|  | // 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 | 
|  |  | 
|  | typedef int (*rsmu_rw_device)(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes); | 
|  |  | 
|  | 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_smbus_i2c_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(rsmu->dev); | 
|  |  | 
|  | return i2c_smbus_write_i2c_block_data(client, reg, bytes, buf); | 
|  | } | 
|  |  | 
|  | static int rsmu_smbus_i2c_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(rsmu->dev); | 
|  | int ret; | 
|  |  | 
|  | ret = i2c_smbus_read_i2c_block_data(client, reg, bytes, buf); | 
|  | if (ret == bytes) | 
|  | return 0; | 
|  | else if (ret < 0) | 
|  | return ret; | 
|  | else | 
|  | return -EIO; | 
|  | } | 
|  |  | 
|  | static int rsmu_i2c_read_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 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_i2c_write_device(struct rsmu_ddata *rsmu, u8 reg, u8 *buf, u8 bytes) | 
|  | { | 
|  | struct i2c_client *client = to_i2c_client(rsmu->dev); | 
|  | /* we add 1 byte for device register */ | 
|  | u8 msg[RSMU_MAX_WRITE_COUNT + 1]; | 
|  | 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, | 
|  | rsmu_rw_device rsmu_write_device) | 
|  | { | 
|  | 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_i2c_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, rsmu_i2c_write_device); | 
|  | if (err) | 
|  | return err; | 
|  |  | 
|  | err = rsmu_i2c_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_i2c_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, rsmu_i2c_write_device); | 
|  | if (err) | 
|  | return err; | 
|  |  | 
|  | err = rsmu_i2c_write_device(rsmu, addr, &data, 1); | 
|  | if (err) | 
|  | dev_err(rsmu->dev, | 
|  | "Failed to write offset address 0x%x\n", addr); | 
|  |  | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static int rsmu_smbus_i2c_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, rsmu_smbus_i2c_write_device); | 
|  | if (err) | 
|  | return err; | 
|  |  | 
|  | err = rsmu_smbus_i2c_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_smbus_i2c_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, rsmu_smbus_i2c_write_device); | 
|  | if (err) | 
|  | return err; | 
|  |  | 
|  | err = rsmu_smbus_i2c_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_i2c_cm_regmap_config = { | 
|  | .reg_bits = 32, | 
|  | .val_bits = 8, | 
|  | .max_register = 0x20120000, | 
|  | .reg_read = rsmu_i2c_reg_read, | 
|  | .reg_write = rsmu_i2c_reg_write, | 
|  | .cache_type = REGCACHE_NONE, | 
|  | }; | 
|  |  | 
|  | static const struct regmap_config rsmu_smbus_i2c_cm_regmap_config = { | 
|  | .reg_bits = 32, | 
|  | .val_bits = 8, | 
|  | .max_register = 0x20120000, | 
|  | .reg_read = rsmu_smbus_i2c_reg_read, | 
|  | .reg_write = rsmu_smbus_i2c_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: | 
|  | if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { | 
|  | cfg = &rsmu_i2c_cm_regmap_config; | 
|  | } else if (i2c_check_functionality(client->adapter, | 
|  | I2C_FUNC_SMBUS_I2C_BLOCK)) { | 
|  | cfg = &rsmu_smbus_i2c_cm_regmap_config; | 
|  | } else { | 
|  | dev_err(rsmu->dev, "Unsupported i2c adapter\n"); | 
|  | return -ENOTSUPP; | 
|  | } | 
|  | 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"); |