The I2C pins on the SoCFPGA platforms do not go through a GPIO module,
thus cannot be recovered by the default method of by doing a GPIO access.
Only a reset of the I2C IP block can a recovery be successful.
The assignment of the recover_bus needs to get done before the call to
devm_gpiod_get_optional(), otherwise, the assignment is not taking place
because of an error after returning from devm_gpiod_get_optional().
Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx>
---
v3: simplify the function
update commit message
v2: remove change to MODEL_MASK
s/i2c_custom_scl_recovery/i2c_socfpga_scl_recovery
---
drivers/i2c/busses/i2c-designware-core.h | 1 +
drivers/i2c/busses/i2c-designware-master.c | 12 ++++++++++++
drivers/i2c/busses/i2c-designware-platdrv.c | 1 +
3 files changed, 14 insertions(+)
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 70b80e710990..7b22ec1d6a96 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -303,6 +303,7 @@ struct dw_i2c_dev {
#define MODEL_MSCC_OCELOT BIT(8)
#define MODEL_BAIKAL_BT1 BIT(9)
#define MODEL_AMD_NAVI_GPU BIT(10)
+#define MODEL_SOCFPGA BIT(11)
#define MODEL_MASK GENMASK(11, 8)
/*
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 44a94b225ed8..502820b812a5 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -813,12 +813,24 @@ static void i2c_dw_unprepare_recovery(struct i2c_adapter *adap)
i2c_dw_init_master(dev);
}
+static int i2c_socfpga_scl_recovery(struct i2c_adapter *adap)
+{
+ i2c_dw_prepare_recovery(adap);
+ i2c_dw_unprepare_recovery(adap);
+ return 0;
+}
+
static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
{
struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
struct i2c_adapter *adap = &dev->adapter;
struct gpio_desc *gpio;
+ if ((dev->flags & MODEL_MASK) == MODEL_SOCFPGA) {
+ rinfo->recover_bus = i2c_socfpga_scl_recovery;
+ adap->bus_recovery_info = rinfo;
+ }
+
gpio = devm_gpiod_get_optional(dev->dev, "scl", GPIOD_OUT_HIGH);
if (IS_ERR_OR_NULL(gpio))
return PTR_ERR_OR_ZERO(gpio);
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 70ade5306e45..b33e015e6732 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -153,6 +153,7 @@ static const struct of_device_id dw_i2c_of_match[] = {
{ .compatible = "snps,designware-i2c", },
{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
{ .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
+ { .compatible = "intel,socfpga-i2c", .data = (void *)MODEL_SOCFPGA },
{},
};
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
--
2.25.1
