Add samsung specific changes

drivers/base/regmap/qti-regmap-debugfs.c

@@ -0,0 +1,695 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2011 Wolfson Microelectronics plc
+ * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/qti-regmap-debugfs.h>
+
+#include "internal.h"
+
+struct regmap_qti_debugfs {
+	struct list_head	list;
+	struct regmap		*regmap;
+	struct device		*dev;
+	unsigned int		dump_address;
+	unsigned int		dump_count;
+};
+
+static DEFINE_MUTEX(regmap_qti_debugfs_lock);
+static LIST_HEAD(regmap_qti_debugfs_list);
+
+static size_t regmap_calc_reg_len(int max_val)
+{
+	return snprintf(NULL, 0, "%x", max_val);
+}
+
+static inline void regmap_calc_tot_len(struct regmap *map,
+				       void *buf, size_t count)
+{
+	/* Calculate the length of a fixed format  */
+	if (!map->debugfs_tot_len) {
+		map->debugfs_reg_len = regmap_calc_reg_len(map->max_register),
+		map->debugfs_val_len = 2 * map->format.val_bytes;
+		map->debugfs_tot_len = map->debugfs_reg_len +
+			map->debugfs_val_len + 3;      /* : \n */
+	}
+}
+
+static bool _regmap_volatile(struct regmap *map, unsigned int reg);
+
+static int _regcache_read(struct regmap *map,
+		  unsigned int reg, unsigned int *value)
+{
+	if (map->cache_type == REGCACHE_NONE)
+		return -ENODEV;
+
+	if (WARN_ON(!map->cache_ops))
+		return -EINVAL;
+
+	if (!_regmap_volatile(map, reg))
+		return map->cache_ops->read(map, reg, value);
+
+	return -EINVAL;
+}
+
+static bool _regmap_cached(struct regmap *map, unsigned int reg)
+{
+	int ret;
+	unsigned int val;
+
+	if (map->cache_type == REGCACHE_NONE)
+		return false;
+
+	if (!map->cache_ops)
+		return false;
+
+	if (map->max_register && reg > map->max_register)
+		return false;
+
+	map->lock(map->lock_arg);
+	ret = _regcache_read(map, reg, &val);
+	map->unlock(map->lock_arg);
+	if (ret)
+		return false;
+
+	return true;
+}
+
+static bool _regmap_readable(struct regmap *map, unsigned int reg)
+{
+	if (!map->reg_read)
+		return false;
+
+	if (map->max_register && reg > map->max_register)
+		return false;
+
+	if (map->format.format_write)
+		return false;
+
+	if (map->readable_reg)
+		return map->readable_reg(map->dev, reg);
+
+	if (map->rd_table)
+		return regmap_check_range_table(map, reg, map->rd_table);
+
+	return true;
+}
+
+static bool _regmap_volatile(struct regmap *map, unsigned int reg)
+{
+	if (!map->format.format_write && !_regmap_readable(map, reg))
+		return false;
+
+	if (map->volatile_reg)
+		return map->volatile_reg(map->dev, reg);
+
+	if (map->volatile_table)
+		return regmap_check_range_table(map, reg, map->volatile_table);
+
+	if (map->cache_ops)
+		return false;
+	else
+		return true;
+}
+
+static bool _regmap_precious(struct regmap *map, unsigned int reg)
+{
+	if (!_regmap_readable(map, reg))
+		return false;
+
+	if (map->precious_reg)
+		return map->precious_reg(map->dev, reg);
+
+	if (map->precious_table)
+		return regmap_check_range_table(map, reg, map->precious_table);
+
+	return false;
+}
+
+static bool regmap_printable(struct regmap *map, unsigned int reg)
+{
+	if (_regmap_precious(map, reg))
+		return false;
+
+	if (!_regmap_readable(map, reg) && !_regmap_cached(map, reg))
+		return false;
+
+	return true;
+}
+
+static void regmap_debugfs_free_dump_cache(struct regmap *map)
+{
+	struct regmap_debugfs_off_cache *c;
+
+	while (!list_empty(&map->debugfs_off_cache)) {
+		c = list_first_entry(&map->debugfs_off_cache,
+				     struct regmap_debugfs_off_cache,
+				     list);
+		list_del(&c->list);
+		kfree(c);
+	}
+}
+
+static int regmap_next_readable_reg(struct regmap *map, int reg)
+{
+	struct regmap_debugfs_off_cache *c;
+	int ret = -EINVAL;
+
+	if (regmap_printable(map, reg + map->reg_stride)) {
+		ret = reg + map->reg_stride;
