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

[bing fan <hptsfb@gmail.com>]

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 <hptsfb@gmail.com>
---
 drivers/tty/serial/amba-pl011.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 78682c12156a..2b6f43c27dea 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1703,9 +1703,30 @@ 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 = -1;
+       int i = 0;
+       unsigned int virq = 0;
+       struct amba_device *amba_dev = (struct amba_device *)uap->port.dev;
+
+       if (!amba_dev)
+               return -1;
+
        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)          // request irq until virq is 0
+                       break;
+
+               ret = request_irq(virq, pl011_int, IRQF_SHARED,
"uart-pl011-*", uap);
+               if (ret < 0) {
+                       dev_info(uap->port.dev, "%s %d request %u
interrupt failed\n",
+                                       __func__, __LINE__, virq);
+                       break;
+               }
+       }
+
+       return ret;
 }

 /*
-- 
2.17.1