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![John Crispin](/assets/img/avatar_default.png)
pinmux_map_to_setting() uses setting->data.mux.func/group to store the return code of pinmux_func_name_to_selector/pinctrl_get_group_selector(). However, struct pinctrl_setting_mux defines these elements as unsigned, resulting in all error codes getting lost. The conditionals following the assignments will always evaluate to false thus breaking the error paths. This bug can be triggered by loading a pinmux group map from the devicetree with an invalid function/group string. Signed-off-by: John Crispin <blogic@openwrt.org> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
633 lines
16 KiB
C
633 lines
16 KiB
C
/*
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* Core driver for the pin muxing portions of the pin control subsystem
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*
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* Copyright (C) 2011-2012 ST-Ericsson SA
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* Written on behalf of Linaro for ST-Ericsson
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* Based on bits of regulator core, gpio core and clk core
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*
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* Author: Linus Walleij <linus.walleij@linaro.org>
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*
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* Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
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*
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* License terms: GNU General Public License (GPL) version 2
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*/
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#define pr_fmt(fmt) "pinmux core: " fmt
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/device.h>
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#include <linux/slab.h>
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#include <linux/radix-tree.h>
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#include <linux/err.h>
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#include <linux/list.h>
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#include <linux/string.h>
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#include <linux/sysfs.h>
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#include <linux/debugfs.h>
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#include <linux/seq_file.h>
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#include <linux/pinctrl/machine.h>
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#include <linux/pinctrl/pinmux.h>
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#include "core.h"
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#include "pinmux.h"
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int pinmux_check_ops(struct pinctrl_dev *pctldev)
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{
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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unsigned nfuncs;
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unsigned selector = 0;
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/* Check that we implement required operations */
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if (!ops ||
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!ops->get_functions_count ||
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!ops->get_function_name ||
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!ops->get_function_groups ||
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!ops->enable ||
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!ops->disable)
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return -EINVAL;
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/* Check that all functions registered have names */
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nfuncs = ops->get_functions_count(pctldev);
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while (selector < nfuncs) {
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const char *fname = ops->get_function_name(pctldev,
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selector);
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if (!fname) {
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dev_err(pctldev->dev, "pinmux ops has no name for function%u\n",
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selector);
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return -EINVAL;
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}
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selector++;
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}
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return 0;
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}
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int pinmux_validate_map(struct pinctrl_map const *map, int i)
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{
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if (!map->data.mux.function) {
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pr_err("failed to register map %s (%d): no function given\n",
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map->name, i);
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return -EINVAL;
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}
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return 0;
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}
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/**
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* pin_request() - request a single pin to be muxed in, typically for GPIO
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* @pin: the pin number in the global pin space
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* @owner: a representation of the owner of this pin; typically the device
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* name that controls its mux function, or the requested GPIO name
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* @gpio_range: the range matching the GPIO pin if this is a request for a
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* single GPIO pin
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*/
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static int pin_request(struct pinctrl_dev *pctldev,
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int pin, const char *owner,
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struct pinctrl_gpio_range *gpio_range)
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{
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struct pin_desc *desc;
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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int status = -EINVAL;
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desc = pin_desc_get(pctldev, pin);
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if (desc == NULL) {
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dev_err(pctldev->dev,
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"pin is not registered so it cannot be requested\n");
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goto out;
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}
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dev_dbg(pctldev->dev, "request pin %d (%s) for %s\n",
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pin, desc->name, owner);
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if (gpio_range) {
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/* There's no need to support multiple GPIO requests */
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if (desc->gpio_owner) {
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dev_err(pctldev->dev,
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"pin already requested\n");
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goto out;
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}
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desc->gpio_owner = owner;
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} else {
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if (desc->mux_usecount && strcmp(desc->mux_owner, owner)) {
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dev_err(pctldev->dev,
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"pin already requested\n");
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goto out;
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}
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desc->mux_usecount++;
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if (desc->mux_usecount > 1)
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return 0;
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desc->mux_owner = owner;
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}
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/* Let each pin increase references to this module */
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if (!try_module_get(pctldev->owner)) {
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dev_err(pctldev->dev,
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"could not increase module refcount for pin %d\n",
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pin);
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status = -EINVAL;
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goto out_free_pin;
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}
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/*
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* If there is no kind of request function for the pin we just assume
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* we got it by default and proceed.
