| Message ID | 20211221071634.25980-2-yu.tu@amlogic.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | the UART driver compatible with the Amlogic Meson S4 SoC | expand |
On Tue, Dec 21, 2021 at 03:16:32PM +0800, Yu Tu wrote: > Change request_irq to devm_request_irq and free_irq to devm_free_irq. > It's better to change the code this way. Why? What did this fix up? You still are manually requesting and freeing the irq. What bug did you fix? > > The IRQF_SHARED interrupt flag was added because an interrupt error was > detected when the serial port was opened twice in a row on the project. That is a different change. Make that a different patch. thanks, greg k-h
On 2021/12/21 15:30, Greg Kroah-Hartman wrote: > [ EXTERNAL EMAIL ] > > On Tue, Dec 21, 2021 at 03:16:32PM +0800, Yu Tu wrote: >> Change request_irq to devm_request_irq and free_irq to devm_free_irq. >> It's better to change the code this way. > > Why? What did this fix up? You still are manually requesting and > freeing the irq. What bug did you fix? > I think this is exactly what you said. It's not necessary. >> >> The IRQF_SHARED interrupt flag was added because an interrupt error was >> detected when the serial port was opened twice in a row on the project. > > That is a different change. Make that a different patch. > The main purpose of this change is that I found some users in the actual project with the following usages: (1)open(/dev/ttyAML0); (2)open(/dev/ttyAML0); The open function calls the meson_uart_startup function. If this is the case, an interrupt error is reported.So So the IRQF_SHARED flag was added. I'm going to do this for now, remove free_irq and request_irq function,then add devm_request_irq in meson_uart_probe function. This solves the above problem without adding IRQF_SHARED. > thanks, > > greg k-h >
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index d2c08b760f83..02fafb8229d2 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -121,7 +121,7 @@ static void meson_uart_shutdown(struct uart_port *port) unsigned long flags; u32 val; - free_irq(port->irq, port); + devm_free_irq(port->dev, port->irq, port); spin_lock_irqsave(&port->lock, flags); @@ -287,8 +287,8 @@ static int meson_uart_startup(struct uart_port *port) val = (AML_UART_RECV_IRQ(1) | AML_UART_XMIT_IRQ(port->fifosize / 2)); writel(val, port->membase + AML_UART_MISC); - ret = request_irq(port->irq, meson_uart_interrupt, 0, - port->name, port); + ret = devm_request_irq(port->dev, port->irq, meson_uart_interrupt, + IRQF_SHARED, port->name, port); return ret; }
Change request_irq to devm_request_irq and free_irq to devm_free_irq. It's better to change the code this way. The IRQF_SHARED interrupt flag was added because an interrupt error was detected when the serial port was opened twice in a row on the project. Signed-off-by: Yu Tu <yu.tu@amlogic.com> --- drivers/tty/serial/meson_uart.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)