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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
commit8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch)
treee9891aa6c295060d065adffd610c4f49ecf884f3 /drivers/nvmem
parenta71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff)
Linux-libre 4.3.2-gnu
Diffstat (limited to 'drivers/nvmem')
-rw-r--r--drivers/nvmem/Kconfig39
-rw-r--r--drivers/nvmem/Makefile12
-rw-r--r--drivers/nvmem/core.c1083
-rw-r--r--drivers/nvmem/qfprom.c85
-rw-r--r--drivers/nvmem/sunxi_sid.c180
5 files changed, 1399 insertions, 0 deletions
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
new file mode 100644
index 000000000..8db297821
--- /dev/null
+++ b/drivers/nvmem/Kconfig
@@ -0,0 +1,39 @@
+menuconfig NVMEM
+ tristate "NVMEM Support"
+ select REGMAP
+ help
+ Support for NVMEM(Non Volatile Memory) devices like EEPROM, EFUSES...
+
+ This framework is designed to provide a generic interface to NVMEM
+ from both the Linux Kernel and the userspace.
+
+ This driver can also be built as a module. If so, the module
+ will be called nvmem_core.
+
+ If unsure, say no.
+
+if NVMEM
+
+config QCOM_QFPROM
+ tristate "QCOM QFPROM Support"
+ depends on ARCH_QCOM || COMPILE_TEST
+ select REGMAP_MMIO
+ help
+ Say y here to enable QFPROM support. The QFPROM provides access
+ functions for QFPROM data to rest of the drivers via nvmem interface.
+
+ This driver can also be built as a module. If so, the module
+ will be called nvmem_qfprom.
+
+config NVMEM_SUNXI_SID
+ tristate "Allwinner SoCs SID support"
+ depends on ARCH_SUNXI
+ select REGMAP_MMIO
+ help
+ This is a driver for the 'security ID' available on various Allwinner
+ devices.
+
+ This driver can also be built as a module. If so, the module
+ will be called nvmem_sunxi_sid.
+
+endif
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
new file mode 100644
index 000000000..4328b930a
--- /dev/null
+++ b/drivers/nvmem/Makefile
@@ -0,0 +1,12 @@
+#
+# Makefile for nvmem drivers.
+#
+
+obj-$(CONFIG_NVMEM) += nvmem_core.o
+nvmem_core-y := core.o
+
+# Devices
+obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
+nvmem_qfprom-y := qfprom.o
+obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem_sunxi_sid.o
+nvmem_sunxi_sid-y := sunxi_sid.o
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
new file mode 100644
index 000000000..6fd4e5a5e
--- /dev/null
+++ b/drivers/nvmem/core.c
@@ -0,0 +1,1083 @@
+/*
+ * nvmem framework core.
+ *
+ * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+ * Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+struct nvmem_device {
+ const char *name;
+ struct regmap *regmap;
+ struct module *owner;
+ struct device dev;
+ int stride;
+ int word_size;
+ int ncells;
+ int id;
+ int users;
+ size_t size;
+ bool read_only;
+};
+
+struct nvmem_cell {
+ const char *name;
+ int offset;
+ int bytes;
+ int bit_offset;
+ int nbits;
+ struct nvmem_device *nvmem;
+ struct list_head node;
+};
+
+static DEFINE_MUTEX(nvmem_mutex);
+static DEFINE_IDA(nvmem_ida);
+
+static LIST_HEAD(nvmem_cells);
+static DEFINE_MUTEX(nvmem_cells_mutex);
+
+#define to_nvmem_device(d) container_of(d, struct nvmem_device, dev)
+
+static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t pos, size_t count)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct nvmem_device *nvmem = to_nvmem_device(dev);
+ int rc;
+
+ /* Stop the user from reading */
+ if (pos >= nvmem->size)
+ return 0;
+
+ if (pos + count > nvmem->size)
+ count = nvmem->size - pos;
+
+ count = round_down(count, nvmem->word_size);
+
+ rc = regmap_raw_read(nvmem->regmap, pos, buf, count);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return count;
+}
+
+static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t pos, size_t count)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct nvmem_device *nvmem = to_nvmem_device(dev);
+ int rc;
+
+ /* Stop the user from writing */
+ if (pos >= nvmem->size)
+ return 0;
+
+ if (pos + count > nvmem->size)
+ count = nvmem->size - pos;
+
+ count = round_down(count, nvmem->word_size);
+
