From 6bbb14f018d4e7f958bcdc04b92be412601c44f6 Mon Sep 17 00:00:00 2001 From: Patrick Delaunay Date: Tue, 3 Aug 2021 12:05:13 +0200 Subject: i2c: stm32f7: fix configuration of the digital filter 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. Signed-off-by: Patrick Delaunay Signed-off-by: Patrice Chotard Reviewed-by: Patrice Chotard --- drivers/i2c/stm32f7_i2c.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'drivers/i2c/stm32f7_i2c.c') diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c index e71a0e0aa3..7e6c65fadc 100644 --- a/drivers/i2c/stm32f7_i2c.c +++ b/drivers/i2c/stm32f7_i2c.c @@ -45,6 +45,8 @@ struct stm32_i2c_regs { /* STM32 I2C control 1 */ #define STM32_I2C_CR1_ANFOFF BIT(12) +#define STM32_I2C_CR1_DNF_MASK GENMASK(11, 8) +#define STM32_I2C_CR1_DNF(n) (((n) & 0xf) << 8) #define STM32_I2C_CR1_ERRIE BIT(7) #define STM32_I2C_CR1_TCIE BIT(6) #define STM32_I2C_CR1_STOPIE BIT(5) @@ -106,7 +108,7 @@ struct stm32_i2c_regs { #define STM32_I2C_MAX_LEN 0xff #define STM32_I2C_DNF_DEFAULT 0 -#define STM32_I2C_DNF_MAX 16 +#define STM32_I2C_DNF_MAX 15 #define STM32_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ #define STM32_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */ @@ -155,7 +157,7 @@ struct stm32_i2c_spec { * @clock_src: I2C clock source frequency (Hz) * @rise_time: Rise time (ns) * @fall_time: Fall time (ns) - * @dnf: Digital filter coefficient (0-16) + * @dnf: value of digital filter to apply * @analog_filter: Analog filter delay (On/Off) */ struct stm32_i2c_setup { @@ -842,6 +844,10 @@ static int stm32_i2c_hw_config(struct stm32_i2c_priv *i2c_priv) else setbits_le32(®s->cr1, STM32_I2C_CR1_ANFOFF); + /* Program the Digital Filter */ + clrsetbits_le32(®s->cr1, STM32_I2C_CR1_DNF_MASK, + STM32_I2C_CR1_DNF(i2c_priv->setup.dnf)); + setbits_le32(®s->cr1, STM32_I2C_CR1_PE); return 0; -- cgit v1.2.1