Unverified Commit 65dd2f67 authored by Mark Brown's avatar Mark Brown
Browse files

regmap: Provide a ram backed regmap with raw support 



Provide a simple, 16 bit only, RAM backed regmap which supports raw I/O for
use in testing.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230610-regcache-raw-kunit-v1-1-583112cd28ac@kernel.org


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 9561de3a

drivers/base/regmap/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ obj-$(CONFIG_DEBUG_FS) += regmap-debugfs.o 
obj-$(CONFIG_REGMAP_KUNIT) += regmap-kunit.o

obj-$(CONFIG_REGMAP_AC97) += regmap-ac97.o

obj-$(CONFIG_REGMAP_I2C) += regmap-i2c.o

obj-$(CONFIG_REGMAP_RAM) += regmap-ram.o

obj-$(CONFIG_REGMAP_RAM) += regmap-ram.o regmap-raw-ram.o

obj-$(CONFIG_REGMAP_SLIMBUS) += regmap-slimbus.o

obj-$(CONFIG_REGMAP_SPI) += regmap-spi.o

obj-$(CONFIG_REGMAP_SPMI) += regmap-spmi.o

drivers/base/regmap/internal.h

+8 −0
Original line number Diff line number Diff line
@@ -312,6 +312,7 @@ struct regmap_ram_data { 
	unsigned int *vals;  /* Allocatd by caller */

	bool *read;

	bool *written;

	enum regmap_endian reg_endian;

};



/*
@@ -326,5 +327,12 @@ struct regmap *__regmap_init_ram(const struct regmap_config *config, 
#define regmap_init_ram(config, data)					\

	__regmap_lockdep_wrapper(__regmap_init_ram, #config, config, data)



struct regmap *__regmap_init_raw_ram(const struct regmap_config *config,

				     struct regmap_ram_data *data,

				     struct lock_class_key *lock_key,

				     const char *lock_name);



#define regmap_init_raw_ram(config, data)				\

	__regmap_lockdep_wrapper(__regmap_init_raw_ram, #config, config, data)



#endif

drivers/base/regmap/regmap-raw-ram.c

0 → 100644
+133 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

//

// Register map access API - Memory region with raw access

//

// This is intended for testing only

//

// Copyright (c) 2023, Arm Ltd



#include <linux/clk.h>

#include <linux/err.h>

#include <linux/io.h>

#include <linux/module.h>

#include <linux/regmap.h>

#include <linux/slab.h>

#include <linux/swab.h>



#include "internal.h"



static unsigned int decode_reg(enum regmap_endian endian, const void *reg)

{

	const u16 *r = reg;



	if (endian == REGMAP_ENDIAN_BIG)

		return be16_to_cpu(*r);

	else

		return le16_to_cpu(*r);

}



static int regmap_raw_ram_gather_write(void *context,

				       const void *reg, size_t reg_len,

				       const void *val, size_t val_len)

{

	struct regmap_ram_data *data = context;

	unsigned int r;

	u16 *our_buf = (u16 *)data->vals;

	int i;



	if (reg_len != 2)

		return -EINVAL;

	if (val_len % 2)

		return -EINVAL;



	r = decode_reg(data->reg_endian, reg);

	memcpy(&our_buf[r], val, val_len);



	for (i = 0; i < val_len / 2; i++)

		data->written[r + i] = true;

	

	return 0;

}



static int regmap_raw_ram_write(void *context, const void *data, size_t count)

{

	return regmap_raw_ram_gather_write(context, data, 2,

					   data + 2, count - 2);

}



static int regmap_raw_ram_read(void *context,

			       const void *reg, size_t reg_len,

			       void *val, size_t val_len)

{

	struct regmap_ram_data *data = context;

	unsigned int r;

	u16 *our_buf = (u16 *)data->vals;

	int i;



	if (reg_len != 2)

		return -EINVAL;

	if (val_len % 2)

		return -EINVAL;



	r = decode_reg(data->reg_endian, reg);

	memcpy(val, &our_buf[r], val_len);



	for (i = 0; i < val_len / 2; i++)

		data->read[r + i] = true;



	return 0;

}



static void regmap_raw_ram_free_context(void *context)

{

	struct regmap_ram_data *data = context;



	kfree(data->vals);

	kfree(data->read);

	kfree(data->written);

	kfree(data);

}



static const struct regmap_bus regmap_raw_ram = {

	.fast_io = true,

	.write = regmap_raw_ram_write,

	.gather_write = regmap_raw_ram_gather_write,

	.read = regmap_raw_ram_read,

	.free_context = regmap_raw_ram_free_context,

};



struct regmap *__regmap_init_raw_ram(const struct regmap_config *config,

				     struct regmap_ram_data *data,

				     struct lock_class_key *lock_key,

				     const char *lock_name)

{

	struct regmap *map;



	if (config->reg_bits != 16)

		return ERR_PTR(-EINVAL);



	if (!config->max_register) {

		pr_crit("No max_register specified for RAM regmap\n");

		return ERR_PTR(-EINVAL);

	}



	data->read = kcalloc(sizeof(bool), config->max_register + 1,

			     GFP_KERNEL);

	if (!data->read)

		return ERR_PTR(-ENOMEM);



	data->written = kcalloc(sizeof(bool), config->max_register + 1,

				GFP_KERNEL);

	if (!data->written)

		return ERR_PTR(-ENOMEM);



	data->reg_endian = config->reg_format_endian;



	map = __regmap_init(NULL, &regmap_raw_ram, data, config,

			    lock_key, lock_name);



	return map;

}

EXPORT_SYMBOL_GPL(__regmap_init_raw_ram);



MODULE_LICENSE("GPL v2");