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-rw-r--r--drivers/tty/serial/sh-sci.c83
1 files changed, 41 insertions, 42 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 3c55600a8236..c5c891c8714e 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -135,6 +135,8 @@ struct sci_port {
struct dma_chan *chan_rx;
#ifdef CONFIG_SERIAL_SH_SCI_DMA
+ struct dma_chan *chan_tx_saved;
+ struct dma_chan *chan_rx_saved;
dma_cookie_t cookie_tx;
dma_cookie_t cookie_rx[2];
dma_cookie_t active_rx;
@@ -1212,25 +1214,16 @@ static int sci_dma_rx_find_active(struct sci_port *s)
return -1;
}
-static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
+static void sci_rx_dma_release(struct sci_port *s)
{
- struct dma_chan *chan = s->chan_rx;
- struct uart_port *port = &s->port;
- unsigned long flags;
+ struct dma_chan *chan = s->chan_rx_saved;
- spin_lock_irqsave(&port->lock, flags);
- s->chan_rx = NULL;
+ s->chan_rx_saved = s->chan_rx = NULL;
s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
- spin_unlock_irqrestore(&port->lock, flags);
dmaengine_terminate_all(chan);
dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
sg_dma_address(&s->sg_rx[0]));
dma_release_channel(chan);
- if (enable_pio) {
- spin_lock_irqsave(&port->lock, flags);
- sci_start_rx(port);
- spin_unlock_irqrestore(&port->lock, flags);
- }
}
static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
@@ -1289,33 +1282,30 @@ static void sci_dma_rx_complete(void *arg)
fail:
spin_unlock_irqrestore(&port->lock, flags);
dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
- sci_rx_dma_release(s, true);
+ /* Switch to PIO */
+ spin_lock_irqsave(&port->lock, flags);
+ s->chan_rx = NULL;
+ sci_start_rx(port);
+ spin_unlock_irqrestore(&port->lock, flags);
}
-static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
+static void sci_tx_dma_release(struct sci_port *s)
{
- struct dma_chan *chan = s->chan_tx;
- struct uart_port *port = &s->port;
- unsigned long flags;
+ struct dma_chan *chan = s->chan_tx_saved;
- spin_lock_irqsave(&port->lock, flags);
- s->chan_tx = NULL;
+ s->chan_tx_saved = s->chan_tx = NULL;
s->cookie_tx = -EINVAL;
- spin_unlock_irqrestore(&port->lock, flags);
dmaengine_terminate_all(chan);
dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
DMA_TO_DEVICE);
dma_release_channel(chan);
- if (enable_pio) {
- spin_lock_irqsave(&port->lock, flags);
- sci_start_tx(port);
- spin_unlock_irqrestore(&port->lock, flags);
- }
}
static void sci_submit_rx(struct sci_port *s)
{
struct dma_chan *chan = s->chan_rx;
+ struct uart_port *port = &s->port;
+ unsigned long flags;
int i;
for (i = 0; i < 2; i++) {
@@ -1347,7 +1337,11 @@ fail:
for (i = 0; i < 2; i++)
s->cookie_rx[i] = -EINVAL;
s->active_rx = -EINVAL;
- sci_rx_dma_release(s, true);
+ /* Switch to PIO */
+ spin_lock_irqsave(&port->lock, flags);
+ s->chan_rx = NULL;
+ sci_start_rx(port);
+ spin_unlock_irqrestore(&port->lock, flags);
}
static void work_fn_tx(struct work_struct *work)
@@ -1357,6 +1351,7 @@ static void work_fn_tx(struct work_struct *work)
struct dma_chan *chan = s->chan_tx;
struct uart_port *port = &s->port;
struct circ_buf *xmit = &port->state->xmit;
+ unsigned long flags;
dma_addr_t buf;
/*
@@ -1378,9 +1373,7 @@ static void work_fn_tx(struct work_struct *work)
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc) {
dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
- /* switch to PIO */
- sci_tx_dma_release(s, true);
- return;
+ goto switch_to_pio;
}
dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
@@ -1393,15 +1386,21 @@ static void work_fn_tx(struct work_struct *work)
s->cookie_tx = dmaengine_submit(desc);
if (dma_submit_error(s->cookie_tx)) {
dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
- /* switch to PIO */
- sci_tx_dma_release(s, true);
- return;
+ goto switch_to_pio;
}
dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
__func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
dma_async_issue_pending(chan);
+ return;
+
+switch_to_pio:
+ spin_lock_irqsave(&port->lock, flags);
+ s->chan_tx = NULL;
+ sci_start_tx(port);
+ spin_unlock_irqrestore(&port->lock, flags);
+ return;
}
static enum hrtimer_restart rx_timer_fn(struct hrtimer *t)
@@ -1535,7 +1534,6 @@ static void sci_request_dma(struct uart_port *port)
chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
if (chan) {
- s->chan_tx = chan;
/* UART circular tx buffer is an aligned page. */
s->tx_dma_addr = dma_map_single(chan->device->dev,
port->state->xmit.buf,
@@ -1544,11 +1542,13 @@ static void sci_request_dma(struct uart_port *port)
if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
dma_release_channel(chan);
- s->chan_tx = NULL;
+ chan = NULL;
} else {
dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
__func__, UART_XMIT_SIZE,
port->state->xmit.buf, &s->tx_dma_addr);
+
+ s->chan_tx_saved = s->chan_tx = chan;
}
INIT_WORK(&s->work_tx, work_fn_tx);
@@ -1561,8 +1561,6 @@ static void sci_request_dma(struct uart_port *port)
dma_addr_t dma;
void *buf;
- s->chan_rx = chan;
-
s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
&dma, GFP_KERNEL);
@@ -1570,7 +1568,6 @@ static void sci_request_dma(struct uart_port *port)
dev_warn(port->dev,
"Failed to allocate Rx dma buffer, using PIO\n");
dma_release_channel(chan);
- s->chan_rx = NULL;
return;
}
@@ -1591,6 +1588,8 @@ static void sci_request_dma(struct uart_port *port)
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
sci_submit_rx(s);
+
+ s->chan_rx_saved = s->chan_rx = chan;
}
}
@@ -1598,10 +1597,10 @@ static void sci_free_dma(struct uart_port *port)
{
struct sci_port *s = to_sci_port(port);
- if (s->chan_tx)
- sci_tx_dma_release(s, false);
- if (s->chan_rx)
- sci_rx_dma_release(s, false);
+ if (s->chan_tx_saved)
+ sci_tx_dma_release(s);
+ if (s->chan_rx_saved)
+ sci_rx_dma_release(s);
}
static void sci_flush_buffer(struct uart_port *port)
@@ -2092,7 +2091,7 @@ static void sci_shutdown(struct uart_port *port)
spin_unlock_irqrestore(&port->lock, flags);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
- if (s->chan_rx) {
+ if (s->chan_rx_saved) {
dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
port->line);
hrtimer_cancel(&s->rx_timer);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-23 15:19:47 +0300