[PATCH 8/8] tty: stm32-usart: Use devm_clk_get_enabled() helpers

Lei Liu
2024-08-22T03:42:00Z

The devm_clk_get_enabled() helpers:
- call devm_clk_get()
- call clk_prepare_enable() and register what is needed in order to
call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids calls to clk_disable_unprepare().

Signed-off-by: Lei Liu <liulei.rjpt@vivo.com>
---
drivers/tty/serial/stm32-usart.c | 16 +---------------
1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index e1e7bc04c579..9bce3159165a 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -1550,11 +1550,6 @@ static int stm32_usart_get_ftcfg(struct platform_device *pdev, struct stm32_port
return fifo_size;
}

-static void stm32_usart_deinit_port(struct stm32_port *stm32port)
-{
- clk_disable_unprepare(stm32port->clk);
-}
-
static const struct serial_rs485 stm32_rs485_supported = {
.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND |
SER_RS485_RX_DURING_TX,
@@ -1599,15 +1594,10 @@ static int stm32_usart_init_port(struct stm32_port *stm32port,

spin_lock_init(&port->lock);

- stm32port->clk = devm_clk_get(&pdev->dev, NULL);
+ stm32port->clk = devm_clk_get_enabled(&pdev->dev, NULL);
if (IS_ERR(stm32port->clk))
return PTR_ERR(stm32port->clk);

- /* Ensure that clk rate is correct by enabling the clk */
- ret = clk_prepare_enable(stm32port->clk);
- if (ret)
- return ret;
-
stm32port->port.uartclk = clk_get_rate(stm32port->clk);
if (!stm32port->port.uartclk) {
ret = -EINVAL;
@@ -1645,7 +1635,6 @@ static int stm32_usart_init_port(struct stm32_port *stm32port,
return ret;

err_clk:
- clk_disable_unprepare(stm32port->clk);

return ret;
}
@@ -1853,8 +1842,6 @@ static int stm32_usart_serial_probe(struct platform_device *pdev)
if (stm32port->wakeup_src)
device_set_wakeup_capable(&pdev->dev, false);

- stm32_usart_deinit_port(stm32port);
-
err_dma_tx:
if (stm32port->tx_ch)
dma_release_channel(stm32port->tx_ch);
@@ -1904,7 +1891,6 @@ static void stm32_usart_serial_remove(struct platform_device *pdev)
device_init_wakeup(&pdev->dev, false);
}

- stm32_usart_deinit_port(stm32_port);
}

static void __maybe_unused stm32_usart_console_putchar(struct uart_port *port, unsigned char ch)
--
2.34.1