[PATCH 5.11 141/210] I2C: JZ4780: Fix bug for Ingenic X1000.

Greg Kroah-Hartman
2021-04-12T09:43:37Z

From: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>

[ Upstream commit 942bfbecc0281c75db84f744b9b77b0f2396f484 ]

Only send "X1000_I2C_DC_STOP" when last byte, or it will cause
error when I2C write operation which should look like this:

device_addr + w, reg_addr, data;

But without this patch, it looks like this:

device_addr + w, reg_addr, device_addr + w, data;

Fixes: 21575a7a8d4c ("I2C: JZ4780: Add support for the X1000.")
Reported-by: 杨文龙 (Yang Wenlong) <ywltyut@sina.cn>
Tested-by: 杨文龙 (Yang Wenlong) <ywltyut@sina.cn>
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/busses/i2c-jz4780.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-jz4780.c b/drivers/i2c/busses/i2c-jz4780.c
index cb4a25ebb890..2a946c207928 100644
--- a/drivers/i2c/busses/i2c-jz4780.c
+++ b/drivers/i2c/busses/i2c-jz4780.c
@@ -526,8 +526,8 @@ static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id)
i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
data = *i2c->wbuf;
data &= ~JZ4780_I2C_DC_READ;
- if ((!i2c->stop_hold) && (i2c->cdata->version >=
- ID_X1000))
+ if ((i2c->wt_len == 1) && (!i2c->stop_hold) &&
+ (i2c->cdata->version >= ID_X1000))
data |= X1000_I2C_DC_STOP;
jz4780_i2c_writew(i2c, JZ4780_I2C_DC, data);
i2c->wbuf++;
--
2.30.2