UPSTREAM: nvmem: add support for cell info

Add new structs and routines allowing users to define nvmem cells from
machine code. This global list of entries is parsed when a provider
is registered and cells are associated with the relevant nvmem_device
struct.

A possible improvement for the future is to allow users to register
cell tables after the nvmem provider has been registered by updating
the cell list at each call to nvmem_(add|del)_cell_table().

Bug: 154188491
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit b985f4cba6dbb3b60ad119c6f7e5cbad6f0d7e45)
Signed-off-by: Will McVicker <willmcvicker@google.com>
[willmcvicker: fix trivial merge conflicts]
Change-Id: I4070c4c5d12aa9f555e55ec1f5edccee6395ca7b
This commit is contained in:
Bartosz Golaszewski 2018-09-21 06:40:15 -07:00 committed by Will McVicker
parent ea3f6572ec
commit e96a106255
2 changed files with 97 additions and 10 deletions

View file

@ -61,6 +61,9 @@ struct nvmem_cell {
static DEFINE_MUTEX(nvmem_mutex);
static DEFINE_IDA(nvmem_ida);
static DEFINE_MUTEX(nvmem_cell_mutex);
static LIST_HEAD(nvmem_cell_tables);
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key eeprom_lock_key;
#endif
@ -478,6 +481,43 @@ static int nvmem_add_cells_from_of(struct nvmem_device *nvmem)
return 0;
}
static int nvmem_add_cells_from_table(struct nvmem_device *nvmem)
{
const struct nvmem_cell_info *info;
struct nvmem_cell_table *table;
struct nvmem_cell *cell;
int rval = 0, i;
mutex_lock(&nvmem_cell_mutex);
list_for_each_entry(table, &nvmem_cell_tables, node) {
if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) {
for (i = 0; i < table->ncells; i++) {
info = &table->cells[i];
cell = kzalloc(sizeof(*cell), GFP_KERNEL);
if (!cell) {
rval = -ENOMEM;
goto out;
}
rval = nvmem_cell_info_to_nvmem_cell(nvmem,
info,
cell);
if (rval) {
kfree(cell);
goto out;
}
nvmem_cell_add(cell);
}
}
}
out:
mutex_unlock(&nvmem_cell_mutex);
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
@ -564,12 +604,18 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
goto err_teardown_compat;
}
rval = nvmem_add_cells_from_table(nvmem);
if (rval)
goto err_remove_cells;
rval = nvmem_add_cells_from_of(nvmem);
if (rval)
goto err_teardown_compat;
goto err_remove_cells;
return nvmem;
err_remove_cells:
nvmem_device_remove_all_cells(nvmem);
err_teardown_compat:
if (config->compat)
device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);
@ -1353,6 +1399,32 @@ int nvmem_device_write(struct nvmem_device *nvmem,
}
EXPORT_SYMBOL_GPL(nvmem_device_write);
/**
* nvmem_add_cell_table() - register a table of cell info entries
*
* @table: table of cell info entries
*/
void nvmem_add_cell_table(struct nvmem_cell_table *table)
{
mutex_lock(&nvmem_cell_mutex);
list_add_tail(&table->node, &nvmem_cell_tables);
mutex_unlock(&nvmem_cell_mutex);
}
EXPORT_SYMBOL_GPL(nvmem_add_cell_table);
/**
* nvmem_del_cell_table() - remove a previously registered cell info table
*
* @table: table of cell info entries
*/
void nvmem_del_cell_table(struct nvmem_cell_table *table)
{
mutex_lock(&nvmem_cell_mutex);
list_del(&table->node);
mutex_unlock(&nvmem_cell_mutex);
}
EXPORT_SYMBOL_GPL(nvmem_del_cell_table);
/**
* nvmem_dev_name() - Get the name of a given nvmem device.
*

View file

@ -67,6 +67,25 @@ struct nvmem_config {
struct device *base_dev;
};
/**
* struct nvmem_cell_table - NVMEM cell definitions for given provider
*
* @nvmem_name: Provider name.
* @cells: Array of cell definitions.
* @ncells: Number of cell definitions in the array.
* @node: List node.
*
* This structure together with related helper functions is provided for users
* that don't can't access the nvmem provided structure but wish to register
* cell definitions for it e.g. board files registering an EEPROM device.
*/
struct nvmem_cell_table {
const char *nvmem_name;
const struct nvmem_cell_info *cells;
size_t ncells;
struct list_head node;
};
#if IS_ENABLED(CONFIG_NVMEM)
struct nvmem_device *nvmem_register(const struct nvmem_config *cfg);
@ -77,9 +96,9 @@ struct nvmem_device *devm_nvmem_register(struct device *dev,
int devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem);
int nvmem_add_cells(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info,
int ncells);
void nvmem_add_cell_table(struct nvmem_cell_table *table);
void nvmem_del_cell_table(struct nvmem_cell_table *table);
#else
static inline struct nvmem_device *nvmem_register(const struct nvmem_config *c)
@ -105,12 +124,8 @@ devm_nvmem_unregister(struct device *dev, struct nvmem_device *nvmem)
}
static inline int nvmem_add_cells(struct nvmem_device *nvmem,
const struct nvmem_cell_info *info,
int ncells)
{
return -ENOSYS;
}
static inline void nvmem_add_cell_table(struct nvmem_cell_table *table) {}
static inline void nvmem_del_cell_table(struct nvmem_cell_table *table) {}
#endif /* CONFIG_NVMEM */
#endif /* ifndef _LINUX_NVMEM_PROVIDER_H */