i2c: microchip: fix ack sending logic
"Master receive mode" was not correctly sending ACKs/NACKs in the
interrupt handler. Bring the handling of M_SLAR_ACK, M_RX_DATA_ACKED &
M_RX_DATA_NACKED in line with the Linux driver.
Fixes: 0dc0d1e094 ("i2c: Add Microchip PolarFire SoC I2C driver")
Reported-by: Shravan Chippa <shravan.chippa@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Padmarao Begari <padmarao.begari@microchip.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/drivers/i2c/i2c-microchip.c b/drivers/i2c/i2c-microchip.c
index 12f65d0..3a27459 100644
--- a/drivers/i2c/i2c-microchip.c
+++ b/drivers/i2c/i2c-microchip.c
@@ -2,8 +2,9 @@
/*
* Microchip I2C controller driver
*
- * Copyright (C) 2021 Microchip Technology Inc.
+ * Copyright (C) 2021-2022 Microchip Technology Inc.
* Padmarao Begari <padmarao.begari@microchip.com>
+ * Conor Dooley <conor.dooley@microchip.com>
*/
#include <common.h>
#include <clk.h>
@@ -265,10 +266,18 @@
}
break;
case STATUS_M_SLAR_ACK:
- ctrl = readl(bus->base + MPFS_I2C_CTRL);
- ctrl |= CTRL_AA;
- writel(ctrl, bus->base + MPFS_I2C_CTRL);
- if (bus->msg_len == 0) {
+ if (bus->msg_len > 1u) {
+ ctrl = readl(bus->base + MPFS_I2C_CTRL);
+ ctrl |= CTRL_AA;
+ writel(ctrl, bus->base + MPFS_I2C_CTRL);
+ } else if (bus->msg_len == 1u) {
+ ctrl = readl(bus->base + MPFS_I2C_CTRL);
+ ctrl &= ~CTRL_AA;
+ writel(ctrl, bus->base + MPFS_I2C_CTRL);
+ } else {
+ ctrl = readl(bus->base + MPFS_I2C_CTRL);
+ ctrl |= CTRL_AA;
+ writel(ctrl, bus->base + MPFS_I2C_CTRL);
/* On the last byte to be transmitted, send STOP */
mpfs_i2c_stop(bus);
finish = true;
@@ -276,6 +285,9 @@
break;
case STATUS_M_RX_DATA_ACKED:
mpfs_i2c_empty_rx(bus);
+ break;
+ case STATUS_M_RX_DATA_NACKED:
+ mpfs_i2c_empty_rx(bus);
if (bus->msg_len == 0) {
/* On the last byte to be transmitted, send STOP */
mpfs_i2c_stop(bus);
@@ -283,7 +295,6 @@
}
break;
case STATUS_M_TX_DATA_NACK:
- case STATUS_M_RX_DATA_NACKED:
case STATUS_M_SLAR_NACK:
case STATUS_M_SLAW_NACK:
bus->msg_err = -ENXIO;