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, 51 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.15/950-0285-media-bcm2835-unicam-Always-service-interrupts.patch b/target/linux/bcm27xx/patches-5.15/950-0285-media-bcm2835-unicam-Always-service-interrupts.patch
new file mode 100644
index 0000000000..8872cc931b
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.15/950-0285-media-bcm2835-unicam-Always-service-interrupts.patch
@@ -0,0 +1,51 @@
+From cfd60149f96e3021e07c2ee792312b176dd6a23b Mon Sep 17 00:00:00 2001
+From: Dave Stevenson <dave.stevenson@raspberrypi.com>
+Date: Wed, 13 May 2020 18:28:27 +0100
+Subject: [PATCH] media: bcm2835-unicam: Always service interrupts
+
+From when bringing up the driver, there was a check in the isr
+to ignore interrupts (claiming them handled) should the driver
+not be streaming.
+
+The VPU now will not register a camera driver if it finds a
+CSI2 node enabled in device tree, therefore this flawed check is
+redundant.
+
+https://github.com/raspberrypi/linux/issues/3602
+
+Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
+---
+ drivers/media/platform/bcm2835/bcm2835-unicam.c | 15 ---------------
+ 1 file changed, 15 deletions(-)
+
+--- a/drivers/media/platform/bcm2835/bcm2835-unicam.c
++++ b/drivers/media/platform/bcm2835/bcm2835-unicam.c
+@@ -782,12 +782,6 @@ static bool unicam_all_nodes_streaming(s
+ 	return ret;
+ }
+ 
+-static bool unicam_all_nodes_disabled(struct unicam_device *dev)
+-{
+-	return !dev->node[IMAGE_PAD].streaming &&
+-	       !dev->node[METADATA_PAD].streaming;
+-}
+-
+ static void unicam_queue_event_sof(struct unicam_device *unicam)
+ {
+ 	struct v4l2_event event = {
+@@ -815,15 +809,6 @@ static irqreturn_t unicam_isr(int irq, v
+ 	u32 ista, sta;
+ 	u64 ts;
+ 
+-	/*
+-	 * Don't service interrupts if not streaming.
+-	 * Avoids issues if the VPU should enable the
+-	 * peripheral without the kernel knowing (that
+-	 * shouldn't happen, but causes issues if it does).
+-	 */
+-	if (unicam_all_nodes_disabled(unicam))
+-		return IRQ_NONE;
+-
+ 	sta = reg_read(unicam, UNICAM_STA);
+ 	/* Write value back to clear the interrupts */
+ 	reg_write(unicam, UNICAM_STA, sta);