diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt index c8fd136eac83..6d23fa84ee47 100644 --- a/Documentation/pinctrl.txt +++ b/Documentation/pinctrl.txt @@ -7,12 +7,9 @@ This subsystem deals with: - Multiplexing of pins, pads, fingers (etc) see below for details -The intention is to also deal with: - -- Software-controlled biasing and driving mode specific pins, such as - pull-up/down, open drain etc, load capacitance configuration when controlled - by software, etc. - +- Configuration of pins, pads, fingers (etc), such as software-controlled + biasing and driving mode specific pins, such as pull-up/down, open drain, + load capacitance etc. Top-level interface =================== @@ -88,6 +85,11 @@ int __init foo_probe(void) pr_err("could not register foo pin driver\n"); } +To enable the pinctrl subsystem and the subgroups for PINMUX and PINCONF and +selected drivers, you need to select them from your machine's Kconfig entry, +since these are so tightly integrated with the machines they are used on. +See for example arch/arm/mach-u300/Kconfig for an example. + Pins usually have fancier names than this. You can find these in the dataheet for your chip. Notice that the core pinctrl.h file provides a fancy macro called PINCTRL_PIN() to create the struct entries. As you can see I enumerated @@ -193,6 +195,88 @@ structure, for example specific register ranges associated with each group and so on. +Pin configuration +================= + +Pins can sometimes be software-configured in an various ways, mostly related +to their electronic properties when used as inputs or outputs. For example you +may be able to make an output pin high impedance, or "tristate" meaning it is +effectively disconnected. You may be able to connect an input pin to VDD or GND +using a certain resistor value - pull up and pull down - so that the pin has a +stable value when nothing is driving the rail it is connected to, or when it's +unconnected. + +For example, a platform may do this: + +ret = pin_config_set(dev, "FOO_GPIO_PIN", PLATFORM_X_PULL_UP); + +To pull up a pin to VDD. The pin configuration driver implements callbacks for +changing pin configuration in the pin controller ops like this: + +#include +#include +#include "platform_x_pindefs.h" + +int foo_pin_config_get(struct pinctrl_dev *pctldev, + unsigned offset, + unsigned long *config) +{ + struct my_conftype conf; + + ... Find setting for pin @ offset ... + + *config = (unsigned long) conf; +} + +int foo_pin_config_set(struct pinctrl_dev *pctldev, + unsigned offset, + unsigned long config) +{ + struct my_conftype *conf = (struct my_conftype *) config; + + switch (conf) { + case PLATFORM_X_PULL_UP: + ... + } + } +} + +int foo_pin_config_group_get (struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long *config) +{ + ... +} + +int foo_pin_config_group_set (struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long config) +{ + ... +} + +static struct pinconf_ops foo_pconf_ops = { + .pin_config_get = foo_pin_config_get, + .pin_config_set = foo_pin_config_set, + .pin_config_group_get = foo_pin_config_group_get, + .pin_config_group_set = foo_pin_config_group_set, +}; + +/* Pin config operations are handled by some pin controller */ +static struct pinctrl_desc foo_desc = { + ... + .confops = &foo_pconf_ops, +}; + +Since some controllers have special logic for handling entire groups of pins +they can exploit the special whole-group pin control function. The +pin_config_group_set() callback is allowed to return the error code -EAGAIN, +for groups it does not want to handle, or if it just wants to do some +group-level handling and then fall through to iterate over all pins, in which +case each individual pin will be treated by separate pin_config_set() calls as +well. + + Interaction with the GPIO subsystem =================================== diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig index e963da41e948..c63c72102989 100644 --- a/drivers/pinctrl/Kconfig +++ b/drivers/pinctrl/Kconfig @@ -12,7 +12,10 @@ menu "Pin controllers" depends on PINCTRL config PINMUX - bool "Support pinmux controllers" + bool "Support pin multiplexing controllers" + +config PINCONF + bool "Support pin configuration controllers" config DEBUG_PINCTRL bool "Debug PINCTRL