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

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

[Bing Fan]

From: Bing Fan <tombinfan@tencent.com>

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 <tombinfan@tencent.com>
---
 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

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

[Greg KH]

On Wed, Jun 30, 2021 at 09:55:53AM +0800, Bing Fan wrote:
> From: Bing Fan <tombinfan@tencent.com>
> 
> 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 <tombinfan@tencent.com>
> ---
>  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