diff options
Diffstat (limited to 'drivers/net/can/flexcan.c')
| -rw-r--r-- | drivers/net/can/flexcan.c | 179 |
1 files changed, 136 insertions, 43 deletions
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index aaed97bee471..61376abdab39 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -144,6 +144,8 @@ #define FLEXCAN_MB_CODE_MASK (0xf0ffffff) +#define FLEXCAN_TIMEOUT_US (50) + /* * FLEXCAN hardware feature flags * @@ -235,9 +237,12 @@ static const struct can_bittiming_const flexcan_bittiming_const = { }; /* - * Abstract off the read/write for arm versus ppc. + * Abstract off the read/write for arm versus ppc. This + * assumes that PPC uses big-endian registers and everything + * else uses little-endian registers, independent of CPU + * endianess. */ -#if defined(__BIG_ENDIAN) +#if defined(CONFIG_PPC) static inline u32 flexcan_read(void __iomem *addr) { return in_be32(addr); @@ -259,6 +264,22 @@ static inline void flexcan_write(u32 val, void __iomem *addr) } #endif +static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv) +{ + if (!priv->reg_xceiver) + return 0; + + return regulator_enable(priv->reg_xceiver); +} + +static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv) +{ + if (!priv->reg_xceiver) + return 0; + + return regulator_disable(priv->reg_xceiver); +} + static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv, u32 reg_esr) { @@ -266,26 +287,95 @@ static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv, (reg_esr & FLEXCAN_ESR_ERR_BUS); } -static inline void flexcan_chip_enable(struct flexcan_priv *priv) +static int flexcan_chip_enable(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->base; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; u32 reg; reg = flexcan_read(®s->mcr); reg &= ~FLEXCAN_MCR_MDIS; flexcan_write(reg, ®s->mcr); - udelay(10); + while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + usleep_range(10, 20); + + if (flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK) + return -ETIMEDOUT; + + return 0; } -static inline void flexcan_chip_disable(struct flexcan_priv *priv) +static int flexcan_chip_disable(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->base; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; u32 reg; reg = flexcan_read(®s->mcr); reg |= FLEXCAN_MCR_MDIS; flexcan_write(reg, ®s->mcr); + + while (timeout-- && !(flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + usleep_range(10, 20); + + if (!(flexcan_read(®s->mcr) & FLEXCAN_MCR_LPM_ACK)) + return -ETIMEDOUT; + + return 0; +} + +static int flexcan_chip_freeze(struct flexcan_priv *priv) +{ + struct flexcan_regs __iomem *regs = priv->base; + unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate; + u32 reg; + + reg = flexcan_read(®s->mcr); + reg |= FLEXCAN_MCR_HALT; + flexcan_write(reg, ®s->mcr); + + while (timeout-- && !(flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)) + usleep_range(100, 200); + + if (!(flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)) + return -ETIMEDOUT; + + return 0; +} + +static int flexcan_chip_unfreeze(struct flexcan_priv *priv) +{ + struct flexcan_regs __iomem *regs = priv->base; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; + u32 reg; + + reg = flexcan_read(®s->mcr); + reg &= ~FLEXCAN_MCR_HALT; + flexcan_write(reg, ®s->mcr); + + while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)) + usleep_range(10, 20); + + if (flexcan_read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK) + return -ETIMEDOUT; + + return 0; +} + +static int flexcan_chip_softreset(struct flexcan_priv *priv) +{ + struct flexcan_regs __iomem *regs = priv->base; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; + + flexcan_write(FLEXCAN_MCR_SOFTRST, ®s->mcr); + while (timeout-- && (flexcan_read(®s->mcr) & FLEXCAN_MCR_SOFTRST)) + usleep_range(10, 20); + + if (flexcan_read(®s->mcr) & FLEXCAN_MCR_SOFTRST) + return -ETIMEDOUT; + + return 0; } static int flexcan_get_berr_counter(const struct net_device *dev, @@ -706,19 +796,14 @@ static int flexcan_chip_start(struct net_device *dev) u32 reg_mcr, reg_ctrl; /* enable module */ - flexcan_chip_enable(priv); + err = flexcan_chip_enable(priv); + if (err) + return err; /* soft