+ DT maintainers On Mon, 17 Sep 2018 11:29:49 +0800 Jisheng Zhang <[email protected]> wrote:
> On some platforms, the sda/scl pins are muxed with gpio functions, so > they could be used for recovery. Select the gpio/default pin function > when prepare/unprepare recovery. > > Signed-off-by: Jisheng Zhang <[email protected]> > --- > drivers/i2c/busses/i2c-designware-core.h | 3 +++ > drivers/i2c/busses/i2c-designware-master.c | 22 ++++++++++++++++++++++ > 2 files changed, 25 insertions(+) > > diff --git a/drivers/i2c/busses/i2c-designware-core.h > b/drivers/i2c/busses/i2c-designware-core.h > index e367b1af4ab2..01d5f01691a4 100644 > --- a/drivers/i2c/busses/i2c-designware-core.h > +++ b/drivers/i2c/busses/i2c-designware-core.h > @@ -271,6 +271,9 @@ struct dw_i2c_dev { > int (*init)(struct dw_i2c_dev *dev); > int mode; > struct i2c_bus_recovery_info rinfo; > + struct pinctrl *pinctrl; > + struct pinctrl_state *pins_default; > + struct pinctrl_state *pins_gpio; > }; > > #define ACCESS_SWAP 0x00000001 > diff --git a/drivers/i2c/busses/i2c-designware-master.c > b/drivers/i2c/busses/i2c-designware-master.c > index 94d94b4a9a0d..384d6630366a 100644 > --- a/drivers/i2c/busses/i2c-designware-master.c > +++ b/drivers/i2c/busses/i2c-designware-master.c > @@ -17,6 +17,7 @@ > #include <linux/interrupt.h> > #include <linux/io.h> > #include <linux/module.h> > +#include <linux/pinctrl/consumer.h> > #include <linux/pm_runtime.h> > #include <linux/reset.h> > > @@ -629,6 +630,9 @@ static void i2c_dw_prepare_recovery(struct i2c_adapter > *adap) > { > struct dw_i2c_dev *dev = i2c_get_adapdata(adap); > > + if (dev->pinctrl && dev->pins_gpio) > + pinctrl_select_state(dev->pinctrl, dev->pins_gpio); > + > i2c_dw_disable(dev); > reset_control_assert(dev->rst); > i2c_dw_prepare_clk(dev, false); > @@ -641,6 +645,9 @@ static void i2c_dw_unprepare_recovery(struct i2c_adapter > *adap) > i2c_dw_prepare_clk(dev, true); > reset_control_deassert(dev->rst); > i2c_dw_init_master(dev); > + > + if (dev->pinctrl && dev->pins_default) > + pinctrl_select_state(dev->pinctrl, dev->pins_default); > } > > static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) > @@ -648,6 +655,8 @@ 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; > + struct pinctrl *pinctrl; > + struct pinctrl_state *s; > int r; > > gpio = devm_gpiod_get(dev->dev, "scl", GPIOD_OUT_HIGH); > @@ -664,6 +673,19 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev > *dev) > return PTR_ERR(gpio); > rinfo->sda_gpiod = gpio; > > + pinctrl = devm_pinctrl_get(dev->dev); > + if (PTR_ERR(pinctrl) == -EPROBE_DEFER) > + return -EPROBE_DEFER; > + if (!IS_ERR_OR_NULL(pinctrl)) { > + dev->pinctrl = pinctrl; > + s = pinctrl_lookup_state(pinctrl, PINCTRL_STATE_DEFAULT); > + if (!IS_ERR_OR_NULL(s)) > + dev->pins_default = s; > + s = pinctrl_lookup_state(pinctrl, "gpio"); > + if (!IS_ERR_OR_NULL(s)) > + dev->pins_gpio = s; > + } > + > rinfo->recover_bus = i2c_generic_scl_recovery; > rinfo->prepare_recovery = i2c_dw_prepare_recovery; > rinfo->unprepare_recovery = i2c_dw_unprepare_recovery;