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*/
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if (gpio_range && ops->gpio_request_enable)
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/* This requests and enables a single GPIO pin */
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status = ops->gpio_request_enable(pctldev, gpio_range, pin);
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else if (ops->request)
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status = ops->request(pctldev, pin);
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else
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status = 0;
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if (status) {
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dev_err(pctldev->dev, "->request on device %s failed for pin %d\n",
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pctldev->desc->name, pin);
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module_put(pctldev->owner);
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}
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out_free_pin:
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if (status) {
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if (gpio_range) {
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desc->gpio_owner = NULL;
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} else {
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desc->mux_usecount--;
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if (!desc->mux_usecount)
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desc->mux_owner = NULL;
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}
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}
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out:
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if (status)
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dev_err(pctldev->dev, "pin-%d (%s) status %d\n",
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pin, owner, status);
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return status;
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}
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/**
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* pin_free() - release a single muxed in pin so something else can be muxed
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* @pctldev: pin controller device handling this pin
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* @pin: the pin to free
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* @gpio_range: the range matching the GPIO pin if this is a request for a
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* single GPIO pin
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*
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* This function returns a pointer to the previous owner. This is used
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* for callers that dynamically allocate an owner name so it can be freed
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* once the pin is free. This is done for GPIO request functions.
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*/
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static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
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struct pinctrl_gpio_range *gpio_range)
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{
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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struct pin_desc *desc;
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const char *owner;
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desc = pin_desc_get(pctldev, pin);
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if (desc == NULL) {
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dev_err(pctldev->dev,
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"pin is not registered so it cannot be freed\n");
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return NULL;
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}
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if (!gpio_range) {
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desc->mux_usecount--;
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if (desc->mux_usecount)
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return NULL;
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}
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/*
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* If there is no kind of request function for the pin we just assume
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* we got it by default and proceed.
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*/
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if (gpio_range && ops->gpio_disable_free)
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ops->gpio_disable_free(pctldev, gpio_range, pin);
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else if (ops->free)
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ops->free(pctldev, pin);
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if (gpio_range) {
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owner = desc->gpio_owner;
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desc->gpio_owner = NULL;
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} else {
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owner = desc->mux_owner;
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desc->mux_owner = NULL;
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desc->mux_setting = NULL;
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}
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module_put(pctldev->owner);
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return owner;
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}
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/**
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* pinmux_request_gpio() - request pinmuxing for a GPIO pin
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* @pctldev: pin controller device affected
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* @pin: the pin to mux in for GPIO
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* @range: the applicable GPIO range
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*/
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int pinmux_request_gpio(struct pinctrl_dev *pctldev,
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struct pinctrl_gpio_range *range,
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unsigned pin, unsigned gpio)
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{
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char gpiostr[16];
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const char *owner;
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int ret;
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/* Conjure some name stating what chip and pin this is taken by */
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snprintf(gpiostr, 15, "%s:%d", range->name, gpio);
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owner = kstrdup(gpiostr, GFP_KERNEL);
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if (!owner)
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return -EINVAL;
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ret = pin_request(pctldev, pin, owner, range);
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if (ret < 0)
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kfree(owner);
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return ret;
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}
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/**
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* pinmux_free_gpio() - release a pin from GPIO muxing
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* @pctldev: the pin controller device for the pin
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* @pin: the affected currently GPIO-muxed in pin
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* @range: applicable GPIO range
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*/
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void pinmux_free_gpio(struct pinctrl_dev *pctldev, unsigned pin,
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struct pinctrl_gpio_range *range)
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{
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const char *owner;
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owner = pin_free(pctldev, pin, range);
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kfree(owner);
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}
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/**
