Re: [PATCH v8 1/9] nvmem: Add a simple NVMEM framework for nvmem providers
From: Stephen Boyd <hidden>
Date: 2015-07-20 21:11:51
Also in:
linux-arm-kernel, linux-arm-msm, linux-devicetree, lkml
On 07/20/2015 07:43 AM, Srinivas Kandagatla wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c new file mode 100644 index 0000000..bde5528 --- /dev/null +++ b/drivers/nvmem/core.c@@ -0,0 +1,384 @@ + +static int nvmem_add_cells(struct nvmem_device *nvmem, + const struct nvmem_config *cfg) +{ + struct nvmem_cell **cells; + const struct nvmem_cell_info *info = cfg->cells; + int i, rval; + + cells = kzalloc(sizeof(*cells) * cfg->ncells, GFP_KERNEL);
kcalloc?
+ if (!cells)
+ return -ENOMEM;
+
+ for (i = 0; i < cfg->ncells; i++) {
+ cells[i] = kzalloc(sizeof(**cells), GFP_KERNEL);
+ if (!cells[i]) {
+ rval = -ENOMEM;
+ goto err;
+ }
+
+ rval = nvmem_cell_info_to_nvmem_cell(nvmem, &info[i], cells[i]);
+ if (IS_ERR_VALUE(rval)) {
+ kfree(cells[i]);
+ goto err;
+ }
+
+ nvmem_cell_add(cells[i]);
+ }
+
+ nvmem->ncells = cfg->ncells;
+ /* remove tmp array */
+ kfree(cells);
+
+ return 0;
+err:
+ while (--i)
+ nvmem_cell_drop(cells[i]);
+
+ 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
+ *
+ * @config: nvmem device configuration with which nvmem device is created.
+ *
+ * Return: Will be an ERR_PTR() on error or a valid pointer to nvmem_device
+ * on success.
+ */
+Why the newline?
+struct nvmem_device *nvmem_register(const struct nvmem_config *config)
+{
+ struct nvmem_device *nvmem;
+ struct device_node *np;
+ struct regmap *rm;
+ int rval;
+
+ if (!config->dev)
+ return ERR_PTR(-EINVAL);
+
+ rm = dev_get_regmap(config->dev, NULL);
+ if (!rm) {
+ dev_err(config->dev, "Regmap not found\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ nvmem = kzalloc(sizeof(*nvmem), GFP_KERNEL);
+ if (!nvmem)
+ return ERR_PTR(-ENOMEM);
+
+ nvmem->id = ida_simple_get(&nvmem_ida, 0, 0, GFP_KERNEL);
+ if (nvmem->id < 0) {
+ kfree(nvmem);
+ return ERR_PTR(nvmem->id);Oops, we already freed nvmem.
+ } + + nvmem->regmap = rm; + nvmem->owner = config->owner; + nvmem->stride = regmap_get_reg_stride(rm); + nvmem->word_size = regmap_get_val_bytes(rm); + nvmem->size = regmap_get_max_register(rm) + nvmem->stride; + nvmem->dev.type = &nvmem_provider_type; + nvmem->dev.bus = &nvmem_bus_type; + nvmem->dev.parent = config->dev; + np = config->dev->of_node; + nvmem->dev.of_node = np; + dev_set_name(&nvmem->dev, "%s%d", + config->name ? : "nvmem", config->id); + + nvmem->read_only = np ? of_property_read_bool(np, "read-only") : 0;
of_property_read_bool(NULL, ..) "does the right thing" and returns false already.
+
+ nvmem->read_only |= config->read_only;
+
+ device_initialize(&nvmem->dev);
+
+ dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name);
+
+ rval = device_add(&nvmem->dev);
+ if (rval) {
+ ida_simple_remove(&nvmem_ida, nvmem->id);
+ kfree(nvmem);
+ return ERR_PTR(rval);
+ }
+
+ if (device_create_bin_file(&nvmem->dev,
+ nvmem->read_only ? &bin_attr_ro_nvmem :
+ &bin_attr_rw_nvmem))
+ dev_warn(&nvmem->dev, "Failed to create sysfs binary file\n");Why can't we have device_add() add the binary file attribute too?
+
+ if (config->cells)
+ nvmem_add_cells(nvmem, config);
+
+ return nvmem;
+}
+EXPORT_SYMBOL_GPL(nvmem_register);
+
+/**
+ * nvmem_unregister() - Unregister previously registered nvmem device
+ *
+ * @nvmem: Pointer to previously registered nvmem device.
+ *
+ * Return: Will be an negative on error or a zero on success.
+ */
+int nvmem_unregister(struct nvmem_device *nvmem)
+{
+ mutex_lock(&nvmem_mutex);
+ if (nvmem->users) {
+ mutex_unlock(&nvmem_mutex);
+ return -EBUSY;
+ }
+ mutex_unlock(&nvmem_mutex);This lock doesn't seem to be doing anything in this patch? Perhaps it should be added in the second patch where consumers start making it useful? -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project