drivers/mfd/rsmu_i2c.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * I2C driver for Renesas Synchronization Management Unit (SMU) devices.
  *
  * Copyright (C) 2021 Integrated Device Technology, Inc., a Renesas Company.
  */

 #include <linux/i2c.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/rsmu.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>

 #include "rsmu.h"

 /*
  * 32-bit register address: the lower 8 bits of the register address come
  * from the offset addr byte and the upper 24 bits come from the page register.
  */
 #define	RSMU_CM_PAGE_ADDR		0xFC
 #define RSMU_CM_PAGE_MASK		0xFFFFFF00
 #define RSMU_CM_ADDRESS_MASK		0x000000FF

 /*
  * 15-bit register address: the lower 7 bits of the register address come
  * from the offset addr byte and the upper 8 bits come from the page register.
  */
 #define	RSMU_SABRE_PAGE_ADDR		0x7F
 #define	RSMU_SABRE_PAGE_WINDOW		128

 static const struct regmap_range_cfg rsmu_sabre_range_cfg[] = {
 	{
 		.range_min = 0,
 		.range_max = 0x400,
 		.selector_reg = RSMU_SABRE_PAGE_ADDR,
 		.selector_mask = 0xFF,
 		.selector_shift = 0,
 		.window_start = 0,
 		.window_len = RSMU_SABRE_PAGE_WINDOW,
 	}
 };

 static bool rsmu_sabre_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case RSMU_SABRE_PAGE_ADDR:
 		return false;
 	default:
 		return true;
 	}
 }

 static int rsmu_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes)
 {
 	struct i2c_client *client = to_i2c_client(rsmu->dev);
 	struct i2c_msg msg[2];
 	int cnt;

 	msg[0].addr = client->addr;
 	msg[0].flags = 0;
 	msg[0].len = 1;
 	msg[0].buf = &reg;

 	msg[1].addr = client->addr;
 	msg[1].flags = I2C_M_RD;
 	msg[1].len = bytes;
 	msg[1].buf = buf;

 	cnt = i2c_transfer(client->adapter, msg, 2);

 	if (cnt < 0) {
 		dev_err(rsmu->dev, "i2c_transfer failed at addr: %04x!", reg);
 		return cnt;
 	} else if (cnt != 2) {
 		dev_err(rsmu->dev,
 			"i2c_transfer sent only %d of 2 messages", cnt);
 		return -EIO;
 	}

 	return 0;
 }

 static int rsmu_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u16 bytes)
 {
 	struct i2c_client *client = to_i2c_client(rsmu->dev);
 	u8 msg[RSMU_MAX_WRITE_COUNT + 1]; /* 1 Byte added for the device register */
 	int cnt;

 	if (bytes > RSMU_MAX_WRITE_COUNT)
 		return -EINVAL;

 	msg[0] = reg;
 	memcpy(&msg[1], buf, bytes);

 	cnt = i2c_master_send(client, msg, bytes + 1);

 	if (cnt < 0) {
 		dev_err(&client->dev,
 			"i2c_master_send failed at addr: %04x!", reg);
 		return cnt;
 	}

 	return 0;
 }

 static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg)
 {
 	u32 page = reg & RSMU_CM_PAGE_MASK;
 	u8 buf[4];
 	int err;

 	/* Do not modify offset register for none-scsr registers */
 	if (reg < RSMU_CM_SCSR_BASE)
 		return 0;

