On Fr, 2024-01-12 at 17:36 +0100, Krzysztof Kozlowski wrote: > From: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > > Some hardware designs with multiple PCA954x devices use a reset GPIO > connected to all the muxes. Support this configuration by making use of > the reset controller framework which can deal with the shared reset > GPIOs. Fall back to the old GPIO descriptor method if the reset > controller framework is not enabled. > > Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > Acked-by: Peter Rosin <peda@xxxxxxxxxx> > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > Link: https://lore.kernel.org/r/20240108041913.7078-1-chris.packham@xxxxxxxxxxxxxxxxxxx > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> > > --- > > If previous patches are fine, then this commit is independent and could > be taken via I2C. > > Cc: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx> > Cc: Bartosz Golaszewski <brgl@xxxxxxxx> > Cc: Sean Anderson <sean.anderson@xxxxxxxx> > --- > drivers/i2c/muxes/i2c-mux-pca954x.c | 46 ++++++++++++++++++++++++----- > 1 file changed, 38 insertions(+), 8 deletions(-) > > diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c > index 2219062104fb..1702e8d49b91 100644 > --- a/drivers/i2c/muxes/i2c-mux-pca954x.c > +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c > @@ -49,6 +49,7 @@ > #include <linux/pm.h> > #include <linux/property.h> > #include <linux/regulator/consumer.h> > +#include <linux/reset.h> > #include <linux/slab.h> > #include <linux/spinlock.h> > #include <dt-bindings/mux/mux.h> > @@ -102,6 +103,9 @@ struct pca954x { > unsigned int irq_mask; > raw_spinlock_t lock; > struct regulator *supply; > + > + struct gpio_desc *reset_gpio; > + struct reset_control *reset_cont; > }; > > /* Provide specs for the MAX735x, PCA954x and PCA984x types we know about */ > @@ -477,6 +481,35 @@ static int pca954x_init(struct i2c_client *client, struct pca954x *data) > return ret; > } > > +static int pca954x_get_reset(struct device *dev, struct pca954x *data) > +{ > + data->reset_cont = devm_reset_control_get_optional_shared(dev, NULL); > + if (IS_ERR(data->reset_cont)) > + return dev_err_probe(dev, PTR_ERR(data->reset_cont), > + "Failed to get reset\n"); > + else if (data->reset_cont) > + return 0; > + > + /* > + * fallback to legacy reset-gpios > + */ devm_reset_control_get_optional_shared() won't return NULL if the "reset-gpios" property is found in the device tree, so the GPIO fallback is dead code. > + data->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); > + if (IS_ERR(data->reset_gpio)) { > + return dev_err_probe(dev, PTR_ERR(data->reset_gpio), > + "Failed to get reset gpio"); > + } > + > + return 0; > +} > + regards Philipp
