struct circ_buf rx_ring;
- struct serial_rs485 rs485; /* rs485 settings */
struct mctrl_gpios *gpios;
int gpio_irq[UART_GPIO_MAX];
unsigned int tx_done_mask;
}
/* Enable or disable the rs485 support */
-void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
+static int atmel_config_rs485(struct uart_port *port,
+ struct serial_rs485 *rs485conf)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int mode;
- unsigned long flags;
-
- spin_lock_irqsave(&port->lock, flags);
/* Disable interrupts */
UART_PUT_IDR(port, atmel_port->tx_done_mask);
/* Resetting serial mode to RS232 (0x0) */
mode &= ~ATMEL_US_USMODE;
- atmel_port->rs485 = *rs485conf;
+ port->rs485 = *rs485conf;
if (rs485conf->flags & SER_RS485_ENABLED) {
dev_dbg(port->dev, "Setting UART to RS485\n");
/* Enable interrupts */
UART_PUT_IER(port, atmel_port->tx_done_mask);
- spin_unlock_irqrestore(&port->lock, flags);
-
+ return 0;
}
/*
/* Resetting serial mode to RS232 (0x0) */
mode &= ~ATMEL_US_USMODE;
- if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
+ if (port->rs485.flags & SER_RS485_ENABLED) {
dev_dbg(port->dev, "Setting UART to RS485\n");
- if ((atmel_port->rs485.delay_rts_after_send) > 0)
- UART_PUT_TTGR(port,
- atmel_port->rs485.delay_rts_after_send);
+ if ((port->rs485.delay_rts_after_send) > 0)
+ UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
} else {
dev_dbg(port->dev, "Setting UART to RS232\n");
/* Disable interrupts */
UART_PUT_IDR(port, atmel_port->tx_done_mask);
- if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
- !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX))
+ if ((port->rs485.flags & SER_RS485_ENABLED) &&
+ !(port->rs485.flags & SER_RS485_RX_DURING_TX))
atmel_start_rx(port);
}
really need this.*/
return;
- if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
- !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX))
+ if ((port->rs485.flags & SER_RS485_ENABLED) &&
+ !(port->rs485.flags & SER_RS485_RX_DURING_TX))
atmel_stop_rx(port);
/* re-enable PDC transmit */
atmel_port->cookie_tx = dmaengine_submit(desc);
} else {
- if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
+ if (port->rs485.flags & SER_RS485_ENABLED) {
/* DMA done, stop TX, start RX for RS485 */
atmel_start_rx(port);
}
config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
config.dst_addr = port->mapbase + ATMEL_US_THR;
- ret = dmaengine_device_control(atmel_port->chan_tx,
- DMA_SLAVE_CONFIG,
- (unsigned long)&config);
+ ret = dmaengine_slave_config(atmel_port->chan_tx,
+ &config);
if (ret) {
dev_err(port->dev, "DMA tx slave configuration failed\n");
goto chan_err;
return -EINVAL;
}
-static void atmel_flip_buffer_rx_dma(struct uart_port *port,
- char *buf, size_t count)
-{
- struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- struct tty_port *tport = &port->state->port;
-
- dma_sync_sg_for_cpu(port->dev,
- &atmel_port->sg_rx,
- 1,
- DMA_DEV_TO_MEM);
-
- tty_insert_flip_string(tport, buf, count);
-
- dma_sync_sg_for_device(port->dev,
- &atmel_port->sg_rx,
- 1,
- DMA_DEV_TO_MEM);
- /*
- * Drop the lock here since it might end up calling
- * uart_start(), which takes the lock.
- */
- spin_unlock(&port->lock);
- tty_flip_buffer_push(tport);
- spin_lock(&port->lock);
-}
-
static void atmel_complete_rx_dma(void *arg)
{
struct uart_port *port = arg;
static void atmel_rx_from_dma(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ struct tty_port *tport = &port->state->port;
struct circ_buf *ring = &atmel_port->rx_ring;
struct dma_chan *chan = atmel_port->chan_rx;
struct dma_tx_state state;
enum dma_status dmastat;
- size_t pending, count;
+ size_t count;
/* Reset the UART timeout early so that we don't miss one */
tasklet_schedule(&atmel_port->tasklet);
return;
}
- /* current transfer size should no larger than dma buffer */
- pending = sg_dma_len(&atmel_port->sg_rx) - state.residue;
- BUG_ON(pending > sg_dma_len(&atmel_port->sg_rx));
+
+ /* CPU claims ownership of RX DMA buffer */
+ dma_sync_sg_for_cpu(port->dev,
+ &atmel_port->sg_rx,
+ 1,
+ DMA_DEV_TO_MEM);
/*
- * This will take the chars we have so far,
- * ring->head will record the transfer size, only new bytes come
- * will insert into the framework.