+ rc = regmap_raw_write(nvmem->regmap, pos, buf, count);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return count;
+}
+
+/* default read/write permissions */
+static struct bin_attribute bin_attr_rw_nvmem = {
+ .attr = {
+ .name = "nvmem",
+ .mode = S_IWUSR | S_IRUGO,
+ },
+ .read = bin_attr_nvmem_read,
+ .write = bin_attr_nvmem_write,
+};
+
+static struct bin_attribute *nvmem_bin_rw_attributes[] = {
+ &bin_attr_rw_nvmem,
+ NULL,
+};
+
+static const struct attribute_group nvmem_bin_rw_group = {
+ .bin_attrs = nvmem_bin_rw_attributes,
+};
+
+static const struct attribute_group *nvmem_rw_dev_groups[] = {
+ &nvmem_bin_rw_group,
+ NULL,
+};
+
+/* read only permission */
+static struct bin_attribute bin_attr_ro_nvmem = {
+ .attr = {
+ .name = "nvmem",
+ .mode = S_IRUGO,
+ },
+ .read = bin_attr_nvmem_read,
+};
+
+static struct bin_attribute *nvmem_bin_ro_attributes[] = {
+ &bin_attr_ro_nvmem,
+ NULL,
+};
+
+static const struct attribute_group nvmem_bin_ro_group = {
+ .bin_attrs = nvmem_bin_ro_attributes,
+};
+
+static const struct attribute_group *nvmem_ro_dev_groups[] = {
+ &nvmem_bin_ro_group,
+ NULL,
+};
+
+static void nvmem_release(struct device *dev)
+{
+ struct nvmem_device *nvmem = to_nvmem_device(dev);
+
+ ida_simple_remove(&nvmem_ida, nvmem->id);
+ kfree(nvmem);
+}
+
+static const struct device_type nvmem_provider_type = {
+ .release = nvmem_release,
+};
+
+static struct bus_type nvmem_bus_type = {
+ .name = "nvmem",
+};
+
+static int of_nvmem_match(struct device *dev, void *nvmem_np)
+{
+ return dev->of_node == nvmem_np;
+}
+
+static struct nvmem_device *of_nvmem_find(struct device_node *nvmem_np)
+{
+ struct device *d;
+
+ if (!nvmem_np)
+ return NULL;
+
+ d = bus_find_device(&nvmem_bus_type, NULL, nvmem_np, of_nvmem_match);
+
+ if (!d)
+ return NULL;
+
+ return to_nvmem_device(d);
+}
+
+static struct nvmem_cell *nvmem_find_cell(const char *cell_id)
+{
+ struct nvmem_cell *p;
+
+ list_for_each_entry(p, &nvmem_cells, node)
+ if (p && !strcmp(p->name, cell_id))
+ return p;
+
+ return NULL;
+}
+
+static void nvmem_cell_drop(struct nvmem_cell *cell)
+{
+ mutex_lock(&nvmem_cells_mutex);
+ list_del(&cell->node);
+ mutex_unlock(&nvmem_cells_mutex);
+ kfree(cell);
+}
+
+static void nvmem_device_remove_all_cells(const struct nvmem_device *nvmem)
+{
+ struct nvmem_cell *cell;
+ struct list_head *p, *n;
+
+ list_for_each_safe(p, n, &nvmem_cells) {
+ cell = list_entry(p, struct nvmem_cell, node);
+ if (cell->nvmem == nvmem)
+ nvmem_cell_drop(cell);
+ }
+}
+
+static void nvmem_cell_add(struct nvmem_cell *cell)
+{
+ mutex_lock(&nvmem_cells_mutex);
+ list_add_tail(&cell->node, &nvmem_cells);
+ mutex_unlock(&nvmem_cells_mutex);
+}
+
+static int nvmem_cell_info_to_nvmem_cell(struct nvmem_device *nvmem,
+ const struct nvmem_cell_info *info,
+ struct nvmem_cell *cell)
+{
+ cell->nvmem = nvmem;
+ cell->offset = info->offset;
+ cell->bytes = info->bytes;
+ cell->name = info->name;
+
+ cell->bit_offset = info->bit_offset;
+ cell->nbits = info->nbits;
+
+ if (cell->nbits)
+ cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset,
+ BITS_PER_BYTE);
+
+ if (!IS_ALIGNED(cell->offset, nvmem->stride)) {
+ dev_err(&nvmem->dev,
+ "cell %s unaligned to nvmem stride %d\n",
+ cell->name, nvmem->stride);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int nvmem_add_cells(struct nvmem_device *nvmem,
+ const struct nvmem_config *cfg)
+{
+ struct nvmem_cell **cells;
+ const struct nvmem_cell_info *info = cfg->cells;
+ int i, rval;
+
+ cells = kcalloc(cfg->ncells, sizeof(*cells), GFP_KERNEL);
+ if (!cells)
+ return -ENOMEM;
+
+ for (i = 0; i < cfg->ncells; i++) {
+ cells[i] = kzalloc(sizeof(**cells), GFP_KERNEL);
+ if (!cells[i]) {
+ rval = -ENOMEM;
+ goto err;
+ }
+
+ rval = nvmem_cell_info_to_nvmem_cell(nvmem, &info[i], cells[i]);
+ if (IS_ERR_VALUE(rval)) {
+ kfree(cells[i]);
+ goto err;
+ }
+
+ nvmem_cell_add(cells[i]);
+ }
+
+ nvmem->ncells = cfg->ncells;
+ /* remove tmp array */
+ kfree(cells);
+
+ return 0;
+err:
+ while (--i)
+ nvmem_cell_drop(cells[i]);
+
+ return rval;
+}
+
+/**
+ * nvmem_register() - Register a nvmem device for given nvmem_config.
+ * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem
+ *
+ * @config: nvmem device configuration with which nvmem device is created.
+ *
+ * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device
+ * on success.
+ */
+
+struct nvmem_device *nvmem_register(const struct nvmem_config *config)
+{
+ struct nvmem_device *nvmem;
+ struct device_node *np;
+ struct regmap *rm;
+ int rval;
+
+ if (!config->dev)
+ return ERR_PTR(-EINVAL);
+
+ rm = dev_get_regmap(config->dev, NULL);
+ if (!rm) {
+ dev_err(config->dev, "Regmap not found\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL);
+ if (!nvmem)
+ return ERR_PTR(-ENOMEM);
+
+ rval = ida_simple_get(&nvmem_ida, 0, 0, GFP_KERNEL);
+ if (rval < 0) {
+ kfree(nvmem);
+ return ERR_PTR(rval);
+ }
+
+ nvmem->id = rval;
+ nvmem->regmap = rm;
+ nvmem->owner = config->owner;
+ nvmem->stride = regmap_get_reg_stride(rm);
+ nvmem->word_size = regmap_get_val_bytes(rm);
+ nvmem->size = regmap_get_max_register(rm) + nvmem->stride;
+ nvmem->dev.type = &nvmem_provider_type;
+ nvmem->dev.bus = &nvmem_bus_type;
+ nvmem->dev.parent = config->dev;
+ np = config->dev->of_node;
+ nvmem->dev.of_node = np;
+ dev_set_name(&nvmem->dev, "%s%d",
+ config->name ? : "nvmem", config->id);
+
+ nvmem->read_only = of_property_read_bool(np, "read-only") |
+ config->read_only;
+
+ nvmem->dev.groups = nvmem->read_only ? nvmem_ro_dev_groups :
+ nvmem_rw_dev_groups;
+
+ device_initialize(&nvmem->dev);
+
+ dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name);
+
+ rval = device_add(&nvmem->dev);
+ if (rval) {
+ ida_simple_remove(&nvmem_ida, nvmem->id);
+ kfree(nvmem);
+ return ERR_PTR(rval);
+ }
+
+ if (config->cells)
+ nvmem_add_cells(nvmem, config);
+
+ return nvmem;
+}
+EXPORT_SYMBOL_GPL(nvmem_register);
+
+/**
+ * nvmem_unregister() - Unregister previously registered nvmem device
+ *
+ * @nvmem: Pointer to previously registered nvmem device.
+ *
+ * Return: Will be an negative on error or a zero on success.
+ */
+int nvmem_unregister(struct nvmem_device *nvmem)
+{
+ mutex_lock(&nvmem_mutex);
+ if (nvmem->users) {
+ mutex_unlock(&nvmem_mutex);
+ return -EBUSY;
+ }
+ mutex_unlock(&nvmem_mutex);
+
+ nvmem_device_remove_all_cells(nvmem);
+ device_del(&nvmem->dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nvmem_unregister);
+
+static struct nvmem_device *__nvmem_device_get(struct device_node *np,
+ struct nvmem_cell **cellp,
+ const char *cell_id)
+{
+ struct nvmem_device *nvmem = NULL;
+
+ mutex_lock(&nvmem_mutex);
+
+ if (np) {
+ nvmem = of_nvmem_find(np);
+ if (!nvmem) {
+ mutex_unlock(&nvmem_mutex);
+ return ERR_PTR(-EPROBE_DEFER);
+ }
+ } else {
+ struct nvmem_cell *cell = nvmem_find_cell(cell_id);
+
+ if (cell) {
+ nvmem = cell->nvmem;
+ *cellp = cell;
+ }
+
+ if (!nvmem) {
+ mutex_unlock(&nvmem_mutex);
+ return ERR_PTR(-ENOENT);
+ }
+ }
+
+ nvmem->users++;
+ mutex_unlock(&nvmem_mutex);
+
+ if (!try_module_get(nvmem->owner)) {
+ dev_err(&nvmem->dev,
+ "could not increase module refcount for cell %s\n",
+ nvmem->name);
+
+ mutex_lock(&nvmem_mutex);
+ nvmem->users--;
+ mutex_unlock(&nvmem_mutex);
+
+ return ERR_PTR(-EINVAL);
+ }
+
+ return nvmem;
+}
+
+static void __nvmem_device_put(struct nvmem_device *nvmem)
+{
+ module_put(nvmem->owner);
+ mutex_lock(&nvmem_mutex);
+ nvmem->users--;
+ mutex_unlock(&nvmem_mutex);
+}
+
+static int nvmem_match(struct device *dev, void *data)
+{
+ return !strcmp(dev_name(dev), data);
+}
+
+static struct nvmem_device *nvmem_find(const char *name)
+{
+ struct device *d;
+
+ d = bus_find_device(&nvmem_bus_type, NULL, (void *)name, nvmem_match);
+
+ if (!d)
+ return NULL;
+
+ return to_nvmem_device(d);
+}
+
+#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OF)
+/**
+ * of_nvmem_device_get() - Get nvmem device from a given id
+ *
+ * @dev node: Device tree node that uses the nvmem device
+ * @id: nvmem name from nvmem-names property.
