| From | Kamal Mostafa <> | Subject | [PATCH 3.19.y-ckt 131/164] i2c: img-scb: Clear line and interrupt status before starting a transfer | Date | Wed, 2 Dec 2015 08:59:42 -0800 |
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3.19.8-ckt11 -stable review patch. If anyone has any objections, please let me know.
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From: Sifan Naeem <sifan.naeem@imgtec.com>
commit 1ed6faedfc9741cca2d97b25ab73902ba7177093 upstream.
Clear line status and all generated interrupts from the interrupt status register before starting a transfer, as we may have unserviced interrupts from previous transfers that might be handled in the context of the new transfer.
Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver") Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com> Acked-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: James Hartley <james.hartley@imgtec.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/i2c/busses/i2c-img-scb.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c index 515cbb4..90ffb07 100644 --- a/drivers/i2c/busses/i2c-img-scb.c +++ b/drivers/i2c/busses/i2c-img-scb.c @@ -1058,6 +1058,15 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, i2c->last_msg = (i == num - 1); reinit_completion(&i2c->msg_complete); + /* + * Clear line status and all interrupts before starting a + * transfer, as we may have unserviced interrupts from + * previous transfers that might be handled in the context + * of the new transfer. + */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0); + img_i2c_writel(i2c, SCB_CLEAR_REG, ~0); + if (atomic) img_i2c_atomic_start(i2c); else if (msg->flags & I2C_M_RD) -- 1.9.1
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