Browse Source

i2c: Export i2c_deblock_gpio_loop()

Export the i2c_deblock_gpio_loop() so it can be used in other places in
U-Boot. In particular, this is useful in the GPIO I2C driver, which claims
the SDA/SCL GPIOs and thus prevents the i2c_deblock() implementation from
claiming the pins as GPIOs again.

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>
Marek Vasut 4 years ago
parent
commit
7231522a5e
2 changed files with 20 additions and 4 deletions
  1. 4 4
      drivers/i2c/i2c-uclass.c
  2. 16 0
      include/i2c.h

+ 4 - 4
drivers/i2c/i2c-uclass.c

@@ -501,10 +501,10 @@ static int i2c_gpio_get_pin(struct gpio_desc *pin)
 	return dm_gpio_get_value(pin);
 }
 
-static int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin,
-				 struct gpio_desc *scl_pin,
-				 unsigned int scl_count,
-				 unsigned int delay)
+int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin,
+			  struct gpio_desc *scl_pin,
+			  unsigned int scl_count,
+			  unsigned int delay)
 {
 	int ret = 0;
 

+ 16 - 0
include/i2c.h

@@ -330,6 +330,22 @@ uint i2c_get_chip_addr_offset_mask(struct udevice *dev);
  */
 int i2c_deblock(struct udevice *bus);
 
+/**
+ * i2c_deblock_gpio_loop() - recover a bus from an unknown state by toggling SDA/SCL
+ *
+ * This is the inner logic used for toggling I2C SDA/SCL lines as GPIOs
+ * for deblocking the I2C bus.
+ *
+ * @sda_pin:	SDA GPIO
+ * @scl_pin:	SCL GPIO
+ * @scl_count:	Number of SCL clock cycles generated to deblock SDA
+ * @delay:	Delay between SCL clock line changes
+ * @return 0 if OK, -ve on error
+ */
+struct gpio_desc;
+int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin, struct gpio_desc *scl_pin,
+			  unsigned int scl_count, unsigned int delay);
+
 /**
  * struct dm_i2c_ops - driver operations for I2C uclass
  *