+	} else {
+		mutex_lock(&map->cache_lock);
+		list_for_each_entry(c, &map->debugfs_off_cache, list) {
+			if (reg > c->max_reg)
+				continue;
+			if (reg < c->base_reg) {
+				ret = c->base_reg;
+				break;
+			}
+		}
+		mutex_unlock(&map->cache_lock);
+	}
+	return ret;
+}
+
+static int regmap_debugfs_generate_cache(struct regmap *map)
+{
+	struct regmap_debugfs_off_cache *c = NULL;
+	loff_t p = 0;
+	unsigned int i = 0;
+
+	mutex_lock(&map->cache_lock);
+
+	if (list_empty(&map->debugfs_off_cache)) {
+		for (i = 0; i <= map->max_register; i += map->reg_stride) {
+			/* Skip unprinted registers, closing off cache entry */
+			if (!regmap_printable(map, i)) {
+				if (c) {
+					c->max = p - 1;
+					c->max_reg = i - map->reg_stride;
+					list_add_tail(&c->list,
+						      &map->debugfs_off_cache);
+					c = NULL;
+				}
+
+				continue;
+			}
+
+			/* No cache entry?  Start a new one */
+			if (!c) {
+				c = kzalloc(sizeof(*c), GFP_KERNEL);
+				if (!c) {
+					regmap_debugfs_free_dump_cache(map);
+					mutex_unlock(&map->cache_lock);
+					return -ENOMEM;
+				}
+				c->min = p;
+				c->base_reg = i;
+			}
+
+			p += map->debugfs_tot_len;
+		}
+	}
+
+	/* Close the last entry off if we didn't scan beyond it */
+	if (c) {
+		c->max = p - 1;
+		c->max_reg = i - map->reg_stride;
+		list_add_tail(&c->list,
+			      &map->debugfs_off_cache);
+	}
+
+	mutex_unlock(&map->cache_lock);
+
+	return 0;
+}
+
+/*
+ * Work out where the start offset maps into register numbers, bearing
+ * in mind that we suppress hidden registers.
+ */
+static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
+						  unsigned int base,
+						  loff_t from,
+						  loff_t *pos)
+{
+	struct regmap_debugfs_off_cache *c = NULL;
+	unsigned int ret;
+	unsigned int fpos_offset;
+	unsigned int reg_offset;
+
+	/* Suppress the cache if we're using a subrange */
+	if (base)
+		return base;
+
+	/*
+	 * If we don't have a cache build one so we don't have to do a
+	 * linear scan each time.
+	 */
+	if (regmap_debugfs_generate_cache(map) < 0)
+		return base;
+
+	mutex_lock(&map->cache_lock);
+	/*
+	 * This should never happen; we return above if we fail to
+	 * allocate and we should never be in this code if there are
+	 * no registers at all.
+	 */
+	WARN_ON(list_empty(&map->debugfs_off_cache));
+	ret = base;
+
+	/* Find the relevant block:offset */
+	list_for_each_entry(c, &map->debugfs_off_cache, list) {
+		if (from >= c->min && from <= c->max) {
+			fpos_offset = from - c->min;
+			reg_offset = fpos_offset / map->debugfs_tot_len;
+			*pos = c->min + (reg_offset * map->debugfs_tot_len);
+			mutex_unlock(&map->cache_lock);
+			return c->base_reg + (reg_offset * map->reg_stride);
+		}
+
+		*pos = c->max;
+		ret = c->max_reg;
+	}
+	mutex_unlock(&map->cache_lock);
+
+	return ret;
+}
+
+/* Determine the file offset where a register appears */
+static int regmap_debugfs_get_reg_offset(struct regmap *map,
+					 unsigned int reg,
+					 loff_t *pos)
+{
+	struct regmap_debugfs_off_cache *c = NULL;
+	unsigned int reg_offset;
+	int ret;
+
+	regmap_calc_tot_len(map, NULL, 0);
+	ret = regmap_debugfs_generate_cache(map);
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&map->cache_lock);
+	list_for_each_entry(c, &map->debugfs_off_cache, list) {
+		if (reg >= c->base_reg && reg <= c->max_reg) {
+			reg_offset = (reg - c->base_reg) / map->reg_stride;
+			*pos = c->min + (reg_offset * map->debugfs_tot_len);
+			mutex_unlock(&map->cache_lock);
+			return 0;
+		}
+	}
+	mutex_unlock(&map->cache_lock);
+
+	return -EINVAL;
+}
+
+static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from,
+				   unsigned int to, char __user *user_buf,
+				   size_t count, loff_t *ppos)
