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User-space helpers again check the presence of the callbacks to see if they should return -EPERM. Ahead of adding SRCU synchronization: change the error code returned to in-kernel users to -EOPNOTSUPP which is more indicative of the actual reason for the failure. Move these checks into the higher-level nvmem_reg_read/write() functions to avoid calling into nvmem_access_with_keepouts() unnecessarily. Remove the checks from the sysfs attribute callbacks as these are not visible without the required callbacks. Signed-off-by: Bartosz Golaszewski --- drivers/nvmem/core.c | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index 311cb2e5a5c02d2c6979d7c9bbb7f94abdfbdad1..c18c7bb94a13b20ad27ec452a2b9fe80c2a4f843 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -55,10 +55,10 @@ static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, void *val, size_t bytes) { - if (nvmem->reg_read) - return nvmem->reg_read(nvmem->priv, offset, val, bytes); + if (!nvmem->reg_read) + return -EOPNOTSUPP; - return -EINVAL; + return nvmem->reg_read(nvmem->priv, offset, val, bytes); } static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, @@ -66,14 +66,14 @@ static int __nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset, { int ret; - if (nvmem->reg_write) { - gpiod_set_value_cansleep(nvmem->wp_gpio, 0); - ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); - gpiod_set_value_cansleep(nvmem->wp_gpio, 1); - return ret; - } + if (!nvmem->reg_write) + return -EOPNOTSUPP; + + gpiod_set_value_cansleep(nvmem->wp_gpio, 0); + ret = nvmem->reg_write(nvmem->priv, offset, val, bytes); + gpiod_set_value_cansleep(nvmem->wp_gpio, 1); - return -EINVAL; + return ret; } static int nvmem_access_with_keepouts(struct nvmem_device *nvmem, @@ -231,11 +231,7 @@ static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj, count = round_down(count, nvmem->word_size); - if (!nvmem->reg_read) - return -EPERM; - rc = nvmem_reg_read(nvmem, pos, buf, count); - if (rc) return rc; @@ -264,11 +260,10 @@ static ssize_t bin_attr_nvmem_write(struct file *filp, struct kobject *kobj, count = round_down(count, nvmem->word_size); - if (!nvmem->reg_write || nvmem->read_only) + if (nvmem->read_only) return -EPERM; rc = nvmem_reg_write(nvmem, pos, buf, count); - if (rc) return rc; -- 2.47.3