[PATCH net-next v3] net: stmmac: Add support for TX/RX channel interrupt

[muhammad.nazim.amirul.nazle.asmade@altera.com]

From: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>

Enable TX/RX channel interrupt registration for MAC that interrupts CPU
through shared peripheral interrupt (SPI).

Per-channel interrupts and interrupt-names are registered as follows,
e.g. 4 TX and 4 RX channels:
interrupts = <GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 104 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 105 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 106 IRQ_TYPE_LEVEL_HIGH>,
             <GIC_SPI 107 IRQ_TYPE_LEVEL_HIGH>;
interrupt-names = "dma_tx0",
                  "dma_tx1",
                  "dma_tx2",
                  "dma_tx3",
                  "dma_rx0",
                  "dma_rx1",
                  "dma_rx2",
                  "dma_rx3";

Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>
---
Changes in v3:
- Add net-next tree prefix to subject line.
- Fix variable declarations to follow Reverse Christmas Tree order.

Changes in v2:
- Use -ENXIO to detect when interrupt name is not present,
  and return any other negative error code to the caller.
---
 .../ethernet/stmicro/stmmac/stmmac_platform.c | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 5cae2aa72906..9039e207ddbd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -732,6 +732,9 @@ static int stmmac_pltfr_get_irq_array(struct platform_device *pdev,
 int stmmac_get_platform_resources(struct platform_device *pdev,
 				  struct stmmac_resources *stmmac_res)
 {
+	char irq_name[9];
+	int ret;
+	int irq;
+	int i;
 
 	memset(stmmac_res, 0, sizeof(*stmmac_res));
@@ -767,6 +770,30 @@ int stmmac_get_platform_resources(struct platform_device *pdev,
 		dev_info(&pdev->dev, "IRQ sfty not found\n");
 	}
 
+	/* For RX Channel */
+	for (i = 0; i < MTL_MAX_RX_QUEUES; i++) {
+		snprintf(irq_name, sizeof(irq_name), "dma_rx%i", i);
+		irq = platform_get_irq_byname_optional(pdev, irq_name);
+		if (irq == -ENXIO)
+			break;
+		else if (irq < 0)
+			return irq;
+
+		stmmac_res->rx_irq[i] = irq;
+	}
+
+	/* For TX Channel */
+	for (i = 0; i < MTL_MAX_TX_QUEUES; i++) {
+		snprintf(irq_name, sizeof(irq_name), "dma_tx%i", i);
+		irq = platform_get_irq_byname_optional(pdev, irq_name);
+		if (irq == -ENXIO)
+			break;
+		else if (irq < 0)
+			return irq;
+
+		stmmac_res->tx_irq[i] = irq;
+	}
+
 	stmmac_res->addr = devm_platform_ioremap_resource(pdev, 0);
 
 	if (IS_ERR(stmmac_res->addr))
-- 
2.43.7