diff options
author | John Stultz <john.stultz@linaro.org> | 2011-04-05 12:21:10 -0700 |
---|---|---|
committer | John Stultz <john.stultz@linaro.org> | 2011-04-05 12:21:10 -0700 |
commit | 4ce7ea0bfbb301ffb79154b6cecd2ef030db4cdf (patch) | |
tree | a7ad87580793912a9da208e7a9ea21d6c7768f08 /drivers/tty | |
parent | 4450182f400f1a5f50b1680faec25af2315c2849 (diff) | |
parent | 7c4bc9c2662c6d9840afed0e29eb01314af9bb78 (diff) |
Merge branch 'upstream/linaro.38' into linaro-android.38
Conflicts:
arch/arm/kernel/signal.c
drivers/mmc/card/block.c
drivers/mtd/nand/Kconfig
include/linux/amba/mmci.h
kernel/printk.c
mm/shmem.c
net/socket.c
Diffstat (limited to 'drivers/tty')
-rw-r--r-- | drivers/tty/serial/8250.c | 33 | ||||
-rw-r--r-- | drivers/tty/serial/amba-pl011.c | 511 | ||||
-rw-r--r-- | drivers/tty/serial/mrst_max3110.c | 2 | ||||
-rw-r--r-- | drivers/tty/serial/msm_serial.c | 286 | ||||
-rw-r--r-- | drivers/tty/serial/msm_serial.h | 28 | ||||
-rw-r--r-- | drivers/tty/serial/of_serial.c | 18 | ||||
-rw-r--r-- | drivers/tty/serial/omap-serial.c | 5 |
7 files changed, 754 insertions, 129 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index 3975df6f7fd..b3b881bc471 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -954,6 +954,23 @@ static int broken_efr(struct uart_8250_port *up) return 0; } +static inline int ns16550a_goto_highspeed(struct uart_8250_port *up) +{ + unsigned char status; + + status = serial_in(up, 0x04); /* EXCR2 */ +#define PRESL(x) ((x) & 0x30) + if (PRESL(status) == 0x10) { + /* already in high speed mode */ + return 0; + } else { + status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ + status |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ + serial_outp(up, 0x04, status); + } + return 1; +} + /* * We know that the chip has FIFOs. Does it have an EFR? The * EFR is located in the same register position as the IIR and @@ -1025,12 +1042,8 @@ static void autoconfig_16550a(struct uart_8250_port *up) quot = serial_dl_read(up); quot <<= 3; - status1 = serial_in(up, 0x04); /* EXCR2 */ - status1 &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ - status1 |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ - serial_outp(up, 0x04, status1); - - serial_dl_write(up, quot); + if (ns16550a_goto_highspeed(up)) + serial_dl_write(up, quot); serial_outp(up, UART_LCR, 0); @@ -3025,17 +3038,13 @@ void serial8250_resume_port(int line) struct uart_8250_port *up = &serial8250_ports[line]; if (up->capabilities & UART_NATSEMI) { - unsigned char tmp; - /* Ensure it's still in high speed mode */ serial_outp(up, UART_LCR, 0xE0); - tmp = serial_in(up, 0x04); /* EXCR2 */ - tmp &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ - tmp |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ - serial_outp(up, 0x04, tmp); + ns16550a_goto_highspeed(up); serial_outp(up, UART_LCR, 0); + up->port.uartclk = 921600*16; } uart_resume_port(&serial8250_reg, &up->port); } diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 0dae46f9102..57731e87008 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -96,6 +96,22 @@ static struct vendor_data vendor_st = { }; /* Deals with DMA transactions */ + +struct pl011_sgbuf { + struct scatterlist sg; + char *buf; +}; + +struct pl011_dmarx_data { + struct dma_chan *chan; + struct completion complete; + bool use_buf_b; + struct pl011_sgbuf sgbuf_a; + struct pl011_sgbuf sgbuf_b; + dma_cookie_t cookie; + bool running; +}; + struct pl011_dmatx_data { struct dma_chan *chan; struct scatterlist sg; @@ -120,12 +136,70 @@ struct uart_amba_port { char type[12]; #ifdef CONFIG_DMA_ENGINE /* DMA stuff */ - bool using_dma; + bool using_tx_dma; + bool using_rx_dma; + struct pl011_dmarx_data dmarx; struct pl011_dmatx_data dmatx; #endif }; /* + * Reads up to 256 characters from the FIFO or until it's empty and + * inserts them into the TTY layer. Returns the number of characters + * read from the FIFO. + */ +static int pl011_fifo_to_tty(struct uart_amba_port *uap) +{ + u16 status, ch; + unsigned int flag, max_count = 256; + int fifotaken = 0; + + while (max_count--) { + status = readw(uap->port.membase + UART01x_FR); + if (status & UART01x_FR_RXFE) + break; + + /* Take chars from the FIFO and update status */ + ch = readw(uap->port.membase + UART01x_DR) | + UART_DUMMY_DR_RX; + flag = TTY_NORMAL; + uap->port.icount.rx++; + fifotaken++; + + if (unlikely(ch & UART_DR_ERROR)) { + if (ch & UART011_DR_BE) { + ch &= ~(UART011_DR_FE | UART011_DR_PE); + uap->port.icount.brk++; + if (uart_handle_break(&uap->port)) + continue; + } else if (ch & UART011_DR_PE) + uap->port.icount.parity++; + else if (ch & UART011_DR_FE) + uap->port.icount.frame++; + if (ch & UART011_DR_OE) + uap->port.icount.overrun++; + + ch &= uap->port.read_status_mask; + + if (ch & UART011_DR_BE) + flag = TTY_BREAK; + else if (ch & UART011_DR_PE) + flag = TTY_PARITY; + else if (ch & UART011_DR_FE) + flag = TTY_FRAME; + } + + if (uart_handle_sysrq_char(&uap->port, ch & 