low_power_exit_ack() > +{ > + struct flexcan_regs __iomem *regs = priv->regs; > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > + > + while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > + udelay(10); > + > + if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > + return -ETIMEDOUT; > + > + return 0; > +} Can you move split the creation of flexcan_low_power_enter_ack()/flexcan_low_power_exit_ack() and use in flexcan_chip_enable/disable() into one patch and the conversion of flexcan_enter_stop_mode()/flexcan_exit_stop_mode() into another. Marc > + > static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > { > struct flexcan_regs __iomem *regs = priv->regs; > @@ -406,7 +434,6 @@ static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) > static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > reg_mcr = priv->read(®s->mcr); > @@ -418,35 +445,24 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) > 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); > > /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, ackval & (1 << priv->stm.ack_bit), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int ackval; > u32 reg_mcr; > > /* remove stop request */ > regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, > 1 << priv->stm.req_bit, 0); > > - /* get stop acknowledgment */ > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > - ackval, !(ackval & (1 << priv->stm.ack_bit)), > - 0, FLEXCAN_TIMEOUT_US)) > - return -ETIMEDOUT; > - > reg_mcr = priv->read(®s->mcr); > reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; > priv->write(reg_mcr, ®s->mcr); > > - return 0; > + /* get stop acknowledgment */ > + return flexcan_exit_low_power_ack(priv); > } > > static void flexcan_try_exit_stop_mode(struct flexcan_priv *priv) > @@ -512,39 +528,25 @@ static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv) > static int flexcan_chip_enable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg &= ~FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_exit_low_power_ack(priv); > } > > static int flexcan_chip_disable(struct flexcan_priv *priv) > { > struct flexcan_regs __iomem *regs = priv->regs; > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > u32 reg; > > reg = priv->read(®s->mcr); > reg |= FLEXCAN_MCR_MDIS; > priv->write(reg, ®s->mcr); > > - while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - udelay(10); > - > - if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > - return -ETIMEDOUT; > - > - return 0; > + return flexcan_enter_low_power_ack(priv); > } > > static int flexcan_chip_freeze(struct flexcan_priv *priv) >
> -----Original Message----- > From: Marc Kleine-Budde <mkl@pengutronix.de> > Sent: 2019年12月4日 2:22 > To: Joakim Zhang <qiangqing.zhang@nxp.com>; sean@geanix.com; > linux-can@vger.kernel.org > Cc: dl-linux-imx <linux-imx@nxp.com>; netdev@vger.kernel.org > Subject: Re: [PATCH V2 3/4] can: flexcan: change the way of stop mode > acknowledgment > > On 11/27/19 6:56 AM, Joakim Zhang wrote: > > Stop mode is entered when Stop mode is requested at chip level and > > MCR[LPM_ACK] is asserted by the FlexCAN. > > > > Double check with IP owner, should poll MCR[LPM_ACK] for stop mode > > acknowledgment, not the acknowledgment from chip level which is used > > for glitch filter. > > > > Fixes: 5f186c257fa4(can: flexcan: fix stop mode acknowledgment) > > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> > > ------ > > ChangeLog: > > V1->V2: no change. > > --- > > drivers/net/can/flexcan.c | 64 > > ++++++++++++++++++++------------------- > > 1 file changed, 33 insertions(+), 31 deletions(-) > > > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > > index 5d5ed28d3005..d178146b3da5 100644 > > --- a/drivers/net/can/flexcan.c > > +++ b/drivers/net/can/flexcan.c > > @@ -388,6 +388,34 @@ static struct flexcan_mb __iomem > *flexcan_get_mb(const struct flexcan_priv *priv > > (&priv->regs->mb[bank][priv->mb_size * mb_index]); } > > > > +static int flexcan_enter_low_power_ack(struct flexcan_priv *priv) > > nitpick: please call this flexcan_low_power_enter_ack() > > +{ > > + struct flexcan_regs __iomem *regs = priv->regs; > > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > > + > > + while (timeout-- && !(priv->read(®s->mcr) & > FLEXCAN_MCR_LPM_ACK)) > > + udelay(10); > > + > > + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > > + return -ETIMEDOUT; > > + > > + return 0; > > +} > > + > > +static int flexcan_exit_low_power_ack(struct flexcan_priv *priv) > > ...and this one flexcan_low_power_exit_ack() > > > +{ > > + struct flexcan_regs __iomem *regs = priv->regs; > > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > > + > > + while (timeout-- && (priv->read(®s->mcr) & > FLEXCAN_MCR_LPM_ACK)) > > + udelay(10); > > + > > + if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > > + return -ETIMEDOUT; > > + > > + return 0; > > +} > > Can you move split the creation of > flexcan_low_power_enter_ack()/flexcan_low_power_exit_ack() and use in > flexcan_chip_enable/disable() into one patch and the conversion of > flexcan_enter_stop_mode()/flexcan_exit_stop_mode() into another. Of course, this could be more clearer and reasonable. Thanks. Best Regards, Joakim Zhang > Marc > > > + > > static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool > > enable) { > > struct flexcan_regs __iomem *regs = priv->regs; @@ -406,7 +434,6 @@ > > static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool > > enable) static inline int flexcan_enter_stop_mode(struct flexcan_priv > > *priv) { > > struct flexcan_regs __iomem *regs = priv->regs; > > - unsigned int ackval; > > u32 reg_mcr; > > > > reg_mcr = priv->read(®s->mcr); > > @@ -418,35 +445,24 @@ static inline int flexcan_enter_stop_mode(struct > flexcan_priv *priv) > > 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); > > > > /* get stop acknowledgment */ > > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > > - ackval, ackval & (1 << priv->stm.ack_bit), > > - 0, FLEXCAN_TIMEOUT_US)) > > - return -ETIMEDOUT; > > - > > - return 0; > > + return flexcan_enter_low_power_ack(priv); > > } > > > > static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) > > { > > struct flexcan_regs __iomem *regs = priv->regs; > > - unsigned int ackval; > > u32 reg_mcr; > > > > /* remove stop request */ > > regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, > > 1 << priv->stm.req_bit, 0); > > > > - /* get stop acknowledgment */ > > - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, > > - ackval, !