path: root/include/asm-generic
diff options
authorShiraz Hashim <shiraz.hashim@st.com>2012-10-27 15:21:36 +0530
committerLinus Walleij <linus.walleij@linaro.org>2012-11-11 19:06:00 +0100
commitf23f1516b6757c326cc638bed8c402c77e2a596e (patch)
treed1d17f111e57038c7ef6df43e79bb969c5844cd2 /include/asm-generic
parent7e10ee68f8ccc62e0934ff02f39ce541f3879844 (diff)
gpiolib: provide provision to register pin ranges
pinctrl subsystem needs gpio chip base to prepare set of gpio pin ranges, which a given pinctrl driver can handle. This is important to handle pinctrl gpio request calls in order to program a given pin properly for gpio operation. As gpio base is allocated dynamically during gpiochip registration, presently there exists no clean way to pass this information to the pinctrl subsystem. After few discussions from [1], it was concluded that may be gpio controller reporting the pin range it supports, is a better way than pinctrl subsystem directly registering it. [1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816 Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com> [Edited documentation a bit] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'include/asm-generic')
1 files changed, 25 insertions, 0 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index a9432fc6b8b..92e5c432421 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -5,6 +5,7 @@
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/of.h>
+#include <linux/pinctrl/pinctrl.h>
@@ -47,6 +48,21 @@ struct seq_file;
struct module;
struct device_node;
+ * struct gpio_pin_range - pin range controlled by a gpio chip
+ * @head: list for maintaining set of pin ranges, used internally
+ * @pctldev: pinctrl device which handles corresponding pins
+ * @range: actual range of pins controlled by a gpio controller
+ */
+struct gpio_pin_range {
+ struct list_head node;
+ struct pinctrl_dev *pctldev;
+ struct pinctrl_gpio_range range;
* struct gpio_chip - abstract a GPIO controller
* @label: for diagnostics
@@ -134,6 +150,15 @@ struct gpio_chip {
int (*of_xlate)(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec, u32 *flags);
+ /*
+ * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally
+ * describe the actual pin range which they serve in an SoC. This
+ * information would be used by pinctrl subsystem to configure
+ * corresponding pins for gpio usage.
+ */
+ struct list_head pin_ranges;
extern const char *gpiochip_is_requested(struct gpio_chip *chip,