diff options
Diffstat (limited to 'drivers/pinctrl/pinmux.c')
| -rw-r--r-- | drivers/pinctrl/pinmux.c | 1190 |
1 files changed, 1190 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c new file mode 100644 index 00000000000..a5467f8709e --- /dev/null +++ b/drivers/pinctrl/pinmux.c @@ -0,0 +1,1190 @@ +/* + * Core driver for the pin muxing portions of the pin control subsystem + * + * 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 <linus.walleij@linaro.org> + * + * License terms: GNU General Public License (GPL) version 2 + */ +#define pr_fmt(fmt) "pinmux core: " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/radix-tree.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/sysfs.h> +#include <linux/debugfs.h> +#include <linux/seq_file.h> +#include <linux/pinctrl/machine.h> +#include <linux/pinctrl/pinmux.h> +#include "core.h" + +/* List of pinmuxes */ +static DEFINE_MUTEX(pinmux_list_mutex); +static LIST_HEAD(pinmux_list); + +/* List of pinmux hogs */ +static DEFINE_MUTEX(pinmux_hoglist_mutex); +static LIST_HEAD(pinmux_hoglist); + +/* Global pinmux maps, we allow one set only */ +static struct pinmux_map const *pinmux_maps; +static unsigned pinmux_maps_num; + +/** + * struct pinmux_group - group list item for pinmux groups + * @node: pinmux group list node + * @group_selector: the group selector for this group + */ +struct pinmux_group { + struct list_head node; + unsigned group_selector; +}; + +/** + * struct pinmux - per-device pinmux state holder + * @node: global list node + * @dev: the device using this pinmux + * @usecount: the number of active users of this mux setting, used to keep + * track of nested use cases + * @pins: an array of discrete physical pins used in this mapping, taken + * from the global pin enumeration space (copied from pinmux map) + * @num_pins: the number of pins in this mapping array, i.e. the number of + * elements in .pins so we can iterate over that array (copied from + * pinmux map) + * @pctldev: pin control device handling this pinmux + * @func_selector: the function selector for the pinmux device handling + * this pinmux + * @groups: the group selectors for the pinmux device and + * selector combination handling this pinmux, this is a list that + * will be traversed on all pinmux operations such as + * get/put/enable/disable + * @mutex: a lock for the pinmux state holder + */ +struct pinmux { + struct list_head node; + struct device *dev; + unsigned usecount; + struct pinctrl_dev *pctldev; + unsigned func_selector; + struct list_head groups; + struct mutex mutex; +}; + +/** + * struct pinmux_hog - a list item to stash mux hogs + * @node: pinmux hog list node + * @map: map entry responsible for this hogging + * @pmx: the pinmux hogged by this item + */ +struct pinmux_hog { + struct list_head node; + struct pinmux_map const *map; + struct pinmux *pmx; +}; + +/** + * pin_request() - request a single pin to be muxed in, typically for GPIO + * @pin: the pin number in the global pin space + * @function: a functional name to give to this pin, passed to the driver + * so it knows what function to mux in, e.g. the string "gpioNN" + * means that you want to mux in the pin for use as GPIO number NN + * @gpio: if this request concerns a single GPIO pin + * @gpio_range: the range matching the GPIO pin if this is a request for a + * single GPIO pin + */ +static int pin_request(struct pinctrl_dev *pctldev, + int pin, const char *function, bool gpio, + struct pinctrl_gpio_range *gpio_range) +{ + struct pin_desc *desc; + const struct pinmux_ops *ops = pctldev->desc->pmxops; + int status = -EINVAL; + + dev_dbg(&pctldev->dev, "request pin %d for %s\n", pin, function); + + if (!pin_is_valid(pctldev, pin)) { + dev_err(&pctldev->dev, "pin is invalid\n"); + return -EINVAL; + } + + if (!function) { + dev_err(&pctldev->dev, "no function name given\n"); + return -EINVAL; + } + + desc = pin_desc_get(pctldev, pin); + if (desc == NULL) { + dev_err(&pctldev->dev, + "pin is not registered so it cannot be requested\n"); + goto out; + } + + spin_lock(&desc->lock); + if (desc->mux_function) { + spin_unlock(&desc->lock); + dev_err(&pctldev->dev, + "pin already requested\n"); + goto out; + } + desc->mux_function = function; + spin_unlock(&desc->lock); + + /* Let each pin increase references to this module */ + if (!try_module_get(pctldev->owner)) { + dev_err(&pctldev->dev, + "could not increase module refcount for pin %d\n", + pin); + status = -EINVAL; + goto out_free_pin; + } + + /* + * If there is no kind of request function for the pin we just assume + * we got it by default and proceed. + */ + if (gpio && ops->gpio_request_enable) + /* This requests and enables a single GPIO pin */ + status = ops->gpio_request_enable(pctldev, gpio_range, pin); + else if (ops->request) + status = ops->request(pctldev, pin); + else + status = 0; + + if (status) + dev_err(&pctldev->dev, "->request on device %s failed " + "for pin %d\n", + pctldev->desc->name, pin); +out_free_pin: + if (status) { + spin_lock(&desc->lock); + desc->mux_function = NULL; + spin_unlock(&desc->lock); + } +out: + if (status) + dev_err(&pctldev->dev, "pin-%d (%s) status %d\n", + pin, function ? : "?", status); + + return status; +} + +/** + * pin_free() - release a single muxed in pin so something else can be muxed + * @pctldev: pin controller device handling this pin + * @pin: the pin to free + * @free_func: whether to free the pin's assigned function name string + */ +static void pin_free(struct pinctrl_dev *pctldev, int pin, int free_func) +{ + const struct pinmux_ops *ops = pctldev->desc->pmxops; + struct pin_desc *desc; + + desc = pin_desc_get(pctldev, pin); + if (desc == NULL) { + dev_err(&pctldev->dev, + "pin is not registered so it cannot be freed\n"); + return; + } + + if (ops->free) + ops->free(pctldev, pin); + + spin_lock(&desc->lock); + if (free_func) + kfree(desc->mux_function); + desc->mux_function = NULL; + spin_unlock(&desc->lock); + module_put(pctldev->owner); +} + +/** + * pinmux_request_gpio() - request a single pin to be muxed in as GPIO + * @gpio: the GPIO pin number from the GPIO subsystem number space + */ +int pinmux_request_gpio(unsigned gpio) +{ + char gpiostr[16]; + const char *function; + struct pinctrl_dev *pctldev; + struct pinctrl_gpio_range *range; + int ret; + int pin; + + ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); + if (ret) + return -EINVAL; + + /* Convert to the pin controllers number space */ + pin = gpio - range->base; + + /* Conjure some name stating what chip and pin this is taken by */ + snprintf(gpiostr, 15, "%s:%d", range->name, gpio); + + function = kstrdup(gpiostr, GFP_KERNEL); + if (!function) + return -EINVAL; + + ret = pin_request(pctldev, pin, function, true, range); + if (ret < 0) + kfree(function); + + return ret; +} +EXPORT_SYMBOL_GPL(pinmux_request_gpio); + +/** + * pinmux_free_gpio() - free a single pin, currently used as GPIO + * @gpio: the GPIO pin number from the GPIO subsystem number space + */ +void pinmux_free_gpio(unsigned gpio) +{ + struct pinctrl_dev *pctldev; + struct pinctrl_gpio_range *range; + int ret; + int pin; + + ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range); + if (ret) + return; + + /* Convert to the pin controllers number space */ + pin = gpio - range->base; + + pin_free(pctldev, pin, true); +} +EXPORT_SYMBOL_GPL(pinmux_free_gpio); + +/** + * pinmux_register_mappings() - register a set of pinmux mappings + * @maps: the pinmux mappings table to register + * @num_maps: the number of maps in the mapping table + * + * Only call this once during initialization of your machine, the function is + * tagged as __init and won't be callable after init has completed. The map + * passed into this function will