+ * ring->head points to the end of data already written by the DMA.
+ * ring->tail points to the beginning of data to be read by the
+ * framework.
+ * The current transfer size should not be larger than the dma buffer
+ * length.
*/
- if (pending > ring->head) {
- count = pending - ring->head;
+ ring->head = sg_dma_len(&atmel_port->sg_rx) - state.residue;
+ BUG_ON(ring->head > sg_dma_len(&atmel_port->sg_rx));
+ /*
+ * At this point ring->head may point to the first byte right after the
+ * last byte of the dma buffer:
+ * 0 <= ring->head <= sg_dma_len(&atmel_port->sg_rx)
+ *
+ * However ring->tail must always points inside the dma buffer:
+ * 0 <= ring->tail <= sg_dma_len(&atmel_port->sg_rx) - 1
+ *
+ * Since we use a ring buffer, we have to handle the case
+ * where head is lower than tail. In such a case, we first read from
+ * tail to the end of the buffer then reset tail.
+ */
+ if (ring->head < ring->tail) {
+ count = sg_dma_len(&atmel_port->sg_rx) - ring->tail;
+
+ tty_insert_flip_string(tport, ring->buf + ring->tail, count);
+ ring->tail = 0;
+ port->icount.rx += count;
+ }
- atmel_flip_buffer_rx_dma(port, ring->buf + ring->head, count);
+ /* Finally we read data from tail to head */
+ if (ring->tail < ring->head) {
+ count = ring->head - ring->tail;
- ring->head += count;
- if (ring->head == sg_dma_len(&atmel_port->sg_rx))
+ tty_insert_flip_string(tport, ring->buf + ring->tail, count);
+ /* Wrap ring->head if needed */
+ if (ring->head >= sg_dma_len(&atmel_port->sg_rx))
ring->head = 0;
-
+ ring->tail = ring->head;
port->icount.rx += count;
}
+ /* USART retreives ownership of RX DMA buffer */
+ dma_sync_sg_for_device(port->dev,
+ &atmel_port->sg_rx,
+ 1,
+ DMA_DEV_TO_MEM);
+
+ /*
+ * Drop the lock here since it might end up calling
+ * uart_start(), which takes the lock.
+ */
+ spin_unlock(&port->lock);
+ tty_flip_buffer_push(tport);
+ spin_lock(&port->lock);
+
UART_PUT_IER(port, ATMEL_US_TIMEOUT);
}
config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
config.src_addr = port->mapbase + ATMEL_US_RHR;
- ret = dmaengine_device_control(atmel_port->chan_rx,
- DMA_SLAVE_CONFIG,
- (unsigned long)&config);
+ ret = dmaengine_slave_config(atmel_port->chan_rx,
+ &config);
if (ret) {
dev_err(port->dev, "DMA rx slave configuration failed\n");
goto chan_err;
/* Enable interrupts */
UART_PUT_IER(port, atmel_port->tx_done_mask);
} else {
- if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
- !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX)) {
+ if ((port->rs485.flags & SER_RS485_ENABLED) &&
+ !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
/* DMA done, stop TX, start RX for RS485 */
atmel_start_rx(port);
}
return 0;
}
-static void atmel_init_rs485(struct atmel_uart_port *atmel_port,
+static void atmel_init_rs485(struct uart_port *port,
struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
/* rs485 properties */
if (of_property_read_u32_array(np, "rs485-rts-delay",
rs485_delay, 2) == 0) {
- struct serial_rs485 *rs485conf = &atmel_port->rs485;
+ struct serial_rs485 *rs485conf = &port->rs485;
rs485conf->delay_rts_before_send = rs485_delay[0];
rs485conf->delay_rts_after_send = rs485_delay[1];
rs485conf->flags |= SER_RS485_ENABLED;
}
} else {
- atmel_port->rs485 = pdata->rs485;
+ port->rs485 = pdata->rs485;
}
}
return retval;
}
+/*
+ * Flush any TX data submitted for DMA. Called when the TX circular
+ * buffer is reset.
+ */
+static void atmel_flush_buffer(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ if (atmel_use_pdc_tx(port)) {
+ UART_PUT_TCR(port, 0);
+ atmel_port->pdc_tx.ofs = 0;
+ }
+}
+
/*
* Disable the port
*/
atmel_free_gpio_irq(port);
atmel_port->ms_irq_enabled = false;
-}
-/*
- * Flush any TX data submitted for DMA. Called when the TX circular
- * buffer is reset.
