diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/imx.c | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 34185991f872..f34200a4613f 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -758,21 +758,47 @@ static void imx_mctrl_check(struct imx_port *sport) static irqreturn_t imx_int(int irq, void *dev_id) { struct imx_port *sport = dev_id; - unsigned int usr1, usr2; + unsigned int usr1, usr2, ucr1, ucr2, ucr3, ucr4; irqreturn_t ret = IRQ_NONE; usr1 = readl(sport->port.membase + USR1); usr2 = readl(sport->port.membase + USR2); + ucr1 = readl(sport->port.membase + UCR1); + ucr2 = readl(sport->port.membase + UCR2); + ucr3 = readl(sport->port.membase + UCR3); + ucr4 = readl(sport->port.membase + UCR4); - if (!sport->dma_is_enabled && (usr1 & (USR1_RRDY | USR1_AGTIM))) { + /* + * Even if a condition is true that can trigger an irq only handle it if + * the respective irq source is enabled. This prevents some undesired + * actions, for example if a character that sits in the RX FIFO and that + * should be fetched via DMA is tried to be fetched using PIO. Or the + * receiver is currently off and so reading from URXD0 results in an + * exception. So just mask the (raw) status bits for disabled irqs. + */ + if ((ucr1 & UCR1_RRDYEN) == 0) + usr1 &= ~USR1_RRDY; + if ((ucr2 & UCR2_ATEN) == 0) + usr1 &= ~USR1_AGTIM; + if ((ucr1 & UCR1_TXMPTYEN) == 0) + usr1 &= ~USR1_TRDY; + if ((ucr4 & UCR4_TCEN) == 0) + usr2 &= ~USR2_TXDC; + if ((ucr3 & UCR3_DTRDEN) == 0) + usr1 &= ~USR1_DTRD; + if ((ucr1 & UCR1_RTSDEN) == 0) + usr1 &= ~USR1_RTSD; + if ((ucr3 & UCR3_AWAKEN) == 0) + usr1 &= ~USR1_AWAKE; + if ((ucr4 & UCR4_OREN) == 0) + usr2 &= ~USR2_ORE; + + if (usr1 & (USR1_RRDY | USR1_AGTIM)) { imx_rxint(irq, dev_id); ret = IRQ_HANDLED; } - if ((usr1 & USR1_TRDY && - readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN) || - (usr2 & USR2_TXDC && - readl(sport->port.membase + UCR4) & UCR4_TCEN)) { + if ((usr1 & USR1_TRDY) || (usr2 & USR2_TXDC)) { imx_txint(irq, dev_id); ret = IRQ_HANDLED; } |