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path: root/drivers/net/can/flexcan.c
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Diffstat (limited to 'drivers/net/can/flexcan.c')
-rw-r--r--drivers/net/can/flexcan.c179
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(&regs->mcr);
reg &= ~FLEXCAN_MCR_MDIS;
flexcan_write(reg, &regs->mcr);
- udelay(10);
+ while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
+ usleep_range(10, 20);
+
+ if (flexcan_read(&regs->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(&regs->mcr);
reg |= FLEXCAN_MCR_MDIS;
flexcan_write(reg, &regs->mcr);
+
+ while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
+ usleep_range(10, 20);
+
+ if (!(flexcan_read(&regs->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(&regs->mcr);
+ reg |= FLEXCAN_MCR_HALT;
+ flexcan_write(reg, &regs->mcr);
+
+ while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
+ usleep_range(100, 200);
+
+ if (!(flexcan_read(&regs->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(&regs->mcr);
+ reg &= ~FLEXCAN_MCR_HALT;
+ flexcan_write(reg, &regs->mcr);
+
+ while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
+ usleep_range(10, 20);
+
+ if (flexcan_read(&regs->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, &regs->mcr);
+ while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
+ usleep_range(10, 20);
+
+ if (flexcan_read(&regs->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, &regs->mcr);
- udelay(10);
-
- reg_mcr = flexcan_read(&regs->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, &regs->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(&regs->mcr);
- reg_mcr &= ~FLEXCAN_MCR_HALT;
- flexcan_write(reg_mcr, &regs->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, &regs->imask1);
+ flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
+ &regs->ctrl);
- /* Disable + halt module */
- reg = flexcan_read(&regs->mcr);
- reg |= FLEXCAN_MCR_MDIS | FLEXCAN_MCR_HALT;
- flexcan_write(reg, &regs->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(&regs->ctrl);
reg |= FLEXCAN_CTRL_CLK_SRC;
flexcan_write(reg, &regs->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(&regs->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 */