(ackval & (1 << priv->stm.ack_bit)), > > - 0, FLEXCAN_TIMEOUT_US)) > > - return -ETIMEDOUT; > > - > > reg_mcr = priv->read(®s->mcr); > > reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; > > priv->write(reg_mcr, ®s->mcr); > > > > - return 0; > > + /* get stop acknowledgment */ > > + return flexcan_exit_low_power_ack(priv); > > } > > > > static void flexcan_try_exit_stop_mode(struct flexcan_priv *priv) @@ > > -512,39 +528,25 @@ static inline int flexcan_transceiver_disable(const > > struct flexcan_priv *priv) static int flexcan_chip_enable(struct > > flexcan_priv *priv) { > > struct flexcan_regs __iomem *regs = priv->regs; > > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > > u32 reg; > > > > reg = priv->read(®s->mcr); > > reg &= ~FLEXCAN_MCR_MDIS; > > priv->write(reg, ®s->mcr); > > > > - while (timeout-- && (priv->read(®s->mcr) & > FLEXCAN_MCR_LPM_ACK)) > > - udelay(10); > > - > > - if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) > > - return -ETIMEDOUT; > > - > > - return 0; > > + return flexcan_exit_low_power_ack(priv); > > } > > > > static int flexcan_chip_disable(struct flexcan_priv *priv) { > > struct flexcan_regs __iomem *regs = priv->regs; > > - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > > u32 reg; > > > > reg = priv->read(®s->mcr); > > reg |= FLEXCAN_MCR_MDIS; > > priv->write(reg, ®s->mcr); > > > > - while (timeout-- && !(priv->read(®s->mcr) & > FLEXCAN_MCR_LPM_ACK)) > > - udelay(10); > > - > > - if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) > > - return -ETIMEDOUT; > > - > > - return 0; > > + return flexcan_enter_low_power_ack(priv); > > } > > > > static int flexcan_chip_freeze(struct flexcan_priv *priv) > > > > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Embedded Linux | https://www.pengutronix.de | > Vertretung West/Dortmund | Phone: +49-231-2826-924 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 5d5ed28d3005..d178146b3da5 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -388,6 +388,34 @@ static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv (&priv->regs->mb[bank][priv->mb_size * mb_index]); } +static int flexcan_enter_low_power_ack(struct flexcan_priv *priv) +{ + struct flexcan_regs __iomem *regs = priv->regs; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; + + while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + udelay(10); + + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + return -ETIMEDOUT; + + return 0; +} + +static int flexcan_exit_low_power_ack(struct flexcan_priv *priv) +{ + struct flexcan_regs __iomem *regs = priv->regs; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; + + while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + udelay(10); + + if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) + return -ETIMEDOUT; + + return 0; +} + static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) { struct flexcan_regs __iomem *regs = priv->regs; @@ -406,7 +434,6 @@ static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable) static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; - unsigned int ackval; u32 reg_mcr; reg_mcr = priv->read(®s->mcr); @@ -418,35 +445,24 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); /* get stop acknowledgment */ - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, - ackval, ackval & (1 << priv->stm.ack_bit), - 0, FLEXCAN_TIMEOUT_US)) - return -ETIMEDOUT; - - return 0; + return flexcan_enter_low_power_ack(priv); } static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; - unsigned int ackval; u32 reg_mcr; /* remove stop request */ regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, 1 << priv->stm.req_bit, 0); - /* get stop acknowledgment */ - if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, - ackval, !(ackval & (1 << priv->stm.ack_bit)), - 0, FLEXCAN_TIMEOUT_US)) - return -ETIMEDOUT; - reg_mcr = priv->read(®s->mcr); reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; priv->write(reg_mcr, ®s->mcr); - return 0; + /* get stop acknowledgment */ + return flexcan_exit_low_power_ack(priv); } static void flexcan_try_exit_stop_mode(struct flexcan_priv *priv) @@ -512,39 +528,25 @@ static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv) static int flexcan_chip_enable(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; u32 reg; reg = priv->read(®s->mcr); reg &= ~FLEXCAN_MCR_MDIS; priv->write(reg, ®s->mcr); - while (timeout-- && (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) - udelay(10); - - if (priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) - return -ETIMEDOUT; - - return 0; + return flexcan_exit_low_power_ack(priv); } static int flexcan_chip_disable(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; - unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; u32 reg; reg = priv->read(®s->mcr); reg |= FLEXCAN_MCR_MDIS; priv->write(reg, ®s->mcr); - while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) - udelay(10); - - if (!(priv->read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) - return -ETIMEDOUT; - - return 0; + return flexcan_enter_low_power_ack(priv); } static int flexcan_chip_freeze(struct flexcan_priv *priv)
Stop mode is entered when Stop mode is requested at chip level and MCR[LPM_ACK] is asserted by the FlexCAN. Double check with IP owner, should poll MCR[LPM_ACK] for stop mode acknowledgment, not the acknowledgment from chip level which is used for glitch filter. Fixes: 5f186c257fa4(can: flexcan: fix stop mode acknowledgment) Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> ------ ChangeLog: V1->V2: no change. --- drivers/net/can/flexcan.c | 64 ++++++++++++++++++++------------------- 1 file changed, 33 insertions(+), 31 deletions(-)