[PATCH AUTOSEL 5.9 50/55] i2c: designware: call i2c_dw_read_clear_intrbits_slave() once

Sasha Levin
2020-11-10T04:04:13Z

From: Michael Wu <michael.wu@vatics.com>

[ Upstream commit 66b92313e2ca9208b5f3ebf5d86e9a818299d8fa ]

If some bits were cleared by i2c_dw_read_clear_intrbits_slave() in
i2c_dw_isr_slave() and not handled immediately, those cleared bits would
not be shown again by later i2c_dw_read_clear_intrbits_slave(). They
therefore were forgotten to be handled.

i2c_dw_read_clear_intrbits_slave() should be called once in an ISR and take
its returned state for all later handlings.

Signed-off-by: Michael Wu <michael.wu@vatics.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/busses/i2c-designware-slave.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c
index 44974b53a6268..13de01a0f75f0 100644
--- a/drivers/i2c/busses/i2c-designware-slave.c
+++ b/drivers/i2c/busses/i2c-designware-slave.c
@@ -159,7 +159,6 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
u32 raw_stat, stat, enabled, tmp;
u8 val = 0, slave_activity;

- regmap_read(dev->map, DW_IC_INTR_STAT, &stat);
regmap_read(dev->map, DW_IC_ENABLE, &enabled);
regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat);
regmap_read(dev->map, DW_IC_STATUS, &tmp);
@@ -168,6 +167,7 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave)
return 0;

+ stat = i2c_dw_read_clear_intrbits_slave(dev);
dev_dbg(dev->dev,
"%#x STATUS SLAVE_ACTIVITY=%#x : RAW_INTR_STAT=%#x : INTR_STAT=%#x\n",
enabled, slave_activity, raw_stat, stat);
@@ -188,11 +188,9 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
val);
}
regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);
- stat = i2c_dw_read_clear_intrbits_slave(dev);
} else {
regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);
regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &tmp);
- stat = i2c_dw_read_clear_intrbits_slave(dev);
}
if (!i2c_slave_event(dev->slave,
I2C_SLAVE_READ_REQUESTED,
@@ -207,7 +205,6 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
regmap_read(dev->map, DW_IC_CLR_RX_DONE, &tmp);

i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val);
- stat = i2c_dw_read_clear_intrbits_slave(dev);
return 1;
}

@@ -219,7 +216,6 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
dev_vdbg(dev->dev, "Byte %X acked!", val);
} else {
i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val);
- stat = i2c_dw_read_clear_intrbits_slave(dev);
}

return 1;
@@ -230,7 +226,6 @@ static irqreturn_t i2c_dw_isr_slave(int this_irq, void *dev_id)
struct dw_i2c_dev *dev = dev_id;
int ret;

- i2c_dw_read_clear_intrbits_slave(dev);
ret = i2c_dw_irq_handler_slave(dev);
if (ret > 0)
complete(&dev->cmd_complete);
--
2.27.0