openwrt/target/linux/brcm2708/patches-4.19/950-0551-spi-bcm2835-enable-shared-interrupt-support.patch

From 9d848c0af8245c674ad7a91d157362334e822361 Mon Sep 17 00:00:00 2001
From: Martin Sperl <kernel@martin.sperl.org>
Date: Mon, 13 May 2019 11:05:27 +0000
Subject: [PATCH 551/773] spi: bcm2835: enable shared interrupt support

Add shared interrupt support for this driver.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
---
 drivers/spi/spi-bcm2835.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -150,6 +150,10 @@ static irqreturn_t bcm2835_spi_interrupt
 	struct spi_master *master = dev_id;
 	struct bcm2835_spi *bs = spi_master_get_devdata(master);
 
+	/* check if we got interrupt enabled */
+	if (!(bcm2835_rd(bs, BCM2835_SPI_CS) & BCM2835_SPI_CS_INTR))
+		return IRQ_NONE;
+
 	/* Read as many bytes as possible from FIFO */
 	bcm2835_rd_fifo(bs);
 	/* Write as many bytes as possible to FIFO */
@@ -756,7 +760,8 @@ static int bcm2835_spi_probe(struct plat
 	bcm2835_wr(bs, BCM2835_SPI_CS,
 		   BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX);
 
-	err = devm_request_irq(&pdev->dev, bs->irq, bcm2835_spi_interrupt, 0,
+	err = devm_request_irq(&pdev->dev, bs->irq, bcm2835_spi_interrupt,
+			       IRQF_SHARED,
 			       dev_name(&pdev->dev), master);
 	if (err) {
 		dev_err(&pdev->dev, "could not request IRQ: %d\n", err);