calls" diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile index 5f3e4d65465a..c046f78dd7f7 100644 --- a/drivers/pinctrl/Makefile +++ b/drivers/pinctrl/Makefile @@ -4,6 +4,7 @@ ccflags-$(CONFIG_DEBUG_PINCTRL) += -DDEBUG obj-$(CONFIG_PINCTRL) += core.o obj-$(CONFIG_PINMUX) += pinmux.o +obj-$(CONFIG_PINCONF) += pinconf.o obj-$(CONFIG_PINMUX_SIRF) += pinmux-sirf.o obj-$(CONFIG_PINMUX_U300) += pinmux-u300.o obj-$(CONFIG_PINCTRL_COH901) += pinctrl-coh901.o diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 4955a68d618f..034b1ad38b32 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -28,6 +28,7 @@ #include #include "core.h" #include "pinmux.h" +#include "pinconf.h" /* Global list of pin control devices */ static DEFINE_MUTEX(pinctrldev_list_mutex); @@ -100,6 +101,30 @@ struct pin_desc *pin_desc_get(struct pinctrl_dev *pctldev, unsigned int pin) return pindesc; } +/** + * pin_get_from_name() - look up a pin number from a name + * @pctldev: the pin control device to lookup the pin on + * @name: the name of the pin to look up + */ +int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name) +{ + unsigned pin; + + /* The highest pin number need to be included in the loop, thus <= */ + for (pin = 0; pin <= pctldev->desc->maxpin; pin++) { + struct pin_desc *desc; + + desc = pin_desc_get(pctldev, pin); + /* Pin space may be sparse */ + if (desc == NULL) + continue; + if (desc->name && !strcmp(name, desc->name)) + return pin; + } + + return -EINVAL; +} + /** * pin_is_valid() - check if pin exists on controller * @pctldev: the pin control device to check the pin on @@ -160,6 +185,7 @@ static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev, pindesc = kzalloc(sizeof(*pindesc), GFP_KERNEL); if (pindesc == NULL) return -ENOMEM; + spin_lock_init(&pindesc->lock); /* Set owner */ @@ -409,11 +435,15 @@ static int pinctrl_devices_show(struct seq_file *s, void *what) { struct pinctrl_dev *pctldev; - seq_puts(s, "name [pinmux]\n"); + seq_puts(s, "name [pinmux] [pinconf]\n"); mutex_lock(&pinctrldev_list_mutex); list_for_each_entry(pctldev, &pinctrldev_list, node) { seq_printf(s, "%s ", pctldev->desc->name); if (pctldev->desc->pmxops) + seq_puts(s, "yes "); + else + seq_puts(s, "no "); + if (pctldev->desc->confops) seq_puts(s, "yes"); else seq_puts(s, "no"); @@ -492,6 +522,7 @@ static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev) debugfs_create_file("gpio-ranges", S_IFREG | S_IRUGO, device_root, pctldev, &pinctrl_gpioranges_ops); pinmux_init_device_debugfs(device_root, pctldev); + pinconf_init_device_debugfs(device_root, pctldev); } static void pinctrl_init_debugfs(void) @@ -548,6 +579,16 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc, } } + /* If we're implementing pinconfig, check the ops for sanity */ + if (pctldesc->confops) { + ret = pinconf_check_ops(pctldesc->confops); + if (ret) { + pr_err("%s pin config ops lacks necessary functions\n", + pctldesc->name); + return NULL; + } + } + pctldev = kzalloc(sizeof(struct pinctrl_dev), GFP_KERNEL); if (pctldev == NULL) return NULL; diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h index 74dee439dcf0..3f5b911acf18 100644 --- a/drivers/pinctrl/core.h +++ b/drivers/pinctrl/core.h @@ -9,6 +9,10 @@ * License terms: GNU General Public License (GPL) version 2 */ +#include + +struct pinctrl_gpio_range; + /** * struct pinctrl_dev - pin control class device * @node: node to include this pin controller in the global pin controller list @@ -66,6 +70,7 @@ struct pin_desc { struct pinctrl_dev *get_pinctrl_dev_from_dev(struct device *dev, const char *dev_name); struct pin_desc *pin_desc_get(struct pinctrl_dev *pctldev, unsigned int pin); +int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name); int pinctrl_get_device_gpio_range(unsigned gpio, struct pinctrl_dev **outdev, struct pinctrl_gpio_range **outrange); diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c new file mode 100644 index 000000000000..9195eefe258a --- /dev/null +++ b/drivers/pinctrl/pinconf.c @@ -0,0 +1,302 @@ +/* + * Core driver for the pin config portions of the pin control subsystem + * + * Copyright (C) 2011 ST-Ericsson SA + * Written on behalf of Linaro for ST-Ericsson + * + * Author: Linus Walleij + * + * License terms: GNU General Public License (GPL) version 2 + */ +#define pr_fmt(fmt) "pinconfig