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-rw-r--r--drivers/pinctrl/pinmux.c956
1 files changed, 956 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
new file mode 100644
index 000000000..f94d43b08
--- /dev/null
+++ b/drivers/pinctrl/pinmux.c
@@ -0,0 +1,956 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Core driver for the pin muxing portions of the pin control subsystem
+ *
+ * Copyright (C) 2011-2012 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>
+ *
+ * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
+ */
+#define pr_fmt(fmt) "pinmux core: " fmt
+
+#include <linux/ctype.h>
+#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/string.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/pinctrl/machine.h>
+#include <linux/pinctrl/pinmux.h>
+#include "core.h"
+#include "pinmux.h"
+
+int pinmux_check_ops(struct pinctrl_dev *pctldev)
+{
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+ unsigned nfuncs;
+ unsigned selector = 0;
+
+ /* Check that we implement required operations */
+ if (!ops ||
+ !ops->get_functions_count ||
+ !ops->get_function_name ||
+ !ops->get_function_groups ||
+ !ops->set_mux) {
+ dev_err(pctldev->dev, "pinmux ops lacks necessary functions\n");
+ return -EINVAL;
+ }
+ /* Check that all functions registered have names */
+ nfuncs = ops->get_functions_count(pctldev);
+ while (selector < nfuncs) {
+ const char *fname = ops->get_function_name(pctldev,
+ selector);
+ if (!fname) {
+ dev_err(pctldev->dev, "pinmux ops has no name for function%u\n",
+ selector);
+ return -EINVAL;
+ }
+ selector++;
+ }
+
+ return 0;
+}
+
+int pinmux_validate_map(const struct pinctrl_map *map, int i)
+{
+ if (!map->data.mux.function) {
+ pr_err("failed to register map %s (%d): no function given\n",
+ map->name, i);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * pinmux_can_be_used_for_gpio() - check if a specific pin
+ * is either muxed to a different function or used as gpio.
+ *
+ * @pctldev: the associated pin controller device
+ * @pin: the pin number in the global pin space
+ *
+ * Controllers not defined as strict will always return true,
+ * menaning that the gpio can be used.
+ */
+bool pinmux_can_be_used_for_gpio(struct pinctrl_dev *pctldev, unsigned pin)
+{
+ struct pin_desc *desc = pin_desc_get(pctldev, pin);
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+
+ /* Can't inspect pin, assume it can be used */
+ if (!desc || !ops)
+ return true;
+
+ if (ops->strict && desc->mux_usecount)
+ return false;
+
+ return !(ops->strict && !!desc->gpio_owner);
+}
+
+/**
+ * pin_request() - request a single pin to be muxed in, typically for GPIO
+ * @pctldev: the associated pin controller device
+ * @pin: the pin number in the global pin space
+ * @owner: a representation of the owner of this pin; typically the device
+ * name that controls its mux function, or the requested GPIO name
+ * @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 *owner,
+ struct pinctrl_gpio_range *gpio_range)
+{
+ struct pin_desc *desc;
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+ int status = -EINVAL;
+
+ desc = pin_desc_get(pctldev, pin);
+ if (desc == NULL) {
+ dev_err(pctldev->dev,
+ "pin %d is not registered so it cannot be requested\n",
+ pin);
+ goto out;
+ }
+
+ dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
+ pin, desc->name, owner);
+
+ if ((!gpio_range || ops->strict) &&
+ desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
+ dev_err(pctldev->dev,
+ "pin %s already requested by %s; cannot claim for %s\n",
+ desc->name, desc->mux_owner, owner);
+ goto out;
+ }
+
+ if ((gpio_range || ops->strict) && desc->gpio_owner) {
+ dev_err(pctldev->dev,
+ "pin %s already requested by %s; cannot claim for %s\n",
+ desc->name, desc->gpio_owner, owner);
+ goto out;
+ }
+
+ if (gpio_range) {
+ desc->gpio_owner = owner;
+ } else {
+ desc->mux_usecount++;
+ if (desc->mux_usecount > 1)
+ return 0;
+
+ desc->mux_owner = owner;
+ }
+
+ /* 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_range && 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() failed for pin %d\n", pin);
+ module_put(pctldev->owner);
+ }
+
+out_free_pin:
+ if (status) {
+ if (gpio_range) {
+ desc->gpio_owner = NULL;
+ } else {
+ desc->mux_usecount--;
+ if (!desc->mux_usecount)
+ desc->mux_owner = NULL;
+ }
+ }
+out:
+ if (status)
+ dev_err(pctldev->dev, "pin-%d (%s) status %d\n",
+ pin, owner, 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
+ * @gpio_range: the range matching the GPIO pin if this is a request for a
+ * single GPIO pin
+ *
+ * This function returns a pointer to the previous owner. This is used
+ * for callers that dynamically allocate an owner name so it can be freed
+ * once the pin is free. This is done for GPIO request functions.
