diff options
| author | Mirza Krak <mirza.krak@hostmobility.com> | 2014-08-08 14:30:50 +0200 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2014-08-21 10:49:34 +0200 |
| commit | 9e37bc6c635a85e0ae3067f19d6f84e1c4516a6c (patch) | |
| tree | b2d78309495db7433d427c35f463727e18faf4ab | |
| parent | 02784f1b05b8f241c8180af88869e717e2758593 (diff) | |
can: sja1000: Validate initialization state in start method
When sja1000 is not compiled as module the SJA1000 chip is only
initialized during device registration on kernel boot. Should the chip
get a hardware reset there is no way to reinitialize it without re-
booting the Linux kernel.
This patch adds a check in sja1000_start if the chip is initialized, if
not we initialize it.
Signed-off-by: Mirza Krak <mirza.krak@hostmobility.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | drivers/net/can/sja1000/sja1000.c | 62 |
1 files changed, 33 insertions, 29 deletions
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index d1692154ed1b..b27ac6074afb 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -172,6 +172,35 @@ static void set_normal_mode(struct net_device *dev) netdev_err(dev, "setting SJA1000 into normal mode failed!\n"); } +/* + * initialize SJA1000 chip: + * - reset chip + * - set output mode + * - set baudrate + * - enable interrupts + * - start operating mode + */ +static void chipset_init(struct net_device *dev) +{ + struct sja1000_priv *priv = netdev_priv(dev); + + /* set clock divider and output control register */ + priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN); + + /* set acceptance filter (accept all) */ + priv->write_reg(priv, SJA1000_ACCC0, 0x00); + priv->write_reg(priv, SJA1000_ACCC1, 0x00); + priv->write_reg(priv, SJA1000_ACCC2, 0x00); + priv->write_reg(priv, SJA1000_ACCC3, 0x00); + + priv->write_reg(priv, SJA1000_ACCM0, 0xFF); + priv->write_reg(priv, SJA1000_ACCM1, 0xFF); + priv->write_reg(priv, SJA1000_ACCM2, 0xFF); + priv->write_reg(priv, SJA1000_ACCM3, 0xFF); + + priv->write_reg(priv, SJA1000_OCR, priv->ocr | OCR_MODE_NORMAL); +} + static void sja1000_start(struct net_device *dev) { struct sja1000_priv *priv = netdev_priv(dev); @@ -180,6 +209,10 @@ static void sja1000_start(struct net_device *dev) if (priv->can.state != CAN_STATE_STOPPED) set_reset_mode(dev); + /* Initialize chip if uninitialized at this stage */ + if (!(priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN)) + chipset_init(dev); + /* Clear error counters and error code capture */ priv->write_reg(priv, SJA1000_TXERR, 0x0); priv->write_reg(priv, SJA1000_RXERR, 0x0); @@ -237,35 +270,6 @@ static int sja1000_get_berr_counter(const struct net_device *dev, } /* - * initialize SJA1000 chip: - * - reset chip - * - set output mode - * - set baudrate - * - enable interrupts - * - start operating mode - */ -static void chipset_init(struct net_device *dev) -{ - struct sja1000_priv *priv = netdev_priv(dev); - - /* set clock divider and output control register */ - priv->write_reg(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN); - - /* set acceptance filter (accept all) */ - priv->write_reg(priv, SJA1000_ACCC0, 0x00); - priv->write_reg(priv, SJA1000_ACCC1, 0x00); - priv->write_reg(priv, SJA1000_ACCC2, 0x00); - priv->write_reg(priv, SJA1000_ACCC3, 0x00); - - priv->write_reg(priv, SJA1000_ACCM0, 0xFF); - priv->write_reg(priv, SJA1000_ACCM1, 0xFF); - priv->write_reg(priv, SJA1000_ACCM2, 0xFF); - priv->write_reg(priv, SJA1000_ACCM3, 0xFF); - - priv->write_reg(priv, SJA1000_OCR, priv->ocr | OCR_MODE_NORMAL); -} - -/* * transmit a CAN message * message layout in the sk_buff should be like this: * xx xx xx xx ff ll 00 11 22 33 44 55 66 77 |