diff options
Diffstat (limited to 'drivers/usb/typec/mux/fsa4480.c')
| -rw-r--r-- | drivers/usb/typec/mux/fsa4480.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/usb/typec/mux/fsa4480.c b/drivers/usb/typec/mux/fsa4480.c new file mode 100644 index 000000000000..6184f5367190 --- /dev/null +++ b/drivers/usb/typec/mux/fsa4480.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021-2022 Linaro Ltd. + * Copyright (C) 2018-2020 The Linux Foundation + */ + +#include <linux/bits.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/regmap.h> +#include <linux/usb/typec_dp.h> +#include <linux/usb/typec_mux.h> + +#define FSA4480_SWITCH_ENABLE 0x04 +#define FSA4480_SWITCH_SELECT 0x05 +#define FSA4480_SWITCH_STATUS1 0x07 +#define FSA4480_SLOW_L 0x08 +#define FSA4480_SLOW_R 0x09 +#define FSA4480_SLOW_MIC 0x0a +#define FSA4480_SLOW_SENSE 0x0b +#define FSA4480_SLOW_GND 0x0c +#define FSA4480_DELAY_L_R 0x0d +#define FSA4480_DELAY_L_MIC 0x0e +#define FSA4480_DELAY_L_SENSE 0x0f +#define FSA4480_DELAY_L_AGND 0x10 +#define FSA4480_RESET 0x1e +#define FSA4480_MAX_REGISTER 0x1f + +#define FSA4480_ENABLE_DEVICE BIT(7) +#define FSA4480_ENABLE_SBU GENMASK(6, 5) +#define FSA4480_ENABLE_USB GENMASK(4, 3) + +#define FSA4480_SEL_SBU_REVERSE GENMASK(6, 5) +#define FSA4480_SEL_USB GENMASK(4, 3) + +struct fsa4480 { + struct i2c_client *client; + + /* used to serialize concurrent change requests */ + struct mutex lock; + + struct typec_switch_dev *sw; + struct typec_mux_dev *mux; + + struct regmap *regmap; + + u8 cur_enable; + u8 cur_select; +}; + +static const struct regmap_config fsa4480_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = FSA4480_MAX_REGISTER, + /* Accesses only done under fsa4480->lock */ + .disable_locking = true, +}; + +static int fsa4480_switch_set(struct typec_switch_dev *sw, + enum typec_orientation orientation) +{ + struct fsa4480 *fsa = typec_switch_get_drvdata(sw); + u8 new_sel; + + mutex_lock(&fsa->lock); + new_sel = FSA4480_SEL_USB; + if (orientation == TYPEC_ORIENTATION_REVERSE) + new_sel |= FSA4480_SEL_SBU_REVERSE; + + if (new_sel == fsa->cur_select) + goto out_unlock; + + if (fsa->cur_enable & FSA4480_ENABLE_SBU) { + /* Disable SBU output while re-configuring the switch */ + regmap_write(fsa->regmap, FSA4480_SWITCH_ENABLE, + fsa->cur_enable & ~FSA4480_ENABLE_SBU); + + /* 35us to allow the SBU switch to turn off */ + usleep_range(35, 1000); + } + + regmap_write(fsa->regmap, FSA4480_SWITCH_SELECT, new_sel); + fsa->cur_select = new_sel; + + if (fsa->cur_enable & FSA4480_ENABLE_SBU) { + regmap_write(fsa->regmap, FSA4480_SWITCH_ENABLE, fsa->cur_enable); + + /* 15us to allow the SBU switch to turn on again */ + usleep_range(15, 1000); + } + +out_unlock: + mutex_unlock(&fsa->lock); + + return 0; +} + +static int fsa4480_mux_set(struct typec_mux_dev *mux, struct typec_mux_state *state) +{ + struct fsa4480 *fsa = typec_mux_get_drvdata(mux); + u8 new_enable; + + mutex_lock(&fsa->lock); + + new_enable = FSA4480_ENABLE_DEVICE | FSA4480_ENABLE_USB; + if (state->mode >= TYPEC_DP_STATE_A) + new_enable |= FSA4480_ENABLE_SBU; + + if (new_enable == fsa->cur_enable) + goto out_unlock; + + regmap_write(fsa->regmap, FSA4480_SWITCH_ENABLE, new_enable); + fsa->cur_enable = new_enable; + + if (new_enable & FSA4480_ENABLE_SBU) { + /* 15us to allow the SBU switch to turn off */ + usleep_range(15, 1000); + } + +out_unlock: + mutex_unlock(&fsa->lock); + + return 0; +} + +static int fsa4480_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct typec_switch_desc sw_desc = { }; + struct typec_mux_desc mux_desc = { }; + struct fsa4480 *fsa; + + fsa = devm_kzalloc(dev, sizeof(*fsa), GFP_KERNEL); + if (!fsa) + return -ENOMEM; + + fsa->client = client; + mutex_init(&fsa->lock); + + fsa->regmap = devm_regmap_init_i2c(client, &fsa4480_regmap_config); + if (IS_ERR(fsa->regmap)) + return dev_err_probe(dev, PTR_ERR(fsa->regmap), "failed to initialize regmap\n"); + + fsa->cur_enable = FSA4480_ENABLE_DEVICE | FSA4480_ENABLE_USB; + fsa->cur_select = FSA4480_SEL_USB; + + /* set default settings */ + regmap_write(fsa->regmap, FSA4480_SLOW_L, 0x00); + regmap_write(fsa->regmap, FSA4480_SLOW_R, 0x00); + regmap_write(fsa->regmap, FSA4480_SLOW_MIC, 0x00); + regmap_write(fsa->regmap, FSA4480_SLOW_SENSE, 0x00); + regmap_write(fsa->regmap, FSA4480_SLOW_GND, 0x00); + regmap_write(fsa->regmap, FSA4480_DELAY_L_R, 0x00); + regmap_write(fsa->regmap, FSA4480_DELAY_L_MIC, 0x00); + regmap_write(fsa->regmap, FSA4480_DELAY_L_SENSE, 0x00); + regmap_write(fsa->regmap, FSA4480_DELAY_L_AGND, 0x09); + regmap_write(fsa->regmap, FSA4480_SWITCH_SELECT, fsa->cur_select); + regmap_write(fsa->regmap, FSA4480_SWITCH_ENABLE, fsa->cur_enable); + + sw_desc.drvdata = fsa; + sw_desc.fwnode = dev_fwnode(dev); + sw_desc.set = fsa4480_switch_set; + + fsa->sw = typec_switch_register(dev, &sw_desc); + if (IS_ERR(fsa->sw)) + return dev_err_probe(dev, PTR_ERR(fsa->sw), "failed to register typec switch\n"); + + mux_desc.drvdata = fsa; + mux_desc.fwnode = dev_fwnode(dev); + mux_desc.set = fsa4480_mux_set; + + fsa->mux = typec_mux_register(dev, &mux_desc); + if (IS_ERR(fsa->mux)) { + typec_switch_unregister(fsa->sw); + return dev_err_probe(dev, PTR_ERR(fsa->mux), "failed to register typec mux\n"); + } + + i2c_set_clientdata(client, fsa); + return 0; +} + +static int fsa4480_remove(struct i2c_client *client) +{ + struct fsa4480 *fsa = i2c_get_clientdata(client); + + typec_mux_unregister(fsa->mux); + typec_switch_unregister(fsa->sw); + + return 0; +} + +static const struct i2c_device_id fsa4480_table[] = { + { "fsa4480" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, fsa4480_table); + +static const struct of_device_id fsa4480_of_table[] = { + { .compatible = "fcs,fsa4480" }, + { } +}; +MODULE_DEVICE_TABLE(of, fsa4480_of_table); + +static struct i2c_driver fsa4480_driver = { + .driver = { + .name = "fsa4480", + .of_match_table = fsa4480_of_table, + }, + .probe_new = fsa4480_probe, + .remove = fsa4480_remove, + .id_table = fsa4480_table, +}; +module_i2c_driver(fsa4480_driver); + +MODULE_DESCRIPTION("ON Semiconductor FSA4480 driver"); +MODULE_LICENSE("GPL v2"); |