be owned by the pinmux core and cannot be + * free:d. + */ +int __init pinmux_register_mappings(struct pinmux_map const *maps, + unsigned num_maps) +{ + int i; + + if (pinmux_maps != NULL) { + pr_err("pinmux mappings already registered, you can only " + "register one set of maps\n"); + return -EINVAL; + } + + pr_debug("add %d pinmux maps\n", num_maps); + for (i = 0; i < num_maps; i++) { + /* Sanity check the mapping */ + if (!maps[i].name) { + pr_err("failed to register map %d: " + "no map name given\n", i); + return -EINVAL; + } + if (!maps[i].ctrl_dev && !maps[i].ctrl_dev_name) { + pr_err("failed to register map %s (%d): " + "no pin control device given\n", + maps[i].name, i); + return -EINVAL; + } + if (!maps[i].function) { + pr_err("failed to register map %s (%d): " + "no function ID given\n", maps[i].name, i); + return -EINVAL; + } + + if (!maps[i].dev && !maps[i].dev_name) + pr_debug("add system map %s function %s with no device\n", + maps[i].name, + maps[i].function); + else + pr_debug("register map %s, function %s\n", + maps[i].name, + maps[i].function); + } + + pinmux_maps = maps; + pinmux_maps_num = num_maps; + + return 0; +} + +/** + * acquire_pins() - acquire all the pins for a certain funcion on a pinmux + * @pctldev: the device to take the pins on + * @func_selector: the function selector to acquire the pins for + * @group_selector: the group selector containing the pins to acquire + */ +static int acquire_pins(struct pinctrl_dev *pctldev, + unsigned func_selector, + unsigned group_selector) +{ + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + const struct pinmux_ops *pmxops = pctldev->desc->pmxops; + const char *func = pmxops->get_function_name(pctldev, + func_selector); + const unsigned *pins; + unsigned num_pins; + int ret; + int i; + + ret = pctlops->get_group_pins(pctldev, group_selector, + &pins, &num_pins); + if (ret) + return ret; + + dev_dbg(&pctldev->dev, "requesting the %u pins from group %u\n", + num_pins, group_selector); + + /* Try to allocate all pins in this group, one by one */ + for (i = 0; i < num_pins; i++) { + ret = pin_request(pctldev, pins[i], func, false, NULL); + if (ret) { + dev_err(&pctldev->dev, + "could not get pin %d for function %s " + "on device %s - conflicting mux mappings?\n", + pins[i], func ? : "(undefined)", + pinctrl_dev_get_name(pctldev)); + /* On error release all taken pins */ + i--; /* this pin just failed */ + for (; i >= 0; i--) + pin_free(pctldev, pins[i], false); + return -ENODEV; + } + } + return 0; +} + +/** + * release_pins() - release pins taken by earlier acquirement + * @pctldev: the device to free the pinx on + * @group_selector: the group selector containing the pins to free + */ +static void release_pins(struct pinctrl_dev *pctldev, + unsigned group_selector) +{ + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + const unsigned *pins; + unsigned num_pins; + int ret; + int i; + + ret = pctlops->get_group_pins(pctldev, group_selector, + &pins, &num_pins); + if (ret) { + dev_err(&pctldev->dev, "could not get pins to release for " + "group selector %d\n", + group_selector); + return; + } + for (i = 0; i < num_pins; i++) + pin_free(pctldev, pins[i], false); +} + +/** + * pinmux_get_group_selector() - returns the group selector for a group + * @pctldev: the pin controller handling the group + * @pin_group: the pin group to look up + */ +static int pinmux_get_group_selector(struct pinctrl_dev *pctldev, + const char *pin_group) +{ + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + unsigned group_selector = 0; + + while (pctlops->list_groups(pctldev, group_selector) >= 0) { + const char *gname = pctlops->get_group_name(pctldev, + group_selector); + if (!strcmp(gname, pin_group)) { + dev_dbg(&pctldev->dev, + "found group selector %u for %s\n", + group_selector, + pin_group); + return