+{
+	size_t buf_pos = 0;
+	loff_t p = *ppos;
+	ssize_t ret;
+	int i;
+	char *buf;
+	unsigned int val, start_reg;
+
+	if (*ppos < 0 || !count)
+		return -EINVAL;
+
+	if (count > (PAGE_SIZE << (MAX_ORDER - 1)))
+		count = PAGE_SIZE << (MAX_ORDER - 1);
+
+	buf = kzalloc(count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	regmap_calc_tot_len(map, buf, count);
+
+	/* Work out which register we're starting at */
+	start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p);
+
+	for (i = start_reg; i >= 0 && i <= to;
+	     i = regmap_next_readable_reg(map, i)) {
+
+		/* If we're in the region the user is trying to read */
+		if (p >= *ppos) {
+			/* ...but not beyond it */
+			if (buf_pos + map->debugfs_tot_len > count)
+				break;
+
+			/* Format the register */
+			scnprintf(buf + buf_pos, count - buf_pos, "%.*x: ",
+				  map->debugfs_reg_len, i - from);
+			buf_pos += map->debugfs_reg_len + 2;
+
+			/* Format the value, write all X if we can't read */
+			ret = regmap_read(map, i, &val);
+			if (ret == 0)
+				scnprintf(buf + buf_pos, count - buf_pos,
+					  "%.*x", map->debugfs_val_len, val);
+			else
+				memset(buf + buf_pos, 'X',
+				       map->debugfs_val_len);
+			buf_pos += 2 * map->format.val_bytes;
+
+			buf[buf_pos++] = '\n';
+		}
+		p += map->debugfs_tot_len;
+	}
+
+	ret = buf_pos;
+
+	if (copy_to_user(user_buf, buf, buf_pos)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	*ppos += buf_pos;
+
+out:
+	kfree(buf);
+	return ret;
+}
+
+static ssize_t regmap_data_read_file(struct file *file, char __user *user_buf,
+				    size_t count, loff_t *ppos)
+{
+	struct regmap_qti_debugfs *debug_map = file->private_data;
+	loff_t reg_pos = 0;
+	unsigned int max_reg;
+	ssize_t ret;
+
+	ret = regmap_debugfs_get_reg_offset(debug_map->regmap,
+					    debug_map->dump_address, &reg_pos);
+	if (ret < 0)
+		return ret;
+
+	/* Treat the file position of dump_address as 0 */
+	*ppos += reg_pos;
+	max_reg = debug_map->dump_address +
+		  (debug_map->dump_count ? (debug_map->dump_count - 1) : 0) *
+		  (debug_map->regmap->reg_stride ?: 1);
+
+	ret = regmap_read_debugfs(debug_map->regmap, 0, max_reg, user_buf,
+				  count, ppos);
+	if (*ppos < reg_pos)
+		return -EINVAL;
+	*ppos -= reg_pos;
+
+	return ret;
+}
+
+#ifdef CONFIG_REGMAP_QTI_DEBUGFS_ALLOW_WRITE
+
+static ssize_t regmap_data_write_file(struct file *file,
+				     const char __user *user_buf,
+				     size_t count, loff_t *ppos)
+{
+	char buf[32];
+	size_t buf_size;
+	char *start = buf;
+	unsigned long value;
+	struct regmap_qti_debugfs *debug_map = file->private_data;
+	int ret;
+
+	buf_size = min(count, (sizeof(buf)-1));
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+	buf[buf_size] = 0;
+
+	while (*start == ' ')
+		start++;
+
+	if (kstrtoul(start, 16, &value))
+		return -EINVAL;
+
+	/* Userspace has been fiddling around behind the kernel's back */
+	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+
+	ret = regmap_write(debug_map->regmap, debug_map->dump_address, value);
+	if (ret < 0)
+		return ret;
+
+	return buf_size;
+}
+
+#define QTI_DEBUGFS_FILE_MODE 0600
+
+#else
+
+#define regmap_data_write_file NULL
+#define QTI_DEBUGFS_FILE_MODE 0400
+
+#endif
+
+static const struct file_operations regmap_data_fops = {
+	.open = simple_open,
+	.read = regmap_data_read_file,
+	.write = regmap_data_write_file,
+	.llseek = default_llseek,
+};
+
+/**
+ * regmap_qti_debugfs_add() - register extra debugfs files for a regmap
+ * @dev:		Device pointer of regmap owner
+ * @regmap:		regmap pointer
+ *
+ * This function adds various debugfs files for the specified regmap which
+ * provide a mechanism for userspace to read and write regmap register values
+ * with easy.
