diff options
| author |   Pali Rohár <pali@kernel.org> | 2021-06-25 00:49:01 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-06-25 13:53:20 +0200 |
| commit | ecd6b010d81f97b06b2f64d2d4f50ebf5acddaa9 (patch) | |
| tree | 702ca207a0b0ee57d95b8f0a9ca663c9a53b937c /drivers/tty | |
| parent | serial: mvebu-uart: fix calculation of clock divisor (diff) | |
| download | linux-dev-ecd6b010d81f97b06b2f64d2d4f50ebf5acddaa9.tar.xz linux-dev-ecd6b010d81f97b06b2f64d2d4f50ebf5acddaa9.zip | |
serial: mvebu-uart: do not allow changing baudrate when uartclk is not available
Testing mvuart->clk for non-error is not enough as mvuart->clk may contain
valid clk pointer but when clk_prepare_enable(mvuart->clk) failed then
port->uartclk is zero.
When mvuart->clk is not available then port->uartclk is zero too.
Parent clock rate port->uartclk is needed to calculate UART clock divisor
and without it is not possible to change baudrate.
So fix test condition when it is possible to change baudrate.
Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate")
Link: https://lore.kernel.org/r/20210624224909.6350-3-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/mvebu-uart.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c index f3ecbcf495ee..1789a6651ec6 100644 --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -445,12 +445,11 @@ static void mvebu_uart_shutdown(struct uart_port *port) static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud) { - struct mvebu_uart *mvuart = to_mvuart(port); unsigned int d_divisor, m_divisor; u32 brdv, osamp; - if (IS_ERR(mvuart->clk)) - return -PTR_ERR(mvuart->clk); + if (!port->uartclk) + return -EOPNOTSUPP; /* * The baudrate is derived from the UART clock thanks to two divisors: |