255)) + continue; + + uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag); + } + + return fifotaken; +} + + +/* * All the DMA operation mode stuff goes inside this ifdef. * This assumes that you have a generic DMA device interface, * no custom DMA interfaces are supported. @@ -134,6 +208,31 @@ struct uart_amba_port { #define PL011_DMA_BUFFER_SIZE PAGE_SIZE +static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg, + enum dma_data_direction dir) +{ + sg->buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL); + if (!sg->buf) + return -ENOMEM; + + sg_init_one(&sg->sg, sg->buf, PL011_DMA_BUFFER_SIZE); + + if (dma_map_sg(chan->device->dev, &sg->sg, 1, dir) != 1) { + kfree(sg->buf); + return -EINVAL; + } + return 0; +} + +static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg, + enum dma_data_direction dir) +{ + if (sg->buf) { + dma_unmap_sg(chan->device->dev, &sg->sg, 1, dir); + kfree(sg->buf); + } +} + static void pl011_dma_probe_initcall(struct uart_amba_port *uap) { /* DMA is the sole user of the platform data right now */ @@ -153,7 +252,7 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap) return; } - /* Try to acquire a generic DMA engine slave channel */ + /* Try to acquire a generic DMA engine slave TX channel */ dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); @@ -168,6 +267,28 @@ static void pl011_dma_probe_initcall(struct uart_amba_port *uap) dev_info(uap->port.dev, "DMA channel TX %s\n", dma_chan_name(uap->dmatx.chan)); + + /* Optionally make use of an RX channel as well */ + if (plat->dma_rx_param) { + struct dma_slave_config rx_conf = { + .src_addr = uap->port.mapbase + UART01x_DR, + .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, + .direction = DMA_FROM_DEVICE, + .src_maxburst = uap->fifosize >> 1, + }; + + chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param); + if (!chan) { + dev_err(uap->port.dev, "no RX DMA channel!\n"); + return; + } + + dmaengine_slave_config(chan, &rx_conf); + uap->dmarx.chan = chan; + + dev_info(uap->port.dev, "DMA channel RX %s\n", + dma_chan_name(uap->dmarx.chan)); + } } #ifndef MODULE @@ -219,9 +340,10 @@ static void pl011_dma_remove(struct uart_amba_port *uap) /* TODO: remove the initcall if it has not yet executed */ if (uap->dmatx.chan) dma_release_channel(uap->dmatx.chan); + if (uap->dmarx.chan) + dma_release_channel(uap->dmarx.chan); } - /* Forward declare this for the refill routine */ static int pl011_dma_tx_refill(struct uart_amba_port *uap); @@ -380,7 +502,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap) */ static bool pl011_dma_tx_irq(struct uart_amba_port *uap) { - if (!uap->using_dma) + if (!uap->using_tx_dma) return false; /* @@ -432,7 +554,7 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) { u16 dmacr; - if (!uap->using_dma) + if (!uap->using_tx_dma) return false; if (!uap->port.x_char) { @@ -492,7 +614,7 @@ static void pl011_dma_flush_buffer(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; - if (!uap->using_dma) + if (!uap->using_tx_dma) return; /* Avoid deadlock with the DMA engine callback */ @@ -508,9 +630,219 @@ static void pl011_dma_flush_buffer(struct uart_port *port) } } +static void pl011_dma_rx_callback(void *data); + +static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) +{ + struct dma_chan *rxchan = uap->dmarx.chan; + struct dma_device *dma_dev; + struct pl011_dmarx_data *dmarx = &uap->dmarx; + struct dma_async_tx_descriptor *desc; + struct pl011_sgbuf *sgbuf; + + if (!rxchan) + return -EIO; + + /* Start the RX DMA job */ + sgbuf = uap->dmarx.use_buf_b ? + &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; + dma_dev = rxchan->device; + desc = rxchan->device->device_prep_slave_sg(rxchan, &sgbuf->sg, 1, + DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + /* + * If the DMA engine is busy and cannot prepare a + * channel, no big deal, the driver will fall back + * to interrupt mode as a result of this error code. + */ + if (!desc) { + uap->dmarx.running = false; + dmaengine_terminate_all(rxchan); + return -EBUSY; + } + + /* Some data to go along to the callback */ + desc->callback = pl011_dma_rx_callback; + desc->callback_param = uap; + dmarx->cookie = dmaengine_submit(desc); + dma_async_issue_pending(rxchan); + + uap->dmacr |= UART011_RXDMAE; + writew(uap->dmacr, uap->port.membase + UART011_DMACR); + uap->dmarx.running = true; + + uap->im &= ~UART011_RXIM; + writew(uap->im, uap->port.membase + UART011_IMSC); + + return 0; +} + +/* + * This is called when either the DMA job is complete, or + * the FIFO timeout interrupt occurred. This must be called + * with the port spinlock uap->port.lock held. + */ +static void pl011_dma_rx_chars(struct uart_amba_port *uap, + u32 pending, bool use_buf_b, + bool readfifo) +{ + struct tty_struct *tty = uap->port.state->port.tty; + struct pl011_sgbuf *sgbuf = use_buf_b ? + &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; + struct device *dev = uap->dmarx.chan->device->dev; + int dma_count = 0; + u32 fifotaken = 0; /* only used for vdbg() */ + + /* Pick everything from the DMA first */ + if (pending) { + /* Sync in buffer */ + dma_sync_sg_for_cpu(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE); + + /* + * First take all chars in the DMA pipe, then look in the FIFO. + * Note that tty_insert_flip_buf() tries to take as many chars + * as it can. + */ + dma_count = tty_insert_flip_string(uap->port.state->port.tty, + sgbuf->buf, pending); + + /* Return buffer to device */ + dma_sync_sg_for_device(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE); + + uap->port.icount.rx += dma_count; + if (dma_count < pending) + dev_warn(uap->port.dev, + "couldn't insert all characters (TTY is full?)