On 2019-04-24 14:34, Serge Semin wrote: > Most modern platforms provide a dts with description of the devices > available in the system. It may also include i2c-gpio-mux'es. > Up until now the i2c-mux-gpio driver supported it' dts nodes, but > performed the GPIOs request by means of legacy GPIO API, which by design > and due to being legacy doesn't know anything about of/dtb/fdt/dts stuff. > It means even though the i2c-gpio-mux dts nodes are successfully mapped > to the kernel i2c-mux devices, the GPIOs used for initialization are > requested without OF_GPIO_* flags setup. It causes problems on the > platforms which fully rely on dts and reside, for instance, > i2c-gpio-muxes with active low or open drain GPIOs connected. > > It is fixed by implementing a dedicated method for full dts-based > GPIOs requests. It is mostly similar to the platform one, but > utilizes the gpiod_get_from_of_node() method to request the GPIOs. > > Finally the platform code i2c-gpio-mux devices are also supported. > So the fallback to dtb is performed only if array with GPIOs isn't > detected. > > Signed-off-by: Serge Semin <[email protected]> > --- > drivers/i2c/muxes/i2c-mux-gpio.c | 65 ++++++++++++++++++++++++-------- > 1 file changed, 50 insertions(+), 15 deletions(-) > > diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c > b/drivers/i2c/muxes/i2c-mux-gpio.c > index 317c019e1415..e5e10ba35ad9 100644 > --- a/drivers/i2c/muxes/i2c-mux-gpio.c > +++ b/drivers/i2c/muxes/i2c-mux-gpio.c > @@ -65,8 +65,8 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, > struct device_node *np = pdev->dev.of_node; > struct device_node *adapter_np, *child; > struct i2c_adapter *adapter; > - unsigned *values, *gpios; > - int i = 0, ret; > + unsigned int *values; > + int i = 0; > > if (!np) > return -ENODEV; > @@ -109,24 +109,48 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, > return -EINVAL; > } > > - gpios = devm_kcalloc(&pdev->dev, > - mux->data.n_gpios, sizeof(*mux->data.gpios), > - GFP_KERNEL); > - if (!gpios) { > - dev_err(&pdev->dev, "Cannot allocate gpios array"); > - return -ENOMEM; > - } > + return 0; > +} > + > +static int i2c_mux_gpio_request_dt(struct gpiomux *mux, > + struct platform_device *pdev) > +{ > + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); > + struct device_node *np = pdev->dev.of_node; > + struct i2c_adapter *root; > + struct device *gpio_dev; > + enum gpiod_flags dflags; > + int i, ret; > + > + root = i2c_root_adapter(&muxc->parent->dev); > > for (i = 0; i < mux->data.n_gpios; i++) { > - ret = of_get_named_gpio(np, "mux-gpios", i); > - if (ret < 0) > - return ret; > - gpios[i] = ret; > - } > + if (mux->data.idle & (1 << i)) > + dflags = GPIOD_OUT_HIGH; > + else > + dflags = GPIOD_OUT_LOW; > + > + mux->gpios[i] = gpiod_get_from_of_node(np, "mux-gpios", i, > + dflags, "i2c-mux-gpio"); > + if (IS_ERR(mux->gpios[i])) { > + ret = PTR_ERR(mux->gpios[i]); > + goto err_request_gpio; > + } > > - mux->data.gpios = gpios; > + if (!muxc->mux_locked) > + continue; > + > + gpio_dev = &mux->gpios[i]->gdev->dev; > + muxc->mux_locked = i2c_root_adapter(gpio_dev) == root; > + } > > return 0; > + > +err_request_gpio: > + for (i--; i >= 0; i--) > + gpiod_free(mux->gpios[i]); > + > + return ret; > } > #else > static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, > @@ -134,6 +158,12 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, > { > return -EINVAL; > } > + > +static int i2c_mux_gpio_request_dt(struct gpiomux *mux, > + struct platform_device *pdev) > +{ > + return -EINVAL; > +} > #endif > > static int i2c_mux_gpio_probe_plat(struct gpiomux *mux, > @@ -174,6 +204,9 @@ static int i2c_mux_gpio_request_plat(struct gpiomux *mux, > struct device *gpio_dev; > int i, ret; > > + if (!mux->data.gpios) > + return -EINVAL; > + > root = i2c_root_adapter(&muxc->parent->dev); > > for (i = 0; i < mux->data.n_gpios; i++) { > @@ -267,6 +300,8 @@ static int i2c_mux_gpio_probe(struct platform_device > *pdev) > mux->data.idle = mux->data.values[0]; > > ret = i2c_mux_gpio_request_plat(mux, pdev); > + if (ret) > + ret = i2c_mux_gpio_request_dt(mux, pdev); > if (ret) > goto alloc_failed;
Same pattern as for 2/5; any and all errors from i2c_mux_gpio_request_plat are now lost. Cheers, Peter > >