+ *
+ * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device
+ * on success.
+ */
+struct nvmem_device *of_nvmem_device_get(struct device_node *np, const char *id)
+{
+
+ struct device_node *nvmem_np;
+ int index;
+
+ index = of_property_match_string(np, "nvmem-names", id);
+
+ nvmem_np = of_parse_phandle(np, "nvmem", index);
+ if (!nvmem_np)
+ return ERR_PTR(-EINVAL);
+
+ return __nvmem_device_get(nvmem_np, NULL, NULL);
+}
+EXPORT_SYMBOL_GPL(of_nvmem_device_get);
+#endif
+
+/**
+ * nvmem_device_get() - Get nvmem device from a given id
+ *
+ * @dev : Device that uses the nvmem device
+ * @id: nvmem name from nvmem-names property.
+ *
+ * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_device
+ * on success.
+ */
+struct nvmem_device *nvmem_device_get(struct device *dev, const char *dev_name)
+{
+ if (dev->of_node) { /* try dt first */
+ struct nvmem_device *nvmem;
+
+ nvmem = of_nvmem_device_get(dev->of_node, dev_name);
+
+ if (!IS_ERR(nvmem) || PTR_ERR(nvmem) == -EPROBE_DEFER)
+ return nvmem;
+
+ }
+
+ return nvmem_find(dev_name);
+}
+EXPORT_SYMBOL_GPL(nvmem_device_get);
+
+static int devm_nvmem_device_match(struct device *dev, void *res, void *data)
+{
+ struct nvmem_device **nvmem = res;
+
+ if (WARN_ON(!nvmem || !*nvmem))
+ return 0;
+
+ return *nvmem == data;
+}
+
+static void devm_nvmem_device_release(struct device *dev, void *res)
+{
+ nvmem_device_put(*(struct nvmem_device **)res);
+}
+
+/**
+ * devm_nvmem_device_put() - put alredy got nvmem device
+ *
+ * @nvmem: pointer to nvmem device allocated by devm_nvmem_cell_get(),
+ * that needs to be released.
+ */
+void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem)
+{
+ int ret;
+
+ ret = devres_release(dev, devm_nvmem_device_release,
+ devm_nvmem_device_match, nvmem);
+
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL_GPL(devm_nvmem_device_put);
+
+/**
+ * nvmem_device_put() - put alredy got nvmem device
+ *
+ * @nvmem: pointer to nvmem device that needs to be released.
+ */
+void nvmem_device_put(struct nvmem_device *nvmem)
+{
+ __nvmem_device_put(nvmem);
+}
+EXPORT_SYMBOL_GPL(nvmem_device_put);
+
+/**
+ * devm_nvmem_device_get() - Get nvmem cell of device form a given id
+ *
+ * @dev node: Device tree node that uses the nvmem cell
+ * @id: nvmem name in nvmems property.
+ *
+ * Return: ERR_PTR() on error or a valid pointer to a struct nvmem_cell
+ * on success. The nvmem_cell will be freed by the automatically once the
+ * device is freed.
+ */
+struct nvmem_device *devm_nvmem_device_get(struct device *dev, const char *id)
+{
+ struct nvmem_device **ptr, *nvmem;
+
+ ptr = devres_alloc(devm_nvmem_device_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ nvmem = nvmem_device_get(dev, id);
+ if (!IS_ERR(nvmem)) {
+ *ptr = nvmem;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return nvmem;
+}
+EXPORT_SYMBOL_GPL(devm_nvmem_device_get);
+
+static struct nvmem_cell *nvmem_cell_get_from_list(const char *cell_id)
+{
+ struct nvmem_cell *cell = NULL;
+ struct nvmem_device *nvmem;
+
+ nvmem = __nvmem_device_get(NULL, &cell, cell_id);
+ if (IS_ERR(nvmem))
+ return ERR_CAST(nvmem);
+
+ return cell;
+}
+
+#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OF)
+/**
+ * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id
+ *
+ * @dev node: Device tree node that uses the nvmem cell
+ * @id: nvmem cell name from nvmem-cell-names property.
+ *
+ * Return: Will be an ERR_PTR() on error or a valid pointer
+ * to a struct nvmem_cell. The nvmem_cell will be freed by the
+ * nvmem_cell_put().