\n"); + } + + /* + * Only continue with trying to read the FIFO if all DMA chars have + * been taken first. + */ + if (dma_count == pending && readfifo) { + /* Clear any error flags */ + writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS, + uap->port.membase + UART011_ICR); + + /* + * If we read all the DMA'd characters, and we had an + * incomplete buffer, that could be due to an rx error, or + * maybe we just timed out. Read any pending chars and check + * the error status. + * + * Error conditions will only occur in the FIFO, these will + * trigger an immediate interrupt and stop the DMA job, so we + * will always find the error in the FIFO, never in the DMA + * buffer. + */ + fifotaken = pl011_fifo_to_tty(uap); + } + + spin_unlock(&uap->port.lock); + dev_vdbg(uap->port.dev, + "Took %d chars from DMA buffer and %d chars from the FIFO\n", + dma_count, fifotaken); + tty_flip_buffer_push(tty); + spin_lock(&uap->port.lock); +} + +static void pl011_dma_rx_irq(struct uart_amba_port *uap) +{ + struct pl011_dmarx_data *dmarx = &uap->dmarx; + struct dma_chan *rxchan = dmarx->chan; + struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? + &dmarx->sgbuf_b : &dmarx->sgbuf_a; + size_t pending; + struct dma_tx_state state; + enum dma_status dmastat; + + /* + * Pause the transfer so we can trust the current counter, + * do this before we pause the PL011 block, else we may + * overflow the FIFO. + */ + if (dmaengine_pause(rxchan)) + dev_err(uap->port.dev, "unable to pause DMA transfer\n"); + dmastat = rxchan->device->device_tx_status(rxchan, + dmarx->cookie, &state); + if (dmastat != DMA_PAUSED) + dev_err(uap->port.dev, "unable to pause DMA transfer\n"); + + /* Disable RX DMA - incoming data will wait in the FIFO */ + uap->dmacr &= ~UART011_RXDMAE; + writew(uap->dmacr, uap->port.membase + UART011_DMACR); + uap->dmarx.running = false; + + pending = sgbuf->sg.length - state.residue; + BUG_ON(pending > PL011_DMA_BUFFER_SIZE); + /* Then we terminate the transfer - we now know our residue */ + dmaengine_terminate_all(rxchan); + + /* + * This will take the chars we have so far and insert + * into the framework. + */ + pl011_dma_rx_chars(uap, pending, dmarx->use_buf_b, true); + + /* Switch buffer & re-trigger DMA job */ + dmarx->use_buf_b = !dmarx->use_buf_b; + if (pl011_dma_rx_trigger_dma(uap)) { + dev_dbg(uap->port.dev, "could not retrigger RX DMA job " + "fall back to interrupt mode\n"); + uap->im |= UART011_RXIM; + writew(uap->im, uap->port.membase + UART011_IMSC); + } +} + +static void pl011_dma_rx_callback(void *data) +{ + struct uart_amba_port *uap = data; + struct pl011_dmarx_data *dmarx = &uap->dmarx; + bool lastbuf = dmarx->use_buf_b; + int ret; + + /* + * This completion interrupt occurs typically when the + * RX buffer is totally stuffed but no timeout has yet + * occurred. When that happens, we just want the RX + * routine to flush out the secondary DMA buffer while + * we immediately trigger the next DMA job. + */ + spin_lock_irq(&uap->port.lock); + uap->dmarx.running = false; + dmarx->use_buf_b = !lastbuf; + ret = pl011_dma_rx_trigger_dma(uap); + + pl011_dma_rx_chars(uap, PL011_DMA_BUFFER_SIZE, lastbuf, false); + spin_unlock_irq(&uap->port.lock); + /* + * Do this check after we picked the DMA chars so we don't + * get some IRQ immediately from RX. + */ + if (ret) { + dev_dbg(uap->port.dev, "could not retrigger RX DMA job " + "fall back to interrupt mode\n"); + uap->im |= UART011_RXIM; + writew(uap->im, uap->port.membase + UART011_IMSC); + } +} + +/* + * Stop accepting received characters, when we're shutting down or + * suspending this port. + * Locking: called with port lock held and IRQs disabled. + */ +static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) +{ + /* FIXME. Just disable the DMA enable */ + uap->dmacr &= ~UART011_RXDMAE; + writew(uap->dmacr, uap->port.membase + UART011_DMACR); +} static void pl011_dma_startup(struct uart_amba_port *uap) { + int ret; + if (!uap->dmatx.chan) return; @@ -525,8 +857,33 @@ static void pl011_dma_startup(struct uart_amba_port *uap) /* The DMA buffer is now the FIFO the TTY subsystem can use */ uap->port.fifosize = PL011_DMA_BUFFER_SIZE; - uap->using_dma = true; + uap->using_tx_dma = true; + + if (!uap->dmarx.chan) + goto skip_rx; + + /* Allocate