 	/* Simply return if we are on the same page */
 	if (rsmu->page == page)
 		return 0;

 	buf[0] = 0x0;
 	buf[1] = (u8)((page >> 8) & 0xFF);
 	buf[2] = (u8)((page >> 16) & 0xFF);
 	buf[3] = (u8)((page >> 24) & 0xFF);

 	err = rsmu_write_device(rsmu, RSMU_CM_PAGE_ADDR, buf, sizeof(buf));
 	if (err)
 		dev_err(rsmu->dev, "Failed to set page offset 0x%x\n", page);
 	else
 		/* Remember the last page */
 		rsmu->page = page;

 	return err;
 }

 static int rsmu_reg_read(void *context, unsigned int reg, unsigned int *val)
 {
 	struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
 	u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
 	int err;

 	err = rsmu_write_page_register(rsmu, reg);
 	if (err)
 		return err;

 	err = rsmu_read_device(rsmu, addr, (u8 *)val, 1);
 	if (err)
 		dev_err(rsmu->dev, "Failed to read offset address 0x%x\n", addr);

 	return err;
 }

 static int rsmu_reg_write(void *context, unsigned int reg, unsigned int val)
 {
 	struct rsmu_ddata *rsmu = i2c_get_clientdata((struct i2c_client *)context);
 	u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
 	u8 data = (u8)val;
 	int err;

 	err = rsmu_write_page_register(rsmu, reg);
 	if (err)
 		return err;

 	err = rsmu_write_device(rsmu, addr, &data, 1);
 	if (err)
 		dev_err(rsmu->dev,
 			"Failed to write offset address 0x%x\n", addr);

 	return err;
 }

 static const struct regmap_config rsmu_cm_regmap_config = {
 	.reg_bits = 32,
 	.val_bits = 8,
 	.max_register = 0x20120000,
 	.reg_read = rsmu_reg_read,
 	.reg_write = rsmu_reg_write,
 	.cache_type = REGCACHE_NONE,
 };

 static const struct regmap_config rsmu_sabre_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = 0x400,
 	.ranges = rsmu_sabre_range_cfg,
 	.num_ranges = ARRAY_SIZE(rsmu_sabre_range_cfg),
 	.volatile_reg = rsmu_sabre_volatile_reg,
 	.cache_type = REGCACHE_MAPLE,
 	.can_multi_write = true,
 };

 static const struct regmap_config rsmu_sl_regmap_config = {
 	.reg_bits = 16,
 	.val_bits = 8,
 	.reg_format_endian = REGMAP_ENDIAN_BIG,
 	.max_register = 0x340,
 	.cache_type = REGCACHE_NONE,
 	.can_multi_write = true,
 };

 static int rsmu_i2c_probe(struct i2c_client *client)
 {
 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
 	const struct regmap_config *cfg;
 	struct rsmu_ddata *rsmu;
 	int ret;

 	rsmu = devm_kzalloc(&client->dev, sizeof(*rsmu), GFP_KERNEL);
 	if (!rsmu)
 		return -ENOMEM;

 	i2c_set_clientdata(client, rsmu);

 	rsmu->dev = &client->dev;
 	rsmu->type = (enum rsmu_type)id->driver_data;

 	switch (rsmu->type) {
 	case RSMU_CM:
 		cfg = &rsmu_cm_regmap_config;
 		break;
 	case RSMU_SABRE:
 		cfg = &rsmu_sabre_regmap_config;
 		break;
 	case RSMU_SL:
 		cfg = &rsmu_sl_regmap_config;
 		break;
 	default:
 		dev_err(rsmu->dev, "Unsupported RSMU device type: %d\n", rsmu->type);
 		return -ENODEV;
 	}

 	if (rsmu->type == RSMU_CM)
 		rsmu->regmap = devm_regmap_init(&client->dev, NULL, client, cfg);
 	else
 		rsmu->regmap = devm_regmap_init_i2c(client, cfg);
 	if (IS_ERR(rsmu->regmap)) {
 		ret = PTR_ERR(rsmu->regmap);
 		dev_err(rsmu->dev, "Failed to allocate register map: %d\n", ret);
 		return ret;
 	}

 	return rsmu_core_init(rsmu);
 }

 static void rsmu_i2c_remove(struct i2c_client *client)
 {
 	struct rsmu_ddata *rsmu = i2c_get_clientdata(client);