+ */
+struct nvmem_cell *of_nvmem_cell_get(struct device_node *np,
+ const char *name)
+{
+ struct device_node *cell_np, *nvmem_np;
+ struct nvmem_cell *cell;
+ struct nvmem_device *nvmem;
+ const __be32 *addr;
+ int rval, len, index;
+
+ index = of_property_match_string(np, "nvmem-cell-names", name);
+
+ cell_np = of_parse_phandle(np, "nvmem-cells", index);
+ if (!cell_np)
+ return ERR_PTR(-EINVAL);
+
+ nvmem_np = of_get_next_parent(cell_np);
+ if (!nvmem_np)
+ return ERR_PTR(-EINVAL);
+
+ nvmem = __nvmem_device_get(nvmem_np, NULL, NULL);
+ if (IS_ERR(nvmem))
+ return ERR_CAST(nvmem);
+
+ addr = of_get_property(cell_np, "reg", &len);
+ if (!addr || (len < 2 * sizeof(u32))) {
+ dev_err(&nvmem->dev, "nvmem: invalid reg on %s\n",
+ cell_np->full_name);
+ rval = -EINVAL;
+ goto err_mem;
+ }
+
+ cell = kzalloc(sizeof(*cell), GFP_KERNEL);
+ if (!cell) {
+ rval = -ENOMEM;
+ goto err_mem;
+ }
+
+ cell->nvmem = nvmem;
+ cell->offset = be32_to_cpup(addr++);
+ cell->bytes = be32_to_cpup(addr);
+ cell->name = cell_np->name;
+
+ addr = of_get_property(cell_np, "bits", &len);
+ if (addr && len == (2 * sizeof(u32))) {
+ cell->bit_offset = be32_to_cpup(addr++);
+ cell->nbits = be32_to_cpup(addr);
+ }
+
+ if (cell->nbits)
+ cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset,
+ BITS_PER_BYTE);
+
+ if (!IS_ALIGNED(cell->offset, nvmem->stride)) {
+ dev_err(&nvmem->dev,
+ "cell %s unaligned to nvmem stride %d\n",
+ cell->name, nvmem->stride);
+ rval = -EINVAL;
+ goto err_sanity;
+ }
+
+ nvmem_cell_add(cell);
+
+ return cell;
+
+err_sanity:
+ kfree(cell);
+
+err_mem:
+ __nvmem_device_put(nvmem);
+
+ return ERR_PTR(rval);
+}
+EXPORT_SYMBOL_GPL(of_nvmem_cell_get);
+#endif
+
+/**
+ * nvmem_cell_get() - Get nvmem cell of device form a given cell name
+ *
+ * @dev node: Device tree node that uses the nvmem cell
+ * @id: nvmem cell name to get.
+ *
+ * Return: Will be an ERR_PTR() on error or a valid pointer
+ * to a struct nvmem_cell. The nvmem_cell will be freed by the
+ * nvmem_cell_put().
+ */
+struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *cell_id)
+{
+ struct nvmem_cell *cell;
+
+ if (dev->of_node) { /* try dt first */
+ cell = of_nvmem_cell_get(dev->of_node, cell_id);
+ if (!IS_ERR(cell) || PTR_ERR(cell) == -EPROBE_DEFER)
+ return cell;
+ }
+
+ return nvmem_cell_get_from_list(cell_id);
+}
+EXPORT_SYMBOL_GPL(nvmem_cell_get);
+
+static void devm_nvmem_cell_release(struct device *dev, void *res)
+{
+ nvmem_cell_put(*(struct nvmem_cell **)res);
+}
+
+/**
+ * devm_nvmem_cell_get() - Get nvmem cell of device form a given id
+ *
+ * @dev node: Device tree node that uses the nvmem cell
+ * @id: nvmem id in nvmem-names property.
+ *
+ * Return: Will be an ERR_PTR() on error or a valid pointer
+ * to a struct nvmem_cell. The nvmem_cell will be freed by the
+ * automatically once the device is freed.
+ */
+struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *id)
+{
+ struct nvmem_cell **ptr, *cell;
+
+ ptr = devres_alloc(devm_nvmem_cell_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ cell = nvmem_cell_get(dev, id);
+ if (!IS_ERR(cell)) {
+ *ptr = cell;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return cell;
+}
+EXPORT_SYMBOL_GPL(devm_nvmem_cell_get);
+
+static int devm_nvmem_cell_match(struct device *dev, void *res, void *data)
+{
+ struct nvmem_cell **c = res;
+
+ if (WARN_ON(!c || !*c))
+ return 0;
+
+ return *c == data;
+}
+
+/**
+ * devm_nvmem_cell_put() - Release previously allocated nvmem cell
+ * from devm_nvmem_cell_get.
+ *
+ * @cell: Previously allocated nvmem cell by devm_nvmem_cell_get()
+ */
+void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell)
+{
+ int ret;
+
+ ret = devres_release(dev, devm_nvmem_cell_release,
+ devm_nvmem_cell_match, cell);
+
+ WARN_ON(ret);
+}
+EXPORT_SYMBOL(devm_nvmem_cell_put);
+
+/**
+ * nvmem_cell_put() - Release previously allocated nvmem cell.