+ *
+ * Returns a valid pointer on success or ERR_PTR() on failure.
+ */
+static struct regmap_qti_debugfs *regmap_qti_debugfs_add(struct device *dev,
+							 struct regmap *regmap)
+{
+	struct regmap_qti_debugfs *debug_map = NULL;
+
+	if (!dev || !regmap) {
+		pr_err("%s: dev or regmap is NULL\n", __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	mutex_lock(&regmap_qti_debugfs_lock);
+	list_for_each_entry(debug_map, &regmap_qti_debugfs_list, list) {
+		if (debug_map->regmap == regmap) {
+			debug_map = ERR_PTR(-EINVAL);
+			dev_err(dev, "%s: qti debugfs files already registered for regmap\n",
+				__func__);
+			goto done;
+		}
+	}
+
+	debug_map = kzalloc(sizeof(*debug_map), GFP_KERNEL);
+	if (!debug_map) {
+		debug_map = ERR_PTR(-ENOMEM);
+		goto done;
+	}
+
+	debug_map->dev = dev;
+	debug_map->regmap = regmap;
+	debug_map->dump_count = 1;
+
+	list_add(&debug_map->list, &regmap_qti_debugfs_list);
+
+	debugfs_create_x32("address", 0600, regmap->debugfs,
+			   &debug_map->dump_address);
+
+	debugfs_create_u32("count", 0600, regmap->debugfs,
+			   &debug_map->dump_count);
+
+	debugfs_create_file_unsafe("data", QTI_DEBUGFS_FILE_MODE,
+				regmap->debugfs, debug_map, &regmap_data_fops);
+
+done:
+	mutex_unlock(&regmap_qti_debugfs_lock);
+
+	return debug_map;
+}
+
+/**
+ * regmap_qti_debugfs_register() - register extra debugfs files for a regmap
+ * @dev:		Device pointer of regmap owner
+ * @regmap:		regmap pointer
+ *
+ * This function calls regmap_qti_debugfs_add() which adds several debugfs files
+ * for the specified regmap which allow for userspace register read and write
+ * access.
+ *
+ * Returns 0 on success or an errno on failure.
+ */
+int regmap_qti_debugfs_register(struct device *dev, struct regmap *regmap)
+{
+	return PTR_ERR_OR_ZERO(regmap_qti_debugfs_add(dev, regmap));
+}
+EXPORT_SYMBOL(regmap_qti_debugfs_register);
+
+/* regmap_qti_debugfs_lock must be held by caller. */
+static void regmap_qti_debugfs_remove(struct regmap_qti_debugfs *debug_map)
+{
+	struct dentry *file;
+
+	file = debugfs_lookup("address", debug_map->regmap->debugfs);
+	dput(file);
+	debugfs_remove(file);
+
+	file = debugfs_lookup("count", debug_map->regmap->debugfs);
+	dput(file);
+	debugfs_remove(file);
+
+	file = debugfs_lookup("data", debug_map->regmap->debugfs);
+	dput(file);
+	debugfs_remove(file);
+
+	list_del(&debug_map->list);
+	kfree(debug_map);
+}
+
+/**
+ * regmap_qti_debugfs_unregister() - remove extra debugfs files associated with
+ *				     a regmap
+ * @regmap:		regmap pointer
+ *
+ * This function removes the extra debugfs files registered for 'regmap' and
+ * then frees the regmap debug resources.
