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>
---
v4: re-arrange code per Andy Shevchenko's recommendation
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 | 50 ++++++++++++++++++---
drivers/i2c/busses/i2c-designware-platdrv.c | 1 +
3 files changed, 46 insertions(+), 6 deletions(-)
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..6b75a08a1c1f 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -813,10 +813,26 @@ static void i2c_dw_unprepare_recovery(struct i2c_adapter *adap)
i2c_dw_init_master(dev);
}
-static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
+static int i2c_socfpga_scl_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+ bri->prepare_recovery(adap);
+ bri->unprepare_recovery(adap);
+
+ return 0;
+}
+
+static int i2c_dw_init_socfpga_recovery_info(struct dw_i2c_dev *dev,
+ struct i2c_bus_recovery_info *rinfo)
+{
+ rinfo->recover_bus = i2c_socfpga_scl_recovery;
+ return 1;
+}
+
+static int i2c_dw_init_generic_recovery_info(struct dw_i2c_dev *dev,
+ struct i2c_bus_recovery_info *rinfo)
{
- struct i2c_bus_recovery_info *rinfo = &dev->rinfo;
- struct i2c_adapter *adap = &dev->adapter;
struct gpio_desc *gpio;
gpio = devm_gpiod_get_optional(dev->dev, "scl", GPIOD_OUT_HIGH);
@@ -831,16 +847,38 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
rinfo->sda_gpiod = gpio;
rinfo->recover_bus = i2c_generic_scl_recovery;
- rinfo->prepare_recovery = i2c_dw_prepare_recovery;
- rinfo->unprepare_recovery = i2c_dw_unprepare_recovery;
- adap->bus_recovery_info = rinfo;
dev_info(dev->dev, "running with gpio recovery mode! scl%s",
rinfo->sda_gpiod ? ",sda" : "");
+ return 1;
+}
+
+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;
+ int ret;
+
+ switch (dev->flags & MODEL_MASK) {
+ case MODEL_SOCFPGA:
+ ret = i2c_dw_init_socfpga_recovery_info(dev, rinfo);
+ break;
+ default:
+ ret = i2c_dw_init_generic_recovery_info(dev, rinfo);
+ break;
+ }
+ if (ret <= 0)
+ return ret;
+
+ rinfo->prepare_recovery = i2c_dw_prepare_recovery;
+ rinfo->unprepare_recovery = i2c_dw_unprepare_recovery;
+ adap->bus_recovery_info = rinfo;
+
return 0;
}
+
static int amd_i2c_adap_quirk(struct dw_i2c_dev *dev)
{
struct i2c_adapter *adap = &dev->adapter;
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