+ */
+static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
+ struct pinctrl_gpio_range *gpio_range)
+{
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+ struct pin_desc *desc;
+ const char *owner;
+
+ desc = pin_desc_get(pctldev, pin);
+ if (desc == NULL) {
+ dev_err(pctldev->dev,
+ "pin is not registered so it cannot be freed\n");
+ return NULL;
+ }
+
+ if (!gpio_range) {
+ /*
+ * A pin should not be freed more times than allocated.
+ */
+ if (WARN_ON(!desc->mux_usecount))
+ return NULL;
+ desc->mux_usecount--;
+ if (desc->mux_usecount)
+ return NULL;
+ }
+
+ /*
+ * If there is no kind of request function for the pin we just assume
+ * we got it by default and proceed.
+ */
+ if (gpio_range && ops->gpio_disable_free)
+ ops->gpio_disable_free(pctldev, gpio_range, pin);
+ else if (ops->free)
+ ops->free(pctldev, pin);
+
+ if (gpio_range) {
+ owner = desc->gpio_owner;
+ desc->gpio_owner = NULL;
+ } else {
+ owner = desc->mux_owner;
+ desc->mux_owner = NULL;
+ desc->mux_setting = NULL;
+ }
+
+ module_put(pctldev->owner);
+
+ return owner;
+}
+
+/**
+ * pinmux_request_gpio() - request pinmuxing for a GPIO pin
+ * @pctldev: pin controller device affected
+ * @pin: the pin to mux in for GPIO
+ * @range: the applicable GPIO range
+ * @gpio: number of requested GPIO
+ */
+int pinmux_request_gpio(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin, unsigned gpio)
+{
+ const char *owner;
+ int ret;
+
+ /* Conjure some name stating what chip and pin this is taken by */
+ owner = kasprintf(GFP_KERNEL, "%s:%d", range->name, gpio);
+ if (!owner)
+ return -ENOMEM;
+
+ ret = pin_request(pctldev, pin, owner, range);
+ if (ret < 0)
+ kfree(owner);
+
+ return ret;
+}
+
+/**
+ * pinmux_free_gpio() - release a pin from GPIO muxing
+ * @pctldev: the pin controller device for the pin
+ * @pin: the affected currently GPIO-muxed in pin
+ * @range: applicable GPIO range
+ */
+void pinmux_free_gpio(struct pinctrl_dev *pctldev, unsigned pin,
+ struct pinctrl_gpio_range *range)
+{
+ const char *owner;
+
+ owner = pin_free(pctldev, pin, range);
+ kfree(owner);
+}
+
+/**
+ * pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
+ * @pctldev: the pin controller handling this pin
+ * @range: applicable GPIO range
+ * @pin: the affected GPIO pin in this controller
+ * @input: true if we set the pin as input, false for output
+ */
+int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range,
+ unsigned pin, bool input)
+{
+ const struct pinmux_ops *ops;
+ int ret;
+
+ ops = pctldev->desc->pmxops;
+
+ if (ops->gpio_set_direction)
+ ret = ops->gpio_set_direction(pctldev, range, pin, input);
+ else
+ ret = 0;
+
+ return ret;
+}
+
+static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
+ const char *function)
+{
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+ unsigned nfuncs = ops->get_functions_count(pctldev);
+ unsigned selector = 0;
+
+ /* See if this pctldev has this function */
+ while (selector < nfuncs) {
+ const char *fname = ops->get_function_name(pctldev, selector);
+
+ if (!strcmp(function, fname))
+ return selector;
+
+ selector++;
+ }
+
+ return -EINVAL;
+}
+
+int pinmux_map_to_setting(const struct pinctrl_map *map,
+ struct pinctrl_setting *setting)
+{
+ struct pinctrl_dev *pctldev = setting->pctldev;
+ const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
+ char const * const *groups;
+ unsigned num_groups;
+ int ret;
+ const char *group;
+
+ if (!pmxops) {
+ dev_err(pctldev->dev, "does not support mux function\n");
+ return -EINVAL;
+ }
+
+ ret = pinmux_func_name_to_selector(pctldev, map->data.mux.function);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "invalid function %s in map table\n",