reset */ - flexcan_write(FLEXCAN_MCR_SOFTRST, ®s->mcr); - udelay(10); - - reg_mcr = flexcan_read(®s->mcr); - if (reg_mcr & FLEXCAN_MCR_SOFTRST) { - netdev_err(dev, "Failed to softreset can module (mcr=0x%08x)\n", - reg_mcr); - err = -ENODEV; - goto out; - } + err = flexcan_chip_softreset(priv); + if (err) + goto out_chip_disable; flexcan_set_bittiming(dev); @@ -785,16 +870,14 @@ static int flexcan_chip_start(struct net_device *dev) if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES) flexcan_write(0x0, ®s->rxfgmask); - if (priv->reg_xceiver) { - err = regulator_enable(priv->reg_xceiver); - if (err) - goto out; - } + err = flexcan_transceiver_enable(priv); + if (err) + goto out_chip_disable; /* synchronize with the can bus */ - reg_mcr = flexcan_read(®s->mcr); - reg_mcr &= ~FLEXCAN_MCR_HALT; - flexcan_write(reg_mcr, ®s->mcr); + err = flexcan_chip_unfreeze(priv); + if (err) + goto out_transceiver_disable; priv->can.state = CAN_STATE_ERROR_ACTIVE; @@ -807,7 +890,9 @@ static int flexcan_chip_start(struct net_device *dev) return 0; - out: + out_transceiver_disable: + flexcan_transceiver_disable(priv); + out_chip_disable: flexcan_chip_disable(priv); return err; } @@ -822,18 +907,17 @@ static void flexcan_chip_stop(struct net_device *dev) { struct flexcan_priv *priv = netdev_priv(dev); struct flexcan_regs __iomem *regs = priv->base; - u32 reg; + + /* freeze + disable module */ + flexcan_chip_freeze(priv); + flexcan_chip_disable(priv); /* Disable all interrupts */ flexcan_write(0, ®s->imask1); + flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL, + ®s->ctrl); - /* Disable + halt module */ - reg = flexcan_read(®s->mcr); - reg |= FLEXCAN_MCR_MDIS | FLEXCAN_MCR_HALT; - flexcan_write(reg, ®s->mcr); - - if (priv->reg_xceiver) - regulator_disable(priv->reg_xceiver); + flexcan_transceiver_disable(priv); priv->can.state = CAN_STATE_STOPPED; return; @@ -863,7 +947,7 @@ static int flexcan_open(struct net_device *dev) /* start chip and queuing */ err = flexcan_chip_start(dev); if (err) - goto out_close; + goto out_free_irq; can_led_event(dev, CAN_LED_EVENT_OPEN); @@ -872,6 +956,8 @@ static int flexcan_open(struct net_device *dev) return 0; + out_free_irq: + free_irq(dev->irq, dev); out_close: close_candev(dev); out_disable_per: @@ -942,12 +1028,16 @@ static int register_flexcandev(struct net_device *dev) goto out_disable_ipg; /* select "bus clock", chip must be disabled */ - flexcan_chip_disable(priv); + err = flexcan_chip_disable(priv); + if (err) + goto out_disable_per; reg = flexcan_read(®s->ctrl); reg |= FLEXCAN_CTRL_CLK_SRC; flexcan_write(reg, ®s->ctrl); - flexcan_chip_enable(priv); + err = flexcan_chip_enable(priv); + if (err) + goto out_chip_disable; /* set freeze, halt and activate FIFO, restrict register access */ reg = flexcan_read(®s->mcr); @@ -964,14 +1054,15 @@ static int register_flexcandev(struct net_device *dev) if (!(reg & FLEXCAN_MCR_FEN)) { netdev_err(dev, "Could not enable RX FIFO, unsupported core\n"); err = -ENODEV; - goto out_disable_per; + goto out_chip_disable; } err = register_candev(dev); - out_disable_per: /* disable core and turn off clocks */ + out_chip_disable: flexcan_chip_disable(priv); + out_disable_per: clk_disable_unprepare(priv->clk_per); out_disable_ipg: clk_disable_unprepare(priv->clk_ipg); @@ -1101,9 +1192,10 @@ static int flexcan_probe(struct platform_device *pdev) static int flexcan_remove(struct platform_device *pdev) { struct net_device *dev = platform_get_drvdata(pdev); + struct flexcan_priv *priv = netdev_priv(dev); unregister_flexcandev(dev); - + netif_napi_del(&priv->napi); free_candev(dev); return 0; @@ -1114,8 +1206,11 @@ static int flexcan_suspend(struct device *device) { struct net_device *dev = dev_get_drvdata(device); struct flexcan_priv *priv = netdev_priv(dev); + int err; - flexcan_chip_disable(priv); + err = flexcan_chip_disable(priv); + if (err) + return err; if (netif_running(dev)) { netif_stop_queue(dev); @@ -1136,9 +1231,7 @@ static int flexcan_resume(struct device *device) netif_device_attach(dev); netif_start_queue(dev); } - flexcan_chip_enable(priv); - - return 0; + return flexcan_chip_enable(priv); } #endif /* CONFIG_PM_SLEEP */ |