lkml.org 
[lkml]   [2015]   [Dec]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH LINUX v5 8/8] tty: xuartps: Move RX path into helper function
Date
Move RX-related IRQ handling into a helper function.
Fixes a problem where every char received after a parity or frame error
in the current isr will also be tagged as a parity or frame error.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
---
v4:
- added Peter's additional information to the commit message (thx)
---
drivers/tty/serial/xilinx_uartps.c | 50 +++++++++++++++++++++-----------------
1 file changed, 28 insertions(+), 22 deletions(-)

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index f3ac69387b0a..db9e23eaf300 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -172,28 +172,8 @@ struct cdns_uart {
#define to_cdns_uart(_nb) container_of(_nb, struct cdns_uart, \
clk_rate_change_nb);

-/**
- * cdns_uart_isr - Interrupt handler
- * @irq: Irq number
- * @dev_id: Id of the port
- *
- * Return: IRQHANDLED
- */
-static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
+static void cdns_uart_handle_rx(struct uart_port *port, unsigned int isrstatus)
{
- struct uart_port *port = (struct uart_port *)dev_id;
- unsigned long flags;
- unsigned int isrstatus, numbytes;
- unsigned int data;
- char status = TTY_NORMAL;
-
- spin_lock_irqsave(&port->lock, flags);
-
- /* Read the interrupt status register to determine which
- * interrupt(s) is/are active.
- */
- isrstatus = readl(port->membase + CDNS_UART_ISR_OFFSET);
-
/*
* There is no hardware break detection, so we interpret framing
* error with all-zeros data as a break sequence. Most of the time,
@@ -223,6 +203,9 @@ static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
/* Receive Timeout Interrupt */
while (!(readl(port->membase + CDNS_UART_SR_OFFSET) &
CDNS_UART_SR_RXEMPTY)) {
+ u32 data;
+ char status = TTY_NORMAL;
+
data = readl(port->membase + CDNS_UART_FIFO_OFFSET);

/* Non-NULL byte after BREAK is garbage (99%) */
@@ -263,10 +246,33 @@ static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
}

uart_insert_char(port, isrstatus, CDNS_UART_IXR_OVERRUN,
- data, status);
+ data, status);
}
tty_flip_buffer_push(&port->state->port);
}
+}
+
+/**
+ * cdns_uart_isr - Interrupt handler
+ * @irq: Irq number
+ * @dev_id: Id of the port
+ *
+ * Return: IRQHANDLED
+ */
+static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
+{
+ struct uart_port *port = (struct uart_port *)dev_id;
+ unsigned long flags;
+ unsigned int isrstatus, numbytes;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Read the interrupt status register to determine which
+ * interrupt(s) is/are active.
+ */
+ isrstatus = readl(port->membase + CDNS_UART_ISR_OFFSET);
+
+ cdns_uart_handle_rx(port, isrstatus);

/* Dispatch an appropriate handler */
if ((isrstatus & CDNS_UART_IXR_TXEMPTY) == CDNS_UART_IXR_TXEMPTY) {
--
2.6.3.3.g9bb996a


\
 
 \ /
  Last update: 2015-12-26 12:01    [W:0.099 / U:0.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site