--- /dev/null
+// 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");
projects / kernel.git / commitdiff