+ map->data.mux.function);
+ return ret;
+ }
+ setting->data.mux.func = ret;
+
+ ret = pmxops->get_function_groups(pctldev, setting->data.mux.func,
+ &groups, &num_groups);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "can't query groups for function %s\n",
+ map->data.mux.function);
+ return ret;
+ }
+ if (!num_groups) {
+ dev_err(pctldev->dev,
+ "function %s can't be selected on any group\n",
+ map->data.mux.function);
+ return -EINVAL;
+ }
+ if (map->data.mux.group) {
+ group = map->data.mux.group;
+ ret = match_string(groups, num_groups, group);
+ if (ret < 0) {
+ dev_err(pctldev->dev,
+ "invalid group \"%s\" for function \"%s\"\n",
+ group, map->data.mux.function);
+ return ret;
+ }
+ } else {
+ group = groups[0];
+ }
+
+ ret = pinctrl_get_group_selector(pctldev, group);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "invalid group %s in map table\n",
+ map->data.mux.group);
+ return ret;
+ }
+ setting->data.mux.group = ret;
+
+ return 0;
+}
+
+void pinmux_free_setting(const struct pinctrl_setting *setting)
+{
+ /* This function is currently unused */
+}
+
+int pinmux_enable_setting(const struct pinctrl_setting *setting)
+{
+ struct pinctrl_dev *pctldev = setting->pctldev;
+ const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
+ const struct pinmux_ops *ops = pctldev->desc->pmxops;
+ int ret = 0;
+ const unsigned *pins = NULL;
+ unsigned num_pins = 0;
+ int i;
+ struct pin_desc *desc;
+
+ if (pctlops->get_group_pins)
+ ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
+ &pins, &num_pins);
+
+ if (ret) {
+ const char *gname;
+
+ /* errors only affect debug data, so just warn */
+ gname = pctlops->get_group_name(pctldev,
+ setting->data.mux.group);
+ dev_warn(pctldev->dev,
+ "could not get pins for group %s\n",
+ gname);
+ num_pins = 0;
+ }
+
+ /* Try to allocate all pins in this group, one by one */
+ for (i = 0; i < num_pins; i++) {
+ ret = pin_request(pctldev, pins[i], setting->dev_name, NULL);
+ if (ret) {
+ const char *gname;
+ const char *pname;
+
+ desc = pin_desc_get(pctldev, pins[i]);
+ pname = desc ? desc->name : "non-existing";
+ gname = pctlops->get_group_name(pctldev,
+ setting->data.mux.group);
+ dev_err(pctldev->dev,
+ "could not request pin %d (%s) from group %s "
+ " on device %s\n",
+ pins[i], pname, gname,
+ pinctrl_dev_get_name(pctldev));
+ goto err_pin_request;
+ }
+ }
+
+ /* Now that we have acquired the pins, encode the mux setting */
+ for (i = 0; i < num_pins; i++) {
+ desc = pin_desc_get(pctldev, pins[i]);
+ if (desc == NULL) {
+ dev_warn(pctldev->dev,
+ "could not get pin desc for pin %d\n",
+ pins[i]);
+ continue;
+ }
+ desc->mux_setting = &(setting->data.mux);
+ }
+
+ ret = ops->set_mux(pctldev, setting->data.mux.func,
+ setting->data.mux.group);
+
+ if (ret)
+ goto err_set_mux;
+
+ return 0;
+
+err_set_mux:
+ for (i = 0; i < num_pins; i++) {
+ desc = pin_desc_get(pctldev, pins[i]);
+ if (desc)
+ desc->mux_setting = NULL;
+ }
+err_pin_request:
+ /* On error release all taken pins */
+ while (--i >= 0)
+ pin_free(pctldev, pins[i], NULL);
+
+ return ret;
+}
+
+void pinmux_disable_setting(const struct pinctrl_setting *setting)
+{
+ struct pinctrl_dev *pctldev = setting->pctldev;
+ const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
+ int ret = 0;
+ const unsigned *pins = NULL;
+ unsigned num_pins = 0;
+ int i;
+ struct pin_desc *desc;
+
+ if (pctlops->get_group_pins)
+ ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
+ &pins, &num_pins);
+ if (ret) {
+ const char *gname;
+
+ /* errors only affect debug data, so just warn */
+ gname = pctlops->get_group_name(pctldev,
+ setting->data.mux.group);
+ dev_warn(pctldev->dev,
+ "could not get pins for group %s\n",
+ gname);
