The patch titled blackfin serial driver: fix bug - serial port transfer big file from host to target would have more lines has been added to the -mm tree. Its filename is blackfin-serial-driver-fix-bug-serial-port-transfer-big-file-from-host-to-target-would-have-more-lines.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: blackfin serial driver: fix bug - serial port transfer big file from host to target would have more lines From: Sonic Zhang <sonic.zhang@xxxxxxxxxx> Ignore receiving data if new position is in the same line of current buffer tail and small. Signed-off-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx> Signed-off-by: Bryan Wu <cooloney@xxxxxxxxxx> Cc: Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/serial/bfin_5xx.c | 31 +++++++++++++++++++++++++++++-- 1 file changed, 29 insertions(+), 2 deletions(-) diff -puN drivers/serial/bfin_5xx.c~blackfin-serial-driver-fix-bug-serial-port-transfer-big-file-from-host-to-target-would-have-more-lines drivers/serial/bfin_5xx.c --- a/drivers/serial/bfin_5xx.c~blackfin-serial-driver-fix-bug-serial-port-transfer-big-file-from-host-to-target-would-have-more-lines +++ a/drivers/serial/bfin_5xx.c @@ -407,6 +407,15 @@ void bfin_serial_rx_dma_timeout(struct b spin_lock_irqsave(&uart->port.lock, flags); + /* 2D DMA RX buffer ring is used. Because curr_y_count and + * curr_x_count can't be read as an atomic operation, + * curr_y_count should be read before curr_x_count. When + * curr_x_count is read, curr_y_count may already indicate + * next buffer line. But, the position calculated here is + * still indicate the old line. The wrong position data may + * be smaller than current buffer tail, which cause garbages + * are received if it is not prohibit. + */ uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel); x_pos = get_dma_curr_xcount(uart->rx_dma_channel); uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows; @@ -417,7 +426,11 @@ void bfin_serial_rx_dma_timeout(struct b x_pos = 0; pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos; - if (pos != uart->rx_dma_buf.tail) { + /* Ignore receiving data if new position is in the same line of + * current buffer tail and small. + */ + if (pos > uart->rx_dma_buf.tail || + uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) { uart->rx_dma_buf.head = pos; bfin_serial_dma_rx_chars(uart); uart->rx_dma_buf.tail = uart->rx_dma_buf.head; @@ -455,11 +468,25 @@ static irqreturn_t bfin_serial_dma_rx_in { struct bfin_serial_port *uart = dev_id; unsigned short irqstat; + int pos; spin_lock(&uart->port.lock); irqstat = get_dma_curr_irqstat(uart->rx_dma_channel); clear_dma_irqstat(uart->rx_dma_channel); - bfin_serial_dma_rx_chars(uart); + + uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel); + uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows; + if (uart->rx_dma_nrows == DMA_RX_YCOUNT) + uart->rx_dma_nrows = 0; + + pos = uart->rx_dma_nrows * DMA_RX_XCOUNT; + if (pos > uart->rx_dma_buf.tail || + uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) { + uart->rx_dma_buf.head = pos; + bfin_serial_dma_rx_chars(uart); + uart->rx_dma_buf.tail = uart->rx_dma_buf.head; + } + spin_unlock(&uart->port.lock); return IRQ_HANDLED; _ Patches currently in -mm which might be from sonic.zhang@xxxxxxxxxx are linux-next.patch blackfin-serial-driver-fix-a-bug-in-dma-circle-rx-buffer-handling.patch blackfin-serial-driver-change-hardware-flowcontrol-from-poll-to-interrupt-driven.patch blackfin-serial-driver-fix-bug-serial-port-transfer-big-file-from-host-to-target-would-have-more-lines.patch blackfin-serial-driver-fix-compile-error-in-pio-mode.patch blackfin-serial-driver-fix-bug-enable-hardware-based-cts-and-rts-for-bf548.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html