[PATCH AUTOSEL 5.4 22/35] i2c: iproc: generate stop event for slave writes

[PATCH AUTOSEL 5.4 22/35] i2c: iproc: generate stop event for slave writes

[Sasha Levin]

From: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>

[ Upstream commit 068143a8195fb0fdeea1f3ca430b3db0f6d04a53 ]

When slave status is I2C_SLAVE_RX_END, generate I2C_SLAVE_STOP
event to i2c_client.

Fixes: c245d94ed106 ("i2c: iproc: Add multi byte read-write support for slave mode")
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-bcm-iproc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
index 9ffdffaf6141e..03475f1799730 100644
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -359,6 +359,9 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
 			value = (u8)((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
 			i2c_slave_event(iproc_i2c->slave,
 					I2C_SLAVE_WRITE_RECEIVED, &value);
+			if (rx_status == I2C_SLAVE_RX_END)
+				i2c_slave_event(iproc_i2c->slave,
+						I2C_SLAVE_STOP, &value);
 		}
 	} else if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {
 		/* Master read other than start */
-- 
2.20.1

[PATCH AUTOSEL 5.4 32/35] i2c: aspeed: Avoid i2c interrupt status clear race condition.

[Sasha Levin]

From: ryan_chen <ryan_chen@aspeedtech.com>

[ Upstream commit c926c87b8e36dcc0ea5c2a0a0227ed4f32d0516a ]

In AST2600 there have a slow peripheral bus between CPU and i2c
controller. Therefore GIC i2c interrupt status clear have delay timing,
when CPU issue write clear i2c controller interrupt status. To avoid
this issue, the driver need have read after write clear at i2c ISR.

Fixes: f327c686d3ba ("i2c: aspeed: added driver for Aspeed I2C")
Signed-off-by: ryan_chen <ryan_chen@aspeedtech.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[wsa: added Fixes tag]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-aspeed.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index 7b098ff5f5dd3..dad6e432de89f 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -603,6 +603,7 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
 	/* Ack all interrupts except for Rx done */
 	writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE,
 	       bus->base + ASPEED_I2C_INTR_STS_REG);
+	readl(bus->base + ASPEED_I2C_INTR_STS_REG);
 	irq_remaining = irq_received;
 
 #if IS_ENABLED(CONFIG_I2C_SLAVE)
@@ -645,9 +646,11 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
 			irq_received, irq_handled);
 
 	/* Ack Rx done */
-	if (irq_received & ASPEED_I2CD_INTR_RX_DONE)
+	if (irq_received & ASPEED_I2CD_INTR_RX_DONE) {
 		writel(ASPEED_I2CD_INTR_RX_DONE,
 		       bus->base + ASPEED_I2C_INTR_STS_REG);
+		readl(bus->base + ASPEED_I2C_INTR_STS_REG);
+	}
 	spin_unlock(&bus->lock);
 	return irq_remaining ? IRQ_NONE : IRQ_HANDLED;
 }
-- 
2.20.1