+ num_pins = 0;
+ }
+
+ /* Flag the descs that no setting is active */
+ for (i = 0; i < num_pins; i++) {
+ desc = pin_desc_get(pctldev, pins[i]);
+ if (desc == NULL) {
+ dev_warn(pctldev->dev,
+ "could not get pin desc for pin %d\n",
+ pins[i]);
+ continue;
+ }
+ if (desc->mux_setting == &(setting->data.mux)) {
+ pin_free(pctldev, pins[i], NULL);
+ } else {
+ const char *gname;
+
+ gname = pctlops->get_group_name(pctldev,
+ setting->data.mux.group);
+ dev_warn(pctldev->dev,
+ "not freeing pin %d (%s) as part of "
+ "deactivating group %s - it is already "
+ "used for some other setting",
+ pins[i], desc->name, gname);
+ }
+ }
+}
+
+#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 nfuncs;
+ unsigned func_selector = 0;
+
+ if (!pmxops)
+ return 0;
+
+ mutex_lock(&pctldev->mutex);
+ nfuncs = pmxops->get_functions_count(pctldev);
+ while (func_selector < nfuncs) {
+ 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);
+ func_selector++;
+ continue;
+ }
+
+ seq_printf(s, "function %d: %s, groups = [ ", func_selector, func);
+ for (i = 0; i < num_groups; i++)
+ seq_printf(s, "%s ", groups[i]);
+ seq_puts(s, "]\n");
+
+ func_selector++;
+ }
+
+ mutex_unlock(&pctldev->mutex);
+
+ return 0;
+}
+
+static int pinmux_pins_show(struct seq_file *s, void *what)
+{
+ struct pinctrl_dev *pctldev = s->private;
+ const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
+ const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
+ unsigned i, pin;
+
+ if (!pmxops)
+ return 0;
+
+ seq_puts(s, "Pinmux settings per pin\n");
+ if (pmxops->strict)
+ seq_puts(s,
+ "Format: pin (name): mux_owner|gpio_owner (strict) hog?\n");
+ else
+ seq_puts(s,
+ "Format: pin (name): mux_owner gpio_owner hog?\n");
+
+ mutex_lock(&pctldev->mutex);
+
+ /* The pin number can be retrived from the pin controller descriptor */
+ for (i = 0; i < pctldev->desc->npins; i++) {
+ struct pin_desc *desc;
+ bool is_hog = false;
+
+ pin = pctldev->desc->pins[i].number;
+ desc = pin_desc_get(pctldev, pin);
+ /* Skip if we cannot search the pin */
+ if (desc == NULL)
+ continue;
+
+ if (desc->mux_owner &&
+ !strcmp(desc->mux_owner, pinctrl_dev_get_name(pctldev)))
+ is_hog = true;
+
+ if (pmxops->strict) {
+ if (desc->mux_owner)
+ seq_printf(s, "pin %d (%s): device %s%s",
+ pin, desc->name, desc->mux_owner,
+ is_hog ? " (HOG)" : "");
+ else if (desc->gpio_owner)
+ seq_printf(s, "pin %d (%s): GPIO %s",
+ pin, desc->name, desc->gpio_owner);
+ else
+ seq_printf(s, "pin %d (%s): UNCLAIMED",
+ pin, desc->name);
+ } else {
+ /* For non-strict controllers */
+ seq_printf(s, "pin %d (%s): %s %s%s", pin, desc->name,
+ desc->mux_owner ? desc->mux_owner
+ : "(MUX UNCLAIMED)",
+ desc->gpio_owner ? desc->gpio_owner
+ : "(GPIO UNCLAIMED)",
+ is_hog ? " (HOG)" : "");
+ }
+
+ /* If mux: print function+group claiming the pin */
+ if (desc->mux_setting)
+ seq_printf(s, " function %s group %s\n",
+ pmxops->get_function_name(pctldev,
+ desc->mux_setting->func),
+ pctlops->get_group_name(pctldev,
+ desc->mux_setting->group));
+ else
+ seq_putc(s, '\n');
+ }
+
+ mutex_unlock(&pctldev->mutex);
+
+ return 0;
+}
+
+void pinmux_show_map(struct seq_file *s, const struct pinctrl_map *map)
+{
+ seq_printf(s, "group %s\nfunction %s\n",
+ map->data.mux.group ? map->data.mux.group : "(default)",
+ map->data.mux.function);
+}
+
+void pinmux_show_setting(struct seq_file *s,
+ const struct pinctrl_setting *setting)
+{
+ struct pinctrl_dev *pctldev = setting->pctldev;
+ const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
+ const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
+
+ seq_printf(s, "group: %s (%u) function: %s (%u)\n",
+ pctlops->get_group_name(pctldev, setting->data.mux.group),
