serial: stm32: use DMAT as a configuration bit

DMAT is a configuration bit so it should be set at the startup of uart
port and not when a DMA transfer begins.

This patch move set of DMAT into set_termios and remove DMAT reset except
in shutdown.

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230808161906.178996-3-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Valentin Caron 2023-08-08 18:19:02 +02:00 committed by Greg Kroah-Hartman
parent db89728aba
commit 00bc5e8fc9

View file

@ -510,10 +510,8 @@ static void stm32_usart_tx_dma_complete(void *arg)
{
struct uart_port *port = arg;
struct stm32_port *stm32port = to_stm32_port(port);
const struct stm32_usart_offsets *ofs = &stm32port->info->ofs;
unsigned long flags;
stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT);
stm32_usart_tx_dma_terminate(stm32port);
/* Let's see if we have pending data to send */
@ -602,7 +600,6 @@ static void stm32_usart_transmit_chars_pio(struct uart_port *port)
static void stm32_usart_transmit_chars_dma(struct uart_port *port)
{
struct stm32_port *stm32port = to_stm32_port(port);
const struct stm32_usart_offsets *ofs = &stm32port->info->ofs;
struct circ_buf *xmit = &port->state->xmit;
struct dma_async_tx_descriptor *desc = NULL;
unsigned int count;
@ -667,8 +664,6 @@ static void stm32_usart_transmit_chars_dma(struct uart_port *port)
/* Issue pending DMA TX requests */
dma_async_issue_pending(stm32port->tx_ch);
stm32_usart_set_bits(port, ofs->cr3, USART_CR3_DMAT);
uart_xmit_advance(port, count);
return;
@ -1270,6 +1265,9 @@ static void stm32_usart_set_termios(struct uart_port *port,
cr3 |= USART_CR3_DDRE;
}
if (stm32_port->tx_ch)
cr3 |= USART_CR3_DMAT;
if (rs485conf->flags & SER_RS485_ENABLED) {
stm32_usart_config_reg_rs485(&cr1, &cr3,
rs485conf->delay_rts_before_send,