Commit 586a87e6 authored by Christian Ruppert's avatar Christian Ruppert Committed by Linus Walleij

pinctrl/gpio: non-linear GPIO ranges accesible from gpiolib

This patch adds the infrastructure required to register non-linear gpio
ranges through gpiolib and the standard GPIO device tree bindings.
Signed-off-by: default avatarChristian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Linus Walleij's avatarLinus Walleij <linus.walleij@linaro.org>
parent c8ce8782
......@@ -87,8 +87,10 @@ controllers. The gpio-ranges property described below represents this, and
contains information structures as follows:
gpio-range-list ::= <single-gpio-range> [gpio-range-list]
single-gpio-range ::=
single-gpio-range ::= <numeric-gpio-range> | <named-gpio-range>
numeric-gpio-range ::=
<pinctrl-phandle> <gpio-base> <pinctrl-base> <count>
named-gpio-range ::= <pinctrl-phandle> <gpio-base> '<0 0>'
gpio-phandle : phandle to pin controller node.
gpio-base : Base GPIO ID in the GPIO controller
pinctrl-base : Base pinctrl pin ID in the pin controller
......@@ -97,6 +99,19 @@ contains information structures as follows:
The "pin controller node" mentioned above must conform to the bindings
described in ../pinctrl/pinctrl-bindings.txt.
In case named gpio ranges are used (ranges with both <pinctrl-base> and
<count> set to 0), the property gpio-ranges-group-names contains one string
for every single-gpio-range in gpio-ranges:
gpiorange-names-list ::= <gpiorange-name> [gpiorange-names-list]
gpiorange-name : Name of the pingroup associated to the GPIO range in
the respective pin controller.
Elements of gpiorange-names-list corresponding to numeric ranges contain
the empty string. Elements of gpiorange-names-list corresponding to named
ranges contain the name of a pin group defined in the respective pin
controller. The number of pins/GPIOs in the range is the number of pins in
that pin group.
Previous versions of this binding required all pin controller nodes that
were referenced by any gpio-ranges property to contain a property named
#gpio-range-cells with value <3>. This requirement is now deprecated.
......@@ -104,7 +119,7 @@ However, that property may still exist in older device trees for
compatibility reasons, and would still be required even in new device
trees that need to be compatible with older software.
Example:
Example 1:
qe_pio_e: gpio-controller@1460 {
#gpio-cells = <2>;
......@@ -117,3 +132,24 @@ Example:
Here, a single GPIO controller has GPIOs 0..9 routed to pin controller
pinctrl1's pins 20..29, and GPIOs 10..19 routed to pin controller pinctrl2's
pins 50..59.
Example 2:
gpio_pio_i: gpio-controller@14B0 {
#gpio-cells = <2>;
compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
reg = <0x1480 0x18>;
gpio-controller;
gpio-ranges = <&pinctrl1 0 20 10>,
<&pinctrl2 10 0 0>,
<&pinctrl1 15 0 10>,
<&pinctrl2 25 0 0>;
gpio-ranges-group-names = "",
"foo",
"",
"bar";
};
Here, three GPIO ranges are defined wrt. two pin controllers. pinctrl1 GPIO
ranges are defined using pin numbers whereas the GPIO ranges wrt. pinctrl2
are named "foo" and "bar".
......@@ -190,10 +190,15 @@ static void of_gpiochip_add_pin_range(struct gpio_chip *chip)
struct of_phandle_args pinspec;
struct pinctrl_dev *pctldev;
int index = 0, ret;
const char *name;
static const char group_names_propname[] = "gpio-ranges-group-names";
struct property *group_names;
if (!np)
return;
group_names = of_find_property(np, group_names_propname, NULL);
for (;; index++) {
ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
index, &pinspec);
......@@ -204,14 +209,56 @@ static void of_gpiochip_add_pin_range(struct gpio_chip *chip)
if (!pctldev)
break;
ret = gpiochip_add_pin_range(chip,
pinctrl_dev_get_devname(pctldev),
pinspec.args[0],
pinspec.args[1],
pinspec.args[2]);
if (ret)
break;
if (pinspec.args[2]) {
if (group_names) {
ret = of_property_read_string_index(np,
group_names_propname,
index, &name);
if (strlen(name)) {
pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n",
np->full_name);
break;
}
}
/* npins != 0: linear range */
ret = gpiochip_add_pin_range(chip,
pinctrl_dev_get_devname(pctldev),
pinspec.args[0],
pinspec.args[1],
pinspec.args[2]);
if (ret)
break;
} else {
/* npins == 0: special range */
if (pinspec.args[1]) {
pr_err("%s: Illegal gpio-range format.\n",
np->full_name);
break;
}
if (!group_names) {
pr_err("%s: GPIO group range requested but no %s property.\n",
np->full_name, group_names_propname);
break;
}
ret = of_property_read_string_index(np,
group_names_propname,
index, &name);
if (ret)
break;
if (!strlen(name)) {
pr_err("%s: Group name of GPIO group range cannot be the empty string.\n",
np->full_name);
break;
}
ret = gpiochip_add_pingroup_range(chip, pctldev,
pinspec.args[0], name);
if (ret)
break;
}
}
}
......