+ setting->data.mux.group,
+ pmxops->get_function_name(pctldev, setting->data.mux.func),
+ setting->data.mux.func);
+}
+
+DEFINE_SHOW_ATTRIBUTE(pinmux_functions);
+DEFINE_SHOW_ATTRIBUTE(pinmux_pins);
+
+#define PINMUX_SELECT_MAX 128
+static ssize_t pinmux_select(struct file *file, const char __user *user_buf,
+ size_t len, loff_t *ppos)
+{
+ struct seq_file *sfile = file->private_data;
+ struct pinctrl_dev *pctldev = sfile->private;
+ const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
+ const char *const *groups;
+ char *buf, *gname, *fname;
+ unsigned int num_groups;
+ int fsel, gsel, ret;
+
+ if (len > PINMUX_SELECT_MAX)
+ return -ENOMEM;
+
+ buf = kzalloc(PINMUX_SELECT_MAX, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = strncpy_from_user(buf, user_buf, PINMUX_SELECT_MAX);
+ if (ret < 0)
+ goto exit_free_buf;
+ buf[len-1] = '\0';
+
+ /* remove leading and trailing spaces of input buffer */
+ gname = strstrip(buf);
+ if (*gname == '\0') {
+ ret = -EINVAL;
+ goto exit_free_buf;
+ }
+
+ /* find a separator which is a spacelike character */
+ for (fname = gname; !isspace(*fname); fname++) {
+ if (*fname == '\0') {
+ ret = -EINVAL;
+ goto exit_free_buf;
+ }
+ }
+ *fname = '\0';
+
+ /* drop extra spaces between function and group names */
+ fname = skip_spaces(fname + 1);
+ if (*fname == '\0') {
+ ret = -EINVAL;
+ goto exit_free_buf;
+ }
+
+ ret = pinmux_func_name_to_selector(pctldev, fname);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "invalid function %s in map table\n", fname);
+ goto exit_free_buf;
+ }
+ fsel = ret;
+
+ ret = pmxops->get_function_groups(pctldev, fsel, &groups, &num_groups);
+ if (ret) {
+ dev_err(pctldev->dev, "no groups for function %d (%s)", fsel, fname);
+ goto exit_free_buf;
+ }
+
+ ret = match_string(groups, num_groups, gname);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "invalid group %s", gname);
+ goto exit_free_buf;
+ }
+
+ ret = pinctrl_get_group_selector(pctldev, gname);
+ if (ret < 0) {
+ dev_err(pctldev->dev, "failed to get group selector for %s", gname);
+ goto exit_free_buf;
+ }
+ gsel = ret;
+
+ ret = pmxops->set_mux(pctldev, fsel, gsel);
+ if (ret) {
+ dev_err(pctldev->dev, "set_mux() failed: %d", ret);
+ goto exit_free_buf;
+ }
+ ret = len;
+
+exit_free_buf:
+ kfree(buf);
+
+ return ret;
+}
+
+static int pinmux_select_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, NULL, inode->i_private);
+}
+
+static const struct file_operations pinmux_select_ops = {
+ .owner = THIS_MODULE,
+ .open = pinmux_select_open,
+ .write = pinmux_select,
+ .llseek = no_llseek,
+ .release = single_release,
+};
+
+void pinmux_init_device_debugfs(struct dentry *devroot,
+ struct pinctrl_dev *pctldev)
+{
+ debugfs_create_file("pinmux-functions", 0444,
+ devroot, pctldev, &pinmux_functions_fops);
+ debugfs_create_file("pinmux-pins", 0444,
+ devroot, pctldev, &pinmux_pins_fops);
+ debugfs_create_file("pinmux-select", 0200,
+ devroot, pctldev, &pinmux_select_ops);
+}
+
+#endif /* CONFIG_DEBUG_FS */
+
+#ifdef CONFIG_GENERIC_PINMUX_FUNCTIONS
+
+/**
+ * pinmux_generic_get_function_count() - returns number of functions
+ * @pctldev: pin controller device
+ */
+int pinmux_generic_get_function_count(struct pinctrl_dev *pctldev)
+{
+ return pctldev->num_functions;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_get_function_count);
+
+/**
+ * pinmux_generic_get_function_name() - returns the function name
+ * @pctldev: pin controller device
+ * @selector: function number
+ */
+const char *
+pinmux_generic_get_function_name(struct pinctrl_dev *pctldev,
+ unsigned int selector)
+{
+ struct function_desc *function;
+
+ function = radix_tree_lookup(&pctldev->pin_function_tree,
+ selector);