and map DMA RX buffers */ + ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_a, + DMA_FROM_DEVICE); + if (ret) { + dev_err(uap->port.dev, "failed to init DMA %s: %d\n", + "RX buffer A", ret); + goto skip_rx; + } + + ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_b, + DMA_FROM_DEVICE); + if (ret) { + dev_err(uap->port.dev, "failed to init DMA %s: %d\n", + "RX buffer B", ret); + pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, + DMA_FROM_DEVICE); + goto skip_rx; + } + uap->using_rx_dma = true; + +skip_rx: /* Turn on DMA error (RX/TX will be enabled on demand) */ uap->dmacr |= UART011_DMAONERR; writew(uap->dmacr, uap->port.membase + UART011_DMACR); @@ -539,11 +896,17 @@ static void pl011_dma_startup(struct uart_amba_port *uap) if (uap->vendor->dma_threshold) writew(ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16, uap->port.membase + ST_UART011_DMAWM); + + if (uap->using_rx_dma) { + if (pl011_dma_rx_trigger_dma(uap)) + dev_dbg(uap->port.dev, "could not trigger initial " + "RX DMA job, fall back to interrupt mode\n"); + } } static void pl011_dma_shutdown(struct uart_amba_port *uap) { - if (!uap->using_dma) + if (!(uap->using_tx_dma || uap->using_rx_dma)) return; /* Disable RX and TX DMA */ @@ -555,19 +918,39 @@ static void pl011_dma_shutdown(struct uart_amba_port *uap) writew(uap->dmacr, uap->port.membase + UART011_DMACR); spin_unlock_irq(&uap->port.lock); - /* In theory, this should already be done by pl011_dma_flush_buffer */ - dmaengine_terminate_all(uap->dmatx.chan); - if (uap->dmatx.queued) { - dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, - DMA_TO_DEVICE); - uap->dmatx.queued = false; + if (uap->using_tx_dma) { + /* In theory, this should already be done by pl011_dma_flush_buffer */ + dmaengine_terminate_all(uap->dmatx.chan); + if (uap->dmatx.queued) { + dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, + DMA_TO_DEVICE); + uap->dmatx.queued = false; + } + + kfree(uap->dmatx.buf); + uap->using_tx_dma = false; } - kfree(uap->dmatx.buf); + if (uap->using_rx_dma) { + dmaengine_terminate_all(uap->dmarx.chan); + /* Clean up the RX DMA */ + pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, DMA_FROM_DEVICE); + pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_b, DMA_FROM_DEVICE); + uap->using_rx_dma = false; + } +} - uap->using_dma = false; +static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) +{ + return uap->using_rx_dma; } +static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) +{ + return uap->using_rx_dma && uap->dmarx.running; +} + + #else /* Blank functions if the DMA engine is not available */ static inline void pl011_dma_probe(struct uart_amba_port *uap) @@ -600,6 +983,29 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) return false; } +static inline void pl011_dma_rx_irq(struct uart_amba_port *uap) +{ +} + +static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) +{ +} + +static inline int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) +{ + return -EIO; +} + +static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) +{ + return false; +} + +static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) +{ + return false; +} + #define pl011_dma_flush_buffer NULL #endif @@ -630,6 +1036,8 @@ static void pl011_stop_rx(struct uart_port *port) uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM| UART011_PEIM|UART011_BEIM|UART011_OEIM); writew(uap->im, uap->port.membase + UART011_IMSC); + + pl011_dma_rx_stop(uap); } static void pl011_enable_ms(struct uart_port *port) @@ -643,51 +1051,24 @@ static void pl011_enable_ms(struct uart_port *port) static void pl011_rx_chars(struct uart_amba_port *uap) { struct tty_struct *tty = uap->port.state->port.tty; - unsigned int status, ch, flag, max_count = 256; - - status = readw(uap->port.membase + UART01x_FR); - while ((status & UART01x_FR_RXFE) == 0 && max_count--) { - ch = readw(uap->port.membase + UART01x_DR) | UART_DUMMY_DR_RX; - flag = TTY_NORMAL; - uap->port.icount.rx++; - - /* - * Note that the error handling code is - * out of the main execution path - */ - if (unlikely(ch & UART_DR_ERROR)) { - if (ch & UART011_DR_BE) { - ch &= ~(UART011_DR_FE | UART011_DR_PE); - uap->port.icount.brk++; - if (uart_handle_break(&uap->port)) - goto ignore_char; - } else if (ch & UART011_DR_PE) - uap->port.icount.parity++; - else if (ch & UART011_DR_FE) - uap->port.icount.frame++; - if (ch & UART011_DR_OE) - uap->port.icount.overrun++; - - ch &= uap->port.read_status_mask; - - if (ch & UART011_DR_BE) - flag = TTY_BREAK; - else if (ch & UART011_DR_PE) - flag = TTY_PARITY; - else if (ch & UART011_DR_FE) - flag = TTY_FRAME; - } - if (uart_handle_sysrq_char(&uap->port, ch & 255)) - goto ignore_char; - - uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag); + pl011_fifo_to_tty(uap); - ignore_char: - status = readw(uap->port.membase + UART01x_FR); - } spin_unlock(&uap->port.lock); tty_flip_buffer_push(tty); + /* + * If we were temporarily out of DMA mode for