[PATCH 6/6] i2c: riic: Add support for RZ/T2H SoC

Prabhakar
2025-05-30T14:31:56Z

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Add support for the Renesas RZ/T2H (R9A09G077) SoC, which features a
different interrupt layout for the RIIC controller. Unlike other SoCs
with individual error interrupts, RZ/T2H uses a combined error interrupt
(EEI).

Introduce a new IRQ descriptor table for RZ/T2H, along with a custom
ISR (`riic_eei_isr`) to handle STOP and NACK detection from the shared
interrupt.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
drivers/i2c/busses/i2c-riic.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)

diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c
index a4df00cb470c..1f9299f5effa 100644
--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -79,6 +79,7 @@
#define ICIER_SPIE BIT(3)

#define ICSR2_NACKF BIT(4)
+#define ICSR2_STOP BIT(3)

#define ICBR_RESERVED GENMASK(7, 5) /* Should be 1 on writes */

@@ -326,6 +327,19 @@ static irqreturn_t riic_stop_isr(int irq, void *data)
return IRQ_HANDLED;
}

+static irqreturn_t riic_eei_isr(int irq, void *data)
+{
+ u8 icsr2 = riic_readb(data, RIIC_ICSR2);
+
+ if (icsr2 & ICSR2_NACKF)
+ return riic_tend_isr(irq, data);
+
+ if (icsr2 & ICSR2_STOP)
+ return riic_stop_isr(irq, data);
+
+ return IRQ_NONE;
+}
+
static u32 riic_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
@@ -497,6 +511,13 @@ static const struct riic_irq_desc riic_irqs[] = {
{ .res_num = 5, .isr = riic_tend_isr, .name = "riic-nack" },
};

+static const struct riic_irq_desc riic_rzt2h_irqs[] = {
+ { .res_num = 0, .isr = riic_tend_isr, .name = "riic-tend" },
+ { .res_num = 1, .isr = riic_rdrf_isr, .name = "riic-rdrf" },
+ { .res_num = 2, .isr = riic_tdre_isr, .name = "riic-tdre" },
+ { .res_num = 3, .isr = riic_eei_isr, .name = "riic-eei" },
+};
+
static int riic_i2c_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -643,6 +664,12 @@ static const struct riic_of_data riic_rz_v2h_info = {
.num_irqs = ARRAY_SIZE(riic_irqs),
};

+static const struct riic_of_data riic_rz_t2h_info = {
+ .regs = riic_rz_v2h_regs,
+ .irqs = riic_rzt2h_irqs,
+ .num_irqs = ARRAY_SIZE(riic_rzt2h_irqs),
+};
+
static int riic_i2c_suspend(struct device *dev)
{
struct riic_dev *riic = dev_get_drvdata(dev);
@@ -695,6 +722,7 @@ static const struct dev_pm_ops riic_i2c_pm_ops = {
static const struct of_device_id riic_i2c_dt_ids[] = {
{ .compatible = "renesas,riic-r7s72100", .data = &riic_rz_a1h_info, },
{ .compatible = "renesas,riic-r9a09g057", .data = &riic_rz_v2h_info },
+ { .compatible = "renesas,riic-r9a09g077", .data = &riic_rz_t2h_info },
{ .compatible = "renesas,riic-rz", .data = &riic_rz_a_info },
{ /* Sentinel */ }
};
--
2.49.0