+ */
+void regmap_qti_debugfs_unregister(struct regmap *regmap)
+{
+	struct regmap_qti_debugfs *debug_map, *temp;
+
+	if (IS_ERR_OR_NULL(regmap)) {
+		pr_err("%s: invalid regmap pointer\n", __func__);
+		return;
+	}
+
+	mutex_lock(&regmap_qti_debugfs_lock);
+	list_for_each_entry_safe(debug_map, temp, &regmap_qti_debugfs_list,
+				 list) {
+		if (debug_map->regmap == regmap) {
+			regmap_qti_debugfs_remove(debug_map);
+			break;
+		}
+	}
+	mutex_unlock(&regmap_qti_debugfs_lock);
+}
+EXPORT_SYMBOL(regmap_qti_debugfs_unregister);
+
+/* regmap_qti_debugfs_lock must be held by caller. */
+static void _devm_regmap_qti_debugfs_release(struct device *dev, void *res)
+{
+	struct regmap_qti_debugfs *debug_map, *temp;
+	bool found = false;
+
+	debug_map = *(struct regmap_qti_debugfs **)res;
+	list_for_each_entry(temp, &regmap_qti_debugfs_list, list) {
+		if (temp == debug_map) {
+			found = true;
+			break;
+		}
+	}
+
+	if (found)
+		regmap_qti_debugfs_remove(debug_map);
+}
+
+static void devm_regmap_qti_debugfs_release(struct device *dev, void *res)
+{
+	mutex_lock(&regmap_qti_debugfs_lock);
+	_devm_regmap_qti_debugfs_release(dev, res);
+	mutex_unlock(&regmap_qti_debugfs_lock);
+}
+
+/**
+ * devm_regmap_qti_debugfs_register() - resource managed version of
+ *					regmap_qti_debugfs_register()
+ * @dev:		Device pointer of regmap owner
+ * @regmap:		regmap pointer
+ *
+ * This is a resource managed version of regmap_qti_debugfs_register().
+ * The debugfs files added via this call are automatically removed on driver
+ * detach.
+ *
+ * Returns 0 on success or an errno on failure.
+ */
+int devm_regmap_qti_debugfs_register(struct device *dev, struct regmap *regmap)
+{
+	struct regmap_qti_debugfs *debug_map;
+	struct regmap_qti_debugfs **ptr;
+
+	ptr = devres_alloc(devm_regmap_qti_debugfs_release, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	debug_map = regmap_qti_debugfs_add(dev, regmap);
+	if (IS_ERR(debug_map)) {
+		devres_free(ptr);
+		return PTR_ERR(debug_map);
+	}
+
+	*ptr = debug_map;
+	devres_add(dev, ptr);
+
+	return 0;
+}
+EXPORT_SYMBOL(devm_regmap_qti_debugfs_register);
+
+static int devm_regmap_qti_debugfs_match(struct device *dev, void *res,
+					 void *data)
+{
+	struct regmap_qti_debugfs **debug_map = res;
+
+	if (!debug_map || !*debug_map) {
+		WARN_ON(!debug_map || !*debug_map);
+		return 0;
+	}
+
+	return *debug_map == data;
+}
+
+/**
+ * devm_regmap_qti_debugfs_unregister() - resource managed version of
+ *					  regmap_qti_debugfs_unregister()
+ * @regmap:		regmap pointer
+ *
+ * Deallocate the debug regmap data allocated for 'regmap' with
+ * devm_regmap_qti_debugfs_register().  Normally this function will not
+ * need to be called and the resource management code will ensure that the
+ * resource is freed.
+ */
+void devm_regmap_qti_debugfs_unregister(struct regmap *regmap)
+{
+	struct regmap_qti_debugfs *debug_map, *temp;
+
+	if (IS_ERR_OR_NULL(regmap)) {
+		pr_err("%s: invalid regmap pointer\n", __func__);
+		return;
+	}
+
+	mutex_lock(&regmap_qti_debugfs_lock);
+	list_for_each_entry_safe(debug_map, temp, &regmap_qti_debugfs_list,
+				 list) {
+		if (debug_map->regmap == regmap)
+			devres_release(debug_map->dev,
+				_devm_regmap_qti_debugfs_release,
+				devm_regmap_qti_debugfs_match, debug_map);
+	}
+	mutex_unlock(&regmap_qti_debugfs_lock);
+}
+EXPORT_SYMBOL(devm_regmap_qti_debugfs_unregister);
+
+MODULE_DESCRIPTION("Regmap QTI debugfs library");
+MODULE_LICENSE("GPL");