core: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "core.h" +#include "pinconf.h" + +int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin, + unsigned long *config) +{ + const struct pinconf_ops *ops = pctldev->desc->confops; + + if (!ops || !ops->pin_config_get) { + dev_err(&pctldev->dev, "cannot get pin configuration, missing " + "pin_config_get() function in driver\n"); + return -EINVAL; + } + + return ops->pin_config_get(pctldev, pin, config); +} + +/** + * pin_config_get() - get the configuration of a single pin parameter + * @pctldev: pin controller device for this pin + * @name: name of the pin to get the config for + * @config: the config pointed to by this argument will be filled in with the + * current pin state, it can be used directly by drivers as a numeral, or + * it can be dereferenced to any struct. + */ +int pin_config_get(struct pinctrl_dev *pctldev, const char *name, + unsigned long *config) +{ + int pin; + + pin = pin_get_from_name(pctldev, name); + if (pin < 0) + return pin; + + return pin_config_get_for_pin(pctldev, pin, config); +} +EXPORT_SYMBOL(pin_config_get); + +int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin, + unsigned long config) +{ + const struct pinconf_ops *ops = pctldev->desc->confops; + int ret; + + if (!ops || !ops->pin_config_set) { + dev_err(&pctldev->dev, "cannot configure pin, missing " + "config function in driver\n"); + return -EINVAL; + } + + ret = ops->pin_config_set(pctldev, pin, config); + if (ret) { + dev_err(&pctldev->dev, + "unable to set pin configuration on pin %d\n", pin); + return ret; + } + + return 0; +} + +/** + * pin_config_set() - set the configuration of a single pin parameter + * @pctldev: pin controller device for this pin + * @name: name of the pin to set the config for + * @config: the config in this argument will contain the desired pin state, it + * can be used directly by drivers as a numeral, or it can be dereferenced + * to any struct. + */ +int pin_config_set(struct pinctrl_dev *pctldev, const char *name, + unsigned long config) +{ + int pin; + + pin = pin_get_from_name(pctldev, name); + if (pin < 0) + return pin; + + return pin_config_set_for_pin(pctldev, pin, config); +} +EXPORT_SYMBOL(pin_config_set); + +int pin_config_group_get(struct pinctrl_dev *pctldev, const char *pin_group, + unsigned long *config) +{ + const struct pinconf_ops *ops = pctldev->desc->confops; + int selector; + + if (!ops || !ops->pin_config_group_get) { + dev_err(&pctldev->dev, "cannot get configuration for pin " + "group, missing group config get function in " + "driver\n"); + return -EINVAL; + } + + selector = pinctrl_get_group_selector(pctldev, pin_group); + if (selector < 0) + return selector; + + return ops->pin_config_group_get(pctldev, selector, config); +} +EXPORT_SYMBOL(pin_config_group_get); + + +int pin_config_group_set(struct pinctrl_dev *pctldev, const char *pin_group, + unsigned long config) +{ + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + const struct pinconf_ops *ops = pctldev->desc->confops; + int selector; + const unsigned *pins; + unsigned num_pins; + int ret; + int i; + + if (!ops || (!ops->pin_config_group_set && !ops->pin_config_set)) { + dev_err(&pctldev->dev, "cannot configure pin group, missing " + "config function in driver\n"); + return -EINVAL; + } + + selector = pinctrl_get_group_selector(pctldev, pin_group); + if (selector < 0) + return selector; + + ret = pctlops->get_group_pins(pctldev, selector, &pins, &num_pins); + if (ret) { + dev_err(&pctldev->dev, "cannot configure pin group, error " + "getting pins\n"); + return ret; + } + + /* + * If the pin controller supports handling entire groups we use that + * capability. + */ + if (ops->pin_config_group_set) { + ret = ops->pin_config_group_set(pctldev, selector, config); + /* + * If the pin controller prefer that a certain group be handled + * pin-by-pin as well, it returns -EAGAIN. + */ + if (ret != -EAGAIN) + return ret; + } + + /* + * If the controller cannot handle entire groups, we configure each pin + * individually. + */ + if (!ops->pin_config_set) + return 0; + + for (i = 0; i < num_pins; i++) { + ret = ops->pin_config_set(pctldev, pins[i], config); + if (ret < 0) + return ret; + } + + return 0; +} +EXPORT_SYMBOL(pin_config_group_set); + +int