# SPDX-License-Identifier: GPL-2.0-only
menuconfig NVMEM
bool "NVMEM Support"
+ imply NVMEM_LAYOUTS
help
Support for NVMEM(Non Volatile Memory) devices like EEPROM, EFUSES...
obj-$(CONFIG_NVMEM) += nvmem_core.o
nvmem_core-y := core.o
+obj-$(CONFIG_NVMEM_LAYOUTS) += nvmem_layouts.o
+nvmem_layouts-y := layouts.o
obj-y += layouts/
# Devices
static BLOCKING_NOTIFIER_HEAD(nvmem_notifier);
-static DEFINE_SPINLOCK(nvmem_layout_lock);
-static LIST_HEAD(nvmem_layouts);
-
static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset,
void *val, size_t bytes)
{
return err;
}
-int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner)
+int nvmem_layout_register(struct nvmem_layout *layout)
{
- layout->owner = owner;
-
- spin_lock(&nvmem_layout_lock);
- list_add(&layout->node, &nvmem_layouts);
- spin_unlock(&nvmem_layout_lock);
-
- blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_ADD, layout);
+ if (!layout->add_cells)
+ return -EINVAL;
- return 0;
+ /* Populate the cells */
+ return layout->add_cells(&layout->nvmem->dev, layout->nvmem);
}
-EXPORT_SYMBOL_GPL(__nvmem_layout_register);
+EXPORT_SYMBOL_GPL(nvmem_layout_register);
void nvmem_layout_unregister(struct nvmem_layout *layout)
{
- blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_REMOVE, layout);
-
- spin_lock(&nvmem_layout_lock);
- list_del(&layout->node);
- spin_unlock(&nvmem_layout_lock);
+ /* Keep the API even with an empty stub in case we need it later */
}
EXPORT_SYMBOL_GPL(nvmem_layout_unregister);
-static struct nvmem_layout *nvmem_layout_get(struct nvmem_device *nvmem)
-{
- struct device_node *layout_np;
- struct nvmem_layout *l, *layout = ERR_PTR(-EPROBE_DEFER);
-
- layout_np = of_nvmem_layout_get_container(nvmem);
- if (!layout_np)
- return NULL;
-
- /* Fixed layouts don't have a matching driver */
- if (of_device_is_compatible(layout_np, "fixed-layout")) {
- of_node_put(layout_np);
- return NULL;
- }
-
- /*
- * In case the nvmem device was built-in while the layout was built as a
- * module, we shall manually request the layout driver loading otherwise
- * we'll never have any match.
- */
- of_request_module(layout_np);
-
- spin_lock(&nvmem_layout_lock);
-
- list_for_each_entry(l, &nvmem_layouts, node) {
- if (of_match_node(l->of_match_table, layout_np)) {
- if (try_module_get(l->owner))
- layout = l;
-
- break;
- }
- }
-
- spin_unlock(&nvmem_layout_lock);
- of_node_put(layout_np);
-
- return layout;
-}
-
-static void nvmem_layout_put(struct nvmem_layout *layout)
-{
- if (layout)
- module_put(layout->owner);
-}
-
-static int nvmem_add_cells_from_layout(struct nvmem_device *nvmem)
-{
- struct nvmem_layout *layout = nvmem->layout;
- int ret;
-
- if (layout && layout->add_cells) {
- ret = layout->add_cells(&nvmem->dev, nvmem);
- if (ret)
- return ret;
- }
-
- return 0;
-}
-
-#if IS_ENABLED(CONFIG_OF)
-struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem)
-{
- return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout");
-}
-EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container);
-#endif
-
const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem,
struct nvmem_layout *layout)
{
const struct of_device_id *match;
layout_np = of_nvmem_layout_get_container(nvmem);
- match = of_match_node(layout->of_match_table, layout_np);
+ match = of_match_node(layout->dev.driver->of_match_table, layout_np);
return match ? match->data : NULL;
}
goto err_put_device;
}
- /*
- * If the driver supplied a layout by config->layout, the module
- * pointer will be NULL and nvmem_layout_put() will be a noop.
