This adds initial regmap support. Function prototypes are from the Kernel, the implemention is mostly rewritten. Currently the regmap support is limited to the bare minimum to get started. Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> --- drivers/base/Makefile | 1 + drivers/base/regmap/Makefile | 1 + drivers/base/regmap/internal.h | 18 ++ drivers/base/regmap/regmap.c | 398 +++++++++++++++++++++++++++++++++++++++++ include/regmap.h | 62 +++++++ 5 files changed, 480 insertions(+) create mode 100644 drivers/base/regmap/Makefile create mode 100644 drivers/base/regmap/internal.h create mode 100644 drivers/base/regmap/regmap.c create mode 100644 include/regmap.h diff --git a/drivers/base/Makefile b/drivers/base/Makefile index e1f1c7a..4bd4217 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -2,3 +2,4 @@ obj-y += bus.o obj-y += driver.o obj-y += platform.o obj-y += resource.o +obj-y += regmap/ \ No newline at end of file diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile new file mode 100644 index 0000000..4dc3d8c --- /dev/null +++ b/drivers/base/regmap/Makefile @@ -0,0 +1 @@ +obj-y += regmap.o \ No newline at end of file diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h new file mode 100644 index 0000000..52df529 --- /dev/null +++ b/drivers/base/regmap/internal.h @@ -0,0 +1,18 @@ + +#include <linux/list.h> + +struct regmap { + struct device_d *dev; + const struct regmap_bus *bus; + const char *name; + void *bus_context; + struct list_head list; + int reg_bits; + int reg_stride; + int pad_bits; + int val_bits; + int val_bytes; + unsigned int max_register; + + struct cdev cdev; +}; \ No newline at end of file diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c new file mode 100644 index 0000000..b626f9a --- /dev/null +++ b/drivers/base/regmap/regmap.c @@ -0,0 +1,398 @@ +/* + * Register map access API + * + * Copyright 2016 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> + * + * based on Kernel code: + * + * Copyright 2011 Wolfson Microelectronics plc + * + * Author: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; version 2. + * + * 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 <common.h> +#include <regmap.h> +#include <malloc.h> +#include <linux/log2.h> + +#include "internal.h" + +static LIST_HEAD(regmaps); + +/* + * regmap_init - initialize and register a regmap + * + * @dev: The device the new regmap belongs to + * @bus: The regmap_bus providing read/write access to the map + * @bus_context: Context pointer for the bus ops + * @config: Configuration options for this map + * + * Returns a pointer to the new map or a ERR_PTR value on failure + */ +struct regmap *regmap_init(struct device_d *dev, + const struct regmap_bus *bus, + void *bus_context, + const struct regmap_config *config) +{ + struct regmap *map; + + map = xzalloc(sizeof(*map)); + map->dev = dev; + map->bus = bus; + map->name = config->name; + map->bus_context = bus_context; + map->reg_bits = config->reg_bits; + map->reg_stride = config->reg_stride; + if (!map->reg_stride) + map->reg_stride = 1; + map->pad_bits = config->pad_bits; + map->val_bits = config->val_bits; + map->val_bytes = DIV_ROUND_UP(config->val_bits, 8); + map->max_register = config->max_register; + + list_add_tail(&map->list, ®maps); + + return map; +} + +/* + * regmap_init - initialize and register a regmap + * + * @dev: The device the maps is attached to + * @name: Optional name for the map. If given it must match. + * + * Returns a pointer to the regmap or a ERR_PTR value on failure + */ +struct regmap *dev_get_regmap(struct device_d *dev, const char *name) +{ + struct regmap *map; + + list_for_each_entry(map, ®maps, list) { + if (map->dev != dev) + continue; + if (!name) + return map; + if (!strcmp(map->name, name)) + return map; + } + + return ERR_PTR(-ENOENT); +} + +/* + * of_node_to_regmap - get a regmap from a device node + * + * node: The device node + * + * Returns a pointer to the regmap or a ERR_PTR if the node has no + * regmap attached. + */ +struct regmap *of_node_to_regmap(struct device_node *node) +{ + struct regmap *map; + + list_for_each_entry(map, ®maps, list) { + if (map->dev->device_node == node) + return map; + } + + return ERR_PTR(-ENOENT); +} + +/* + * regmap_write - write a register in a map + * + * @map: The map + * @reg: The register offset of the register + * @val: The value to be written + * + * Returns 0 for success or negative error code on failure + */ +int regmap_write(struct regmap *map, unsigned int reg, unsigned int val) +{ + return map->bus->reg_write(map->bus_context, reg, val); +} + +/* + * regmap_write - read a register from a map + * + * @map: The map + * @reg: The register offset of the register + * @val: pointer to value read + * + * Returns 0 for success or negative error code on failure + */ +int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val) +{ + return map->bus->reg_read(map->bus_context, reg, val); +} + +/** + * regmap_bulk_read(): Read data from the device + * + * @map: Register map to read from + * @reg: First register to be read from + * @val: Pointer to store read value + * @val_len: Size of data to read + * + * A value of zero will be returned on success, a negative errno will + * be returned in error cases. + */ +int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val, + size_t val_len) +{ + size_t val_bytes = map->val_bytes; + size_t val_count = val_len / val_bytes; + unsigned int v; + int ret, i; + + if (val_len % val_bytes) + return -EINVAL; + if (!IS_ALIGNED(reg, map->reg_stride)) + return -EINVAL; + if (val_count == 0) + return -EINVAL; + + for (i = 0; i < val_count; i++) { + u32 *u32 = val; + u16 *u16 = val; + u8 *u8 = val; + + ret = regmap_read(map, reg + (i * map->reg_stride), &v); + if (ret != 0) + goto out; + + switch (map->val_bytes) { + case 4: + u32[i] = v; + break; + case 2: + u16[i] = v; + break; + case 1: + u8[i] = v; + break; + default: + return -EINVAL; + } + } + + out: + return ret; +} + +/** + * regmap_bulk_write(): Write values to one or more registers + * + * @map: Register map to write to + * @reg: Initial register to write to + * @val: Block of data to be written, laid out for direct transmission to the + * device + * @val_len: Length of data pointed to by val. + * + * A value of zero will be returned on success, a negative errno will + * be returned in error cases. + */ +int regmap_bulk_write(struct regmap *map, unsigned int reg, + const void *val, size_t val_len) +{ + size_t val_bytes = map->val_bytes; + size_t val_count = val_len / val_bytes; + int ret, i; + + if (val_len % val_bytes) + return -EINVAL; + if (!IS_ALIGNED(reg, map->reg_stride)) + return -EINVAL; + if (val_count == 0) + return -EINVAL; + + for (i = 0; i < val_count; i++) { + unsigned int ival; + + switch (val_bytes) { + case 1: + ival = *(u8 *)(val + (i * val_bytes)); + break; + case 2: + ival = *(u16 *)(val + (i * val_bytes)); + break; + case 4: + ival = *(u32 *)(val + (i * val_bytes)); + break; + default: + ret = -EINVAL; + goto out; + } + + ret = regmap_write(map, reg + (i * map->reg_stride), + ival); + if (ret != 0) + goto out; + } + + out: + return ret; +} + +int regmap_get_val_bytes(struct regmap *map) +{ + return map->val_bytes; +} + +int regmap_get_max_register(struct regmap *map) +{ + return map->max_register; +} + +int regmap_get_reg_stride(struct regmap *map) +{ + return map->reg_stride; +} + +static int regmap_round_val_bytes(struct regmap *map) +{ + int val_bytes; + + val_bytes = roundup_pow_of_two(map->val_bits) >> 3; + if (!val_bytes) + val_bytes = 1; + + return val_bytes; +} + +static ssize_t regmap_cdev_read(struct cdev *cdev, void *buf, size_t count, loff_t offset, + unsigned long flags) +{ + struct regmap *map = container_of(cdev, struct regmap, cdev); + int val_bytes = regmap_round_val_bytes(map); + int n = count; + int err; + unsigned int ofs = offset; + + if (n < val_bytes || ofs & (val_bytes - 1)) + return -EINVAL; + + ofs /= val_bytes; + ofs *= map->reg_stride; + + while (n > 0) { + err = regmap_read(map, ofs, buf); + if (err) + return (ssize_t)err; + buf += val_bytes; + n -= val_bytes; + ofs += map->reg_stride; + } + + return