i2c: nordic: switch to phandle arrays for pinmux

Deprecate the scl-pin and sda-pin properties in the devicetree.
Provide new scl-gpios and sda-gpios properties instead.

This lets the user specify SCL and SDA like this:

   &i2c0 {
         scl-gpios = <&gpio0 1 0>;
         sda-gpios = <&gpio1 4 0>;
   };

Instead of having to use:

   &i2c0 {
         scl-pin = <1>;
         sda-pin = <36>;
   };

Provide error checking and understandable error messages for invalid
configurations.

Signed-off-by: Martí Bolívar <[email protected]>

drivers/i2c/i2c_nrfx_twi.c

@@ -8,6 +8,7 @@
 #include <drivers/i2c.h>
 #include <dt-bindings/i2c/i2c.h>
 #include <nrfx_twi.h>
+#include <soc.h>
 
 #include <logging/log.h>
 LOG_MODULE_REGISTER(i2c_nrfx_twi, CONFIG_I2C_LOG_LEVEL);
@@ -276,6 +277,14 @@ static int twi_nrfx_pm_control(const struct device *dev,
  BUILD_ASSERT(I2C_FREQUENCY(idx) != \
  I2C_NRFX_TWI_INVALID_FREQUENCY, \
  "Wrong I2C " #idx " frequency setting in dts"); \
+ NRF_DT_PSEL_CHECK_EXACTLY_ONE(I2C(idx), \
+ sda_pin, "sda-pin", \
+ sda_gpios, "sda-gpios"); \
+ NRF_DT_PSEL_CHECK_EXACTLY_ONE(I2C(idx), \
+ scl_pin, "scl-pin", \
+ scl_gpios, "scl-gpios"); \
+ NRF_DT_CHECK_GPIO_CTLR_IS_SOC(I2C(idx), sda_gpios, "sda-gpios"); \
+ NRF_DT_CHECK_GPIO_CTLR_IS_SOC(I2C(idx), scl_gpios, "scl-gpios"); \
  static int twi_##idx##_init(const struct device *dev) \
  { \
  IRQ_CONNECT(DT_IRQN(I2C(idx)), DT_IRQ(I2C(idx), priority), \
@@ -291,8 +300,8 @@ static int twi_nrfx_pm_control(const struct device *dev,
  static const struct i2c_nrfx_twi_config twi_##idx##z_config = { \
  .twi = NRFX_TWI_INSTANCE(idx), \
  .config = { \
- .scl  = DT_PROP(I2C(idx), scl_pin),  \
- .sda  = DT_PROP(I2C(idx), sda_pin),  \
+ .scl = NRF_DT_PSEL(I2C(idx), scl_pin, scl_gpios, 0), \
+ .sda = NRF_DT_PSEL(I2C(idx), sda_pin, sda_gpios, 0), \
  .frequency = I2C_FREQUENCY(idx), \
  } \
  }; \

drivers/i2c/i2c_nrfx_twim.c

@@ -9,6 +9,7 @@
 #include <dt-bindings/i2c/i2c.h>
 #include <nrfx_twim.h>
 #include <sys/util.h>
+#include <soc.h>
 
 #include <logging/log.h>
 LOG_MODULE_REGISTER(i2c_nrfx_twim, CONFIG_I2C_LOG_LEVEL);
@@ -324,6 +325,14 @@ static int twim_nrfx_pm_control(const struct device *dev,
  BUILD_ASSERT(I2C_FREQUENCY(idx) != \
  I2C_NRFX_TWIM_INVALID_FREQUENCY, \
  "Wrong I2C " #idx " frequency setting in dts"); \
+ NRF_DT_PSEL_CHECK_EXACTLY_ONE(I2C(idx), \
+ sda_pin, "sda-pin", \
+ sda_gpios, "sda-gpios"); \
+ NRF_DT_PSEL_CHECK_EXACTLY_ONE(I2C(idx), \
+ scl_pin, "scl-pin", \
+ scl_gpios, "scl-gpios"); \
+ NRF_DT_CHECK_GPIO_CTLR_IS_SOC(I2C(idx), sda_gpios, "sda-gpios"); \
+ NRF_DT_CHECK_GPIO_CTLR_IS_SOC(I2C(idx), scl_gpios, "scl-gpios"); \
  static int twim_##idx##_init(const struct device *dev) \
  { \
  IRQ_CONNECT(DT_IRQN(I2C(idx)), DT_IRQ(I2C(idx), priority), \
@@ -344,8 +353,8 @@ static int twim_nrfx_pm_control(const struct device *dev,
  static const struct i2c_nrfx_twim_config twim_##idx##z_config = { \
  .twim = NRFX_TWIM_INSTANCE(idx), \
  .config = { \
- .scl  = DT_PROP(I2C(idx), scl_pin),  \
- .sda  = DT_PROP(I2C(idx), sda_pin),  \
+ .scl = NRF_DT_PSEL(I2C(idx), scl_pin, scl_gpios, 0), \
+ .sda = NRF_DT_PSEL(I2C(idx), sda_pin, sda_gpios, 0), \
  .frequency = I2C_FREQUENCY(idx), \
  } \
  }; \

dts/bindings/i2c/nordic,nrf-twi-common.yaml

@@ -13,10 +13,36 @@ properties:
  interrupts:
  required: true
 
+ sda-gpios:
+ type: phandle-array
+ required: false
+ description: |
+ The SDA pin to use. The value is "<&gpioX Y flags>".
+ Pin PX.Y will be used for SDA. The "flags" portion currently
+ has no effect, but must be set to zero.
+
+ For example, to use P0.16 for SDA, set:
+
+ sda-gpios = <&gpio0 16 0>;
+
+ To use P1.2 for SDA, set:
+
+ sda-gpios = <&gpio1 2 0>;
+
+ scl-gpios:
+ type: phandle-array
+ required: false
+ description: |
+ The SCL pin to use. The value should be set in the same
+ way as the sda-gpios property.
+
  sda-pin:
  type: int
- required: true
+ required: false
+ deprecated: true
  description: |
+ Deprecated; use sda-gpios instead.
+
  The SDA pin to use.
 
  For pins P0.0 through P0.31, use the pin number. For example,
@@ -31,7 +57,10 @@ properties:
 
  scl-pin:
  type: int
- required: true
+ required: false
+ deprecated: true
  description: |
+ Deprecated; use scl-gpios instead.
+
  The SCL pin to use. The pin numbering scheme is the same as
  the sda-pin property's.