From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-at91.c | 32 +++++++++++---------------------
1 file changed, 11 insertions(+), 21 deletions(-)
diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 636fd2efad8850..b3a70e8fc653c5 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -487,30 +487,10 @@ static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num)
if (ret < 0)
goto out;
- /*
- * The hardware can handle at most two messages concatenated by a
- * repeated start via it's internal address feature.
- */
- if (num > 2) {
- dev_err(dev->dev,
- "cannot handle more than two concatenated messages.\n");
- ret = 0;
- goto out;
- } else if (num == 2) {
+ if (num == 2) {
int internal_address = 0;
int i;
- if (msg->flags & I2C_M_RD) {
- dev_err(dev->dev, "first transfer must be write.\n");
- ret = -EINVAL;
- goto out;
- }
- if (msg->len > 3) {
- dev_err(dev->dev, "first message size must be <= 3.\n");
- ret = -EINVAL;
- goto out;
- }
-
/* 1st msg is put into the internal address, start with 2nd */
m_start = &msg[1];
for (i = 0; i < msg->len; ++i) {
@@ -540,6 +520,15 @@ out:
return ret;
}
+/*
+ * The hardware can handle at most two messages concatenated by a
+ * repeated start via it's internal address feature.
+ */
+static struct i2c_adapter_quirks at91_twi_quirks = {
+ .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR,
+ .max_comb_1st_msg_len = 3,
+};
+
static u32 at91_twi_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
@@ -777,6 +766,7 @@ static int at91_twi_probe(struct platform_device *pdev)
dev->adapter.owner = THIS_MODULE;
dev->adapter.class = I2C_CLASS_DEPRECATED;
dev->adapter.algo = &at91_twi_algorithm;
+ dev->adapter.quirks = &at91_twi_quirks;
dev->adapter.dev.parent = dev->dev;
dev->adapter.nr = pdev->id;
dev->adapter.timeout = AT91_I2C_TIMEOUT;
--
2.1.4
