[PATCH v2 5/8] nvmem: provide consumer access to cell size metrics
From: Oleksij Rempel <o.rempel@pengutronix.de>
Date: 2024-01-24 12:22:25
Also in:
linux-pm, lkml
Subsystem:
nvmem framework, the rest · Maintainers:
Srinivas Kandagatla, Linus Torvalds
Add nvmem_cell_get_size() function to provide access to cell size metrics. In some cases we may get cell size less as consumer would expect it. So, nvmem_cell_write() would fail with incorrect buffer size. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> --- drivers/nvmem/core.c | 25 +++++++++++++++++++++++++ include/linux/nvmem-consumer.h | 7 +++++++ 2 files changed, 32 insertions(+)
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 980123fb4dde..a21e5649fcda 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c@@ -1790,6 +1790,31 @@ int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len) EXPORT_SYMBOL_GPL(nvmem_cell_write); +/** + * nvmem_cell_get_size() - Get the size of a given nvmem cell + * @cell: nvmem cell to be queried. + * @bytes: Pointer to store the size of the cell in bytes. Can be NULL. + * @bits: Pointer to store the size of the cell in bits. Can be NULL. + * + * Return: 0 on success or negative on failure. + */ +int nvmem_cell_get_size(struct nvmem_cell *cell, size_t *bytes, size_t *bits) +{ + struct nvmem_cell_entry *entry = cell->entry; + + if (!entry->nvmem) + return -EINVAL; + + if (bytes) + *bytes = entry->bytes; + + if (bits) + *bits = entry->nbits; + + return 0; +} +EXPORT_SYMBOL_GPL(nvmem_cell_get_size); + static int nvmem_cell_read_common(struct device *dev, const char *cell_id, void *val, size_t count) {
diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h
index 34c0e58dfa26..bcb0e17e415d 100644
--- a/include/linux/nvmem-consumer.h
+++ b/include/linux/nvmem-consumer.h@@ -56,6 +56,7 @@ void nvmem_cell_put(struct nvmem_cell *cell); void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell); void *nvmem_cell_read(struct nvmem_cell *cell, size_t *len); int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len); +int nvmem_cell_get_size(struct nvmem_cell *cell, size_t *bytes, size_t *bits); int nvmem_cell_read_u8(struct device *dev, const char *cell_id, u8 *val); int nvmem_cell_read_u16(struct device *dev, const char *cell_id, u16 *val); int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val);
@@ -128,6 +129,12 @@ static inline int nvmem_cell_write(struct nvmem_cell *cell, return -EOPNOTSUPP; } +static inline int nvmem_cell_get_size(struct nvmem_cell *cell, size_t *bytes, + size_t *bits) +{ + return -EOPNOTSUPP; +} + static inline int nvmem_cell_read_u8(struct device *dev, const char *cell_id, u8 *val) {
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2.39.2