2022-05-18 20:25:37

by Dinh Nguyen

Subject: [PATCH 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms

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.

Signed-off-by: Dinh Nguyen <[email protected]>
---
drivers/i2c/busses/i2c-designware-core.h | 3 ++-
drivers/i2c/busses/i2c-designware-master.c | 19 +++++++++++++++++--
drivers/i2c/busses/i2c-designware-platdrv.c | 2 ++
3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 70b80e710990..4e997e381fb6 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -303,7 +303,8 @@ 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_MASK GENMASK(11, 8)
+#define MODEL_SOCFPGA BIT(11)
+#define MODEL_MASK GENMASK(12, 8)

/*
* Enable UCSI interrupt by writing 0xd at register
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 44a94b225ed8..333ad17b967d 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -813,12 +813,29 @@ static void i2c_dw_unprepare_recovery(struct i2c_adapter *adap)
i2c_dw_init_master(dev);
}

+static int i2c_custom_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;

+ switch (dev->flags & MODEL_MASK) {
+ case MODEL_SOCFPGA:
+ rinfo->recover_bus = i2c_custom_scl_recovery;
+ break;
+ default:
+ rinfo->recover_bus = i2c_generic_scl_recovery;
+ break;
+ }
+ 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);
@@ -830,10 +847,8 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
return PTR_ERR(gpio);
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" : "");
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 70ade5306e45..92dfe3456ca7 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -153,6 +153,8 @@ 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

2022-05-19 15:33:18

by Dinh Nguyen

Subject: Re: [PATCH 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms

On 5/19/22 05:20, Andy Shevchenko wrote:
> On Wed, May 18, 2022 at 03:22:16PM -0500, Dinh Nguyen wrote:
>> 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.
>
> ...
>
>> #define MODEL_BAIKAL_BT1 BIT(9)
>> #define MODEL_AMD_NAVI_GPU BIT(10)
>> +#define MODEL_SOCFPGA BIT(11)
>
> ...
>
>> -#define MODEL_MASK GENMASK(11, 8)
>
>> +#define MODEL_MASK GENMASK(12, 8)
>
> Why this change is made?

Sorry, mistake here..will remove.

>
> ...
>
>> + switch (dev->flags & MODEL_MASK) {
>> + case MODEL_SOCFPGA:
>> + rinfo->recover_bus = i2c_custom_scl_recovery;
>
> _custom_ is too broad, use exact name, i.e.
>
> i2c_socfpga_scl_recovery
>

Ok

>> + break;
>> + default:
>> + rinfo->recover_bus = i2c_generic_scl_recovery;
>> + break;
>> + }
>
> ...
>
>> + { .compatible = "intel,socfpga-i2c", .data = (void *)MODEL_SOCFPGA },
>
>> +
>
> Stray change.

Will fix...

Thanks for the review!

Dinh
>

2022-05-21 14:15:25

by Andy Shevchenko

Subject: Re: [PATCH 1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms

On Wed, May 18, 2022 at 03:22:16PM -0500, Dinh Nguyen wrote:
> 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.

...

> #define MODEL_BAIKAL_BT1 BIT(9)
> #define MODEL_AMD_NAVI_GPU BIT(10)
> +#define MODEL_SOCFPGA BIT(11)

...

> -#define MODEL_MASK GENMASK(11, 8)

> +#define MODEL_MASK GENMASK(12, 8)

Why this change is made?

...

> + switch (dev->flags & MODEL_MASK) {
> + case MODEL_SOCFPGA:
> + rinfo->recover_bus = i2c_custom_scl_recovery;

_custom_ is too broad, use exact name, i.e.

i2c_socfpga_scl_recovery

> + break;
> + default:
> + rinfo->recover_bus = i2c_generic_scl_recovery;
> + break;
> + }

...

> + { .compatible = "intel,socfpga-i2c", .data = (void *)MODEL_SOCFPGA },

> +

Stray change.

--
With Best Regards,
Andy Shevchenko