- */
-static void atmel_flush_buffer(struct uart_port *port)
-{
- struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
-
- if (atmel_use_pdc_tx(port)) {
- UART_PUT_TCR(port, 0);
- atmel_port->pdc_tx.ofs = 0;
- }
+ atmel_flush_buffer(port);
}
/*
{
unsigned long flags;
unsigned int mode, imr, quot, baud;
- struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
/* Get current mode register */
mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL
/* Resetting serial mode to RS232 (0x0) */
mode &= ~ATMEL_US_USMODE;
- if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
- if ((atmel_port->rs485.delay_rts_after_send) > 0)
- UART_PUT_TTGR(port,
- atmel_port->rs485.delay_rts_after_send);
+ if (port->rs485.flags & SER_RS485_ENABLED) {
+ if ((port->rs485.delay_rts_after_send) > 0)
+ UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
}
spin_unlock_irqrestore(&port->lock, flags);
}
-static void atmel_set_ldisc(struct uart_port *port, int new)
+static void atmel_set_ldisc(struct uart_port *port, struct ktermios *termios)
{
- if (new == N_PPS) {
+ if (termios->c_line == N_PPS) {
port->flags |= UPF_HARDPPS_CD;
+ spin_lock_irq(&port->lock);
atmel_enable_ms(port);
+ spin_unlock_irq(&port->lock);
} else {
port->flags &= ~UPF_HARDPPS_CD;
+ if (!UART_ENABLE_MS(port, termios->c_cflag)) {
+ spin_lock_irq(&port->lock);
+ atmel_disable_ms(port);
+ spin_unlock_irq(&port->lock);
+ }
}
}
}
#endif
-static int
-atmel_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
-{
- struct serial_rs485 rs485conf;
-
- switch (cmd) {
- case TIOCSRS485:
- if (copy_from_user(&rs485conf, (struct serial_rs485 *) arg,
- sizeof(rs485conf)))
- return -EFAULT;
-
- atmel_config_rs485(port, &rs485conf);
- break;
-
- case TIOCGRS485:
- if (copy_to_user((struct serial_rs485 *) arg,
- &(to_atmel_uart_port(port)->rs485),
- sizeof(rs485conf)))
- return -EFAULT;
- break;
-
- default:
- return -ENOIOCTLCMD;
- }
- return 0;
-}
-
-
-
static struct uart_ops atmel_pops = {
.tx_empty = atmel_tx_empty,
.set_mctrl = atmel_set_mctrl,
.config_port = atmel_config_port,
.verify_port = atmel_verify_port,
.pm = atmel_serial_pm,
- .ioctl = atmel_ioctl,
#ifdef CONFIG_CONSOLE_POLL
.poll_get_char = atmel_poll_get_char,
.poll_put_char = atmel_poll_put_char,
if (!atmel_init_property(atmel_port, pdev))
atmel_set_ops(port);
- atmel_init_rs485(atmel_port, pdev);
+ atmel_init_rs485(port, pdev);
port->iotype = UPIO_MEM;
port->flags = UPF_BOOT_AUTOCONF;
port->dev = &pdev->dev;
port->mapbase = pdev->resource[0].start;
port->irq = pdev->resource[1].start;
+ port->rs485_config = atmel_config_rs485;
tasklet_init(&atmel_port->tasklet, atmel_tasklet_func,
(unsigned long)port);
}
/* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */
- if (atmel_port->rs485.flags & SER_RS485_ENABLED)
+ if (port->rs485.flags & SER_RS485_ENABLED)
atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
else if (atmel_use_pdc_tx(port)) {
port->fifosize = PDC_BUFFER_SIZE;
struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev);
void *data;
int ret = -ENODEV;
+ bool rs485_enabled;
BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE & (ATMEL_SERIAL_RINGSIZE - 1));
port->rx_ring.buf = data;
}
+ rs485_enabled = port->uart.rs485.flags & SER_RS485_ENABLED;
+
ret = uart_add_one_port(&atmel_uart, &port->uart);
if (ret)
goto err_add_port;
device_init_wakeup(&pdev->dev, 1);
platform_set_drvdata(pdev, port);
- if (port->rs485.flags & SER_RS485_ENABLED) {
+ if (rs485_enabled) {
UART_PUT_MR(&port->uart, ATMEL_US_USMODE_NORMAL);
UART_PUT_CR(&port->uart, ATMEL_US_RTSEN);
}
.resume = atmel_serial_resume,
.driver = {
.name = "atmel_usart",
- .owner = THIS_MODULE,
.of_match_table = of_match_ptr(atmel_serial_dt_ids),
},
};
projects / cascardo / linux.git / blobdiff