From 95b22bd6dcf198340b0c40a906a463064c215b0c Mon Sep 17 00:00:00 2001 From: Conor Dooley Date: Wed, 26 Oct 2022 08:49:18 +0100 Subject: [PATCH] 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 Signed-off-by: Conor Dooley Reviewed-by: Padmarao Begari Reviewed-by: Heiko Schocher --- drivers/i2c/i2c-microchip.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/i2c-microchip.c b/drivers/i2c/i2c-microchip.c index 12f65d0af7..3a27459386 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 + * Conor Dooley */ #include #include @@ -265,16 +266,27 @@ static int mpfs_i2c_service_handler(struct mpfs_i2c_bus *bus) } 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; } 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 */ @@ -283,7 +295,6 @@ static int mpfs_i2c_service_handler(struct mpfs_i2c_bus *bus) } 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; -- 2.39.5