diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 82 |
1 files changed, 33 insertions, 49 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 042aa077b5b3..b2cfdb661947 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -223,8 +223,7 @@ struct imx_port { struct dma_chan *dma_chan_rx, *dma_chan_tx; struct scatterlist rx_sgl, tx_sgl[2]; void *rx_buf; - unsigned int rx_bytes, tx_bytes; - struct work_struct tsk_dma_rx, tsk_dma_tx; + unsigned int tx_bytes; unsigned int dma_tx_nents; wait_queue_head_t dma_wait; }; @@ -505,34 +504,25 @@ static void dma_tx_callback(void *data) dev_dbg(sport->port.dev, "exit in %s.\n", __func__); return; } - - schedule_work(&sport->tsk_dma_tx); } -static void dma_tx_work(struct work_struct *w) +static void imx_dma_tx(struct imx_port *sport) { - struct imx_port *sport = container_of(w, struct imx_port, tsk_dma_tx); struct circ_buf *xmit = &sport->port.state->xmit; struct scatterlist *sgl = sport->tx_sgl; struct dma_async_tx_descriptor *desc; struct dma_chan *chan = sport->dma_chan_tx; struct device *dev = sport->port.dev; enum dma_status status; - unsigned long flags; int ret; - status = chan->device->device_tx_status(chan, (dma_cookie_t)0, NULL); + status = dmaengine_tx_status(chan, (dma_cookie_t)0, NULL); if (DMA_IN_PROGRESS == status) return; - spin_lock_irqsave(&sport->port.lock, flags); sport->tx_bytes = uart_circ_chars_pending(xmit); - if (sport->tx_bytes == 0) { - spin_unlock_irqrestore(&sport->port.lock, flags); - return; - } - if (xmit->tail > xmit->head) { + if (xmit->tail > xmit->head && xmit->head > 0) { sport->dma_tx_nents = 2; sg_init_table(sgl, 2); sg_set_buf(sgl, xmit->buf + xmit->tail, @@ -542,7 +532,6 @@ static void dma_tx_work(struct work_struct *w) sport->dma_tx_nents = 1; sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes); } - spin_unlock_irqrestore(&sport->port.lock, flags); ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE); if (ret == 0) { @@ -609,11 +598,7 @@ static void imx_start_tx(struct uart_port *port) } if (sport->dma_is_enabled) { - /* - * We may in the interrupt context, so arise a work_struct to - * do the real job. - */ - schedule_work(&sport->tsk_dma_tx); + imx_dma_tx(sport); return; } @@ -732,6 +717,7 @@ out: return IRQ_HANDLED; } +static int start_rx_dma(struct imx_port *sport); /* * If the RXFIFO is filled with some data, and then we * arise a DMA operation to receive them. @@ -750,7 +736,7 @@ static void imx_dma_rxint(struct imx_port *sport) writel(temp, sport->port.membase + UCR1); /* tell the DMA to receive the data. */ - schedule_work(&sport->tsk_dma_rx); + start_rx_dma(sport); } } @@ -795,8 +781,15 @@ static irqreturn_t imx_int(int irq, void *dev_id) static unsigned int imx_tx_empty(struct uart_port *port) { struct imx_port *sport = (struct imx_port *)port; + unsigned int ret; + + ret = (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0; - return (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0; + /* If the TX DMA is working, return 0. */ + if (sport->dma_is_enabled && sport->dma_is_txing) + ret = 0; + + return ret; } /* @@ -865,22 +858,6 @@ static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode) } #define RX_BUF_SIZE (PAGE_SIZE) -static int start_rx_dma(struct imx_port *sport); -static void dma_rx_work(struct work_struct *w) -{ - struct imx_port *sport = container_of(w, struct imx_port, tsk_dma_rx); - struct tty_port *port = &sport->port.state->port; - - if (sport->rx_bytes) { - tty_insert_flip_string(port, sport->rx_buf, sport->rx_bytes); - tty_flip_buffer_push(port); - sport->rx_bytes = 0; - } - - if (sport->dma_is_rxing) - start_rx_dma(sport); -} - static void imx_rx_dma_done(struct imx_port *sport) { unsigned long temp; @@ -912,6 +889,7 @@ static void dma_rx_callback(void *data) struct imx_port *sport = data; struct dma_chan *chan = sport->dma_chan_rx; struct scatterlist *sgl = &sport->rx_sgl; + struct tty_port *port = &sport->port.state->port; struct dma_tx_state state; enum dma_status status; unsigned int count; @@ -919,13 +897,15 @@ static void dma_rx_callback(void *data) /* unmap it first */ dma_unmap_sg(sport->port.dev, sgl, 1, DMA_FROM_DEVICE); - status = chan->device->device_tx_status(chan, (dma_cookie_t)0, &state); + status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state); count = RX_BUF_SIZE - state.residue; dev_dbg(sport->port.dev, "We get %d bytes.\n", count); if (count) { - sport->rx_bytes = count; - schedule_work(&sport->tsk_dma_rx); + tty_insert_flip_string(port, sport->rx_buf, count); + tty_flip_buffer_push(port); + + start_rx_dma(sport); } else imx_rx_dma_done(sport); } @@ -1007,7 +987,6 @@ static int imx_uart_dma_init(struct imx_port *sport) ret = -ENOMEM; goto err; } - sport->rx_bytes = 0; /* Prepare for TX : */ sport->dma_chan_tx = dma_request_slave_channel(dev, "tx"); @@ -1038,11 +1017,7 @@ err: static void imx_enable_dma(struct imx_port *sport) { unsigned long temp; - struct tty_port *port = &sport->port.state->port; - port->low_latency = 1; - INIT_WORK(&sport->tsk_dma_tx, dma_tx_work); - INIT_WORK(&sport->tsk_dma_rx, dma_rx_work); init_waitqueue_head(&sport->dma_wait); /* set UCR1 */ @@ -1063,7 +1038,6 @@ static void imx_enable_dma(struct imx_port *sport) static void imx_disable_dma(struct imx_port *sport) { unsigned long temp; - struct tty_port *port = &sport->port.state->port; /* clear UCR1 */ temp = readl(sport->port.membase + UCR1); @@ -1081,7 +1055,6 @@ static void imx_disable_dma(struct imx_port *sport) writel(temp, sport->port.membase + UCR4); sport->dma_is_enabled = 0; - port->low_latency = 0; } /* half the RX buffer size */ @@ -1303,6 +1276,16 @@ static void imx_shutdown(struct uart_port *port) clk_disable_unprepare(sport->clk_ipg); } +static void imx_flush_buffer(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + + if (sport->dma_is_enabled) { + sport->tx_bytes = 0; + dmaengine_terminate_all(sport->dma_chan_tx); + } +} + static void imx_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) @@ -1539,7 +1522,7 @@ imx_verify_port(struct uart_port *port, struct serial_struct *ser) ret = -EINVAL; if (sport->port.uartclk / 16 != ser->baud_base) ret = -EINVAL; - if ((void *)sport->port.mapbase != ser->iomem_base) + if (sport->port.mapbase != (unsigned long)ser->iomem_base) ret = -EINVAL; if (sport->port.iobase != ser->port) ret = -EINVAL; @@ -1623,6 +1606,7 @@ static struct uart_ops imx_pops = { .break_ctl = imx_break_ctl, .startup = imx_startup, .shutdown = imx_shutdown, + .flush_buffer = imx_flush_buffer, .set_termios = imx_set_termios, .type = imx_type, .release_port = imx_release_port, |