* [PATCH AUTOSEL 5.2 39/59] i2c: iproc: Fix i2c master read more than 63 bytes
[not found] <20190806213319.19203-1-sashal@kernel.org>
@ 2019-08-06 21:32 ` Sasha Levin
0 siblings, 0 replies; only message in thread
From: Sasha Levin @ 2019-08-06 21:32 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Rayagonda Kokatanur, stable, Ray Jui, Wolfram Sang, Sasha Levin,
linux-i2c
From: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
[ Upstream commit fd01eecdf9591453177d7b06faaabef8c300114a ]
Use SMBUS_MASTER_DATA_READ.MASTER_RD_STATUS bit to check for RX
FIFO empty condition because SMBUS_MASTER_FIFO_CONTROL.MASTER_RX_PKT_COUNT
is not updated for read >= 64 bytes. This fixes the issue when trying to
read from the I2C slave more than 63 bytes.
Fixes: c24b8d574b7c ("i2c: iproc: Extend I2C read up to 255 bytes")
Cc: stable@kernel.org
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/busses/i2c-bcm-iproc.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
index a845b8decac8f..ad1681872e39d 100644
--- a/drivers/i2c/busses/i2c-bcm-iproc.c
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -403,16 +403,18 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
{
struct i2c_msg *msg = iproc_i2c->msg;
+ uint32_t val;
/* Read valid data from RX FIFO */
while (iproc_i2c->rx_bytes < msg->len) {
- if (!((iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET) >> M_FIFO_RX_CNT_SHIFT)
- & M_FIFO_RX_CNT_MASK))
+ val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
+
+ /* rx fifo empty */
+ if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
break;
msg->buf[iproc_i2c->rx_bytes] =
- (iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET) >>
- M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
+ (val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
iproc_i2c->rx_bytes++;
}
}
--
2.20.1
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