[PATCH 1/8] serial: stm32: fix -Wall W=1 compilation warnings

Erwan Le Ray
2020-12-18T19:01:45Z

Fix compilations warning detected by -Wall W=1 compilation option:
- warning: variable ‘cookie’ set but not used

Fixes: 3489187204eb ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index ee6c7762d355..6248304a001f 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -350,7 +350,6 @@ static void stm32_transmit_chars_dma(struct uart_port *port)
struct stm32_usart_offsets *ofs = &stm32port->info->ofs;
struct circ_buf *xmit = &port->state->xmit;
struct dma_async_tx_descriptor *desc = NULL;
- dma_cookie_t cookie;
unsigned int count, i;

if (stm32port->tx_dma_busy)
@@ -384,17 +383,18 @@ static void stm32_transmit_chars_dma(struct uart_port *port)
DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT);

- if (!desc) {
- for (i = count; i > 0; i--)
- stm32_transmit_chars_pio(port);
- return;
- }
+ if (!desc)
+ goto fallback_err;

desc->callback = stm32_tx_dma_complete;
desc->callback_param = port;

/* Push current DMA TX transaction in the pending queue */
- cookie = dmaengine_submit(desc);
+ if (dma_submit_error(dmaengine_submit(desc))) {
+ /* dma no yet started, safe to free resources */
+ dmaengine_terminate_async(stm32port->tx_ch);
+ goto fallback_err;
+ }

/* Issue pending DMA TX requests */
dma_async_issue_pending(stm32port->tx_ch);
@@ -403,6 +403,11 @@ static void stm32_transmit_chars_dma(struct uart_port *port)

xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
port->icount.tx += count;
+ return;
+
+fallback_err:
+ for (i = count; i > 0; i--)
+ stm32_transmit_chars_pio(port);
}

static void stm32_transmit_chars(struct uart_port *port)
@@ -1087,7 +1092,6 @@ static int stm32_of_dma_rx_probe(struct stm32_port *stm32port,
struct device *dev = &pdev->dev;
struct dma_slave_config config;
struct dma_async_tx_descriptor *desc = NULL;
- dma_cookie_t cookie;
int ret;

/* Request DMA RX channel */
@@ -1132,7 +1136,11 @@ static int stm32_of_dma_rx_probe(struct stm32_port *stm32port,
desc->callback_param = NULL;

/* Push current DMA transaction in the pending queue */
- cookie = dmaengine_submit(desc);
+ ret = dma_submit_error(dmaengine_submit(desc));
+ if (ret) {
+ dmaengine_terminate_sync(stm32port->rx_ch);
+ goto config_err;
+ }

/* Issue pending DMA requests */
dma_async_issue_pending(stm32port->rx_ch);
--
2.17.1