[PATCH 3/3] nvmem: core: remove nvmem_mutex

From: Heiner Kallweit
Date: Sun Jun 04 2017 - 07:02:41 EST


Mutex nvmem_mutex is used in __nvmem_device_get only and isn't needed
due to:

- of_nvmem_find just calls bus_find_device which doesn't need locking
- nvmem_find_cell is protected by nvmem_cells_mutex

Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
---
drivers/nvmem/core.c | 13 ++-----------
1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 1aa6d25a..783eb431 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -55,7 +55,6 @@ struct nvmem_cell {
struct list_head node;
};

-static DEFINE_MUTEX(nvmem_mutex);
static DEFINE_IDA(nvmem_ida);

static LIST_HEAD(nvmem_cells);
@@ -538,14 +537,10 @@ static struct nvmem_device *__nvmem_device_get(struct device_node *np,
{
struct nvmem_device *nvmem = NULL;

- mutex_lock(&nvmem_mutex);
-
if (np) {
nvmem = of_nvmem_find(np);
- if (!nvmem) {
- mutex_unlock(&nvmem_mutex);
+ if (!nvmem)
return ERR_PTR(-EPROBE_DEFER);
- }
} else {
struct nvmem_cell *cell = nvmem_find_cell(cell_id);

@@ -554,14 +549,10 @@ static struct nvmem_device *__nvmem_device_get(struct device_node *np,
*cellp = cell;
}

- if (!nvmem) {
- mutex_unlock(&nvmem_mutex);
+ if (!nvmem)
return ERR_PTR(-ENOENT);
- }
}

- mutex_unlock(&nvmem_mutex);
-
if (!try_module_get(nvmem->owner)) {
dev_err(&nvmem->dev,
"could not increase module refcount for cell %s\n",
--
2.13.0