UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

can: flexcan: add low power enter/exit acknowledgment helper 

The MCR[LPMACK] read-only bit indicates that FlexCAN is in a lower-power
mode (Disabled mode, Doze mode, Stop mode).

The CPU can poll this bit to know when FlexCAN has actually entered low
power mode. The low power enter/exit acknowledgment helper will reduce
code duplication for disabled mode, doze mode and stop mode.

Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Joakim Zhang 2019-12-04 11:36:11 +00:00 committed by Marc Kleine-Budde
parent e707180ae2
commit b7603d080f
1 changed files with 30 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
drivers/net/can/flexcan.c
View File

@ -389,6 +389,34 @@ 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_low_power_enter_ack(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
return -ETIMEDOUT;
return 0;
}
static int flexcan_low_power_exit_ack(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (priv->read(&regs->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;
@ -506,39 +534,25 @@ 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(&regs->mcr);
reg &= ~FLEXCAN_MCR_MDIS;
priv->write(reg, &regs->mcr);
while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
return -ETIMEDOUT;
return 0;
return flexcan_low_power_exit_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(&regs->mcr);
reg |= FLEXCAN_MCR_MDIS;
priv->write(reg, &regs->mcr);
while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
return -ETIMEDOUT;
return 0;
return flexcan_low_power_enter_ack(priv);
}
static int flexcan_chip_freeze(struct flexcan_priv *priv)