1 files changed, 666 insertions, 0 deletions

diff --git a/drivers/iio/common/ssp_sensors/ssp_dev.c b/drivers/iio/common/ssp_sensors/ssp_dev.c
new file mode 100644
index 000000000..e64d24214
--- /dev/null
+++ b/drivers/iio/common/ssp_sensors/ssp_dev.c
@@ -0,0 +1,666 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mfd/core.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/property.h>
+
+#include "ssp.h"
+
+#define SSP_WDT_TIME			10000
+#define SSP_LIMIT_RESET_CNT		20
+#define SSP_LIMIT_TIMEOUT_CNT		3
+
+/* It is possible that it is max clk rate for version 1.0 of bootcode */
+#define SSP_BOOT_SPI_HZ	400000
+
+/*
+ * These fields can look enigmatic but this structure is used mainly to flat
+ * some values and depends on command type.
+ */
+struct ssp_instruction {
+	__le32 a;
+	__le32 b;
+	u8 c;
+} __attribute__((__packed__));
+
+static const u8 ssp_magnitude_table[] = {110, 85, 171, 71, 203, 195, 0, 67,
+	208, 56, 175, 244, 206, 213, 0, 92, 250, 0, 55, 48, 189, 252, 171,
+	243, 13, 45, 250};
+
+static const struct ssp_sensorhub_info ssp_rinato_info = {
+	.fw_name = "ssp_B2.fw",
+	.fw_crashed_name = "ssp_crashed.fw",
+	.fw_rev = 14052300,
+	.mag_table = ssp_magnitude_table,
+	.mag_length = ARRAY_SIZE(ssp_magnitude_table),
+};
+
+static const struct ssp_sensorhub_info ssp_thermostat_info = {
+	.fw_name = "thermostat_B2.fw",
+	.fw_crashed_name = "ssp_crashed.fw",
+	.fw_rev = 14080600,
+	.mag_table = ssp_magnitude_table,
+	.mag_length = ARRAY_SIZE(ssp_magnitude_table),
+};
+
+static const struct mfd_cell sensorhub_sensor_devs[] = {
+	{
+		.name = "ssp-accelerometer",
+	},
+	{
+		.name = "ssp-gyroscope",
+	},
+};
+
+static void ssp_toggle_mcu_reset_gpio(struct ssp_data *data)
+{
+	gpiod_set_value(data->mcu_reset_gpiod, 0);
+	usleep_range(1000, 1200);
+	gpiod_set_value(data->mcu_reset_gpiod, 1);
+	msleep(50);
+}
+
+static void ssp_sync_available_sensors(struct ssp_data *data)
+{
+	int i, ret;
+
+	for (i = 0; i < SSP_SENSOR_MAX; ++i) {
+		if (data->available_sensors & BIT(i)) {
+			ret = ssp_enable_sensor(data, i, data->delay_buf[i]);
+			if (ret < 0) {
+				dev_err(&data->spi->dev,
+					"Sync sensor nr: %d fail\n", i);
+				continue;
+			}
+		}
+	}
+
+	ret = ssp_command(data, SSP_MSG2SSP_AP_MCU_SET_DUMPMODE,
+			  data->mcu_dump_mode);
+	if (ret < 0)
+		dev_err(&data->spi->dev,
+			"SSP_MSG2SSP_AP_MCU_SET_DUMPMODE failed\n");
+}
+
+static void ssp_enable_mcu(struct ssp_data *data, bool enable)
+{
+	dev_info(&data->spi->dev, "current shutdown = %d, old = %d\n", enable,
+		 data->shut_down);
+
+	if (enable && data->shut_down) {
+		data->shut_down = false;
+		enable_irq(data->spi->irq);
+		enable_irq_wake(data->spi->irq);
+	} else if (!enable && !data->shut_down) {
+		data->shut_down = true;
+		disable_irq(data->spi->irq);
+		disable_irq_wake(data->spi->irq);
+	} else {
+		dev_warn(&data->spi->dev, "current shutdown = %d, old = %d\n",
+			 enable, data->shut_down);
+	}
+}
+
+/*
+ * This function is the first one which communicates with the mcu so it is
+ * possible that the first attempt will fail
+ */
+static int ssp_check_fwbl(struct ssp_data *data)
+{
+	int retries = 0;
+
+	while (retries++ < 5) {
+		data->cur_firm_rev = ssp_get_firmware_rev(data);
+		if (data->cur_firm_rev == SSP_INVALID_REVISION ||
+		    data->cur_firm_rev == SSP_INVALID_REVISION2) {
+			dev_warn(&data->spi->dev,
+				 "Invalid revision, trying %d time\n", retries);
+		} else {