+ *
+ * @cell: Previously allocated nvmem cell by nvmem_cell_get()
+ */
+void nvmem_cell_put(struct nvmem_cell *cell)
+{
+ struct nvmem_device *nvmem = cell->nvmem;
+
+ __nvmem_device_put(nvmem);
+ nvmem_cell_drop(cell);
+}
+EXPORT_SYMBOL_GPL(nvmem_cell_put);
+
+static inline void nvmem_shift_read_buffer_in_place(struct nvmem_cell *cell,
+ void *buf)
+{
+ u8 *p, *b;
+ int i, bit_offset = cell->bit_offset;
+
+ p = b = buf;
+ if (bit_offset) {
+ /* First shift */
+ *b++ >>= bit_offset;
+
+ /* setup rest of the bytes if any */
+ for (i = 1; i < cell->bytes; i++) {
+ /* Get bits from next byte and shift them towards msb */
+ *p |= *b << (BITS_PER_BYTE - bit_offset);
+
+ p = b;
+ *b++ >>= bit_offset;
+ }
+
+ /* result fits in less bytes */
+ if (cell->bytes != DIV_ROUND_UP(cell->nbits, BITS_PER_BYTE))
+ *p-- = 0;
+ }
+ /* clear msb bits if any leftover in the last byte */
+ *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);
+}
+
+static int __nvmem_cell_read(struct nvmem_device *nvmem,
+ struct nvmem_cell *cell,
+ void *buf, size_t *len)
+{
+ int rc;
+
+ rc = regmap_raw_read(nvmem->regmap, cell->offset, buf, cell->bytes);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ /* shift bits in-place */
+ if (cell->bit_offset || cell->nbits)
+ nvmem_shift_read_buffer_in_place(cell, buf);
+
+ *len = cell->bytes;
+
+ return 0;
+}
+
+/**
+ * nvmem_cell_read() - Read a given nvmem cell
+ *
+ * @cell: nvmem cell to be read.
+ * @len: pointer to length of cell which will be populated on successful read.
+ *
+ * Return: ERR_PTR() on error or a valid pointer to a char * buffer on success.
+ * The buffer should be freed by the consumer with a kfree().
+ */
+void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len)
+{
+ struct nvmem_device *nvmem = cell->nvmem;
+ u8 *buf;
+ int rc;
+
+ if (!nvmem || !nvmem->regmap)
+ return ERR_PTR(-EINVAL);
+
+ buf = kzalloc(cell->bytes, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ rc = __nvmem_cell_read(nvmem, cell, buf, len);
+ if (IS_ERR_VALUE(rc)) {
+ kfree(buf);
+ return ERR_PTR(rc);
+ }
+
+ return buf;
+}
+EXPORT_SYMBOL_GPL(nvmem_cell_read);
+
+static inline void *nvmem_cell_prepare_write_buffer(struct nvmem_cell *cell,
+ u8 *_buf, int len)
+{
+ struct nvmem_device *nvmem = cell->nvmem;
+ int i, rc, nbits, bit_offset = cell->bit_offset;
+ u8 v, *p, *buf, *b, pbyte, pbits;
+
+ nbits = cell->nbits;
+ buf = kzalloc(cell->bytes, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(buf, _buf, len);
+ p = b = buf;
+
+ if (bit_offset) {
+ pbyte = *b;
+ *b <<= bit_offset;
+
+ /* setup the first byte with lsb bits from nvmem */
+ rc = regmap_raw_read(nvmem->regmap, cell->offset, &v, 1);
+ *b++ |= GENMASK(bit_offset - 1, 0) & v;
+
+ /* setup rest of the byte if any */
+ for (i = 1; i < cell->bytes; i++) {
+ /* Get last byte bits and shift them towards lsb */
+ pbits = pbyte >> (BITS_PER_BYTE - 1 - bit_offset);
+ pbyte = *b;
+ p = b;
+ *b <<= bit_offset;
+ *b++ |= pbits;
+ }
+ }
+
+ /* if it's not end on byte boundary */
+ if ((nbits + bit_offset) % BITS_PER_BYTE) {
+ /* setup the last byte with msb bits from nvmem */
+ rc = regmap_raw_read(nvmem->regmap,
+ cell->offset + cell->bytes - 1, &v, 1);
+ *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v;
+
+ }
+
+ return buf;
+}
+
+/**
+ * nvmem_cell_write() - Write to a given nvmem cell
+ *
+ * @cell: nvmem cell to be written.
+ * @buf: Buffer to be written.
+ * @len: length of buffer to be written to nvmem cell.
+ *
+ * Return: length of bytes written or negative on failure.
+ */
+int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len)
+{
+ struct nvmem_device *nvmem = cell->nvmem;
+ int rc;
+
+ if (!nvmem || !nvmem->regmap || nvmem->read_only ||
+ (cell->bit_offset == 0 && len != cell->bytes))
+ return -EINVAL;
+
+ if (cell->bit_offset || cell->nbits) {
+ buf = nvmem_cell_prepare_write_buffer(cell, buf, len);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+ }
+
+ rc = regmap_raw_write(nvmem->regmap, cell->offset, buf, cell->bytes);
+
+ /* free the tmp buffer */
+ if (cell->bit_offset || cell->nbits)
+ kfree(buf);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(nvmem_cell_write);
+
+/**
+ * nvmem_device_cell_read() - Read a given nvmem device and cell
+ *
+ * @nvmem: nvmem device to read from.