a while, + * attempt to switch back to DMA mode again. + */ + if (pl011_dma_rx_available(uap)) { + if (pl011_dma_rx_trigger_dma(uap)) { + dev_dbg(uap->port.dev, "could not trigger RX DMA job " + "fall back to interrupt mode again\n"); + uap->im |= UART011_RXIM; + } else + uap->im &= ~UART011_RXIM; + writew(uap->im, uap->port.membase + UART011_IMSC); + } spin_lock(&uap->port.lock); } @@ -767,8 +1148,12 @@ static irqreturn_t pl011_int(int irq, void *dev_id) UART011_RXIS), uap->port.membase + UART011_ICR); - if (status & (UART011_RTIS|UART011_RXIS)) - pl011_rx_chars(uap); + if (status & (UART011_RTIS|UART011_RXIS)) { + if (pl011_dma_rx_running(uap)) + pl011_dma_rx_irq(uap); + else + pl011_rx_chars(uap); + } if (status & (UART011_DSRMIS|UART011_DCDMIS| UART011_CTSMIS|UART011_RIMIS)) pl011_modem_status(uap); @@ -945,10 +1330,14 @@ static int pl011_startup(struct uart_port *port) pl011_dma_startup(uap); /* - * Finally, enable interrupts + * Finally, enable interrupts, only timeouts when using DMA + * if initial RX DMA job failed, start in interrupt mode + * as well. */ spin_lock_irq(&uap->port.lock); - uap->im = UART011_RXIM | UART011_RTIM; + uap->im = UART011_RTIM; + if (!pl011_dma_rx_running(uap)) + uap->im |= UART011_RXIM; writew(uap->im, uap->port.membase + UART011_IMSC); spin_unlock_irq(&uap->port.lock); diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c index b62857bf2fd..37e13c3d91d 100644 --- a/drivers/tty/serial/mrst_max3110.c +++ b/drivers/tty/serial/mrst_max3110.c @@ -51,7 +51,7 @@ struct uart_max3110 { struct uart_port port; struct spi_device *spi; - char name[24]; + char name[SPI_NAME_SIZE]; wait_queue_head_t wq; struct task_struct *main_thread; diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c index 8e43a7b69e6..bfee9b4c666 100644 --- a/drivers/tty/serial/msm_serial.c +++ b/drivers/tty/serial/msm_serial.c @@ -3,6 +3,7 @@ * * Copyright (C) 2007 Google, Inc. * Author: Robert Love <rlove@google.com> + * Copyright (c) 2011, Code Aurora Forum. All rights reserved. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and @@ -31,6 +32,7 @@ #include <linux/serial.h> #include <linux/clk.h> #include <linux/platform_device.h> +#include <linux/delay.h> #include "msm_serial.h" @@ -38,9 +40,20 @@ struct msm_port { struct uart_port uart; char name[16]; struct clk *clk; + struct clk *pclk; unsigned int imr; + unsigned int *gsbi_base; + int is_uartdm; + unsigned int old_snap_state; }; +static inline void wait_for_xmitr(struct uart_port *port, int bits) +{ + if (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) + while ((msm_read(port, UART_ISR) & bits) != bits) + cpu_relax(); +} + static void msm_stop_tx(struct uart_port *port) { struct msm_port *msm_port = UART_TO_MSM(port); @@ -73,6 +86,61 @@ static void msm_enable_ms(struct uart_port *port) msm_write(port, msm_port->imr, UART_IMR); } +static void handle_rx_dm(struct uart_port *port, unsigned int misr) +{ + struct tty_struct *tty = port->state->port.tty; + unsigned int sr; + int count = 0; + struct msm_port *msm_port = UART_TO_MSM(port); + + if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) { + port->icount.overrun++; + tty_insert_flip_char(tty, 0, TTY_OVERRUN); + msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR); + } + + if (misr & UART_IMR_RXSTALE) { + count = msm_read(port, UARTDM_RX_TOTAL_SNAP) - + msm_port->old_snap_state; + msm_port->old_snap_state = 0; + } else { + count = 4 * (msm_read(port, UART_RFWR)); + msm_port->old_snap_state += count; + } + + /* TODO: Precise error reporting */ + + port->icount.rx += count; + + while (count > 0) { + unsigned int c; + + sr = msm_read(port, UART_SR); + if ((sr & UART_SR_RX_READY) == 0) { + msm_port->old_snap_state -= count; + break; + } + c = msm_read(port, UARTDM_RF); + if (sr & UART_SR_RX_BREAK) { + port->icount.brk++; + if (uart_handle_break(port)) + continue; + } else if (sr & UART_SR_PAR_FRAME_ERR) + port->icount.frame++; + + /* TODO: handle sysrq */ + tty_insert_flip_string(tty, (char *) &c, + (count > 4) ? 4 : count); + count -= 4; + } + + tty_flip_buffer_push(tty); + if (misr & (UART_IMR_RXSTALE)) + msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR); + msm_write(port, 0xFFFFFF, UARTDM_DMRX); + msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR); +} + static void handle_rx(struct uart_port *port) { struct tty_struct *tty = port->state->port.tty; @@ -121,6 +189,12 @@ static void handle_rx(struct uart_port *port) tty_flip_buffer_push(tty); } +static void reset_dm_count(struct uart_port *port) +{ + wait_for_xmitr(port, UART_ISR_TX_READY); + msm_write(port, 1, UARTDM_NCF_TX); +} + static void handle_tx(struct uart_port *port) { struct circ_buf *xmit = &port->state->xmit; @@ -128,11 +202,18 @@ static void handle_tx(struct uart_port *port) int sent_tx; if (port->x_char) { - msm_write(port, port->x_char, UART_TF); + if (msm_port->is_uartdm) + reset_dm_count(port); + + msm_write(port, port->x_char, + msm_port->is_uartdm ? UARTDM_TF : UART_TF); port->icount.tx++; port->x_char = 0; } + if (msm_port->is_uartdm) + reset_dm_count(port); + while (msm_read(port, UART_SR) & UART_SR_TX_READY) { if (uart_circ_empty(xmit)) { /* disable tx interrupts */ @@ -140,8 +221,11 @@ static void handle_tx(struct uart_port *port) msm_write(port, msm_port->imr, UART_IMR); break; } + msm_write(port, xmit->buf[xmit->tail], + msm_port->is_uartdm ? UARTDM_TF : UART_TF); - msm_write(port, xmit->buf[xmit->tail], UART_TF); + if (msm_port->is_uartdm) + reset_dm_count(port); xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); port->icount.tx++; @@ -169,8 +253,12 @@ static irqreturn_t msm_irq(int irq, void *dev_id) misr = msm_read(port, UART_MISR); msm_write(port, 0, UART_IMR); /* disable interrupt */ - if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) - handle_rx(port); + if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) { + if (msm_port->is_uartdm) + handle_rx_dm(port, misr); + else + handle_rx(port); + } if (misr & UART_IMR_TXLEV) handle_tx(port); if (misr & UART_IMR_DELTA_CTS) @@ -192,10 +280,21 @@ static unsigned int msm_get_mctrl(struct uart_port *port) return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS; } -static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl) + +static void msm_reset(struct uart_port *port) { - unsigned int mr; + /* reset everything */ + msm_write(port, UART_CR_CMD_RESET_RX, UART_CR); + msm_write(port, UART_CR_CMD_RESET_TX, UART_CR); + msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR); + msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR); + msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR); + msm_write(port, UART_CR_CMD_SET_RFR, UART_CR); +} +void msm_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + unsigned int mr; mr = msm_read(port, UART_MR1); if (!(mctrl & TIOCM_RTS)) { @@ -219,6 +318,7 @@ static void msm_break_ctl(struct uart_port *port, int break_ctl) static int msm_set_baud_rate(struct uart_port *port, unsigned int baud) { unsigned int baud_code, rxstale, watermark; + struct msm_port *msm_port = UART_TO_MSM(port); switch (baud) { case 300: @@ -273,6 +373,9 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud) break; } + if (msm_port->is_uartdm) + msm_write(port, UART_CR_CMD_RESET_RX, UART_CR); + msm_write(port, baud_code, UART_CSR); /* RX stale watermark */ @@ -288,25 +391,23 @@ static int msm_set_baud_rate(struct uart_port *port, unsigned int baud) /* set TX watermark */ msm_write(port, 10, UART_TFWR); + if (msm_port->is_uartdm) { + msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR); + msm_write(port, 0xFFFFFF, UARTDM_DMRX); + msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR); + } + return baud; } -static void msm_reset(struct uart_port *port) -{ - /* reset everything */ - msm_write(port, UART_CR_CMD_RESET_RX, UART_CR); - msm_write(port, UART_CR_CMD_RESET_TX, UART_CR); - msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR); - msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR); - msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR); - msm_write(port, UART_CR_CMD_SET_RFR, UART_CR); -} static void msm_init_clock(struct uart_port *port) { struct msm_port *msm_port = UART_TO_MSM(port); clk_enable(msm_port->clk); + if (!IS_ERR(msm_port->pclk)) + clk_enable(msm_port->pclk); msm_serial_set_mnd_regs(port); } @@ -347,15 +448,31 @@ static int msm_startup(struct uart_port *port) msm_write(port, data, UART_IPR); } - msm_reset(port); + data = 0; + if (!port->cons || (port->cons && !(port->cons->flags & CON_ENABLED))) { + msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR); + msm_reset(port); + data = UART_CR_TX_ENABLE; + } + + data |= UART_CR_RX_ENABLE; + msm_write(port, data, UART_CR); /* enable TX & RX */ - msm_write(port, 0x05, UART_CR); /* enable TX & RX */ + /* Make sure IPR is not 0 to start with*/ + if (msm_port->is_uartdm) + msm_write(port, UART_IPR_STALE_LSB, UART_IPR); /* turn on RX and CTS interrupts */ msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE | UART_IMR_CURRENT_CTS; - msm_write(port, msm_port->imr, UART_IMR); + if (msm_port->is_uartdm) { + msm_write(port, 0xFFFFFF, UARTDM_DMRX); + msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR); + msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR); + } + + msm_write(port, msm_port->imr, UART_IMR); return 0; } @@ -384,7 +501,7 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios, baud = msm_set_baud_rate(port, baud); if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, baud, baud); - + /* calculate parity */ mr = msm_read(port, UART_MR2); mr &= ~UART_MR2_PARITY_MODE; @@ -454,48 +571,105 @@ static const char *msm_type(struct uart_port *port) static void msm_release_port(struct uart_port *port) { struct platform_device *pdev = to_platform_device(port->dev); - struct resource *resource; + struct msm_port *msm_port = UART_TO_MSM(port); + struct resource *uart_resource; + struct resource *gsbi_resource; resource_size_t size; - resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (unlikely(!resource)) + uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (unlikely(!uart_resource)) return; - size = resource->end - resource->start + 1; + size = resource_size(uart_resource); release_mem_region(port->mapbase, size); iounmap(port->membase); port->membase = NULL; + + if (msm_port->gsbi_base) { + iowrite32(GSBI_PROTOCOL_IDLE, msm_port->gsbi_base + + GSBI_CONTROL); + + gsbi_resource = platform_get_resource_byname(pdev, + IORESOURCE_MEM, + "gsbi_resource"); + + if (unlikely(!gsbi_resource)) + return; + + size = resource_size(gsbi_resource); + release_mem_region(gsbi_resource->start, size); + iounmap(msm_port->gsbi_base); + msm_port->gsbi_base = NULL; + } } static int msm_request_port(struct uart_port *port) { + struct msm_port *msm_port = UART_TO_MSM(port); struct platform_device *pdev = to_platform_device(port->dev); - struct resource *resource; + struct resource *uart_resource; + struct resource *gsbi_resource; resource_size_t size; + int ret; - resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (unlikely(!resource)) + uart_resource = platform_get_resource_byname(pdev, IORESOURCE_MEM, + "uart_resource"); + if (unlikely(!uart_resource)) return -ENXIO; - size = resource->end - resource->start + 1; - if (unlikely(!request_mem_region(port->mapbase, size, "msm_serial"))) + size = resource_size(uart_resource); + + if (!request_mem_region(port->mapbase, size, "msm_serial")) return -EBUSY; port->membase = ioremap(port->mapbase, size); if (!port->membase) { - release_mem_region(port->mapbase, size); - return -EBUSY; + ret = -EBUSY; + goto fail_release_port; + } + + gsbi_resource = platform_get_resource_byname(pdev, IORESOURCE_MEM, + "gsbi_resource"); + /* Is this a GSBI-based port? */ + if (gsbi_resource) { + size = resource_size(gsbi_resource); + + if (!request_mem_region(gsbi_resource->start, size, + "msm_serial")) { + ret = -EBUSY; + goto fail_release_port; + } + + msm_port->gsbi_base = ioremap(gsbi_resource->start, size); + if (!msm_port->gsbi_base) { + ret = -EBUSY; + goto fail_release_gsbi; + } } return 0; + +fail_release_gsbi: + release_mem_region(gsbi_resource->start, size); +fail_release_port: + release_mem_region(port->mapbase, size); + return ret; } static void msm_config_port(struct uart_port *port, int flags) { + struct msm_port *msm_port = UART_TO_MSM(port); + int ret; if (flags & UART_CONFIG_TYPE) { port->type = PORT_MSM; - msm_request_port(port); + ret = msm_request_port(port); + if (ret) + return; } + + if (msm_port->is_uartdm) + iowrite32(GSBI_PROTOCOL_UART, msm_port->gsbi_base + + GSBI_CONTROL); } static int msm_verify_port(struct uart_port *port, struct serial_struct *ser) @@ -515,9 +689,13 @@ static void msm_power(struct uart_port *port, unsigned int state, switch (state) { case 0: clk_enable(msm_port->clk); + if (!IS_ERR(msm_port->pclk)) + clk_enable(msm_port->pclk); break; case 3: clk_disable(msm_port->clk); + if (!IS_ERR(msm_port->pclk)) + clk_disable(msm_port->pclk); break; default: printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state); @@ -550,7 +728,7 @@ static struct msm_port msm_uart_ports[] = { .iotype = UPIO_MEM, .ops = &msm_uart_pops, .flags = UPF_BOOT_AUTOCONF, - .fifosize = 512, + .fifosize = 64, .line = 0, }, }, @@ -559,7 +737,7 @@ static struct msm_port msm_uart_ports[] = { .iotype = UPIO_MEM, .ops = &msm_uart_pops, .flags = UPF_BOOT_AUTOCONF, - .fifosize = 512, + .fifosize = 64, .line = 1, }, }, @@ -585,9 +763,14 @@ static inline struct uart_port *get_port_from_line(unsigned int line) static void msm_console_putchar(struct uart_port *port, int c) { + struct msm_port *msm_port = UART_TO_MSM(port); + + if (msm_port->is_uartdm) + reset_dm_count(port); + while (!(msm_read(port, UART_SR) & UART_SR_TX_READY)) ; - msm_write(port, c, UART_TF); + msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF); } static void msm_console_write(struct console *co, const char *s, @@ -609,12 +792,14 @@ static void msm_console_write(struct console *co, const char *s, static int __init msm_console_setup(struct console *co, char *options) { struct uart_port *port; + struct msm_port *msm_port; int baud, flow, bits, parity; if (unlikely(co->index >= UART_NR || co->index < 0)) return -ENXIO; port = get_port_from_line(co->index); + msm_port = UART_TO_MSM(port); if (unlikely(!port->membase)) return -ENXIO; @@ -638,6 +823,11 @@ static int __init msm_console_setup(struct console *co, char *options) msm_reset(port); + if (msm_port->is_uartdm) { + msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR); + msm_write(port, UART_CR_TX_ENABLE, UART_CR); + } + printk(KERN_INFO "msm_serial: console setup on port #%d\n", port->line); return uart_set_options(port, co, baud, parity, bits, flow); @@ -685,14 +875,32 @@ static int __init msm_serial_probe(struct platform_device *pdev) port->dev = &pdev->dev; msm_port = UART_TO_MSM(port); - msm_port->clk = clk_get(&pdev->dev, "uart_clk"); - if (IS_ERR(msm_port->clk)) - return