From 8de3e97f3d3d62cd9f3067f073e8ac93261597db Mon Sep 17 00:00:00 2001
From: Liu Peibao <loven.liu@jaguarmicro.com>
Date: Fri, 1 Nov 2024 16:12:43 +0800
Subject: [PATCH] i2c: designware: do not hold SCL low when
I2C_DYNAMIC_TAR_UPDATE is not set
When the Tx FIFO is empty and the last command has no STOP bit
set, the master holds SCL low. If I2C_DYNAMIC_TAR_UPDATE is not
set, BIT(13) MST_ON_HOLD of IC_RAW_INTR_STAT is not enabled,
causing the __i2c_dw_disable() timeout. This is quite similar to
commit 2409205acd3c ("i2c: designware: fix __i2c_dw_disable() in
case master is holding SCL low"). Also check BIT(7)
MST_HOLD_TX_FIFO_EMPTY in IC_STATUS, which is available when
IC_STAT_FOR_CLK_STRETCH is set.
Fixes: 2409205acd3c ("i2c: designware: fix __i2c_dw_disable() in case master is holding SCL low")
Co-developed-by: Xiaowu Ding <xiaowu.ding@jaguarmicro.com>
Signed-off-by: Xiaowu Ding <xiaowu.ding@jaguarmicro.com>
Co-developed-by: Angus Chen <angus.chen@jaguarmicro.com>
Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com>
Signed-off-by: Liu Peibao <loven.liu@jaguarmicro.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
---
drivers/i2c/busses/i2c-designware-common.c | 6 ++++--
drivers/i2c/busses/i2c-designware-core.h | 1 +
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index f31d352d98b57..9d88b4fa03e42 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -524,7 +524,7 @@ err_release_lock:
void __i2c_dw_disable(struct dw_i2c_dev *dev)
{
struct i2c_timings *t = &dev->timings;
- unsigned int raw_intr_stats;
+ unsigned int raw_intr_stats, ic_stats;
unsigned int enable;
int timeout = 100;
bool abort_needed;
@@ -532,9 +532,11 @@ void __i2c_dw_disable(struct dw_i2c_dev *dev)
int ret;
regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_intr_stats);
+ regmap_read(dev->map, DW_IC_STATUS, &ic_stats);
regmap_read(dev->map, DW_IC_ENABLE, &enable);
- abort_needed = raw_intr_stats & DW_IC_INTR_MST_ON_HOLD;
+ abort_needed = (raw_intr_stats & DW_IC_INTR_MST_ON_HOLD) ||
+ (ic_stats & DW_IC_STATUS_MASTER_HOLD_TX_FIFO_EMPTY);
if (abort_needed) {
if (!(enable & DW_IC_ENABLE_ENABLE)) {
regmap_write(dev->map, DW_IC_ENABLE, DW_IC_ENABLE_ENABLE);
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 8e8854ec98825..2d32896d06734 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -116,6 +116,7 @@
#define DW_IC_STATUS_RFNE BIT(3)
#define DW_IC_STATUS_MASTER_ACTIVITY BIT(5)
#define DW_IC_STATUS_SLAVE_ACTIVITY BIT(6)
+#define DW_IC_STATUS_MASTER_HOLD_TX_FIFO_EMPTY BIT(7)
#define DW_IC_SDA_HOLD_RX_SHIFT 16
#define DW_IC_SDA_HOLD_RX_MASK GENMASK(23, 16)
--
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