+ * @info: nvmem cell info to be read.
+ * @buf: buffer pointer which will be populated on successful read.
+ *
+ * Return: length of successful bytes read on success and negative
+ * error code on error.
+ */
+ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *info, void *buf)
+{
+ struct nvmem_cell cell;
+ int rc;
+ ssize_t len;
+
+ if (!nvmem || !nvmem->regmap)
+ return -EINVAL;
+
+ rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell);
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ rc = __nvmem_cell_read(nvmem, &cell, buf, &len);
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(nvmem_device_cell_read);
+
+/**
+ * nvmem_device_cell_write() - Write cell to a given nvmem device
+ *
+ * @nvmem: nvmem device to be written to.
+ * @info: nvmem cell info to be written
+ * @buf: buffer to be written to cell.
+ *
+ * Return: length of bytes written or negative error code on failure.
+ * */
+int nvmem_device_cell_write(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *info, void *buf)
+{
+ struct nvmem_cell cell;
+ int rc;
+
+ if (!nvmem || !nvmem->regmap)
+ return -EINVAL;
+
+ rc = nvmem_cell_info_to_nvmem_cell(nvmem, info, &cell);
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return nvmem_cell_write(&cell, buf, cell.bytes);
+}
+EXPORT_SYMBOL_GPL(nvmem_device_cell_write);
+
+/**
+ * nvmem_device_read() - Read from a given nvmem device
+ *
+ * @nvmem: nvmem device to read from.
+ * @offset: offset in nvmem device.
+ * @bytes: number of bytes to read.
+ * @buf: buffer pointer which will be populated on successful read.
+ *
+ * Return: length of successful bytes read on success and negative
+ * error code on error.
+ */
+int nvmem_device_read(struct nvmem_device *nvmem,
+ unsigned int offset,
+ size_t bytes, void *buf)
+{
+ int rc;
+
+ if (!nvmem || !nvmem->regmap)
+ return -EINVAL;
+
+ rc = regmap_raw_read(nvmem->regmap, offset, buf, bytes);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(nvmem_device_read);
+
+/**
+ * nvmem_device_write() - Write cell to a given nvmem device
+ *
+ * @nvmem: nvmem device to be written to.
+ * @offset: offset in nvmem device.
+ * @bytes: number of bytes to write.
+ * @buf: buffer to be written.
+ *
+ * Return: length of bytes written or negative error code on failure.
+ * */
+int nvmem_device_write(struct nvmem_device *nvmem,
+ unsigned int offset,
+ size_t bytes, void *buf)
+{
+ int rc;
+
+ if (!nvmem || !nvmem->regmap)
+ return -EINVAL;
+
+ rc = regmap_raw_write(nvmem->regmap, offset, buf, bytes);
+
+ if (IS_ERR_VALUE(rc))
+ return rc;
+
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(nvmem_device_write);
+
+static int __init nvmem_init(void)
+{
+ return bus_register(&nvmem_bus_type);
+}
+
+static void __exit nvmem_exit(void)
+{
+ bus_unregister(&nvmem_bus_type);
+}
+
+subsys_initcall(nvmem_init);
+module_exit(nvmem_exit);
+
+MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com");
+MODULE_DESCRIPTION("nvmem Driver Core");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
new file mode 100644
index 000000000..afb67e7ee
--- /dev/null
+++ b/drivers/nvmem/qfprom.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+static struct regmap_config qfprom_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 8,
+ .reg_stride = 1,
+};
+
+static struct nvmem_config econfig = {
+ .name = "qfprom",
+ .owner = THIS_MODULE,
+};
+
+static int qfprom_remove(struct platform_device *pdev)
+{
+ struct nvmem_device *nvmem = platform_get_drvdata(pdev);
+
+ return nvmem_unregister(nvmem);
+}
+
+static int qfprom_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct nvmem_device *nvmem;
+ struct regmap *regmap;
+ void __iomem *base;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ qfprom_regmap_config.max_register = resource_size(res) - 1;
+
+ regmap = devm_regmap_init_mmio(dev, base, &qfprom_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(dev, "regmap init failed\n");
+ return PTR_ERR(regmap);
+ }
+ econfig.dev = dev;
+ nvmem = nvmem_register(&econfig);
+ if (IS_ERR(nvmem))
+ return PTR_ERR(nvmem);
+
+ platform_set_drvdata(pdev, nvmem);
+
+ return 0;
+}
+
+static const struct of_device_id qfprom_of_match[] = {
+ { .compatible = "qcom,qfprom",},
+ {/* sentinel */},
+};
+MODULE_DEVICE_TABLE(of, qfprom_of_match);
+
+static struct platform_driver qfprom_driver = {
+ .probe = qfprom_probe,
+ .remove = qfprom_remove,
+ .driver = {
+ .name = "qcom,qfprom",
+ .of_match_table = qfprom_of_match,
+ },
+};
+module_platform_driver(qfprom_driver);
+MODULE_AUTHOR("Srinivas Kandagatla <srinivas.kandagatla@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm QFPROM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c
new file mode 100644
index 000000000..cfa3b8506
--- /dev/null
+++ b/drivers/nvmem/sunxi_sid.c
@@ -0,0 +1,180 @@
+/*
+ * Allwinner sunXi SoCs Security ID support.