PTR_ERR(msm_port->clk); + if (platform_get_resource_byname(pdev, IORESOURCE_MEM, "gsbi_resource")) + msm_port->is_uartdm = 1; + else + msm_port->is_uartdm = 0; + + if (msm_port->is_uartdm) { + msm_port->clk = clk_get(&pdev->dev, "gsbi_uart_clk"); + msm_port->pclk = clk_get(&pdev->dev, "gsbi_pclk"); + } else { + msm_port->clk = clk_get(&pdev->dev, "uart_clk"); + msm_port->pclk = ERR_PTR(-ENOENT); + } + + if (unlikely(IS_ERR(msm_port->clk) || (IS_ERR(msm_port->pclk) && + msm_port->is_uartdm))) + return PTR_ERR(msm_port->clk); + + if (msm_port->is_uartdm) + clk_set_rate(msm_port->clk, 7372800); + port->uartclk = clk_get_rate(msm_port->clk); printk(KERN_INFO "uartclk = %d\n", port->uartclk); - resource = platform_get_resource(pdev, IORESOURCE_MEM, 0); + resource = platform_get_resource_byname(pdev, IORESOURCE_MEM, + "uart_resource"); if (unlikely(!resource)) return -ENXIO; port->mapbase = resource->start; diff --git a/drivers/tty/serial/msm_serial.h b/drivers/tty/serial/msm_serial.h index f6ca9ca79e9..9b8dc5d0d85 100644 --- a/drivers/tty/serial/msm_serial.h +++ b/drivers/tty/serial/msm_serial.h @@ -3,6 +3,7 @@ * * Copyright (C) 2007 Google, Inc. * Author: Robert Love <rlove@google.com> + * Copyright (c) 2011, Code Aurora Forum. All rights reserved. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and @@ -54,6 +55,7 @@ #define UART_CSR_300 0x22 #define UART_TF 0x000C +#define UARTDM_TF 0x0070 #define UART_CR 0x0010 #define UART_CR_CMD_NULL (0 << 4) @@ -64,14 +66,17 @@ #define UART_CR_CMD_START_BREAK (5 << 4) #define UART_CR_CMD_STOP_BREAK (6 << 4) #define UART_CR_CMD_RESET_CTS (7 << 4) +#define UART_CR_CMD_RESET_STALE_INT (8 << 4) #define UART_CR_CMD_PACKET_MODE (9 << 4) #define UART_CR_CMD_MODE_RESET (12 << 4) #define UART_CR_CMD_SET_RFR (13 << 4) #define UART_CR_CMD_RESET_RFR (14 << 4) +#define UART_CR_CMD_PROTECTION_EN (16 << 4) +#define UART_CR_CMD_STALE_EVENT_ENABLE (80 << 4) #define UART_CR_TX_DISABLE (1 << 3) -#define UART_CR_TX_ENABLE (1 << 3) -#define UART_CR_RX_DISABLE (1 << 3) -#define UART_CR_RX_ENABLE (1 << 3) +#define UART_CR_TX_ENABLE (1 << 2) +#define UART_CR_RX_DISABLE (1 << 1) +#define UART_CR_RX_ENABLE (1 << 0) #define UART_IMR 0x0014 #define UART_IMR_TXLEV (1 << 0) @@ -110,9 +115,20 @@ #define UART_SR_RX_FULL (1 << 1) #define UART_SR_RX_READY (1 << 0) -#define UART_RF 0x000C -#define UART_MISR 0x0010 -#define UART_ISR 0x0014 +#define UART_RF 0x000C +#define UARTDM_RF 0x0070 +#define UART_MISR 0x0010 +#define UART_ISR 0x0014 +#define UART_ISR_TX_READY (1 << 7) + +#define GSBI_CONTROL 0x0 +#define GSBI_PROTOCOL_CODE 0x30 +#define GSBI_PROTOCOL_UART 0x40 +#define GSBI_PROTOCOL_IDLE 0x0 + +#define UARTDM_DMRX 0x34 +#define UARTDM_NCF_TX 0x40 +#define UARTDM_RX_TOTAL_SNAP 0x38 #define UART_TO_MSM(uart_port) ((struct msm_port *) uart_port) diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 5c7abe4c94d..6a18ca6ddaa 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -160,17 +160,17 @@ static int of_platform_serial_remove(struct platform_device *ofdev) * A few common types, add more as needed. */ static struct of_device_id __devinitdata of_platform_serial_table[] = { - { .type = "serial", .compatible = "ns8250", .data = (void *)PORT_8250, }, - { .type = "serial", .compatible = "ns16450", .data = (void *)PORT_16450, }, - { .type = "serial", .compatible = "ns16550a", .data = (void *)PORT_16550A, }, - { .type = "serial", .compatible = "ns16550", .data = (void *)PORT_16550, }, - { .type = "serial", .compatible = "ns16750", .data = (void *)PORT_16750, }, - { .type = "serial", .compatible = "ns16850", .data = (void *)PORT_16850, }, + { .compatible = "ns8250", .data = (void *)PORT_8250, }, + { .compatible = "ns16450", .data = (void *)PORT_16450, }, + { .compatible = "ns16550a", .data = (void *)PORT_16550A, }, + { .compatible = "ns16550", .data = (void *)PORT_16550, }, + { .compatible = "ns16750", .data = (void *)PORT_16750, }, + { .compatible = "ns16850", .data = (void *)PORT_16850, }, #ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL - { .type = "serial", .compatible = "ibm,qpace-nwp-serial", - .data = (void *)PORT_NWPSERIAL, }, + { .compatible = "ibm,qpace-nwp-serial", + .data = (void *)PORT_NWPSERIAL, }, #endif - { .type = "serial", .data = (void *)PORT_UNKNOWN, }, + { .type = "serial", .data = (void *)PORT_UNKNOWN, }, { /* end of list */ }, }; diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index 7f2f0105878..699b34446a5 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -20,6 +20,10 @@ * this driver as required for the omap-platform. */ +#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + #include <linux/module.h> #include <linux/init.h> #include <linux/console.h> @@ -190,7 +194,6 @@ static inline void receive_chars(struct uart_omap_port *up, int *status) if (up->port.line == up->port.cons->index) { /* Recover the break flag from console xmit */ lsr |= up->lsr_break_flag; - up->lsr_break_flag = 0; } #endif if (lsr & UART_LSR_BI) |