- */
- nvmem->layout = config->layout ?: nvmem_layout_get(nvmem);
- if (IS_ERR(nvmem->layout)) {
- rval = PTR_ERR(nvmem->layout);
- nvmem->layout = NULL;
-
- if (rval == -EPROBE_DEFER)
- goto err_teardown_compat;
- }
-
if (config->cells) {
rval = nvmem_add_cells(nvmem, config->cells, config->ncells);
if (rval)
if (rval)
goto err_remove_cells;
- rval = nvmem_add_cells_from_layout(nvmem);
- if (rval)
- goto err_remove_cells;
-
dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name);
rval = device_add(&nvmem->dev);
if (rval)
goto err_remove_cells;
+ rval = nvmem_populate_layout(nvmem);
+ if (rval)
+ goto err_remove_dev;
+
blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem);
return nvmem;
+err_remove_dev:
+ device_del(&nvmem->dev);
err_remove_cells:
nvmem_device_remove_all_cells(nvmem);
- nvmem_layout_put(nvmem->layout);
-err_teardown_compat:
if (config->compat)
nvmem_sysfs_remove_compat(nvmem, config);
err_put_device:
device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);
nvmem_device_remove_all_cells(nvmem);
- nvmem_layout_put(nvmem->layout);
+ nvmem_destroy_layout(nvmem);
device_unregister(&nvmem->dev);
}
return cell;
}
+static void nvmem_layout_module_put(struct nvmem_device *nvmem)
+{
+ if (nvmem->layout && nvmem->layout->dev.driver)
+ module_put(nvmem->layout->dev.driver->owner);
+}
+
#if IS_ENABLED(CONFIG_OF)
static struct nvmem_cell_entry *
nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np)
return cell;
}
+static int nvmem_layout_module_get_optional(struct nvmem_device *nvmem)
+{
+ if (!nvmem->layout)
+ return 0;
+
+ if (!nvmem->layout->dev.driver ||
+ !try_module_get(nvmem->layout->dev.driver->owner))
+ return -EPROBE_DEFER;
+
+ return 0;
+}
+
/**
* of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id
*
return ERR_CAST(nvmem);
}
+ ret = nvmem_layout_module_get_optional(nvmem);
+ if (ret) {
+ of_node_put(cell_np);
+ __nvmem_device_put(nvmem);
+ return ERR_PTR(ret);
+ }
+
cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np);
of_node_put(cell_np);
if (!cell_entry) {
__nvmem_device_put(nvmem);
- return ERR_PTR(-ENOENT);
+ nvmem_layout_module_put(nvmem);
+ if (nvmem->layout)
+ return ERR_PTR(-EPROBE_DEFER);
+ else
+ return ERR_PTR(-ENOENT);
}
cell = nvmem_create_cell(cell_entry, id, cell_index);
- if (IS_ERR(cell))
+ if (IS_ERR(cell)) {
__nvmem_device_put(nvmem);
+ nvmem_layout_module_put(nvmem);
+ }
return cell;
}
kfree(cell);
__nvmem_device_put(nvmem);
+ nvmem_layout_module_put(nvmem);
}
EXPORT_SYMBOL_GPL(nvmem_cell_put);
static int __init nvmem_init(void)
{
- return bus_register(&nvmem_bus_type);
+ int ret;
+
+ ret = bus_register(&nvmem_bus_type);
+ if (ret)
+ return ret;
+
+ ret = nvmem_layout_bus_register();
+ if (ret)
+ bus_unregister(&nvmem_bus_type);
+
+ return ret;
}
static void __exit nvmem_exit(void)
{
+ nvmem_layout_bus_unregister();
bus_unregister(&nvmem_bus_type);
}
void *priv;
};
+#if IS_ENABLED(CONFIG_OF)
+int nvmem_layout_bus_register(void);
+void nvmem_layout_bus_unregister(void);
+int nvmem_populate_layout(struct nvmem_device *nvmem);
+void nvmem_destroy_layout(struct nvmem_device *nvmem);
+#else /* CONFIG_OF */
+static inline int nvmem_layout_bus_register(void)
+{
+ return 0;
+}
+
+static inline void nvmem_layout_bus_unregister(void) {}
+
+static inline int nvmem_populate_layout(struct nvmem_device *nvmem)
+{
+ return 0;
+}
+
+static inline void nvmem_destroy_layout(struct nvmem_device *nvmem) { }
+#endif /* CONFIG_OF */
+
#endif /* ifndef _LINUX_NVMEM_INTERNALS_H */
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMEM layout bus handling
+ *
+ * Copyright (C) 2023 Bootlin
+ * Author: Miquel Raynal <miquel.raynal@bootlin.com
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+
+#include "internals.h"
+
+#define to_nvmem_layout_driver(drv) \
+ (container_of((drv), struct nvmem_layout_driver, driver))
+#define to_nvmem_layout_device(_dev) \
+ container_of((_dev), struct nvmem_layout, dev)
+
+static int nvmem_layout_bus_match(struct device *dev, struct device_driver *drv)
+{
+ return of_driver_match_device(dev, drv);
+}
+
+static int nvmem_layout_bus_probe(struct device *dev)
+{
+ struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ if (!drv->probe || !drv->remove)
+ return -EINVAL;
+
+ return drv->probe(layout);
+}
+
+static void nvmem_layout_bus_remove(struct device *dev)
+{
+ struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ return drv->remove(layout);
+}
+
+static struct bus_type nvmem_layout_bus_type = {
+ .name = "nvmem-layout",
+ .match = nvmem_layout_bus_match,
+ .probe = nvmem_layout_bus_probe,
+ .remove = nvmem_layout_bus_remove,
+};
+
+int nvmem_layout_driver_register(struct nvmem_layout_driver *drv)
+{
+ drv->driver.bus = &nvmem_layout_bus_type;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(nvmem_layout_driver_register);
+
+void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(nvmem_layout_driver_unregister);
+
+static void nvmem_layout_release_device(struct device *dev)
+{
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ of_node_put(layout->dev.of_node);
+ kfree(layout);
+}
+
+static int nvmem_layout_create_device(struct nvmem_device *nvmem,
+ struct device_node *np)
+{
+ struct nvmem_layout *layout;
+ struct device *dev;
+ int ret;
+
+ layout = kzalloc(sizeof(*layout), GFP_KERNEL);
+ if (!layout)
+ return -ENOMEM;
+
+ /* Create a bidirectional link */
+ layout->nvmem = nvmem;
+ nvmem->layout = layout;
+
+ /* Device model registration */
+ dev = &layout->dev;
+ device_initialize(dev);
+ dev->parent = &nvmem->dev;
+ dev->bus = &nvmem_layout_bus_type;
+ dev->release = nvmem_layout_release_device;
+ dev->coherent_dma_mask = DMA_BIT_MASK(32);
+ dev->dma_mask = &dev->coherent_dma_mask;
+ device_set_node(dev, of_fwnode_handle(of_node_get(np)));
+ of_device_make_bus_id(dev);
+ of_msi_configure(dev, dev->of_node);
+
+ ret = device_add(dev);
+ if (ret) {
+ put_device(dev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_nvmem_layout_skip_table[] = {
+ { .compatible = "fixed-layout", },
+ {}
+};
+
+static int nvmem_layout_bus_populate(struct nvmem_device *nvmem,
+ struct device_node *layout_dn)
+{
+ int ret;
+
+ /* Make sure it has a compatible property */
+ if (!of_get_property(layout_dn, "compatible", NULL)) {
+ pr_debug("%s() - skipping %pOF, no compatible prop\n",
+ __func__, layout_dn);
+ return 0;
+ }
+
+ /* Fixed layouts are parsed manually somewhere else for now */
+ if (of_match_node(of_nvmem_layout_skip_table, layout_dn)) {
+ pr_debug("%s() - skipping %pOF node\n", __func__, layout_dn);
+ return 0;
+ }
+
+ if (of_node_check_flag(layout_dn, OF_POPULATED_BUS)) {
+ pr_debug("%s() - skipping %pOF, already populated\n",
+ __func__, layout_dn);
+
+ return 0;
+ }
+
+ /* NVMEM layout buses expect only a single device representing the layout */
+ ret = nvmem_layout_create_device(nvmem, layout_dn);
+ if (ret)
+ return ret;
+
+ of_node_set_flag(layout_dn, OF_POPULATED_BUS);
+
+ return 0;
+}
+
+struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem)
+{
+ return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout");
+}
+EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container);
+
+/*
+ * Returns the number of devices populated, 0 if the operation was not relevant
+ * for this nvmem device, an error code otherwise.
+ */
+int nvmem_populate_layout(struct nvmem_device *nvmem)
+{
+ struct device_node *layout_dn;
+ int ret;
+
+ layout_dn = of_nvmem_layout_get_container(nvmem);
+ if (!layout_dn)
+ return 0;
+
+ /* Populate the layout device */
+ device_links_supplier_sync_state_pause();
+ ret = nvmem_layout_bus_populate(nvmem, layout_dn);
+ device_links_supplier_sync_state_resume();
+
+ of_node_put(layout_dn);
+ return ret;
+}
+
+void nvmem_destroy_layout(struct nvmem_device *nvmem)
+{
+ struct device *dev;
+
+ if (!nvmem->layout)
+ return;
+
+ dev = &nvmem->layout->dev;
+ of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
+ device_unregister(dev);
+}
+
+int nvmem_layout_bus_register(void)
+{
+ return bus_register(&nvmem_layout_bus_type);
+}
+
+void nvmem_layout_bus_unregister(void)
+{
+ bus_unregister(&nvmem_layout_bus_type);
+}
# SPDX-License-Identifier: GPL-2.0
+config NVMEM_LAYOUTS
+ bool
+ depends on OF
+
+if NVMEM_LAYOUTS
+
menu "Layout Types"
config NVMEM_LAYOUT_SL28_VPD
If unsure, say N.
