i2c: stm32f7: add support for DNF i2c-digital-filter binding
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>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c
index 7e6c65f..2b2dae6 100644
--- a/drivers/i2c/stm32f7_i2c.c
+++ b/drivers/i2c/stm32f7_i2c.c
@@ -107,7 +107,6 @@
#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 @@
* @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 @@
u32 regmap_sreg;
u32 regmap_creg;
u32 regmap_mask;
+ u32 dnf_dt;
};
static const struct stm32_i2c_spec i2c_specs[] = {
@@ -684,6 +685,7 @@
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 @@
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 @@
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 */