count; +} + +static ssize_t regmap_cdev_write(struct cdev *cdev, const void *buf, size_t count, loff_t offset, + unsigned long flags) +{ + struct regmap *map = container_of(cdev, struct regmap, cdev); + int val_bytes = regmap_round_val_bytes(map); + int n = count; + int err; + unsigned int ofs = offset; + + if (n < val_bytes || ofs & (val_bytes - 1)) + return -EINVAL; + + ofs /= val_bytes; + ofs *= map->reg_stride; + + while (n > 0) { + u32 val; + + switch (val_bytes) { + case 1: + val = *(u8 *)buf; + break; + case 2: + val = *(u16 *)buf; + break; + case 4: + val = *(u32 *)buf; + break; + default: + return -EINVAL; + }; + + err = regmap_write(map, ofs, val); + if (err) + return (ssize_t)err; + buf += val_bytes; + n -= val_bytes; + ofs += map->reg_stride; + } + + return count; +} + +static struct file_operations regmap_fops = { + .lseek = dev_lseek_default, + .read = regmap_cdev_read, + .write = regmap_cdev_write, +}; + +/* + * regmap_register_cdev - register a devfs file for a regmap + * + * @map: The map + * @name: Optional name of the device file + * + * Returns 0 for success or negative error code on failure + */ +int regmap_register_cdev(struct regmap *map, const char *name) +{ + int ret; + + if (map->cdev.name) + return -EBUSY; + + if (!map->max_register) + return -EINVAL; + + if (name) { + map->cdev.name = xstrdup(name); + } else { + if (map->name) + map->cdev.name = xasprintf("%s-%s", dev_name(map->dev), map->name); + else + map->cdev.name = xstrdup(dev_name(map->dev)); + } + + map->cdev.size = regmap_round_val_bytes(map) * (map->max_register + 1) / + map->reg_stride; + map->cdev.dev = map->dev; + map->cdev.ops = ®map_fops; + + ret = devfs_create(&map->cdev); + if (ret) + return ret; + + return 0; +} + +void regmap_exit(struct regmap *map) +{ + list_del(&map->list); + + if (map->cdev.name) { + devfs_remove(&map->cdev); + free(map->cdev.name); + } + + free(map); +} \ No newline at end of file diff --git a/include/regmap.h b/include/regmap.h new file mode 100644 index 0000000..4cb473c --- /dev/null +++ b/include/regmap.h @@ -0,0 +1,62 @@ +#ifndef __REGMAP_H +#define __REGMAP_H + +/** + * Configuration for the register map of a device. + * + * @name: Optional name of the regmap. Useful when a device has multiple + * register regions. + * + * @reg_bits: Number of bits in a register address, mandatory. + * @reg_stride: The register address stride. Valid register addresses are a + * multiple of this value. If set to 0, a value of 1 will be + * used. + * @pad_bits: Number of bits of padding between register and value. + * @val_bits: Number of bits in a register value, mandatory. + * + * @max_register: Optional, specifies the maximum valid register index. + */ +struct regmap_config { + const char *name; + + int reg_bits; + int reg_stride; + int pad_bits; + int val_bits; + + unsigned int max_register; +}; + +typedef int (*regmap_hw_reg_read)(void *context, unsigned int reg, + unsigned int *val); +typedef int (*regmap_hw_reg_write)(void *context, unsigned int reg, + unsigned int val); + +struct regmap_bus { + regmap_hw_reg_write reg_write; + regmap_hw_reg_read reg_read; +}; + +struct regmap *regmap_init(struct device_d *dev, + const struct regmap_bus *bus, + void *bus_context, + const struct regmap_config *config); + +struct regmap *dev_get_regmap(struct device_d *dev, const char *name); +struct regmap *of_node_to_regmap(struct device_node *node); + +int regmap_register_cdev(struct regmap *map, const char *name); + +int regmap_write(struct regmap *map, unsigned int reg, unsigned int val); +int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val); + +int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val, + size_t val_len); +int regmap_bulk_write(struct regmap *map, unsigned int reg, + const void *val, size_t val_len); + +int regmap_get_val_bytes(struct regmap *map); +int regmap_get_max_register(struct regmap *map); +int regmap_get_reg_stride(struct regmap *map); + +#endif /* __REGMAP_H */ \ No newline at end of file -- 2.7.0.rc3 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox