[PATCH v3 1/6] i2c: i2c-stm32f7: Add 10-bit address support

Pierre-Yves MORDRET pierre-yves.mordret at st.com
Wed Apr 11 06:24:53 PDT 2018


This patch adds support for 10-bit device address for STM32F7 I2C

Signed-off-by: M'boumba Cedric Madianga <cedric.madianga at gmail.com>
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret at st.com>
---
  Version history:
     v1:
        * Initial
     v2:
     v3:
---
---
 drivers/i2c/busses/i2c-stm32f7.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index f273e28..ae0d15c 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -65,7 +65,12 @@
 #define STM32F7_I2C_CR2_NACK			BIT(15)
 #define STM32F7_I2C_CR2_STOP			BIT(14)
 #define STM32F7_I2C_CR2_START			BIT(13)
+#define STM32F7_I2C_CR2_HEAD10R			BIT(12)
+#define STM32F7_I2C_CR2_ADD10			BIT(11)
 #define STM32F7_I2C_CR2_RD_WRN			BIT(10)
+#define STM32F7_I2C_CR2_SADD10_MASK		GENMASK(9, 0)
+#define STM32F7_I2C_CR2_SADD10(n)		(((n) & \
+						STM32F7_I2C_CR2_SADD10_MASK))
 #define STM32F7_I2C_CR2_SADD7_MASK		GENMASK(7, 1)
 #define STM32F7_I2C_CR2_SADD7(n)		(((n) & 0x7f) << 1)
 
@@ -176,14 +181,14 @@ struct stm32f7_i2c_timings {
 
 /**
  * struct stm32f7_i2c_msg - client specific data
- * @addr: 8-bit slave addr, including r/w bit
+ * @addr: 8-bit or 10-bit slave addr, including r/w bit
  * @count: number of bytes to be transferred
  * @buf: data buffer
  * @result: result of the transfer
  * @stop: last I2C msg to be sent, i.e. STOP to be generated
  */
 struct stm32f7_i2c_msg {
-	u8 addr;
+	u16 addr;
 	u32 count;
 	u8 *buf;
 	int result;
@@ -629,8 +634,15 @@ static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev,
 		cr2 |= STM32F7_I2C_CR2_RD_WRN;
 
 	/* Set slave address */
-	cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
-	cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
+	cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10);
+	if (msg->flags & I2C_M_TEN) {
+		cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK;
+		cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr);
+		cr2 |= STM32F7_I2C_CR2_ADD10;
+	} else {
+		cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK;
+		cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr);
+	}
 
 	/* Set nb bytes to transfer and reload if needed */
 	cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD);
@@ -798,7 +810,7 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
 
 static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
 {
-	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
 }
 
 static struct i2c_algorithm stm32f7_i2c_algo = {
-- 
2.7.4




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