 	rsmu_core_exit(rsmu);
 }

 static const struct i2c_device_id rsmu_i2c_id[] = {
 	{ "8a34000",  RSMU_CM },
 	{ "8a34001",  RSMU_CM },
 	{ "82p33810", RSMU_SABRE },
 	{ "82p33811", RSMU_SABRE },
 	{ "8v19n850", RSMU_SL },
 	{ "8v19n851", RSMU_SL },
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, rsmu_i2c_id);

 static const struct of_device_id rsmu_i2c_of_match[] = {
 	{ .compatible = "idt,8a34000",  .data = (void *)RSMU_CM },
 	{ .compatible = "idt,8a34001",  .data = (void *)RSMU_CM },
 	{ .compatible = "idt,82p33810", .data = (void *)RSMU_SABRE },
 	{ .compatible = "idt,82p33811", .data = (void *)RSMU_SABRE },
 	{ .compatible = "idt,8v19n850", .data = (void *)RSMU_SL },
 	{ .compatible = "idt,8v19n851", .data = (void *)RSMU_SL },
 	{}
 };
 MODULE_DEVICE_TABLE(of, rsmu_i2c_of_match);

 static struct i2c_driver rsmu_i2c_driver = {
 	.driver = {
 		.name = "rsmu-i2c",
 		.of_match_table = rsmu_i2c_of_match,
 	},
 	.probe = rsmu_i2c_probe,
 	.remove	= rsmu_i2c_remove,
 	.id_table = rsmu_i2c_id,
 };

 static int __init rsmu_i2c_init(void)
 {
 	return i2c_add_driver(&rsmu_i2c_driver);
 }
 subsys_initcall(rsmu_i2c_init);

 static void __exit rsmu_i2c_exit(void)
 {
 	i2c_del_driver(&rsmu_i2c_driver);
 }
 module_exit(rsmu_i2c_exit);

 MODULE_DESCRIPTION("Renesas SMU I2C driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* I2C driver for Renesas Synchronization Management Unit (SMU) devices.
	*
	* Copyright (C) 2021 Integrated Device Technology, Inc., a Renesas Company.
	*/

	#include <linux/i2c.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/mfd/core.h>
	#include <linux/mfd/rsmu.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/regmap.h>
	#include <linux/slab.h>

	#include "rsmu.h"

	/*
	* 32-bit register address: the lower 8 bits of the register address come
	* from the offset addr byte and the upper 24 bits come from the page register.
	*/
	#define RSMU_CM_PAGE_ADDR 0xFC
	#define RSMU_CM_PAGE_MASK 0xFFFFFF00
	#define RSMU_CM_ADDRESS_MASK 0x000000FF

	/*
	* 15-bit register address: the lower 7 bits of the register address come
	* from the offset addr byte and the upper 8 bits come from the page register.
	*/
	#define RSMU_SABRE_PAGE_ADDR 0x7F
	#define RSMU_SABRE_PAGE_WINDOW 128

	static const struct regmap_range_cfg rsmu_sabre_range_cfg[] = {
	{
	.range_min = 0,
	.range_max = 0x400,
	.selector_reg = RSMU_SABRE_PAGE_ADDR,
	.selector_mask = 0xFF,
	.selector_shift = 0,
	.window_start = 0,
	.window_len = RSMU_SABRE_PAGE_WINDOW,
	}
	};

	static bool rsmu_sabre_volatile_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case RSMU_SABRE_PAGE_ADDR:
	return false;
	default:
	return true;
	}
	}

	static int rsmu_read_device(struct rsmu_ddata rsmu, u8 reg, u8 buf, u16 bytes)
	{
	struct i2c_client *client = to_i2c_client(rsmu->dev);
	struct i2c_msg msg[2];
	int cnt;

	msg[0].addr = client->addr;
	msg[0].flags = 0;
	msg[0].len = 1;
	msg[0].buf = ®

	msg[1].addr = client->addr;
	msg[1].flags = I2C_M_RD;
	msg[1].len = bytes;
	msg[1].buf = buf;

