[Blackfin] serial driver: fix bug - cache the bits of the LSR on systems where the LSR is read-to-clear
Cache the bits of the LSR on systems where the LSR is read-to-clear
so that we can safely read the LSR in random places. this fixes
older parts where break/framing/parity/overflow was not being detected
at all in PIO mode, and this fixes newer parts where
break/framing/parity/overflow was being reported all the time
without being cleared.
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index ca9ceaa..af84984 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -216,8 +216,10 @@
struct pt_regs *regs = get_irq_regs();
#endif
- ch = UART_GET_CHAR(uart);
status = UART_GET_LSR(uart);
+ UART_CLEAR_LSR(uart);
+
+ ch = UART_GET_CHAR(uart);
uart->port.icount.rx++;
#ifdef CONFIG_KGDB_UART
@@ -335,7 +337,7 @@
struct bfin_serial_port *uart = dev_id;
spin_lock(&uart->port.lock);
- while ((UART_GET_IER(uart) & ERBFI) && (UART_GET_LSR(uart) & DR))
+ while (UART_GET_LSR(uart) & DR)
bfin_serial_rx_chars(uart);
spin_unlock(&uart->port.lock);
@@ -347,7 +349,7 @@
struct bfin_serial_port *uart = dev_id;
spin_lock(&uart->port.lock);
- if ((UART_GET_IER(uart) & ETBEI) && (UART_GET_LSR(uart) & THRE))
+ if (UART_GET_LSR(uart) & THRE)
bfin_serial_tx_chars(uart);
spin_unlock(&uart->port.lock);
@@ -428,6 +430,8 @@
int i, flg, status;
status = UART_GET_LSR(uart);
+ UART_CLEAR_LSR(uart);
+
uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
if (status & BI) {