group_selector; + } + + group_selector++; + } + + dev_err(&pctldev->dev, "does not have pin group %s\n", + pin_group); + + return -EINVAL; +} + +/** + * pinmux_check_pin_group() - check function and pin group combo + * @pctldev: device to check the pin group vs function for + * @func_selector: the function selector to check the pin group for, we have + * already looked this up in the calling function + * @pin_group: the pin group to match to the function + * + * This function will check that the pinmux driver can supply the + * selected pin group for a certain function, returns the group selector if + * the group and function selector will work fine together, else returns + * negative + */ +static int pinmux_check_pin_group(struct pinctrl_dev *pctldev, + unsigned func_selector, + const char *pin_group) +{ + const struct pinmux_ops *pmxops = pctldev->desc->pmxops; + const struct pinctrl_ops *pctlops = pctldev->desc->pctlops; + int ret; + + /* + * If the driver does not support different pin groups for the + * functions, we only support group 0, and assume this exists. + */ + if (!pctlops || !pctlops->list_groups) + return 0; + + /* + * Passing NULL (no specific group) will select the first and + * hopefully only group of pins available for this function. + */ + if (!pin_group) { + char const * const *groups; + unsigned num_groups; + + ret = pmxops->get_function_groups(pctldev, func_selector, + &groups, &num_groups); + if (ret) + return ret; + if (num_groups < 1) + return -EINVAL; + ret = pinmux_get_group_selector(pctldev, groups[0]); + if (ret < 0) { + dev_err(&pctldev->dev, + "function %s wants group %s but the pin " + "controller does not seem to have that group\n", + pmxops->get_function_name(pctldev, func_selector), + groups[0]); + return ret; + } + + if (num_groups > 1) + dev_dbg(&pctldev->dev, + "function %s support more than one group, " + "default-selecting first group %s (%d)\n", + pmxops->get_function_name(pctldev, func_selector), + groups[0], + ret); + + return ret; + } + + dev_dbg(&pctldev->dev, + "check if we have pin group %s on controller %s\n", + pin_group, pinctrl_dev_get_name(pctldev)); + + ret = pinmux_get_group_selector(pctldev, pin_group); + if (ret < 0) { + dev_dbg(&pctldev->dev, + "%s does not support pin group %s with function %s\n", + pinctrl_dev_get_name(pctldev), + pin_group, + pmxops->get_function_name(pctldev, func_selector)); + } + return ret; +} + +/** + * pinmux_search_function() - check pin control driver for a certain function + * @pctldev: device to check for function and position + * @map: function map containing the function and position to look for + * @func_selector: returns the applicable function selector if found + * @group_selector: returns the applicable group selector if found + * + * This will search the pinmux driver for an applicable + * function with a specific pin group, returns 0 if these can be mapped + * negative otherwise + */ +static int pinmux_search_function(struct pinctrl_dev *pctldev, + struct pinmux_map const *map, + unsigned *func_selector, + unsigned *group_selector) +{ + const struct pinmux_ops *ops = pctldev->desc->pmxops; + unsigned selector = 0; + + /* See if this pctldev has this function */ + while (ops->list_functions(pctldev, selector) >= 0) { + const char *fname = ops->get_function_name(pctldev, + selector); + int ret; + + if (!strcmp(map->function, fname)) { + /* Found the function, check pin group */ + ret = pinmux_check_pin_group(pctldev, selector, + map->group); + if (ret < 0) + return ret; + + /* This function and group selector can be used */ + *func_selector = selector; + *group_selector = ret; + return 0; + + } + selector++; + } + + pr_err("%s does not support function %s\n", + pinctrl_dev_get_name(pctldev), map->function); + return -EINVAL; +} + +/** + * pinmux_enable_muxmap() - enable a map entry for a certain pinmux + */ +static int