bcm27xx: add support for linux v5.15

Build system: x86_64
Build-tested: bcm2708, bcm2709, bcm2710, bcm2711
Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B

Signed-off-by: Marty Jones <mj8263788@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.15/950-0041-dmaengine-bcm2835-Load-driver-early-and-support-lega.patch b/target/linux/bcm27xx/patches-5.15/950-0041-dmaengine-bcm2835-Load-driver-early-and-support-lega.patch
new file mode 100644
index 0000000000..2fc669ba9d
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.15/950-0041-dmaengine-bcm2835-Load-driver-early-and-support-lega.patch
@@ -0,0 +1,101 @@
+From 6d73f2ff2b8fdd774be0430577aed7f08478d541 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org>
+Date: Sat, 3 Oct 2015 22:22:55 +0200
+Subject: [PATCH] dmaengine: bcm2835: Load driver early and support
+ legacy API
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Load driver early since at least bcm2708_fb doesn't support deferred
+probing and even if it did, we don't want the video driver deferred.
+Support the legacy DMA API which is needed by bcm2708_fb.
+Don't mask out channel 2.
+
+Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
+---
+ drivers/dma/Kconfig       |  2 +-
+ drivers/dma/bcm2835-dma.c | 26 +++++++++++++++++++++++++-
+ 2 files changed, 26 insertions(+), 2 deletions(-)
+
+--- a/drivers/dma/Kconfig
++++ b/drivers/dma/Kconfig
+@@ -127,7 +127,7 @@ config BCM_SBA_RAID
+ 
+ config DMA_BCM2835
+ 	tristate "BCM2835 DMA engine support"
+-	depends on ARCH_BCM2835
++	depends on ARCH_BCM2835 || ARCH_BCM2708 || ARCH_BCM2709
+ 	select DMA_ENGINE
+ 	select DMA_VIRTUAL_CHANNELS
+ 
+--- a/drivers/dma/bcm2835-dma.c
++++ b/drivers/dma/bcm2835-dma.c
+@@ -25,6 +25,7 @@
+ #include <linux/interrupt.h>
+ #include <linux/list.h>
+ #include <linux/module.h>
++#include <linux/platform_data/dma-bcm2708.h>
+ #include <linux/platform_device.h>
+ #include <linux/slab.h>
+ #include <linux/io.h>
+@@ -36,6 +37,7 @@
+ 
+ #define BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED 14
+ #define BCM2835_DMA_CHAN_NAME_SIZE 8
++#define BCM2835_DMA_BULK_MASK  BIT(0)
+ 
+ /**
+  * struct bcm2835_dmadev - BCM2835 DMA controller
+@@ -906,6 +908,9 @@ static int bcm2835_dma_probe(struct plat
+ 	base = devm_ioremap_resource(&pdev->dev, res);
+ 	if (IS_ERR(base))
+ 		return PTR_ERR(base);
++	rc = bcm_dmaman_probe(pdev, base, BCM2835_DMA_BULK_MASK);
++	if (rc)
++		dev_err(&pdev->dev, "Failed to initialize the legacy API\n");
+ 
+ 	od->base = base;
+ 
+@@ -951,6 +956,9 @@ static int bcm2835_dma_probe(struct plat
+ 		goto err_no_dma;
+ 	}
+ 
++	/* Channel 0 is used by the legacy API */
++	chans_available &= ~BCM2835_DMA_BULK_MASK;
++
+ 	/* get irqs for each channel that we support */
+ 	for (i = 0; i <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; i++) {
+ 		/* skip masked out channels */
+@@ -1025,6 +1033,7 @@ static int bcm2835_dma_remove(struct pla
+ {
+ 	struct bcm2835_dmadev *od = platform_get_drvdata(pdev);
+ 
++	bcm_dmaman_remove(pdev);
+ 	dma_async_device_unregister(&od->ddev);
+ 	bcm2835_dma_free(od);
+ 
+@@ -1040,7 +1049,22 @@ static struct platform_driver bcm2835_dm
+ 	},
+ };
+ 
+-module_platform_driver(bcm2835_dma_driver);
++static int bcm2835_dma_init(void)
++{
++	return platform_driver_register(&bcm2835_dma_driver);
++}
++
++static void bcm2835_dma_exit(void)
++{
++	platform_driver_unregister(&bcm2835_dma_driver);
++}
++
++/*
++ * Load after serial driver (arch_initcall) so we see the messages if it fails,
++ * but before drivers (module_init) that need a DMA channel.
++ */
++subsys_initcall(bcm2835_dma_init);
++module_exit(bcm2835_dma_exit);
+ 
+ MODULE_ALIAS("platform:bcm2835-dma");
+ MODULE_DESCRIPTION("BCM2835 DMA engine driver");