[PATCH 1/5] i2c: stm32f7: fix configuration of the digital filter
From: Alain Volmat <alain.volmat@foss.st.com>
Date: 2021-02-05 08:54:39
Also in:
linux-arm-kernel, linux-i2c, lkml
Subsystem:
i2c subsystem, i2c subsystem host drivers, st stm32 i2c/smbus driver, the rest · Maintainers:
Wolfram Sang, Andi Shyti, Pierre-Yves MORDRET, Alain Volmat, Linus Torvalds
The digital filter related computation are present in the driver
however the programming of the filter within the IP is missing.
The maximum value for the DNF is wrong and should be 15 instead of 16.
Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver")
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
---
drivers/i2c/busses/i2c-stm32f7.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index 9aa8e65b511e..473fbe144b7e 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c@@ -57,6 +57,8 @@ #define STM32F7_I2C_CR1_RXDMAEN BIT(15) #define STM32F7_I2C_CR1_TXDMAEN BIT(14) #define STM32F7_I2C_CR1_ANFOFF BIT(12) +#define STM32F7_I2C_CR1_DNF_MASK GENMASK(11, 8) +#define STM32F7_I2C_CR1_DNF(n) (((n) & 0xf) << 8) #define STM32F7_I2C_CR1_ERRIE BIT(7) #define STM32F7_I2C_CR1_TCIE BIT(6) #define STM32F7_I2C_CR1_STOPIE BIT(5)
@@ -160,7 +162,7 @@ enum { }; #define STM32F7_I2C_DNF_DEFAULT 0 -#define STM32F7_I2C_DNF_MAX 16 +#define STM32F7_I2C_DNF_MAX 15 #define STM32F7_I2C_ANALOG_FILTER_ENABLE 1 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */
@@ -725,6 +727,13 @@ static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev) else stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_ANFOFF); + + /* Program the Digital Filter */ + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_DNF_MASK); + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_DNF(i2c_dev->setup.dnf)); + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_PE); }
--
2.17.1