+			break;
+		}
+	}
+
+	if (data->cur_firm_rev == SSP_INVALID_REVISION ||
+	    data->cur_firm_rev == SSP_INVALID_REVISION2) {
+		dev_err(&data->spi->dev, "SSP_INVALID_REVISION\n");
+		return SSP_FW_DL_STATE_NEED_TO_SCHEDULE;
+	}
+
+	dev_info(&data->spi->dev,
+		 "MCU Firm Rev : Old = %8u, New = %8u\n",
+		 data->cur_firm_rev,
+		 data->sensorhub_info->fw_rev);
+
+	if (data->cur_firm_rev != data->sensorhub_info->fw_rev)
+		return SSP_FW_DL_STATE_NEED_TO_SCHEDULE;
+
+	return SSP_FW_DL_STATE_NONE;
+}
+
+static void ssp_reset_mcu(struct ssp_data *data)
+{
+	ssp_enable_mcu(data, false);
+	ssp_clean_pending_list(data);
+	ssp_toggle_mcu_reset_gpio(data);
+	ssp_enable_mcu(data, true);
+}
+
+static void ssp_wdt_work_func(struct work_struct *work)
+{
+	struct ssp_data *data = container_of(work, struct ssp_data, work_wdt);
+
+	dev_err(&data->spi->dev, "%s - Sensor state: 0x%x, RC: %u, CC: %u\n",
+		__func__, data->available_sensors, data->reset_cnt,
+		data->com_fail_cnt);
+
+	ssp_reset_mcu(data);
+	data->com_fail_cnt = 0;
+	data->timeout_cnt = 0;
+}
+
+static void ssp_wdt_timer_func(struct timer_list *t)
+{
+	struct ssp_data *data = from_timer(data, t, wdt_timer);
+
+	switch (data->fw_dl_state) {
+	case SSP_FW_DL_STATE_FAIL:
+	case SSP_FW_DL_STATE_DOWNLOADING:
+	case SSP_FW_DL_STATE_SYNC:
+		goto _mod;
+	}
+
+	if (data->timeout_cnt > SSP_LIMIT_TIMEOUT_CNT ||
+	    data->com_fail_cnt > SSP_LIMIT_RESET_CNT)
+		queue_work(system_power_efficient_wq, &data->work_wdt);
+_mod:
+	mod_timer(&data->wdt_timer, jiffies + msecs_to_jiffies(SSP_WDT_TIME));
+}
+
+static void ssp_enable_wdt_timer(struct ssp_data *data)
+{
+	mod_timer(&data->wdt_timer, jiffies + msecs_to_jiffies(SSP_WDT_TIME));
+}
+
+static void ssp_disable_wdt_timer(struct ssp_data *data)
+{
+	del_timer_sync(&data->wdt_timer);
+	cancel_work_sync(&data->work_wdt);
+}
+
+/**
+ * ssp_get_sensor_delay() - gets sensor data acquisition period
+ * @data:	sensorhub structure
+ * @type:	SSP sensor type
+ *
+ * Returns acquisition period in ms
+ */
+u32 ssp_get_sensor_delay(struct ssp_data *data, enum ssp_sensor_type type)
+{
+	return data->delay_buf[type];
+}
+EXPORT_SYMBOL_NS(ssp_get_sensor_delay, IIO_SSP_SENSORS);
+
+/**
+ * ssp_enable_sensor() - enables data acquisition for sensor
+ * @data:	sensorhub structure
+ * @type:	SSP sensor type
+ * @delay:	delay in ms
+ *
+ * Returns 0 or negative value in case of error
+ */
+int ssp_enable_sensor(struct ssp_data *data, enum ssp_sensor_type type,
+		      u32 delay)
+{
+	int ret;
+	struct ssp_instruction to_send;
+
+	to_send.a = cpu_to_le32(delay);
+	to_send.b = cpu_to_le32(data->batch_latency_buf[type]);
+	to_send.c = data->batch_opt_buf[type];
+
+	switch (data->check_status[type]) {
+	case SSP_INITIALIZATION_STATE:
+		/* do calibration step, now just enable */
+	case SSP_ADD_SENSOR_STATE:
+		ret = ssp_send_instruction(data,
+					   SSP_MSG2SSP_INST_BYPASS_SENSOR_ADD,
+					   type,
+					   (u8 *)&to_send, sizeof(to_send));
+		if (ret < 0) {
+			dev_err(&data->spi->dev, "Enabling sensor failed\n");
+			data->check_status[type] = SSP_NO_SENSOR_STATE;
+			goto derror;
+		}
+
+		data->sensor_enable |= BIT(type);
+		data->check_status[type] = SSP_RUNNING_SENSOR_STATE;
+		break;
+	case SSP_RUNNING_SENSOR_STATE:
+		ret = ssp_send_instruction(data,
+					   SSP_MSG2SSP_INST_CHANGE_DELAY, type,
+					   (u8 *)&to_send, sizeof(to_send));
+		if (ret < 0) {
