aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/nvmem
diff options
context:
space:
mode:
authorLeonard Crestez <leonard.crestez@nxp.com>2017-07-26 11:34:46 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-08-28 17:33:23 +0200
commitd026d70a2e9460dc701d20b48672b80a2656006d (patch)
tree24acc74a69f48c4f163b75c9764305f19f33da68 /drivers/nvmem
parent5f214ccdd1cab5cdfbd15bf08124d456c7fd8eec (diff)
nvmem: core: Add nvmem_cell_read_u32
This function does a quick and easy read of an u32 value without any kind of resource management code on the consumer side. Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Reviewed-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/nvmem')
-rw-r--r--drivers/nvmem/core.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index b0c60338296a..72a60dc8a429 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -1111,6 +1111,43 @@ int nvmem_cell_write(struct nvmem_cell *cell, void *buf, size_t len)
EXPORT_SYMBOL_GPL(nvmem_cell_write);
/**
+ * nvmem_cell_read_u32() - Read a cell value as an u32
+ *
+ * @dev: Device that requests the nvmem cell.
+ * @cell_id: Name of nvmem cell to read.
+ * @val: pointer to output value.
+ *
+ * Return: 0 on success or negative errno.
+ */
+int nvmem_cell_read_u32(struct device *dev, const char *cell_id, u32 *val)
+{
+ struct nvmem_cell *cell;
+ void *buf;
+ size_t len;
+
+ cell = nvmem_cell_get(dev, cell_id);
+ if (IS_ERR(cell))
+ return PTR_ERR(cell);
+
+ buf = nvmem_cell_read(cell, &len);
+ if (IS_ERR(buf)) {
+ nvmem_cell_put(cell);
+ return PTR_ERR(buf);
+ }
+ if (len != sizeof(*val)) {
+ kfree(buf);
+ nvmem_cell_put(cell);
+ return -EINVAL;
+ }
+ memcpy(val, buf, sizeof(*val));
+
+ kfree(buf);
+ nvmem_cell_put(cell);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nvmem_cell_read_u32);
+
+/**
* nvmem_device_cell_read() - Read a given nvmem device and cell
*
* @nvmem: nvmem device to read from.

Privacy Policy