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* pinmux_gpio_direction() - set the direction of a single muxed-in GPIO pin
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* @pctldev: the pin controller handling this pin
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* @range: applicable GPIO range
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* @pin: the affected GPIO pin in this controller
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* @input: true if we set the pin as input, false for output
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*/
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int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
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struct pinctrl_gpio_range *range,
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unsigned pin, bool input)
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{
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const struct pinmux_ops *ops;
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int ret;
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ops = pctldev->desc->pmxops;
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if (ops->gpio_set_direction)
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ret = ops->gpio_set_direction(pctldev, range, pin, input);
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else
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ret = 0;
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return ret;
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}
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static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
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const char *function)
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{
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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unsigned nfuncs = ops->get_functions_count(pctldev);
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unsigned selector = 0;
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/* See if this pctldev has this function */
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while (selector < nfuncs) {
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const char *fname = ops->get_function_name(pctldev,
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selector);
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if (!strcmp(function, fname))
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return selector;
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selector++;
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}
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pr_err("%s does not support function %s\n",
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pinctrl_dev_get_name(pctldev), function);
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return -EINVAL;
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}
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int pinmux_map_to_setting(struct pinctrl_map const *map,
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struct pinctrl_setting *setting)
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{
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struct pinctrl_dev *pctldev = setting->pctldev;
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const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
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const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
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char const * const *groups;
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unsigned num_groups;
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int ret;
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const char *group;
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int i;
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const unsigned *pins;
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unsigned num_pins;
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if (!pmxops) {
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dev_err(pctldev->dev, "does not support mux function\n");
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return -EINVAL;
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}
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ret = pinmux_func_name_to_selector(pctldev, map->data.mux.function);
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if (ret < 0)
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return ret;
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setting->data.mux.func = ret;
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ret = pmxops->get_function_groups(pctldev, setting->data.mux.func,
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&groups, &num_groups);
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if (ret < 0)
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return ret;
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if (!num_groups)
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return -EINVAL;
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if (map->data.mux.group) {
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bool found = false;
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group = map->data.mux.group;
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for (i = 0; i < num_groups; i++) {
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if (!strcmp(group, groups[i])) {
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found = true;
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break;
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}
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}
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if (!found)
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return -EINVAL;
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} else {
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group = groups[0];
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}
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ret = pinctrl_get_group_selector(pctldev, group);
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if (ret < 0)
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return ret;
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setting->data.mux.group = ret;
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ret = pctlops->get_group_pins(pctldev, setting->data.mux.group, &pins,
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&num_pins);
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if (ret) {
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dev_err(pctldev->dev,
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"could not get pins for device %s group selector %d\n",
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pinctrl_dev_get_name(pctldev), setting->data.mux.group);
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return -ENODEV;
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}
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/* Try to allocate all pins in this group, one by one */
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for (i = 0; i < num_pins; i++) {
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ret = pin_request(pctldev, pins[i], map->dev_name, NULL);
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if (ret) {
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dev_err(pctldev->dev,
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"could not get request pin %d on device %s\n",
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pins[i], pinctrl_dev_get_name(pctldev));
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/* On error release all taken pins */
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i--; /* this pin just failed */
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for (; i >= 0; i--)
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pin_free(pctldev, pins[i], NULL);
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return -ENODEV;
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}
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}
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return 0;
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}
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void pinmux_free_setting(struct pinctrl_setting const *setting)
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{
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struct pinctrl_dev *pctldev = setting->pctldev;
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const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
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const unsigned *pins;
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unsigned num_pins;
