i2c: gpio: Run deblock sequence on probe

Add deblock dequence for the I2C bus, needed on some devices. This sequence
is issued once, when probing the driver, and is controlled by DT property,
"i2c-gpio,deblock".

Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>

diff --git a/drivers/i2c/i2c-gpio.c b/drivers/i2c/i2c-gpio.c
index 4e8fa214739a4bee0faa963bac3717f5090a9aae..d56540b4621b4acd8939c383f72a2a1288241b65 100644 (file)
--- a/drivers/i2c/i2c-gpio.c
+++ b/drivers/i2c/i2c-gpio.c
@@ -305,6 +305,21 @@ static int i2c_gpio_set_bus_speed(struct udevice *dev, unsigned int speed_hz)
        return 0;
 }
 
+static int i2c_gpio_drv_probe(struct udevice *dev)
+{
+       if (dev_read_bool(dev, "i2c-gpio,deblock")) {
+               /* @200kHz 9 clocks = 44us, 62us is ok */
+               const unsigned int DELAY_ABORT_SEQ = 62;
+               struct i2c_gpio_bus *bus = dev_get_priv(dev);
+
+               return i2c_deblock_gpio_loop(&bus->gpios[PIN_SDA],
+                                            &bus->gpios[PIN_SCL],
+                                            16, 5, DELAY_ABORT_SEQ);
+       }
+
+       return 0;
+}
+
 static int i2c_gpio_ofdata_to_platdata(struct udevice *dev)
 {
        struct i2c_gpio_bus *bus = dev_get_priv(dev);
@@ -341,6 +356,7 @@ U_BOOT_DRIVER(i2c_gpio) = {
        .name   = "i2c-gpio",
        .id     = UCLASS_I2C,
        .of_match = i2c_gpio_ids,
+       .probe  = i2c_gpio_drv_probe,
        .ofdata_to_platdata = i2c_gpio_ofdata_to_platdata,
        .priv_auto_alloc_size = sizeof(struct i2c_gpio_bus),
        .ops    = &i2c_gpio_ops,