[PATCH v6 1/9] nvmem: Add a simple NVMEM framework for nvmem providers

Srinivas Kandagatla [off-list ref] hat am 23. Juni 2015 um
01:08 geschrieben:


[...]

--- /dev/null
+++ b/drivers/nvmem/Kconfig

@@ -0,0 +1,10 @@
+menuconfig NVMEM
+ tristate "NVMEM Support"
+ select REGMAP
+ help
+ Support for NVMEM devices.
+
+ This framework is designed to provide a generic interface to NVMEM
+ from both the Linux Kernel and the userspace.

+
+ If unsure, say no.

diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
new file mode 100644
index 0000000..6df2c69
--- /dev/null
+++ b/drivers/nvmem/Makefile

@@ -0,0 +1,6 @@
+#
+# Makefile for nvmem drivers.
+#
+
+obj-$(CONFIG_NVMEM) += nvmem_core.o
+nvmem_core-y := core.o

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
new file mode 100644
index 0000000..17a826d
--- /dev/null
+++ b/drivers/nvmem/core.c

@@ -0,0 +1,398 @@
+/*
+ * nvmem framework core.
+ *
+ * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
+ * Copyright (C) 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/nvmem-provider.h>
+#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/regmap.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>

+ [...]
+/**
+ * nvmem_register() - Register a nvmem device for given nvmem_config.
+ * Also creates an binary entry in /sys/class/nvmem/dev-name/nvmem
+ *
+ * @config: nvmem device configuration with which nvmem device is created.
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to nvmem_device.
+ */
+
+struct nvmem_device *nvmem_register(struct nvmem_config *config)
+{
+ struct nvmem_device *nvmem;
+ 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);
+ }
+
+ 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.class = &nvmem_class;
+ nvmem->dev.parent = config->dev;
+ nvmem->dev.of_node = config->dev->of_node;
+ dev_set_name(&nvmem->dev, "%s%d",
+ config->name ? : "nvmem", config->id);
+
+ nvmem->read_only = nvmem->dev.of_node ?
+ of_property_read_bool(nvmem->dev.of_node,
+ "read-only") :
+ config->read_only;
+
+ device_initialize(&nvmem->dev);
+
+ dev_dbg(&nvmem->dev, "Registering nvmem device %s\n",
+ dev_name(&nvmem->dev));
+
+ rval = device_add(&nvmem->dev);
+ if (rval) {
+ ida_simple_remove(&nvmem_ida, nvmem->id);
+ kfree(nvmem);
+ return ERR_PTR(rval);
+ }
+
+ /* update sysfs attributes */
+ if (nvmem->read_only)
+ sysfs_update_group(&nvmem->dev.kobj, &nvmem_bin_ro_group);
+
+ if (config->cells)
+ nvmem_add_cells(nvmem, config);