	cnt = i2c_transfer(client->adapter, msg, 2);

	if (cnt < 0) {
	dev_err(rsmu->dev, "i2c_transfer failed at addr: %04x!", reg);
	return cnt;
	} else if (cnt != 2) {
	dev_err(rsmu->dev,
	"i2c_transfer sent only %d of 2 messages", cnt);
	return -EIO;
	}

	return 0;
	}

	static int rsmu_write_device(struct rsmu_ddata rsmu, u8 reg, u8 buf, u16 bytes)
	{
	struct i2c_client *client = to_i2c_client(rsmu->dev);
	u8 msg[RSMU_MAX_WRITE_COUNT + 1]; /* 1 Byte added for the device register */
	int cnt;

	if (bytes > RSMU_MAX_WRITE_COUNT)
	return -EINVAL;

	msg[0] = reg;
	memcpy(&msg[1], buf, bytes);

	cnt = i2c_master_send(client, msg, bytes + 1);

	if (cnt < 0) {
	dev_err(&client->dev,
	"i2c_master_send failed at addr: %04x!", reg);
	return cnt;
	}

	return 0;
	}

	static int rsmu_write_page_register(struct rsmu_ddata *rsmu, u32 reg)
	{
	u32 page = reg & RSMU_CM_PAGE_MASK;
	u8 buf[4];
	int err;

	/* Do not modify offset register for none-scsr registers */
	if (reg < RSMU_CM_SCSR_BASE)
	return 0;

	/* Simply return if we are on the same page */
	if (rsmu->page == page)
	return 0;

	buf[0] = 0x0;
	buf[1] = (u8)((page >> 8) & 0xFF);
	buf[2] = (u8)((page >> 16) & 0xFF);
	buf[3] = (u8)((page >> 24) & 0xFF);

	err = rsmu_write_device(rsmu, RSMU_CM_PAGE_ADDR, buf, sizeof(buf));
	if (err)
	dev_err(rsmu->dev, "Failed to set page offset 0x%x\n", page);
	else
	/* Remember the last page */
	rsmu->page = page;

	return err;
	}

	static int rsmu_reg_read(void context, unsigned int reg, unsigned int val)
	{
	struct rsmu_ddata rsmu = i2c_get_clientdata((struct i2c_client )context);
	u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
	int err;

	err = rsmu_write_page_register(rsmu, reg);
	if (err)
	return err;

	err = rsmu_read_device(rsmu, addr, (u8 *)val, 1);
	if (err)
	dev_err(rsmu->dev, "Failed to read offset address 0x%x\n", addr);

	return err;
	}

	static int rsmu_reg_write(void *context, unsigned int reg, unsigned int val)
	{
	struct rsmu_ddata rsmu = i2c_get_clientdata((struct i2c_client )context);
	u8 addr = (u8)(reg & RSMU_CM_ADDRESS_MASK);
	u8 data = (u8)val;
	int err;

	err = rsmu_write_page_register(rsmu, reg);
	if (err)
	return err;

	err = rsmu_write_device(rsmu, addr, &data, 1);
	if (err)
	dev_err(rsmu->dev,
	"Failed to write offset address 0x%x\n", addr);

	return err;
	}

	static const struct regmap_config rsmu_cm_regmap_config = {
	.reg_bits = 32,
	.val_bits = 8,
	.max_register = 0x20120000,
	.reg_read = rsmu_reg_read,
	.reg_write = rsmu_reg_write,
	.cache_type = REGCACHE_NONE,
	};

	static const struct regmap_config rsmu_sabre_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0x400,
	.ranges = rsmu_sabre_range_cfg,
	.num_ranges = ARRAY_SIZE(rsmu_sabre_range_cfg),
	.volatile_reg = rsmu_sabre_volatile_reg,
	.cache_type = REGCACHE_MAPLE,
	.can_multi_write = true,
	};

	static const struct regmap_config rsmu_sl_regmap_config = {
	.reg_bits = 16,
	.val_bits = 8,
	.reg_format_endian = REGMAP_ENDIAN_BIG,
	.max_register = 0x340,
	.cache_type = REGCACHE_NONE,
	.can_multi_write = true,
	};

	static int rsmu_i2c_probe(struct i2c_client *client)
	{
	const struct i2c_device_id *id = i2c_client_get_device_id(client);
	const struct regmap_config *cfg;
	struct rsmu_ddata *rsmu;
	int ret;

	rsmu = devm_kzalloc(&client->dev, sizeof(*rsmu), GFP_KERNEL);
	if (!rsmu)
	return -ENOMEM;

	i2c_set_clientdata(client, rsmu);

	rsmu->dev = &client->dev;
	rsmu->type = (enum rsmu_type)id->driver_data;

	switch (rsmu->type) {
	case RSMU_CM:
	cfg = &rsmu_cm_regmap_config;
	break;
	case RSMU_SABRE:
	cfg = &rsmu_sabre_regmap_config;
	break;
	case RSMU_SL:
	cfg = &rsmu_sl_regmap_config;
	break;
	default:
	dev_err(rsmu->dev, "Unsupported RSMU device type: %d\n", rsmu->type);
	return -ENODEV;
	}

	if (rsmu->type == RSMU_CM)
	rsmu->regmap = devm_regmap_init(&client->dev, NULL, client, cfg);
	else
	rsmu->regmap = devm_regmap_init_i2c(client, cfg);
	if (IS_ERR(rsmu->regmap)) {
	ret = PTR_ERR(rsmu->regmap);
	dev_err(rsmu->dev, "Failed to allocate register map: %d\n", ret);
	return ret;
	}

	return rsmu_core_init(rsmu);
	}

	static void rsmu_i2c_remove(struct i2c_client *client)
	{
	struct rsmu_ddata *rsmu = i2c_get_clientdata(client);

	rsmu_core_exit(rsmu);
	}

	static const struct i2c_device_id rsmu_i2c_id[] = {
	{ "8a34000", RSMU_CM },
	{ "8a34001", RSMU_CM },
	{ "82p33810", RSMU_SABRE },
	{ "82p33811", RSMU_SABRE },
	{ "8v19n850", RSMU_SL },
	{ "8v19n851", RSMU_SL },
	{}
	};
	MODULE_DEVICE_TABLE(i2c, rsmu_i2c_id);

	static const struct of_device_id rsmu_i2c_of_match[] = {
	{ .compatible = "idt,8a34000", .data = (void *)RSMU_CM },
	{ .compatible = "idt,8a34001", .data = (void *)RSMU_CM },
	{ .compatible = "idt,82p33810", .data = (void *)RSMU_SABRE },
	{ .compatible = "idt,82p33811", .data = (void *)RSMU_SABRE },
	{ .compatible = "idt,8v19n850", .data = (void *)RSMU_SL },
	{ .compatible = "idt,8v19n851", .data = (void *)RSMU_SL },
	{}
	};
	MODULE_DEVICE_TABLE(of, rsmu_i2c_of_match);

	static struct i2c_driver rsmu_i2c_driver = {
	.driver = {
	.name = "rsmu-i2c",
	.of_match_table = rsmu_i2c_of_match,
	},
	.probe = rsmu_i2c_probe,
	.remove = rsmu_i2c_remove,
	.id_table = rsmu_i2c_id,
	};

	static int __init rsmu_i2c_init(void)
	{
	return i2c_add_driver(&rsmu_i2c_driver);
	}
	subsys_initcall(rsmu_i2c_init);

	static void __exit rsmu_i2c_exit(void)
	{
	i2c_del_driver(&rsmu_i2c_driver);
	}
	module_exit(rsmu_i2c_exit);

	MODULE_DESCRIPTION("Renesas SMU I2C driver");
	MODULE_LICENSE("GPL");