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int ret;
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int i;
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ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
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&pins, &num_pins);
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if (ret) {
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dev_err(pctldev->dev,
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"could not get pins for device %s group selector %d\n",
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pinctrl_dev_get_name(pctldev), setting->data.mux.group);
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return;
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}
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for (i = 0; i < num_pins; i++)
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pin_free(pctldev, pins[i], NULL);
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}
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int pinmux_enable_setting(struct pinctrl_setting const *setting)
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{
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struct pinctrl_dev *pctldev = setting->pctldev;
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const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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int ret;
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const unsigned *pins;
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unsigned num_pins;
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int i;
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struct pin_desc *desc;
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ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
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&pins, &num_pins);
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if (ret) {
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/* errors only affect debug data, so just warn */
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dev_warn(pctldev->dev,
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"could not get pins for group selector %d\n",
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setting->data.mux.group);
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num_pins = 0;
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}
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for (i = 0; i < num_pins; i++) {
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desc = pin_desc_get(pctldev, pins[i]);
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if (desc == NULL) {
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dev_warn(pctldev->dev,
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"could not get pin desc for pin %d\n",
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pins[i]);
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continue;
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}
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desc->mux_setting = &(setting->data.mux);
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}
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return ops->enable(pctldev, setting->data.mux.func,
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setting->data.mux.group);
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}
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void pinmux_disable_setting(struct pinctrl_setting const *setting)
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{
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struct pinctrl_dev *pctldev = setting->pctldev;
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const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
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const struct pinmux_ops *ops = pctldev->desc->pmxops;
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int ret;
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const unsigned *pins;
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unsigned num_pins;
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int i;
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struct pin_desc *desc;
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ret = pctlops->get_group_pins(pctldev, setting->data.mux.group,
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&pins, &num_pins);
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if (ret) {
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/* errors only affect debug data, so just warn */
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dev_warn(pctldev->dev,
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"could not get pins for group selector %d\n",
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setting->data.mux.group);
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num_pins = 0;
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}
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for (i = 0; i < num_pins; i++) {
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desc = pin_desc_get(pctldev, pins[i]);
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if (desc == NULL) {
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dev_warn(pctldev->dev,
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"could not get pin desc for pin %d\n",
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pins[i]);
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continue;
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}
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desc->mux_setting = NULL;
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}
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ops->disable(pctldev, setting->data.mux.func, setting->data.mux.group);
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}
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#ifdef CONFIG_DEBUG_FS
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/* Called from pincontrol core */
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static int pinmux_functions_show(struct seq_file *s, void *what)
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{
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struct pinctrl_dev *pctldev = s->private;
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const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
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unsigned nfuncs;
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unsigned func_selector = 0;
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if (!pmxops)
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return 0;
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mutex_lock(&pinctrl_mutex);
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nfuncs = pmxops->get_functions_count(pctldev);
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while (func_selector < nfuncs) {
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const char *func = pmxops->get_function_name(pctldev,
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func_selector);
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const char * const *groups;
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unsigned num_groups;
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int ret;
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int i;
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ret = pmxops->get_function_groups(pctldev, func_selector,
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&groups, &num_groups);
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if (ret)
|
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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++;
|
|
}
|
|
|
|
mutex_unlock(&pinctrl_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");
|
|
seq_puts(s, "Format: pin (name): mux_owner gpio_owner hog?\n");
|
|
|
|
mutex_lock(&pinctrl_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;
|
|
|
|
seq_printf(s, "pin %d (%s): %s %s%s", pin,
|
|
desc->name ? desc->name : "unnamed",
|
|
desc->mux_owner ? desc->mux_owner
|
|
: "(MUX UNCLAIMED)",
|
|
desc->gpio_owner ? desc->gpio_owner
|
|
: "(GPIO UNCLAIMED)",
|
|
is_hog ? " (HOG)" : "");
|
|
|
|
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_printf(s, "\n");
|
|
}
|
|
|
|
mutex_unlock(&pinctrl_mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void pinmux_show_map(struct seq_file *s, struct pinctrl_map const *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,
|
|
struct pinctrl_setting const *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);
|
|
}
|
|
|
|
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 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,
|
|
};
|
|
|
|
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);
|
|
}
|
|
|
|
#endif /* CONFIG_DEBUG_FS */
|