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| author | Jarkko Nikula <jarkko.nikula@linux.intel.com> | 2024-02-13 14:48:43 +0200 |
|---|---|---|
| committer | Andi Shyti <andi.shyti@kernel.org> | 2024-02-27 01:51:32 +0100 |
| commit | 64b6426a6e97a95c044fd2fff3f0adf7c1edb60c (patch) | |
| tree | d193ac39b1bc39a55ad9ae10512c9245d3a1fd6a /drivers/i2c | |
| parent | 535677e44d57a31e1363529b5ecddb92653d7136 (diff) | |
| download | lwn-64b6426a6e97a95c044fd2fff3f0adf7c1edb60c.tar.gz lwn-64b6426a6e97a95c044fd2fff3f0adf7c1edb60c.zip | |
i2c: designware: Do not enable interrupts shortly in polling mode
I was testing the polling mode txgbe_i2c_dw_xfer_quirk() on a HW where
the i2c-designware has interrupt connected and shared with other device.
I noticed there is a bogus interrupt for each transfer.
Reason for this that both polling mode functions call the
i2c_dw_xfer_init() which enable interrupts then followed by immediate
disable by the same polling mode functions. This is enough to trigger
TX_EMPTY interrupt.
Fix this by introducing a __i2c_dw_write_intr_mask() helper that unmasks
interrupts conditionally and use it in i2c_dw_xfer_init().
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jiawen Wu <jiawenwu@trustnetic.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.h | 8 | ||||
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-master.c | 4 |
2 files changed, 9 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 78c8062a8eb5..8ce6111cdda3 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -352,6 +352,14 @@ static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev) dev->status &= ~STATUS_ACTIVE; } +static inline void __i2c_dw_write_intr_mask(struct dw_i2c_dev *dev, + unsigned int intr_mask) +{ + unsigned int val = dev->flags & ACCESS_POLLING ? 0 : intr_mask; + + regmap_write(dev->map, DW_IC_INTR_MASK, val); +} + void __i2c_dw_disable(struct dw_i2c_dev *dev); extern void i2c_dw_configure_master(struct dw_i2c_dev *dev); diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index e879a0f5cc97..835d82e2c5fe 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -250,7 +250,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) /* Clear and enable interrupts */ regmap_read(dev->map, DW_IC_CLR_INTR, &dummy); - regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_MASTER_MASK); + __i2c_dw_write_intr_mask(dev, DW_IC_INTR_MASTER_MASK); } static int i2c_dw_check_stopbit(struct dw_i2c_dev *dev) @@ -300,7 +300,6 @@ static int amd_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msgs, dev->msgs = msgs; dev->msgs_num = num_msgs; i2c_dw_xfer_init(dev); - regmap_write(dev->map, DW_IC_INTR_MASK, 0); /* Initiate messages read/write transaction */ for (msg_wrt_idx = 0; msg_wrt_idx < num_msgs; msg_wrt_idx++) { @@ -384,7 +383,6 @@ static int txgbe_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msg dev->msgs = msgs; dev->msgs_num = num_msgs; i2c_dw_xfer_init(dev); - regmap_write(dev->map, DW_IC_INTR_MASK, 0); for (msg_idx = 0; msg_idx < num_msgs; msg_idx++) { buf = msgs[msg_idx].buf; |