pinmux_enable_muxmap(struct pinctrl_dev *pctldev, + struct pinmux *pmx, + struct device *dev, + const char *devname, + struct pinmux_map const *map) +{ + unsigned func_selector; + unsigned group_selector; + struct pinmux_group *grp; + int ret; + + /* + * Note that we're not locking the pinmux mutex here, because + * this is only called at pinmux initialization time when it + * has not been added to any list and thus is not reachable + * by anyone else. + */ + + if (pmx->pctldev && pmx->pctldev != pctldev) { + dev_err(&pctldev->dev, + "different pin control devices given for device %s, " + "function %s\n", + devname, + map->function); + return -EINVAL; + } + pmx->dev = dev; + pmx->pctldev = pctldev; + + /* Now go into the driver and try to match a function and group */ + ret = pinmux_search_function(pctldev, map, &func_selector, + &group_selector); + if (ret < 0) + return ret; + + /* + * If the function selector is already set, it needs to be identical, + * we support several groups with one function but not several + * functions with one or several groups in the same pinmux. + */ + if (pmx->func_selector != UINT_MAX && + pmx->func_selector != func_selector) { + dev_err(&pctldev->dev, + "dual function defines in the map for device %s\n", + devname); + return -EINVAL; + } + pmx->func_selector = func_selector; + + /* Now add this group selector, we may have many of them */ + grp = kmalloc(sizeof(struct pinmux_group), GFP_KERNEL); + if (!grp) + return -ENOMEM; + grp->group_selector = group_selector; + ret = acquire_pins(pctldev, func_selector, group_selector); + if (ret) { + kfree(grp); + return ret; + } + list_add(&grp->node, &pmx->groups); + + return 0; +} + +static void pinmux_free_groups(struct pinmux *pmx) +{ + struct list_head *node, *tmp; + + list_for_each_safe(node, tmp, &pmx->groups) { + struct pinmux_group *grp = + list_entry(node, struct pinmux_group, node); + /* Release all pins taken by this group */ + release_pins(pmx->pctldev, grp->group_selector); + list_del(node); + kfree(grp); + } +} + +/** + * pinmux_get() - retrieves the pinmux for a certain device + * @dev: the device to get the pinmux for + * @name: an optional specific mux mapping name or NULL, the name is only + * needed if you want to have more than one mapping per device, or if you + * need an anonymous pinmux (not tied to any specific device) + */ +struct pinmux *pinmux_get(struct device *dev, const char *name) +{ + + struct pinmux_map const *map = NULL; + struct pinctrl_dev *pctldev = NULL; + const char *devname = NULL; + struct pinmux *pmx; + bool found_map; + unsigned num_maps = 0; + int ret = -ENODEV; + int i; + + /* We must have dev or ID or both */ + if (!dev && !name) + return ERR_PTR(-EINVAL); + + if (dev) + devname = dev_name(dev); + + pr_debug("get mux %s for device %s\n", name, + devname ? devname : "(none)"); + + /* + * create the state cookie holder struct pinmux for each + * mapping, this is what consumers will get when requesting + * a pinmux handle with pinmux_get() + */ + pmx = kzalloc(sizeof(struct pinmux), GFP_KERNEL); + if (pmx == NULL) + return ERR_PTR(-ENOMEM); + mutex_init(&pmx->mutex); + pmx->func_selector = UINT_MAX; + INIT_LIST_HEAD(&pmx->groups); + + /* Iterate over the pinmux maps to locate the right ones */ + for (i = 0; i < pinmux_maps_num; i++) { + map = &pinmux_maps[i]; + found_map = false; + + /* + * First, try to find the pctldev given in the map + */ + pctldev = get_pinctrl_dev_from_dev(map->ctrl_dev, + map->ctrl_dev_name); + if (!pctldev) { + const char *devname = NULL; + + if (map->ctrl_dev) + devname = dev_name(map->ctrl_dev); + else if (map->ctrl_dev_name) + devname = map->ctrl_dev_name; + + pr_warning("could not find a pinctrl device for pinmux " + "function %s, fishy, they shall all have one\n", + map->function); + pr_warning("given pinctrl device name: %s", + devname ? devname : "UNDEFINED"); + + /* Continue to check the other mappings anyway... */ + continue; + } + + pr_debug("in map, found pctldev %s to handle function %s", + dev_name(&pctldev->dev), map->function); + + + /* + * If we're looking for a specific named map, this must match, + * else we loop and look for the next. + */ + if (name != NULL) { + if (map->name == NULL) + continue; + if (strcmp(map->name, name)) + continue; + } + + /* + * This is for the case where no device name is given, we + * already know that the function name matches from above + * code. + */ + if (!map->dev_name && (name != NULL)) + found_map = true; + + /* If the mapping has a device set up it must match */ + if (map->dev_name && + (!devname || !strcmp(map->dev_name, devname))) + /* MATCH! */ + found_map = true; + + /* If this map is applicable, then apply it */ + if (found_map) { + ret = pinmux_enable_muxmap(pctldev, pmx, dev, + devname, map); + if (ret) { + pinmux_free_groups(pmx); + kfree(pmx); + return ERR_PTR(ret); + } + num_maps++; + } + } + + + /* We should have atleast one map, right */ + if (!num_maps) { + pr_err("could not find any mux maps for device %s, ID %s\n", + devname ? devname : "(anonymous)", + name ? name : "(undefined)"); + kfree(pmx); + return ERR_PTR(-EINVAL); + } + + pr_debug("found %u mux maps for device %s, UD %s\n", + num_maps, + devname ? devname : "(anonymous)", + name ? name : "(undefined)"); + + /* Add the pinmux to the global list */ + mutex_lock(&pinmux_list_mutex); + list_add(&pmx->node, &pinmux_list); + mutex_unlock(&pinmux_list_mutex); + + return pmx; +} +EXPORT_SYMBOL_GPL(pinmux_get); + +/** + * pinmux_put() - release a previously claimed pinmux + * @pmx: a pinmux previously claimed by pinmux_get() + */ +void pinmux_put(struct pinmux *pmx) +{ + if (pmx == NULL) + return; + + mutex_lock(&pmx->mutex); + if (pmx->usecount) + pr_warn("releasing pinmux with active users!\n"); + /* Free the groups and all acquired pins */ + pinmux_free_groups(pmx); + mutex_unlock(&pmx->mutex); + + /* Remove from list */ + mutex_lock(&pinmux_list_mutex); + list_del(&pmx->node); + mutex_unlock(&pinmux_list_mutex); + + kfree(pmx); +} +EXPORT_SYMBOL_GPL(pinmux_put); + +/** + * pinmux_enable() - enable a certain pinmux setting + * @pmx: the pinmux to enable, previously claimed by pinmux_get() + */ +int pinmux_enable(struct pinmux *pmx) +{ + int ret = 0; + + if (pmx == NULL) + return -EINVAL; + mutex_lock(&pmx->mutex); + if (pmx->usecount++ == 0) { + struct pinctrl_dev *pctldev = pmx->pctldev; + const struct pinmux_ops *ops = pctldev->desc->pmxops; + struct pinmux_group *grp; + + list_for_each_entry(grp, &pmx->groups, node) { + ret = ops->enable(pctldev, pmx->func_selector, + grp->group_selector); + if (ret) { + /* + * TODO: call disable() on all groups we called + * enable() on to this point? + */ + pmx->usecount--; + break; + } + } + } + mutex_unlock(&pmx->mutex); + return ret; +} +EXPORT_SYMBOL_GPL(pinmux_enable); + +/** + * pinmux_disable() - disable a certain pinmux setting + * @pmx: the pinmux to disable, previously claimed by pinmux_get() + */ +void pinmux_disable(struct pinmux *pmx) +{ + if (pmx == NULL) + return; + + mutex_lock(&pmx->mutex); + if (--pmx->usecount == 0) { + struct pinctrl_dev *pctldev = pmx->pctldev; + const struct pinmux_ops *ops = pctldev->desc->pmxops; + struct pinmux_group *grp; + + list_for_each_entry(grp, &pmx->groups, node) { + ops->disable(pctldev, pmx->func_selector, + grp->group_selector); + } + } + mutex_unlock(&pmx->mutex); +} +EXPORT_SYMBOL_GPL(pinmux_disable); + +int pinmux_check_ops(const struct pinmux_ops *ops) +{ + /* Check that we implement required operations */ + if (!ops->list_functions || + !ops->get_function_name || + !ops->get_function_groups || + !ops->enable || + !ops->disable) + return -EINVAL; + + return 0; +} + +/* Hog a single map entry and add to the hoglist */ +static int pinmux_hog_map(struct pinctrl_dev *pctldev, + struct pinmux_map const *map) +{ + struct pinmux_hog *hog; + struct pinmux *pmx; + int ret; + + if (map->dev || map->dev_name) { + /* + * TODO: the day we have device tree support, we can + * traverse the device tree and hog to specific device nodes + * without any problems, so then we can hog pinmuxes for + * all devices that just want a static pin mux at this point. + */ + dev_err(&pctldev->dev, "map %s wants to hog a non-system " + "pinmux, this is not going to work\n", map->name); + return -EINVAL; + } + + hog = kzalloc(sizeof(struct pinmux_hog), GFP_KERNEL); + if (!hog) + return -ENOMEM; + + pmx = pinmux_get(NULL, map->name); + if (IS_ERR(pmx)) { + kfree(hog); + dev_err(&pctldev->dev, + "could not get the %s pinmux mapping for hogging\n", + map->name); + return PTR_ERR(pmx); + } + + ret = pinmux_enable(pmx); + if (ret) { + pinmux_put(pmx); + kfree(hog); + dev_err(&pctldev->dev, + "could not enable the %s pinmux mapping for hogging\n", + map->name); + return ret; + } + + hog->map = map; + hog->pmx = pmx; + + dev_info(&pctldev->dev, "hogged map %s, function %s\n", map->name, + map->function); + mutex_lock(&pctldev->pinmux_hogs_lock); + list_add(&hog->node, &pctldev->pinmux_hogs); + mutex_unlock(&pctldev->pinmux_hogs_lock); + + return 0; +} + +/** + * pinmux_hog_maps() - hog specific map entries on controller device + * @pctldev: the pin control device to hog entries on + * + * When the pin controllers are registered, there may be some specific pinmux + * map entries that need to be hogged, i.e. get+enabled until the system shuts + * down. + */ +int pinmux_hog_maps(struct pinctrl_dev *pctldev) +{ + struct device *dev = &pctldev->dev; + const char *devname = dev_name(dev); + int ret; + int i; + + INIT_LIST_HEAD(&pctldev->pinmux_hogs); + mutex_init(&pctldev->pinmux_hogs_lock); + + for (i = 0; i < pinmux_maps_num; i++) { + struct pinmux_map const *map = &pinmux_maps[i]; + + if (((map->ctrl_dev == dev) || + !strcmp(map->ctrl_dev_name, devname)) && + map->hog_on_boot) { + /* OK time to hog! */ + ret = pinmux_hog_map(pctldev, map); + if (ret) + return ret; + } + } + return 0; +} + +/** + * pinmux_hog_maps() - unhog specific map entries on controller device + * @pctldev: the pin control device to unhog entries on + */ +void pinmux_unhog_maps(struct pinctrl_dev *pctldev) +{ + struct list_head *node, *tmp; + + mutex_lock(&pctldev->pinmux_hogs_lock); + list_for_each_safe(node, tmp, &pctldev->pinmux_hogs) { + struct pinmux_hog *hog = + list_entry(node, struct pinmux_hog, node); + pinmux_disable(hog->pmx); + pinmux_put(hog->pmx); + list_del(node); + kfree(hog); + } + mutex_unlock(&pctldev->pinmux_hogs_lock); +} + +#ifdef CONFIG_DEBUG_FS + +/* Called from pincontrol core */ +static int pinmux_functions_show(struct seq_file *s, void *what) +{ + struct pinctrl_dev *pctldev = s->private; + const struct pinmux_ops *pmxops = pctldev->desc->pmxops; + unsigned func_selector = 0; + + while (pmxops->list_functions(pctldev, func_selector) >= 0) { + const char *func = pmxops->get_function_name(pctldev, + func_selector); + const char * const *groups; + unsigned num_groups; + int ret; + int i; + + ret = pmxops->get_function_groups(pctldev, func_selector, + &groups, &num_groups); + if (ret) + seq_printf(s, "function %s: COULD NOT GET GROUPS\n", + func); + + seq_printf(s, "function: %s, groups = [ ", func); + for (i = 0; i < num_groups; i++) + seq_printf(s, "%s ", groups[i]); + seq_puts(s, "]\n"); + + func_selector++; + + } + + return 0; +} + +static int pinmux_pins_show(struct seq_file *s, void *what) +{ + struct pinctrl_dev *pctldev = s->private; + unsigned pin; + + seq_puts(s, "Pinmux settings per pin\n"); + seq_puts(s, "Format: pin (name): pinmuxfunction\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): %s\n", pin, + desc->name ? desc->name : "unnamed", + desc->mux_function ? desc->mux_function + : "UNCLAIMED"); + } + + return 0; +} + +static int pinmux_hogs_show(struct seq_file *s, void *what) +{ + struct pinctrl_dev *pctldev = s->private; + struct pinmux_hog *hog; + + seq_puts(s, "Pinmux map hogs held by device\n"); + + list_for_each_entry(hog, &pctldev->pinmux_hogs, node) + seq_printf(s, "%s\n", hog->map->name); + + return 0; +} + +static int pinmux_show(struct seq_file *s, void *what) +{ + struct pinmux *pmx; + + seq_puts(s, "Requested pinmuxes and their maps:\n"); + list_for_each_entry(pmx, &pinmux_list, node) { + struct pinctrl_dev *pctldev = pmx->pctldev; + const struct pinmux_ops *pmxops; + const struct pinctrl_ops *pctlops; + struct pinmux_group *grp; + + if (!pctldev) { + seq_puts(s, "NO PIN CONTROLLER DEVICE\n"); + continue; + } + + pmxops = pctldev->desc->pmxops; + pctlops = pctldev->desc->pctlops; + + seq_printf(s, "device: %s function: %s (%u),", + pinctrl_dev_get_name(pmx->pctldev), + pmxops->get_function_name(pctldev, pmx->func_selector), + pmx->func_selector); + + seq_printf(s, " groups: ["); + list_for_each_entry(grp, &pmx->groups, node) { + seq_printf(s, " %s (%u)", + pctlops->get_group_name(pctldev, grp->group_selector), + grp->group_selector); + } + seq_printf(s, " ]"); + + seq_printf(s, " users: %u map-> %s\n", + pmx->usecount, + pmx->dev ? dev_name(pmx->dev) : "(system)"); + } + + return 0; +} + +static int pinmux_maps_show(struct seq_file *s, void *what) +{ + int i; + + seq_puts(s, "Pinmux maps:\n"); + + for (i = 0; i < pinmux_maps_num; i++) { + struct pinmux_map const *map = &pinmux_maps[i]; + + seq_printf(s, "%s:\n", map->name); + if (map->dev || map->dev_name) + seq_printf(s, " device: %s\n", + map->dev ? dev_name(map->dev) : + map->dev_name); + else + seq_printf(s, " SYSTEM MUX\n"); + seq_printf(s, " controlling device %s\n", + map->ctrl_dev ? dev_name(map->ctrl_dev) : + map->ctrl_dev_name); + seq_printf(s, " function: %s\n", map->function); + seq_printf(s, " group: %s\n", map->group ? map->group : + "(default)"); + } + return 0; +} + +static int pinmux_functions_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinmux_functions_show, inode->i_private); +} + +static int pinmux_pins_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinmux_pins_show, inode->i_private); +} + +static int pinmux_hogs_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinmux_hogs_show, inode->i_private); +} + +static int pinmux_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinmux_show, NULL); +} + +static int pinmux_maps_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinmux_maps_show, NULL); +} + +static const struct file_operations pinmux_functions_ops = { + .open = pinmux_functions_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations pinmux_pins_ops = { + .open = pinmux_pins_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations pinmux_hogs_ops = { + .open = pinmux_hogs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations pinmux_ops = { + .open = pinmux_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static const struct file_operations pinmux_maps_ops = { + .open = pinmux_maps_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +void pinmux_init_device_debugfs(struct dentry *devroot, + struct pinctrl_dev *pctldev) +{ + debugfs_create_file("pinmux-functions", S_IFREG | S_IRUGO, + devroot, pctldev, &pinmux_functions_ops); + debugfs_create_file("pinmux-pins", S_IFREG | S_IRUGO, + devroot, pctldev, &pinmux_pins_ops); + debugfs_create_file("pinmux-hogs", S_IFREG | S_IRUGO, + devroot, pctldev, &pinmux_hogs_ops); +} + +void pinmux_init_debugfs(struct dentry *subsys_root) +{ + debugfs_create_file("pinmuxes", S_IFREG | S_IRUGO, + subsys_root, NULL, &pinmux_ops); + debugfs_create_file("pinmux-maps", S_IFREG | S_IRUGO, + subsys_root, NULL, &pinmux_maps_ops); +} + +#endif /* CONFIG_DEBUG_FS */ |