+ *
+ * Copyright (c) 2013 Oliver Schinagl <oliver@schinagl.nl>
+ * Copyright (C) 2014 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+
+
+static struct nvmem_config econfig = {
+ .name = "sunxi-sid",
+ .read_only = true,
+ .owner = THIS_MODULE,
+};
+
+struct sunxi_sid {
+ void __iomem *base;
+};
+
+/* We read the entire key, due to a 32 bit read alignment requirement. Since we
+ * want to return the requested byte, this results in somewhat slower code and
+ * uses 4 times more reads as needed but keeps code simpler. Since the SID is
+ * only very rarely probed, this is not really an issue.
+ */
+static u8 sunxi_sid_read_byte(const struct sunxi_sid *sid,
+ const unsigned int offset)
+{
+ u32 sid_key;
+
+ sid_key = ioread32be(sid->base + round_down(offset, 4));
+ sid_key >>= (offset % 4) * 8;
+
+ return sid_key; /* Only return the last byte */
+}
+
+static int sunxi_sid_read(void *context,
+ const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ struct sunxi_sid *sid = context;
+ unsigned int offset = *(u32 *)reg;
+ u8 *buf = val;
+
+ while (val_size) {
+ *buf++ = sunxi_sid_read_byte(sid, offset);
+ val_size--;
+ offset++;
+ }
+
+ return 0;
+}
+
+static int sunxi_sid_write(void *context, const void *data, size_t count)
+{
+ /* Unimplemented, dummy to keep regmap core happy */
+ return 0;
+}
+
+static struct regmap_bus sunxi_sid_bus = {
+ .read = sunxi_sid_read,
+ .write = sunxi_sid_write,
+ .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
+ .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
+};
+
+static bool sunxi_sid_writeable_reg(struct device *dev, unsigned int reg)
+{
+ return false;
+}
+
+static struct regmap_config sunxi_sid_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 8,
+ .reg_stride = 1,
+ .writeable_reg = sunxi_sid_writeable_reg,
+};
+
+static int sunxi_sid_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct nvmem_device *nvmem;
+ struct regmap *regmap;
+ struct sunxi_sid *sid;
+ int ret, i, size;
+ char *randomness;
+
+ sid = devm_kzalloc(dev, sizeof(*sid), GFP_KERNEL);
+ if (!sid)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sid->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(sid->base))
+ return PTR_ERR(sid->base);
+
+ size = resource_size(res) - 1;
+ sunxi_sid_regmap_config.max_register = size;
+
+ regmap = devm_regmap_init(dev, &sunxi_sid_bus, sid,
+ &sunxi_sid_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(dev, "regmap init failed\n");
+ return PTR_ERR(regmap);
+ }
+
+ econfig.dev = dev;
+ nvmem = nvmem_register(&econfig);
+ if (IS_ERR(nvmem))
+ return PTR_ERR(nvmem);
+
+ randomness = kzalloc(sizeof(u8) * size, GFP_KERNEL);
+ if (!randomness) {
+ ret = -EINVAL;
+ goto err_unreg_nvmem;
+ }
+
+ for (i = 0; i < size; i++)
+ randomness[i] = sunxi_sid_read_byte(sid, i);
+
+ add_device_randomness(randomness, size);
+ kfree(randomness);
+
+ platform_set_drvdata(pdev, nvmem);
+
+ return 0;
+
+err_unreg_nvmem:
+ nvmem_unregister(nvmem);
+ return ret;
+}
+
+static int sunxi_sid_remove(struct platform_device *pdev)
+{
+ struct nvmem_device *nvmem = platform_get_drvdata(pdev);
+
+ return nvmem_unregister(nvmem);
+}
+
+static const struct of_device_id sunxi_sid_of_match[] = {
+ { .compatible = "allwinner,sun4i-a10-sid" },
+ { .compatible = "allwinner,sun7i-a20-sid" },
+ {/* sentinel */},
+};
+MODULE_DEVICE_TABLE(of, sunxi_sid_of_match);
+
+static struct platform_driver sunxi_sid_driver = {
+ .probe = sunxi_sid_probe,
+ .remove = sunxi_sid_remove,
+ .driver = {
+ .name = "eeprom-sunxi-sid",
+ .of_match_table = sunxi_sid_of_match,
+ },
+};
+module_platform_driver(sunxi_sid_driver);
+
+MODULE_AUTHOR("Oliver Schinagl <oliver@schinagl.nl>");
+MODULE_DESCRIPTION("Allwinner sunxi security id driver");
+MODULE_LICENSE("GPL");