2021-06-30 02:26:00

by Bing Fan

Subject: [PATCH v3] arm pl011 serial: support multi-irq request

From: Bing Fan <[email protected]>

In order to make pl011 work better, multiple interrupts are
required, such as TXIM, RXIM, RTIM, error interrupt(FE/PE/BE/OE);
at the same time, pl011 to GIC does not merge the interrupt
lines(each serial-interrupt corresponding to different GIC hardware
interrupt), so need to enable and request multiple gic interrupt
numbers in the driver.

Signed-off-by: Bing Fan <[email protected]>
---
drivers/tty/serial/amba-pl011.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 78682c12156a..8b471de0e31c 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1703,9 +1703,26 @@ static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h)

static int pl011_allocate_irq(struct uart_amba_port *uap)
{
+ int ret = 0;
+ int i;
+ unsigned int virq;
+ struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
+
pl011_write(uap->im, uap, REG_IMSC);

- return request_irq(uap->port.irq, pl011_int, IRQF_SHARED, "uart-pl011", uap);
+ for (i = 0; i < AMBA_NR_IRQS; i++) {
+ virq = amba_dev->irq[i];
+ if (virq == 0)
+ break;
+
+ ret = request_irq(virq, pl011_int, IRQF_SHARED, "uart-pl011-*", uap);
+ if (ret) {
+ dev_err(uap->port.dev, "request %u interrupt failed\n", virq);
+ break;
+ }
+ }
+
+ return ret;
}

/*
--
2.17.1

2021-06-30 09:11:02

by Greg KH

Subject: Re: [PATCH v3] arm pl011 serial: support multi-irq request

On Wed, Jun 30, 2021 at 09:55:53AM +0800, Bing Fan wrote:
> From: Bing Fan <[email protected]>
>
> In order to make pl011 work better, multiple interrupts are
> required, such as TXIM, RXIM, RTIM, error interrupt(FE/PE/BE/OE);
> at the same time, pl011 to GIC does not merge the interrupt
> lines(each serial-interrupt corresponding to different GIC hardware
> interrupt), so need to enable and request multiple gic interrupt
> numbers in the driver.
>
> Signed-off-by: Bing Fan <[email protected]>
> ---
> drivers/tty/serial/amba-pl011.c | 19 ++++++++++++++++++-
> 1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> index 78682c12156a..8b471de0e31c 100644
> --- a/drivers/tty/serial/amba-pl011.c
> +++ b/drivers/tty/serial/amba-pl011.c
> @@ -1703,9 +1703,26 @@ static void pl011_write_lcr_h(struct uart_amba_port *uap, unsigned int lcr_h)
>
> static int pl011_allocate_irq(struct uart_amba_port *uap)
> {
> + int ret = 0;
> + int i;
> + unsigned int virq;
> + struct amba_device *amba_dev = container_of(uap->port.dev, struct amba_device, dev);
> +
> pl011_write(uap->im, uap, REG_IMSC);
>
> - return request_irq(uap->port.irq, pl011_int, IRQF_SHARED, "uart-pl011", uap);
> + for (i = 0; i < AMBA_NR_IRQS; i++) {
> + virq = amba_dev->irq[i];
> + if (virq == 0)
> + break;
> +
> + ret = request_irq(virq, pl011_int, IRQF_SHARED, "uart-pl011-*", uap);
> + if (ret) {
> + dev_err(uap->port.dev, "request %u interrupt failed\n", virq);
> + break;

No error handling to put back the irq you requested if an error happens?
That feels like a memory leak...

thanks,

greg k-h