endmenu
+
+endif
return 0;
}
+static int onie_tlv_probe(struct nvmem_layout *layout)
+{
+ layout->add_cells = onie_tlv_parse_table;
+
+ return nvmem_layout_register(layout);
+}
+
+static void onie_tlv_remove(struct nvmem_layout *layout)
+{
+ nvmem_layout_unregister(layout);
+}
+
static const struct of_device_id onie_tlv_of_match_table[] = {
{ .compatible = "onie,tlv-layout", },
{},
};
MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table);
-static struct nvmem_layout onie_tlv_layout = {
- .name = "ONIE tlv layout",
- .of_match_table = onie_tlv_of_match_table,
- .add_cells = onie_tlv_parse_table,
+static struct nvmem_layout_driver onie_tlv_layout = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "onie-tlv-layout",
+ .of_match_table = onie_tlv_of_match_table,
+ },
+ .probe = onie_tlv_probe,
+ .remove = onie_tlv_remove,
};
module_nvmem_layout_driver(onie_tlv_layout);
return 0;
}
+static int sl28vpd_probe(struct nvmem_layout *layout)
+{
+ layout->add_cells = sl28vpd_add_cells;
+
+ return nvmem_layout_register(layout);
+}
+
+static void sl28vpd_remove(struct nvmem_layout *layout)
+{
+ nvmem_layout_unregister(layout);
+}
+
static const struct of_device_id sl28vpd_of_match_table[] = {
{ .compatible = "kontron,sl28-vpd" },
{},
};
MODULE_DEVICE_TABLE(of, sl28vpd_of_match_table);
-static struct nvmem_layout sl28vpd_layout = {
- .name = "sl28-vpd",
- .of_match_table = sl28vpd_of_match_table,
- .add_cells = sl28vpd_add_cells,
+static struct nvmem_layout_driver sl28vpd_layout = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "kontron-sl28vpd-layout",
+ .of_match_table = sl28vpd_of_match_table,
+ },
+ .probe = sl28vpd_probe,
+ .remove = sl28vpd_remove,
};
module_nvmem_layout_driver(sl28vpd_layout);
#ifndef _LINUX_NVMEM_PROVIDER_H
#define _LINUX_NVMEM_PROVIDER_H
+#include <linux/device.h>
#include <linux/device/driver.h>
#include <linux/err.h>
#include <linux/errno.h>
/**
* struct nvmem_layout - NVMEM layout definitions
*
- * @name: Layout name.
- * @of_match_table: Open firmware match table.
- * @add_cells: Called to populate the layout using
- * nvmem_add_one_cell().
- * @owner: Pointer to struct module.
- * @node: List node.
+ * @dev: Device-model layout device.
+ * @nvmem: The underlying NVMEM device
+ * @add_cells: Will be called if a nvmem device is found which
+ * has this layout. The function will add layout
+ * specific cells with nvmem_add_one_cell().
*
* A nvmem device can hold a well defined structure which can just be
* evaluated during runtime. For example a TLV list, or a list of "name=val"
* cells.
*/
struct nvmem_layout {
- const char *name;
- const struct of_device_id *of_match_table;
+ struct device dev;
+ struct nvmem_device *nvmem;
int (*add_cells)(struct device *dev, struct nvmem_device *nvmem);
+};
- /* private */
- struct module *owner;
- struct list_head node;
+struct nvmem_layout_driver {
+ struct device_driver driver;
+ int (*probe)(struct nvmem_layout *layout);
+ void (*remove)(struct nvmem_layout *layout);
};
#if IS_ENABLED(CONFIG_NVMEM)
int nvmem_add_one_cell(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info);
-int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner);
-#define nvmem_layout_register(layout) \
- __nvmem_layout_register(layout, THIS_MODULE)
+int nvmem_layout_register(struct nvmem_layout *layout);
void nvmem_layout_unregister(struct nvmem_layout *layout);
+int nvmem_layout_driver_register(struct nvmem_layout_driver *drv);
+void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv);
+#define module_nvmem_layout_driver(__nvmem_layout_driver) \
+ module_driver(__nvmem_layout_driver, nvmem_layout_driver_register, \
+ nvmem_layout_driver_unregister)
+
const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem,
struct nvmem_layout *layout);
#endif /* CONFIG_NVMEM && CONFIG_OF */
-#define module_nvmem_layout_driver(__layout_driver) \
- module_driver(__layout_driver, nvmem_layout_register, \
- nvmem_layout_unregister)
-
#endif /* ifndef _LINUX_NVMEM_PROVIDER_H */
projects / linux-2.6-microblaze.git / commitdiff