| Message ID | 20220615191214.826879-1-dinguyen@kernel.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [PATCHv4,1/2] i2c: designware: introduce a custom scl recovery for SoCFPGA platforms | expand |
On Wed, Jun 15, 2022 at 02:12:13PM -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. > > 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(). Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> (yes, assuming stray change goes away) > Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> > --- > 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 >
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);
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@kernel.org> --- 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(-)