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authorLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 12:16:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-29 12:16:17 -0700
commit507ffe4f3840ac24890a8123c702cf1b7fe4d33c (patch)
tree1046888f9db00f268a0056d7f6e427e21502f84c /drivers/tty/serial/8250/8250_dma.c
parentfdc719b63ae35d6a2d8a2a2c76eed813294664bf (diff)
parent45efcb2d32d35f6509543e477568842d8467035d (diff)
Merge tag 'tty-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver update from Greg Kroah-Hartman: "Here's the big tty/serial driver merge request for 3.10-rc1 Once again, Jiri has a number of TTY driver fixes and cleanups, and Peter Hurley came through with a bunch of ldisc fixes that resolve a number of reported issues. There are some other serial driver cleanups as well. All of these have been in the linux-next tree for a while" * tag 'tty-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (117 commits) tty/serial/sirf: fix MODULE_DEVICE_TABLE serial: mxs: drop superfluous {get|put}_device serial: mxs: fix buffer overflow ARM: PL011: add support for extended FIFO-size of PL011-r1p5 serial_core.c: add put_device() after device_find_child() tty: Fix unsafe bit ops in tty_throttle_safe/unthrottle_safe serial: sccnxp: Replace pdata.init/exit with regulator API serial: sccnxp: Do not override device name TTY: pty, fix compilation warning TTY: rocket, fix compilation warning TTY: ircomm: fix DTR being raised on hang up TTY: synclinkmp: fix DTR being raised on hang up TTY: synclink_gt: fix DTR being raised on hang up TTY: synclink: fix DTR being raised on hang up serial: 8250_dw: Fix the stub for dw8250_probe_acpi() serial: 8250_dw: Convert to devm_ioremap() serial: 8250_dw: Set port capabilities based on CPR register serial: 8250_dw: Let ACPI code extract the DMA client info serial: 8250_dw: Support clk framework also with ACPI serial: 8250_dw: Enable runtime PM ...
Diffstat (limited to 'drivers/tty/serial/8250/8250_dma.c')
-rw-r--r--drivers/tty/serial/8250/8250_dma.c52
1 files changed, 34 insertions, 18 deletions
diff --git a/drivers/tty/serial/8250/8250_dma.c b/drivers/tty/serial/8250/8250_dma.c
index b9f7fd28112..7046769608d 100644
--- a/drivers/tty/serial/8250/8250_dma.c
+++ b/drivers/tty/serial/8250/8250_dma.c
@@ -33,10 +33,8 @@ static void __dma_tx_complete(void *param)
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&p->port);
- if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port)) {
+ if (!uart_circ_empty(xmit) && !uart_tx_stopped(&p->port))
serial8250_tx_dma(p);
- uart_write_wakeup(&p->port);
- }
}
static void __dma_rx_complete(void *param)
@@ -67,12 +65,11 @@ int serial8250_tx_dma(struct uart_8250_port *p)
struct circ_buf *xmit = &p->port.state->xmit;
struct dma_async_tx_descriptor *desc;
- if (dma->tx_running)
- return -EBUSY;
+ if (uart_tx_stopped(&p->port) || dma->tx_running ||
+ uart_circ_empty(xmit))
+ return 0;
dma->tx_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
- if (!dma->tx_size)
- return -EINVAL;
desc = dmaengine_prep_slave_single(dma->txchan,
dma->tx_addr + xmit->tail,
@@ -104,20 +101,29 @@ int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
struct dma_tx_state state;
int dma_status;
- /*
- * If RCVR FIFO trigger level was not reached, complete the transfer and
- * let 8250.c copy the remaining data.
- */
- if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT) {
- dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie,
- &state);
+ dma_status = dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state);
+
+ switch (iir & 0x3f) {
+ case UART_IIR_RLSI:
+ /* 8250_core handles errors and break interrupts */
+ return -EIO;
+ case UART_IIR_RX_TIMEOUT:
+ /*
+ * If RCVR FIFO trigger level was not reached, complete the
+ * transfer and let 8250_core copy the remaining data.
+ */
if (dma_status == DMA_IN_PROGRESS) {
dmaengine_pause(dma->rxchan);
__dma_rx_complete(p);
}
return -ETIMEDOUT;
+ default:
+ break;
}
+ if (dma_status)
+ return 0;
+
desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr,
dma->rx_size, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
@@ -143,21 +149,31 @@ int serial8250_request_dma(struct uart_8250_port *p)
struct uart_8250_dma *dma = p->dma;
dma_cap_mask_t mask;
- dma->rxconf.src_addr = p->port.mapbase + UART_RX;
- dma->txconf.dst_addr = p->port.mapbase + UART_TX;
+ /* Default slave configuration parameters */
+ dma->rxconf.direction = DMA_DEV_TO_MEM;
+ dma->rxconf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma->rxconf.src_addr = p->port.mapbase + UART_RX;
+
+ dma->txconf.direction = DMA_MEM_TO_DEV;
+ dma->txconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma->txconf.dst_addr = p->port.mapbase + UART_TX;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
/* Get a channel for RX */
- dma->rxchan = dma_request_channel(mask, dma->fn, dma->rx_param);
+ dma->rxchan = dma_request_slave_channel_compat(mask,
+ dma->fn, dma->rx_param,
+ p->port.dev, "rx");
if (!dma->rxchan)
return -ENODEV;
dmaengine_slave_config(dma->rxchan, &dma->rxconf);
/* Get a channel for TX */
- dma->txchan = dma_request_channel(mask, dma->fn, dma->tx_param);
+ dma->txchan = dma_request_slave_channel_compat(mask,
+ dma->fn, dma->tx_param,
+ p->port.dev, "tx");
if (!dma->txchan) {
dma_release_channel(dma->rxchan);
return -ENODEV;