From d1d57e5cf0a8d375cf109483cfd757d98672db4b Mon Sep 17 00:00:00 2001 From: Liu Peibao Date: Wed, 26 Feb 2025 22:49:14 +0900 Subject: [PATCH] i2c: designware: do not hold SCL low when I2C_DYNAMIC_TAR_UPDATE is not set BugLink: https://bugs.launchpad.net/bugs/2100292 commit 8de3e97f3d3d62cd9f3067f073e8ac93261597db upstream. 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 Signed-off-by: Xiaowu Ding Co-developed-by: Angus Chen Signed-off-by: Angus Chen Signed-off-by: Liu Peibao Acked-by: Jarkko Nikula Signed-off-by: Andi Shyti Signed-off-by: Greg Kroah-Hartman Signed-off-by: Koichiro Den Signed-off-by: Stefan Bader --- 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 58562700c85e..ced2fb4aeda8 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -442,7 +442,7 @@ 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; @@ -450,9 +450,11 @@ 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 99d8c6bbc032..5eb130c1d671 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -117,6 +117,7 @@ #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)