From 67c0472297b2c7baf87f84ed8c4572f60421d736 Mon Sep 17 00:00:00 2001
From: Peter Galka <peter.galka@wago.com>
Date: Wed, 22 Oct 2025 08:10:16 +0200
Subject: [PATCH] drivers: spi: kbus: split interrupt handling

Signed-off-by: Peter Galka <peter.galka@wago.com>
---
 arch/arm64/boot/dts/ti/k3-am62x-pfc.dtsi |  1 +
 drivers/spi/spi-kbus.c                   | 47 +++++++++++++++++++-----
 include/linux/spi/kbus.h                 |  1 +
 3 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/boot/dts/ti/k3-am62x-pfc.dtsi b/arch/arm64/boot/dts/ti/k3-am62x-pfc.dtsi
index e81e78ce25fa..ec0fb9c27485 100644
--- a/arch/arm64/boot/dts/ti/k3-am62x-pfc.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62x-pfc.dtsi
@@ -743,6 +743,7 @@
 		spi-max-frequency = <10000000>;
 
 		kbus,reset-on-boot;
+		kbus,renesas;
 
 		/*
 		 * kbus,cmdsel-gpio is used to signal the need for an update
diff --git a/drivers/spi/spi-kbus.c b/drivers/spi/spi-kbus.c
index 2f1a1bbc3c6c..f2f41de82d8b 100644
--- a/drivers/spi/spi-kbus.c
+++ b/drivers/spi/spi-kbus.c
@@ -37,6 +37,8 @@
 #define KBUS_DUMMY_BIT_PER_WORD 8
 #define KBUS_DUMMY_SPEED 1000000
 
+#define KBUS_CMD_UPDATE 0xa3
+
 #if KBUS_TESTING
 struct wago_trace_data wago_ktest;
 #endif
@@ -107,7 +109,21 @@ int kbus_wait_for_event(int *event)
 	return 0;
 }
 
-static irqreturn_t kbus_isr(int irq, void *dev)
+static irqreturn_t kbus_infineon_isr(int irq, void *dev)
+{
+	struct kbus_drv_data *kdrvdata = dev_get_drvdata(kbus_device);
+
+	trace_pxc_kbus(__func__, "kbus-irq:in");
+	kdrvdata->kbus_irq_state = 0; /* attention: changed polarisation */
+
+	/* wake_up_interruptible(&kdrvdata->kbus_irq_wq); */
+	wake_up(&kdrvdata->kbus_irq_wq);
+
+	trace_pxc_kbus(__func__, "kbus-irq:out");
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t kbus_renesas_isr(int irq, void *dev)
 {
 	struct kbus_drv_data *kdrvdata = dev_get_drvdata(kbus_device);
 
@@ -664,7 +680,7 @@ static long kbus_ioctl(struct file *file, uint cmd, ulong arg)
 	case KBUS_IOC_CMD: /* FIXME */
 	{
 		struct kbus_cmd kcmd;
-		struct kbus_cmd __user *kcmd_user;
+		struct kbus_cmd __user *kcmd_user = (struct kbus_cmd __user *)arg;
 
 		trace_pxc_kbus(__func__,
 			       "KCMD: Enter: Set kbus_irq_state to 1.");
@@ -679,19 +695,21 @@ static long kbus_ioctl(struct file *file, uint cmd, ulong arg)
 		/* Indicate Transfer Start */
 		gpiod_set_value(kdrvdata->gpio_nirq, 0);
 
-		kcmd_user = (struct kbus_cmd __user *)arg;
-
-		if ((int)*kcmd_user->tx_buf == 0xA3) {
-			kdrvdata->kbus_ign_irq = 1;
-			trace_pxc_kbus(__func__, "KCMD: A3: Update cmd");
-		}
-
 		if (copy_from_user(&kcmd, kcmd_user, sizeof(kcmd))) {
 			/* release the irq pin */
 			gpiod_set_value(kdrvdata->gpio_nirq, 1);
 			return -EFAULT;
 		}
 
+		u8 tx_byte;
+		if (!copy_from_user(&tx_byte, kcmd.tx_buf, sizeof(tx_byte))) {
+			if ((int)tx_byte == KBUS_CMD_UPDATE) {
+				kdrvdata->kbus_ign_irq = 1;
+				trace_pxc_kbus(__func__, "KCMD: Update cmd (0xa3)");
+				pr_info("%s: KCMD: Update cmd (0xa3)\n", __func__);
+			}
+		}
+
 		ret = kbus_cmd_txrx(&kcmd);
 		if (ret < 0) {
 			/* release the irq pin */
@@ -1100,6 +1118,8 @@ static struct kbus_drv_data *kbus_probe_dt(struct spi_device *spi)
 		}
 	}
 
+	kdrvdata->kbus_renesas = of_property_read_bool(np, "kbus,renesas");
+
 	kdrvdata->kbus_irq = gpiod_to_irq(kdrvdata->gpio_nrdy);
 	kdrvdata->spi = spi;
 
@@ -1127,6 +1147,7 @@ static int kbus_probe(struct spi_device *spi)
 	int ret = 0;
 	u8 save = 0;
 	struct kbus_drv_data *kdrvdata;
+	irqreturn_t (*kbus_isr)(int, void *);
 
 	if (!spi->dev.of_node) {
 		pr_err("WAGO KBUS Driver: No DT node found!\n");
@@ -1139,6 +1160,14 @@ static int kbus_probe(struct spi_device *spi)
 
 	init_waitqueue_head(&kdrvdata->kbus_irq_wq);
 
+	if (kdrvdata->kbus_renesas)
+		kbus_isr = kbus_renesas_isr;
+	else
+		kbus_isr = kbus_infineon_isr;
+
+	pr_info("%s: %s is used\n", __func__, kdrvdata->kbus_renesas?
+		"renesas" : "infineon");
+
 	ret = request_irq(kdrvdata->kbus_irq, kbus_isr,
 			  IRQF_SHARED | IRQ_TYPE_EDGE_BOTH,
 			  "kbus", &kbus_dev);
diff --git a/include/linux/spi/kbus.h b/include/linux/spi/kbus.h
index 4b3612d858f2..6a05735ad454 100644
--- a/include/linux/spi/kbus.h
+++ b/include/linux/spi/kbus.h
@@ -98,6 +98,7 @@ struct kbus_drv_data {
 	wait_queue_head_t kbus_irq_wq;
 	struct spi_device *spi;
 	const char *kbus_tty_device_name;
+	bool kbus_renesas;
 };
 
 /* For userspace ioctl communication */