pinconf_check_ops(const struct pinconf_ops *ops) +{ + /* We must be able to read out pin status */ + if (!ops->pin_config_get && !ops->pin_config_group_get) + return -EINVAL; + /* We have to be able to config the pins in SOME way */ + if (!ops->pin_config_set && !ops->pin_config_group_set) + return -EINVAL; + return 0; +} + +#ifdef CONFIG_DEBUG_FS + +static void pinconf_dump_pin(struct pinctrl_dev *pctldev, + struct seq_file *s, int pin) +{ + const struct pinconf_ops *ops = pctldev->desc->confops; + + if (ops && ops->pin_config_dbg_show) + ops->pin_config_dbg_show(pctldev, s, pin); +} + +static int pinconf_pins_show(struct seq_file *s, void *what) +{ + struct pinctrl_dev *pctldev = s->private; + unsigned pin; + + seq_puts(s, "Pin config settings per pin\n"); + seq_puts(s, "Format: pin (name): pinmux setting array\n"); + + /* The highest pin number need to be included in the loop, thus <= */ + for (pin = 0; pin <= pctldev->desc->maxpin; pin++) { + struct pin_desc *desc; + + desc = pin_desc_get(pctldev, pin); + /* Pin space may be sparse */ + if (desc == NULL) + continue; + + seq_printf(s, "pin %d (%s):", pin, + desc->name ? desc->name : "unnamed"); + + pinconf_dump_pin(pctldev, s, pin); + + seq_printf(s, "\n"); + } + + return 0; +} + +static void pinconf_dump_group(struct pinctrl_dev *pctldev, + struct seq_file *s, unsigned selector, + const char *gname) +{ + const struct pinconf_ops *ops = pctldev->desc->confops; + + if (ops && ops->pin_config_group_dbg_show) + ops->pin_config_group_dbg_show(pctldev, s, selector); +} + +static int pinconf_groups_show(struct seq_file *s, void *what) +{ + struct pinctrl_dev *pctldev = s->private; + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + const struct pinconf_ops *ops = pctldev->desc->confops; + unsigned selector = 0; + + if (!ops || !ops->pin_config_group_get) + return 0; + + seq_puts(s, "Pin config settings per pin group\n"); + seq_puts(s, "Format: group (name): pinmux setting array\n"); + + while (pctlops->list_groups(pctldev, selector) >= 0) { + const char *gname = pctlops->get_group_name(pctldev, selector); + + seq_printf(s, "%u (%s):", selector, gname); + pinconf_dump_group(pctldev, s, selector, gname); + selector++; + } + + return 0; +} + +static int pinconf_pins_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinconf_pins_show, inode->i_private); +} + +static int pinconf_groups_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinconf_groups_show, inode->i_private); +} + +static const struct file_operations pinconf_pins_ops = { + .open = pinconf_pins_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations pinconf_groups_ops = { + .open = pinconf_groups_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +void pinconf_init_device_debugfs(struct dentry *devroot, + struct pinctrl_dev *pctldev) +{ + debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO, + devroot, pctldev, &pinconf_pins_ops); + debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO, + devroot, pctldev, &pinconf_groups_ops); +} + +#endif diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h new file mode 100644 index 000000000000..e7dc6165032a --- /dev/null +++ b/drivers/pinctrl/pinconf.h @@ -0,0 +1,36 @@ +/* + * Internal interface between the core pin control system and the + * pin config portions + * + * Copyright (C) 2011 ST-Ericsson SA + * Written on behalf of Linaro for ST-Ericsson + * Based on bits of regulator core, gpio core and clk core + * + * Author: Linus Walleij + * + * License terms: GNU General Public License (GPL) version 2 + */ + +#ifdef CONFIG_PINCONF + +int pinconf_check_ops(const struct pinconf_ops *ops); +void pinconf_init_device_debugfs(struct dentry *devroot, + struct pinctrl_dev *pctldev); +int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin, + unsigned long *config); +int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin, + unsigned long config); + +#else + +static inline int pinconf_check_ops(const struct pinconf_ops *ops) +{ + return 0; +} + +static inline void pinconf_init_device_debugfs(struct dentry *devroot, + struct pinctrl_dev *pctldev) +{ +} + +#endif diff --git a/include/linux/pinctrl/pinconf.h b/include/linux/pinctrl/pinconf.h new file mode 100644 index 000000000000..d5b72e6e261d --- /dev/null +++ b/include/linux/pinctrl/pinconf.h @@ -0,0 +1,96 @@ +/* + * Interface the pinconfig portions of the pinctrl subsystem + * + * Copyright (C) 2011 ST-Ericsson SA + * Written on behalf of Linaro for ST-Ericsson + * This interface is used in the core to keep track of pins. + * + * Author: Linus Walleij + * + * License terms: GNU General Public License (GPL) version 2 + */ +#ifndef __LINUX_PINCTRL_PINCONF_H +#define __LINUX_PINCTRL_PINCONF_H + +#ifdef CONFIG_PINCONF + +struct pinctrl_dev; + +/** + * struct pinconf_ops - pin config operations, to be implemented by + * pin configuration capable drivers. + * @pin_config_get: get the config of a certain pin, if the requested config + * is not available on this controller this should return -ENOTSUPP + * and if it is available but disabled it should return -EINVAL + * @pin_config_get: get the config of a certain pin + * @pin_config_set: configure an individual pin + * @pin_config_group_get: get configurations for an entire pin group + * @pin_config_group_set: configure all pins in a group + * @pin_config_dbg_show: optional debugfs display hook that will provide + * per-device info for a certain pin in debugfs + * @pin_config_group_dbg_show: optional debugfs display hook that will provide + * per-device info for a certain group in debugfs + */ +struct pinconf_ops { + int (*pin_config_get) (struct pinctrl_dev *pctldev, + unsigned pin, + unsigned long *config); + int (*pin_config_set) (struct pinctrl_dev *pctldev, + unsigned pin, + unsigned long config); + int (*pin_config_group_get) (struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long *config); + int (*pin_config_group_set) (struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long config); + void (*pin_config_dbg_show) (struct pinctrl_dev *pctldev, + struct seq_file *s, + unsigned offset); + void (*pin_config_group_dbg_show) (struct pinctrl_dev *pctldev, + struct seq_file *s, + unsigned selector); +}; + +extern int pin_config_get(struct pinctrl_dev *pctldev, const char *name, + unsigned long *config); +extern int pin_config_set(struct pinctrl_dev *pctldev, const char *name, + unsigned long config); +extern int pin_config_group_get(struct pinctrl_dev *pctldev, + const char *pin_group, + unsigned long *config); +extern int pin_config_group_set(struct pinctrl_dev *pctldev, + const char *pin_group, + unsigned long config); + +#else + +static inline int pin_config_get(struct pinctrl_dev *pctldev, const char *name, + unsigned long *config) +{ + return 0; +} + +static inline int pin_config_set(struct pinctrl_dev *pctldev, const char *name, + unsigned long config) +{ + return 0; +} + +static inline int pin_config_group_get(struct pinctrl_dev *pctldev, + const char *pin_group, + unsigned long *config) +{ + return 0; +} + +static inline int pin_config_group_set(struct pinctrl_dev *pctldev, + const char *pin_group, + unsigned long config) +{ + return 0; +} + +#endif + +#endif /* __LINUX_PINCTRL_PINCONF_H */ diff --git a/include/linux/pinctrl/pinctrl.h b/include/linux/pinctrl/pinctrl.h index f17fac4b51f1..9809a94f151b 100644 --- a/include/linux/pinctrl/pinctrl.h +++ b/include/linux/pinctrl/pinctrl.h @@ -21,6 +21,7 @@ struct pinctrl_dev; struct pinmux_ops; +struct pinconf_ops; struct gpio_chip; /** @@ -97,7 +98,9 @@ struct pinctrl_ops { * but may be equal to npins if you have no holes in the pin range. * @pctlops: pin control operation vtable, to support global concepts like * grouping of pins, this is optional. - * @pmxops: pinmux operation vtable, if you support pinmuxing in your driver + * @pmxops: pinmux operations vtable, if you support pinmuxing in your driver + * @confops: pin config operations vtable, if you support pin configuration in + * your driver * @owner: module providing the pin controller, used for refcounting */ struct pinctrl_desc { @@ -107,6 +110,7 @@ struct pinctrl_desc { unsigned int maxpin; struct pinctrl_ops *pctlops; struct pinmux_ops *pmxops; + struct pinconf_ops *confops; struct module *owner; }; @@ -125,7 +129,7 @@ extern void *pinctrl_dev_get_drvdata(struct pinctrl_dev *pctldev); struct pinctrl_dev; -/* Sufficiently stupid default function when pinctrl is not in use */ +/* Sufficiently stupid default functions when pinctrl is not in use */ static inline bool pin_is_valid(struct pinctrl_dev *pctldev, int pin) { return pin >= 0;