From: Joakim Zhang <qiangqing.zhang@nxp.com>
To: "mkl@pengutronix.de" <mkl@pengutronix.de>,
"sean@geanix.com" <sean@geanix.com>,
"linux-can@vger.kernel.org" <linux-can@vger.kernel.org>
Cc: dl-linux-imx <linux-imx@nxp.com>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
Joakim Zhang <qiangqing.zhang@nxp.com>
Subject: [PATCH V2 3/4] can: flexcan: change the way of stop mode acknowledgment
Date: Wed, 27 Nov 2019 05:56:50 +0000 [thread overview]
Message-ID: <20191127055334.1476-4-qiangqing.zhang@nxp.com> (raw)
In-Reply-To: <20191127055334.1476-1-qiangqing.zhang@nxp.com>
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)
+{
+ 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)
--
2.17.1
next prev parent reply other threads:[~2019-11-27 5:56 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-27 5:56 [PATCH V2 0/4] can: flexcan: fixes for stop mode Joakim Zhang
2019-11-27 5:56 ` [PATCH V2 1/4] can: flexcan: fix deadlock when using self wakeup Joakim Zhang
2019-11-27 9:58 ` Sean Nyekjaer
2019-12-03 17:25 ` Marc Kleine-Budde
2019-12-03 17:42 ` Marc Kleine-Budde
2019-12-04 1:58 ` Joakim Zhang
2019-12-04 8:31 ` Marc Kleine-Budde
2019-12-04 8:35 ` Joakim Zhang
2019-11-27 5:56 ` [PATCH V2 2/4] can: flexcan: try to exit stop mode during probe stage Joakim Zhang
2019-11-27 9:58 ` Sean Nyekjaer
2019-12-03 18:14 ` Marc Kleine-Budde
2019-12-04 2:22 ` Joakim Zhang
2019-12-04 8:45 ` Marc Kleine-Budde
2019-12-04 9:58 ` Joakim Zhang
2019-12-05 8:46 ` Joakim Zhang
2019-12-05 9:21 ` Sean Nyekjaer
2019-12-05 11:04 ` Joakim Zhang
2019-12-05 11:11 ` Sean Nyekjaer
2019-12-05 11:19 ` Joakim Zhang
2019-12-05 11:32 ` Sean Nyekjaer
2019-12-07 20:32 ` Marc Kleine-Budde
2019-12-08 10:47 ` Sean Nyekjaer
2019-12-08 10:56 ` Marc Kleine-Budde
2019-11-27 5:56 ` Joakim Zhang [this message]
2019-11-27 9:58 ` [PATCH V2 3/4] can: flexcan: change the way of stop mode acknowledgment Sean Nyekjaer
2019-12-03 18:21 ` Marc Kleine-Budde
2019-12-04 2:23 ` Joakim Zhang
2019-11-27 5:56 ` [PATCH V2 4/4] can: flexcan: add LPSR mode support Joakim Zhang
2019-12-04 2:25 ` Joakim Zhang
2019-12-04 8:59 ` Marc Kleine-Budde
2019-12-04 9:58 ` Joakim Zhang
2019-12-04 9:20 ` Marc Kleine-Budde
2019-12-04 9:59 ` Joakim Zhang
2019-12-04 10:58 ` Joakim Zhang
2019-11-27 6:12 ` [PATCH V2 0/4] can: flexcan: fixes for stop mode Sean Nyekjaer
2019-11-27 8:12 ` Sean Nyekjaer
2019-11-27 9:36 ` Joakim Zhang
2019-11-27 9:48 ` Joakim Zhang
2019-11-27 9:52 ` Sean Nyekjaer
2019-11-27 9:58 ` Joakim Zhang
2019-11-27 9:59 ` Sean Nyekjaer
2019-11-27 10:04 ` Joakim Zhang
2019-12-03 10:16 ` Joakim Zhang
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