From: Patrick Delaunay patrick.delaunay@foss.st.com
Add the support for the i2c-digital-filter binding, allowing to enable the digital filter via the device-tree and indicate its value in the DT
Signed-off-by: Patrick Delaunay patrick.delaunay@foss.st.com Signed-off-by: Patrice Chotard patrice.chotard@foss.st.com ---
drivers/i2c/stm32f7_i2c.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c index 7e6c65fadc..2b2dae67a3 100644 --- a/drivers/i2c/stm32f7_i2c.c +++ b/drivers/i2c/stm32f7_i2c.c @@ -107,7 +107,6 @@ struct stm32_i2c_regs {
#define STM32_I2C_MAX_LEN 0xff
-#define STM32_I2C_DNF_DEFAULT 0 #define STM32_I2C_DNF_MAX 15
#define STM32_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ @@ -204,6 +203,7 @@ struct stm32_i2c_timings { * @regmap_sreg: register address for setting Fast Mode Plus bits * @regmap_creg: register address for clearing Fast Mode Plus bits * @regmap_mask: mask for Fast Mode Plus bits + * @dnf_dt: value of digital filter requested via dt */ struct stm32_i2c_priv { struct stm32_i2c_regs *regs; @@ -214,6 +214,7 @@ struct stm32_i2c_priv { u32 regmap_sreg; u32 regmap_creg; u32 regmap_mask; + u32 dnf_dt; };
static const struct stm32_i2c_spec i2c_specs[] = { @@ -684,6 +685,7 @@ static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv, const struct stm32_i2c_spec *specs; struct stm32_i2c_timings *v, *_v; struct list_head solutions; + u32 i2cclk = DIV_ROUND_CLOSEST(STM32_NSEC_PER_SEC, setup->clock_src); int ret;
specs = get_specs(setup->speed_freq); @@ -701,6 +703,8 @@ static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv, return -EINVAL; }
+ /* Analog and Digital Filters */ + setup->dnf = DIV_ROUND_CLOSEST(i2c_priv->dnf_dt, i2cclk); if (setup->dnf > STM32_I2C_DNF_MAX) { log_err("DNF out of bound %d/%d\n", setup->dnf, STM32_I2C_DNF_MAX); @@ -923,7 +927,10 @@ static int stm32_of_to_plat(struct udevice *dev) fall_time = dev_read_u32_default(dev, "i2c-scl-falling-time-ns", STM32_I2C_FALL_TIME_DEFAULT);
- i2c_priv->setup.dnf = STM32_I2C_DNF_DEFAULT; + i2c_priv->dnf_dt = dev_read_u32_default(dev, "i2c-digital-filter-width-ns", 0); + if (!dev_read_bool(dev, "i2c-digital-filter")) + i2c_priv->dnf_dt = 0; + i2c_priv->setup.analog_filter = dev_read_bool(dev, "i2c-analog-filter");
/* Optional */