This patch adds the infrastructure required to register non-linear gpio
ranges through gpiolib and the standard GPIO device tree bindings.
Signed-off-by: Christian Ruppert <christian.ruppert@xxxxxxxxxx>
---
Documentation/devicetree/bindings/gpio/gpio.txt | 40 ++++++++++++++-
drivers/gpio/gpiolib-of.c | 63 ++++++++++++++++++++---
drivers/gpio/gpiolib.c | 47 +++++++++++++++++
drivers/pinctrl/core.c | 14 +++++
include/asm-generic/gpio.h | 10 ++++
include/linux/gpio.h | 9 +++
include/linux/pinctrl/pinctrl.h | 3 +
7 files changed, 176 insertions(+), 10 deletions(-)
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index 6cec6ff..0c85bb6 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -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".
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 0dfaf20..e787609 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -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;
+ }
}
}
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 86ef346..b83b7e4 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1320,6 +1320,53 @@ 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
* @pinctrl_name: the dev_name() of the pin controller to map to
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 92f86ab..5ee61a4 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -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
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index bde6469..523f405 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -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)
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 552e3f4..234b32f 100644
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -220,6 +220,15 @@ 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)
{
diff --git a/include/linux/pinctrl/pinctrl.h b/include/linux/pinctrl/pinctrl.h
index 5979147..fefb886 100644
--- a/include/linux/pinctrl/pinctrl.h
+++ b/include/linux/pinctrl/pinctrl.h
@@ -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);
--
1.7.1
--
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