diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_omap.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_omap.c | 49 |
1 files changed, 33 insertions, 16 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 66901d93089a3c..170639d12b2a0f 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -19,7 +19,6 @@ #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/of.h> -#include <linux/of_gpio.h> #include <linux/of_irq.h> #include <linux/delay.h> #include <linux/pm_runtime.h> @@ -1094,7 +1093,7 @@ static void omap_8250_dma_tx_complete(void *param) { struct uart_8250_port *p = param; struct uart_8250_dma *dma = p->dma; - struct circ_buf *xmit = &p->port.state->xmit; + struct tty_port *tport = &p->port.state->port; unsigned long flags; bool en_thri = false; struct omap8250_priv *priv = p->port.private_data; @@ -1113,10 +1112,10 @@ static void omap_8250_dma_tx_complete(void *param) omap8250_restore_regs(p); } - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS) uart_write_wakeup(&p->port); - if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) { + if (!kfifo_is_empty(&tport->xmit_fifo) && !uart_tx_stopped(&p->port)) { int ret; ret = omap_8250_tx_dma(p); @@ -1138,14 +1137,15 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) { struct uart_8250_dma *dma = p->dma; struct omap8250_priv *priv = p->port.private_data; - struct circ_buf *xmit = &p->port.state->xmit; + struct tty_port *tport = &p->port.state->port; struct dma_async_tx_descriptor *desc; - unsigned int skip_byte = 0; + struct scatterlist sg; + int skip_byte = -1; int ret; if (dma->tx_running) return 0; - if (uart_tx_stopped(&p->port) || uart_circ_empty(xmit)) { + if (uart_tx_stopped(&p->port) || kfifo_is_empty(&tport->xmit_fifo)) { /* * Even if no data, we need to return an error for the two cases @@ -1160,8 +1160,18 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) return 0; } - dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); + sg_init_table(&sg, 1); + ret = kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, + UART_XMIT_SIZE, dma->tx_addr); + if (ret != 1) { + serial8250_clear_THRI(p); + return 0; + } + + dma->tx_size = sg_dma_len(&sg); + if (priv->habit & OMAP_DMA_TX_KICK) { + unsigned char c; u8 tx_lvl; /* @@ -1188,12 +1198,17 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) ret = -EINVAL; goto err; } - skip_byte = 1; + if (!kfifo_get(&tport->xmit_fifo, &c)) { + ret = -EINVAL; + goto err; + } + skip_byte = c; + /* now we need to recompute due to kfifo_get */ + kfifo_dma_out_prepare_mapped(&tport->xmit_fifo, &sg, 1, + UART_XMIT_SIZE, dma->tx_addr); } - desc = dmaengine_prep_slave_single(dma->txchan, - dma->tx_addr + xmit->tail + skip_byte, - dma->tx_size - skip_byte, DMA_MEM_TO_DEV, + desc = dmaengine_prep_slave_sg(dma->txchan, &sg, 1, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) { ret = -EBUSY; @@ -1215,11 +1230,13 @@ static int omap_8250_tx_dma(struct uart_8250_port *p) dma->tx_err = 0; serial8250_clear_THRI(p); - if (skip_byte) - serial_out(p, UART_TX, xmit->buf[xmit->tail]); - return 0; + ret = 0; + goto out_skip; err: dma->tx_err = 1; +out_skip: + if (skip_byte >= 0) + serial_out(p, UART_TX, skip_byte); return ret; } @@ -1308,7 +1325,7 @@ static int omap_8250_dma_handle_irq(struct uart_port *port) serial8250_modem_status(up); if (status & UART_LSR_THRE && up->dma->tx_err) { if (uart_tx_stopped(&up->port) || - uart_circ_empty(&up->port.state->xmit)) { + kfifo_is_empty(&up->port.state->port.xmit_fifo)) { up->dma->tx_err = 0; serial8250_tx_chars(up); } else { |