| // 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"); |