+ if (!function)
+ return NULL;
+
+ return function->name;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name);
+
+/**
+ * pinmux_generic_get_function_groups() - gets the function groups
+ * @pctldev: pin controller device
+ * @selector: function number
+ * @groups: array of pin groups
+ * @num_groups: number of pin groups
+ */
+int pinmux_generic_get_function_groups(struct pinctrl_dev *pctldev,
+ unsigned int selector,
+ const char * const **groups,
+ unsigned * const num_groups)
+{
+ struct function_desc *function;
+
+ function = radix_tree_lookup(&pctldev->pin_function_tree,
+ selector);
+ if (!function) {
+ dev_err(pctldev->dev, "%s could not find function%i\n",
+ __func__, selector);
+ return -EINVAL;
+ }
+ *groups = function->group_names;
+ *num_groups = function->num_group_names;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_get_function_groups);
+
+/**
+ * pinmux_generic_get_function() - returns a function based on the number
+ * @pctldev: pin controller device
+ * @selector: function number
+ */
+struct function_desc *pinmux_generic_get_function(struct pinctrl_dev *pctldev,
+ unsigned int selector)
+{
+ struct function_desc *function;
+
+ function = radix_tree_lookup(&pctldev->pin_function_tree,
+ selector);
+ if (!function)
+ return NULL;
+
+ return function;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_get_function);
+
+/**
+ * pinmux_generic_add_function() - adds a function group
+ * @pctldev: pin controller device
+ * @name: name of the function
+ * @groups: array of pin groups
+ * @num_groups: number of pin groups
+ * @data: pin controller driver specific data
+ */
+int pinmux_generic_add_function(struct pinctrl_dev *pctldev,
+ const char *name,
+ const char * const *groups,
+ const unsigned int num_groups,
+ void *data)
+{
+ struct function_desc *function;
+ int selector;
+
+ if (!name)
+ return -EINVAL;
+
+ selector = pinmux_func_name_to_selector(pctldev, name);
+ if (selector >= 0)
+ return selector;
+
+ selector = pctldev->num_functions;
+
+ function = devm_kzalloc(pctldev->dev, sizeof(*function), GFP_KERNEL);
+ if (!function)
+ return -ENOMEM;
+
+ function->name = name;
+ function->group_names = groups;
+ function->num_group_names = num_groups;
+ function->data = data;
+
+ radix_tree_insert(&pctldev->pin_function_tree, selector, function);
+
+ pctldev->num_functions++;
+
+ return selector;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_add_function);
+
+/**
+ * pinmux_generic_remove_function() - removes a numbered function
+ * @pctldev: pin controller device
+ * @selector: function number
+ *
+ * Note that the caller must take care of locking.
+ */
+int pinmux_generic_remove_function(struct pinctrl_dev *pctldev,
+ unsigned int selector)
+{
+ struct function_desc *function;
+
+ function = radix_tree_lookup(&pctldev->pin_function_tree,
+ selector);
+ if (!function)
+ return -ENOENT;
+
+ radix_tree_delete(&pctldev->pin_function_tree, selector);
+ devm_kfree(pctldev->dev, function);
+
+ pctldev->num_functions--;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pinmux_generic_remove_function);
+
+/**
+ * pinmux_generic_free_functions() - removes all functions
+ * @pctldev: pin controller device
+ *
+ * Note that the caller must take care of locking. The pinctrl
+ * functions are allocated with devm_kzalloc() so no need to free
+ * them here.
+ */
+void pinmux_generic_free_functions(struct pinctrl_dev *pctldev)
+{
+ struct radix_tree_iter iter;
+ void __rcu **slot;
+
+ radix_tree_for_each_slot(slot, &pctldev->pin_function_tree, &iter, 0)
+ radix_tree_delete(&pctldev->pin_function_tree, iter.index);
+
+ pctldev->num_functions = 0;
+}
+
+#endif /* CONFIG_GENERIC_PINMUX_FUNCTIONS */