......@@ -1319,6 +1319,53 @@ EXPORT_SYMBOL_GPL(gpiochip_find);
#ifdef CONFIG_PINCTRL
/**
* gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
* @chip: the gpiochip to add the range for
* @pinctrl: the dev_name() of the pin controller to map to
* @gpio_offset: the start offset in the current gpio_chip number space
* @pin_group: name of the pin group inside the pin controller
*/
int gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group)
{
struct gpio_pin_range *pin_range;
int ret;
pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
if (!pin_range) {
pr_err("%s: GPIO chip: failed to allocate pin ranges\n",
chip->label);
return -ENOMEM;
}
/* Use local offset as range ID */
pin_range->range.id = gpio_offset;
pin_range->range.gc = chip;
pin_range->range.name = chip->label;
pin_range->range.base = chip->base + gpio_offset;
pin_range->pctldev = pctldev;
ret = pinctrl_get_group_pins(pctldev, pin_group,
&pin_range->range.pins,
&pin_range->range.npins);
if (ret < 0)
return ret;
pinctrl_add_gpio_range(pctldev, &pin_range->range);
pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PINGRP %s\n",
chip->label, gpio_offset,
gpio_offset + pin_range->range.npins - 1,
pinctrl_dev_get_devname(pctldev), pin_group);
list_add_tail(&pin_range->node, &chip->pin_ranges);
return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);
/**
* gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
* @chip: the gpiochip to add the range for
......
......@@ -462,6 +462,20 @@ struct pinctrl_dev *pinctrl_find_and_add_gpio_range(const char *devname,
}
EXPORT_SYMBOL_GPL(pinctrl_find_and_add_gpio_range);
int pinctrl_get_group_pins(struct pinctrl_dev *pctldev, const char *pin_group,
const unsigned **pins, unsigned *num_pins)
{
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
int gs;
gs = pinctrl_get_group_selector(pctldev, pin_group);
if (gs < 0)
return gs;
return pctlops->get_group_pins(pctldev, gs, pins, num_pins);
}
EXPORT_SYMBOL_GPL(pinctrl_get_group_pins);
/**
* pinctrl_find_gpio_range_from_pin() - locate the GPIO range for a pin
* @pctldev: the pin controller device to look in
......
......@@ -228,6 +228,9 @@ struct gpio_pin_range {
int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
unsigned int gpio_offset, unsigned int pin_offset,
unsigned int npins);
int gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group);
void gpiochip_remove_pin_ranges(struct gpio_chip *chip);
#else
......@@ -239,6 +242,13 @@ gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
{
return 0;
}
static inline int
gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group)
{
return 0;
}
static inline void
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
......
......@@ -80,6 +80,7 @@ static inline int irq_to_gpio(unsigned int irq)
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/bug.h>
#include <linux/pinctrl/pinctrl.h>
struct device;
struct gpio_chip;
......@@ -220,6 +221,15 @@ gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
return -EINVAL;
}
static inline int
gpiochip_add_pingroup_range(struct gpio_chip *chip,
struct pinctrl_dev *pctldev,
unsigned int gpio_offset, const char *pin_group)
{
WARN_ON(1);
return -EINVAL;
}
static inline void
gpiochip_remove_pin_ranges(struct gpio_chip *chip)
{
......
......@@ -144,6 +144,9 @@ extern struct pinctrl_dev *pinctrl_find_and_add_gpio_range(const char *devname,
extern struct pinctrl_gpio_range *
pinctrl_find_gpio_range_from_pin(struct pinctrl_dev *pctldev,
unsigned int pin);
extern int pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
const char *pin_group, const unsigned **pins,
unsigned *num_pins);
#ifdef CONFIG_OF
extern struct pinctrl_dev *of_pinctrl_get(struct device_node *np);
......
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