/*
* Utility functions for easier handling of OFW GPIO pins.
*
* !!! BEWARE !!!
* GPIOBUS uses children's IVARs, so we cannot use this interface for cross
* tree consumers.
*
*/
static int
gpio_pin_get_by_ofw_impl(device_t consumer, phandle_t cnode,
char *prop_name, int idx, gpio_pin_t *out_pin)
{
phandle_t xref;
pcell_t *cells;
device_t busdev;
struct gpiobus_pin pin;
int ncells, rv;
KASSERT(consumer != NULL && cnode > 0,
("both consumer and cnode required"));
rv = ofw_bus_parse_xref_list_alloc(cnode, prop_name, "#gpio-cells",
idx, &xref, &ncells, &cells);
if (rv != 0)
return (rv);
/* Translate provider to device. */
pin.dev = OF_device_from_xref(xref);
if (pin.dev == NULL) {
OF_prop_free(cells);
return (ENODEV);
}
/* Test if GPIO bus already exist. */
busdev = GPIO_GET_BUS(pin.dev);
if (busdev == NULL) {
OF_prop_free(cells);
return (ENODEV);
}
/* Map GPIO pin. */
rv = gpio_map_gpios(pin.dev, cnode, OF_node_from_xref(xref), ncells,
cells, &pin.pin, &pin.flags);
OF_prop_free(cells);
if (rv != 0)
return (ENXIO);
/* Reserve GPIO pin. */
rv = gpiobus_map_pin(busdev, pin.pin);
if (rv != 0)
return (EBUSY);
*out_pin = malloc(sizeof(struct gpiobus_pin), M_DEVBUF,
M_WAITOK | M_ZERO);
**out_pin = pin;
return (0);
}
static int
gpiobus_parse_pins(struct gpiobus_softc *sc, device_t child, int mask)
{
struct gpiobus_ivar *devi = GPIOBUS_IVAR(child);
int i, npins;
npins = 0;
for (i = 0; i < 32; i++) {
if (mask & (1 << i))
npins++;
}
if (npins == 0) {
device_printf(child, "empty pin mask\n");
return (EINVAL);
}
devi->npins = npins;
if (gpiobus_alloc_ivars(devi) != 0) {
device_printf(child, "cannot allocate device ivars\n");
return (EINVAL);
}
npins = 0;
for (i = 0; i < 32; i++) {
if ((mask & (1 << i)) == 0)
continue;
/* Reserve the GPIO pin. */
if (gpiobus_map_pin(sc->sc_busdev, i) != 0) {
gpiobus_free_ivars(devi);
return (EINVAL);
}
devi->pins[npins++] = i;
/* Use the child name as pin name. */
GPIOBUS_PIN_SETNAME(sc->sc_busdev, i,
device_get_nameunit(child));
}
return (0);
}
static int
ofw_gpiobus_parse_gpios_impl(device_t consumer, phandle_t cnode, char *pname,
struct gpiobus_softc *bussc, struct gpiobus_pin **pins)
{
int gpiocells, i, j, ncells, npins;
pcell_t *gpios;
phandle_t gpio;
ncells = OF_getencprop_alloc(cnode, pname, sizeof(*gpios),
(void **)&gpios);
if (ncells == -1) {
device_printf(consumer,
"Warning: No %s specified in fdt data; "
"device may not function.\n", pname);
return (-1);
}
/*
* The gpio-specifier is controller independent, the first pcell has
* the reference to the GPIO controller phandler.
* Count the number of encoded gpio-specifiers on the first pass.
*/
i = 0;
npins = 0;
while (i < ncells) {
/* Allow NULL specifiers. */
if (gpios[i] == 0) {
npins++;
i++;
continue;
}
gpio = OF_node_from_xref(gpios[i]);
/* If we have bussc, ignore devices from other gpios. */
if (bussc != NULL)
if (ofw_bus_get_node(bussc->sc_dev) != gpio)
return (0);
/*
* Check for gpio-controller property and read the #gpio-cells
* for this GPIO controller.
*/
if (!OF_hasprop(gpio, "gpio-controller") ||
OF_getencprop(gpio, "#gpio-cells", &gpiocells,
sizeof(gpiocells)) < 0) {
device_printf(consumer,
"gpio reference is not a gpio-controller.\n");
OF_prop_free(gpios);
return (-1);
}
if (ncells - i < gpiocells + 1) {
device_printf(consumer,
"%s cells doesn't match #gpio-cells.\n", pname);
return (-1);
}
npins++;
i += gpiocells + 1;
}
if (npins == 0 || pins == NULL) {
if (npins == 0)
device_printf(consumer, "no pin specified in %s.\n",
pname);
OF_prop_free(gpios);
return (npins);
}
*pins = malloc(sizeof(struct gpiobus_pin) * npins, M_DEVBUF,
M_NOWAIT | M_ZERO);
if (*pins == NULL) {
OF_prop_free(gpios);
return (-1);
}
/* Decode the gpio specifier on the second pass. */
i = 0;
j = 0;
while (i < ncells) {
/* Allow NULL specifiers. */
if (gpios[i] == 0) {
j++;
i++;
continue;
}
gpio = OF_node_from_xref(gpios[i]);
/* Read gpio-cells property for this GPIO controller. */
if (OF_getencprop(gpio, "#gpio-cells", &gpiocells,
sizeof(gpiocells)) < 0) {
device_printf(consumer,
"gpio does not have the #gpio-cells property.\n");
goto fail;
}
/* Return the device reference for the GPIO controller. */
(*pins)[j].dev = OF_device_from_xref(gpios[i]);
if ((*pins)[j].dev == NULL) {
device_printf(consumer,
"no device registered for the gpio controller.\n");
goto fail;
}
/*
* If the gpiobus softc is NULL we use the GPIO_GET_BUS() to
* retrieve it. The GPIO_GET_BUS() method is only valid after
* the child is probed and attached.
*/
if (bussc == NULL) {
if (GPIO_GET_BUS((*pins)[j].dev) == NULL) {
device_printf(consumer,
"no gpiobus reference for %s.\n",
device_get_nameunit((*pins)[j].dev));
goto fail;
}
bussc = device_get_softc(GPIO_GET_BUS((*pins)[j].dev));
}
/* Get the GPIO pin number and flags. */
if (gpio_map_gpios((*pins)[j].dev, cnode, gpio, gpiocells,
&gpios[i + 1], &(*pins)[j].pin, &(*pins)[j].flags) != 0) {
device_printf(consumer,
"cannot map the gpios specifier.\n");
goto fail;
}
/* Reserve the GPIO pin. */
if (gpiobus_map_pin(bussc->sc_busdev, (*pins)[j].pin) != 0)
goto fail;
j++;
i += gpiocells + 1;
}
OF_prop_free(gpios);
return (npins);
fail:
OF_prop_free(gpios);
free(*pins, M_DEVBUF);
return (-1);
}
