The bfin-uart code uses real time with struct timeval. This will cause problems on 32-bit architectures in 2038 when time_t overflows. Since the code just needs delta value of time, it is not necessary to record them in real time. This patch changes the code to use the monotonic time instead, replaces do_gettimeofday() and struct timeval with ktime_get() and ktime_t.
Signed-off-by: DengChao chao.deng@linaro.org --- drivers/tty/serial/bfin_uart.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-)
diff --git a/drivers/tty/serial/bfin_uart.c b/drivers/tty/serial/bfin_uart.c index ae3cf94..abfb988 100644 --- a/drivers/tty/serial/bfin_uart.c +++ b/drivers/tty/serial/bfin_uart.c @@ -213,7 +213,7 @@ static void bfin_serial_stop_rx(struct uart_port *port) static void bfin_serial_rx_chars(struct bfin_serial_port *uart) { unsigned int status, ch, flg; - static struct timeval anomaly_start = { .tv_sec = 0 }; + static time64_t anomaly_start;
status = UART_GET_LSR(uart); UART_CLEAR_LSR(uart); @@ -246,42 +246,40 @@ static void bfin_serial_rx_chars(struct bfin_serial_port *uart) * character time +/- some percent. So 1.5 sounds good. All other * Blackfin families operate properly. Woo. */ - if (anomaly_start.tv_sec) { - struct timeval curr; - suseconds_t usecs; + if (anomaly_start >= NSEC_PER_SEC) { + ktime_t curr; + time64_t nsecs, threshold_ns;
if ((~ch & (~ch + 1)) & 0xff) goto known_good_char;
- do_gettimeofday(&curr); - if (curr.tv_sec - anomaly_start.tv_sec > 1) + curr = ktime_get(); + nsecs = ktime_to_ns(ktime_sub_ns(curr, anomaly_start)); + if (nsecs > NSEC_PER_SEC) goto known_good_char;
- usecs = 0; - if (curr.tv_sec != anomaly_start.tv_sec) - usecs += USEC_PER_SEC; - usecs += curr.tv_usec - anomaly_start.tv_usec; - - if (usecs > UART_GET_ANOMALY_THRESHOLD(uart)) + threshold_ns = UART_GET_ANOMALY_THRESHOLD(uart) + * NSEC_PER_USEC; + if (nsecs > threshold_ns) goto known_good_char;
if (ch) - anomaly_start.tv_sec = 0; + anomaly_start = 0; else - anomaly_start = curr; + anomaly_start = ktime_to_ns(curr);
return;
known_good_char: status &= ~BI; - anomaly_start.tv_sec = 0; + anomaly_start = 0; } }
if (status & BI) { if (ANOMALY_05000363) if (bfin_revid() < 5) - do_gettimeofday(&anomaly_start); + anomaly_start = ktime_to_ns(ktime_get()); uart->port.icount.brk++; if (uart_handle_break(&uart->port)) goto ignore_char;