+			dev_err(&data->spi->dev,
+				"Changing sensor delay failed\n");
+			goto derror;
+		}
+		break;
+	default:
+		data->check_status[type] = SSP_ADD_SENSOR_STATE;
+		break;
+	}
+
+	data->delay_buf[type] = delay;
+
+	if (atomic_inc_return(&data->enable_refcount) == 1)
+		ssp_enable_wdt_timer(data);
+
+	return 0;
+
+derror:
+	return ret;
+}
+EXPORT_SYMBOL_NS(ssp_enable_sensor, IIO_SSP_SENSORS);
+
+/**
+ * ssp_change_delay() - changes data acquisition for sensor
+ * @data:	sensorhub structure
+ * @type:	SSP sensor type
+ * @delay:	delay in ms
+ *
+ * Returns 0 or negative value in case of error
+ */
+int ssp_change_delay(struct ssp_data *data, enum ssp_sensor_type type,
+		     u32 delay)
+{
+	int ret;
+	struct ssp_instruction to_send;
+
+	to_send.a = cpu_to_le32(delay);
+	to_send.b = cpu_to_le32(data->batch_latency_buf[type]);
+	to_send.c = data->batch_opt_buf[type];
+
+	ret = ssp_send_instruction(data, SSP_MSG2SSP_INST_CHANGE_DELAY, type,
+				   (u8 *)&to_send, sizeof(to_send));
+	if (ret < 0) {
+		dev_err(&data->spi->dev, "Changing sensor delay failed\n");
+		return ret;
+	}
+
+	data->delay_buf[type] = delay;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS(ssp_change_delay, IIO_SSP_SENSORS);
+
+/**
+ * ssp_disable_sensor() - disables sensor
+ *
+ * @data:	sensorhub structure
+ * @type:	SSP sensor type
+ *
+ * Returns 0 or negative value in case of error
+ */
+int ssp_disable_sensor(struct ssp_data *data, enum ssp_sensor_type type)
+{
+	int ret;
+	__le32 command;
+
+	if (data->sensor_enable & BIT(type)) {
+		command = cpu_to_le32(data->delay_buf[type]);
+
+		ret = ssp_send_instruction(data,
+					   SSP_MSG2SSP_INST_BYPASS_SENSOR_RM,
+					   type, (u8 *)&command,
+					   sizeof(command));
+		if (ret < 0) {
+			dev_err(&data->spi->dev, "Remove sensor fail\n");
+			return ret;
+		}
+
+		data->sensor_enable &= ~BIT(type);
+	}
+
+	data->check_status[type] = SSP_ADD_SENSOR_STATE;
+
+	if (atomic_dec_and_test(&data->enable_refcount))
+		ssp_disable_wdt_timer(data);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS(ssp_disable_sensor, IIO_SSP_SENSORS);
+
+static irqreturn_t ssp_irq_thread_fn(int irq, void *dev_id)
+{
+	struct ssp_data *data = dev_id;
+
+	/*
+	 * This wrapper is done to preserve error path for ssp_irq_msg, also
+	 * it is defined in different file.
+	 */
+	ssp_irq_msg(data);
+
+	return IRQ_HANDLED;
+}
+
+static int ssp_initialize_mcu(struct ssp_data *data)
+{
+	int ret;
+
+	ssp_clean_pending_list(data);
+
+	ret = ssp_get_chipid(data);
+	if (ret != SSP_DEVICE_ID) {
+		dev_err(&data->spi->dev, "%s - MCU %s ret = %d\n", __func__,
+			ret < 0 ? "is not working" : "identification failed",
+			ret);
+		return ret < 0 ? ret : -ENODEV;
+	}
+
+	dev_info(&data->spi->dev, "MCU device ID = %d\n", ret);
+
+	/*
+	 * needs clarification, for now do not want to export all transfer
+	 * methods to sensors' drivers
+	 */
+	ret = ssp_set_magnetic_matrix(data);
+	if (ret < 0) {
+		dev_err(&data->spi->dev,
+			"%s - ssp_set_magnetic_matrix failed\n", __func__);
+		return ret;
+	}
+
+	data->available_sensors = ssp_get_sensor_scanning_info(data);
+	if (data->available_sensors == 0) {
+		dev_err(&data->spi->dev,
+			"%s - ssp_get_sensor_scanning_info failed\n", __func__);
+		return -EIO;
+	}
+
+	data->cur_firm_rev = ssp_get_firmware_rev(data);
+	dev_info(&data->spi->dev, "MCU Firm Rev : New = %8u\n",
+		 data->cur_firm_rev);
+
+	return ssp_command(data, SSP_MSG2SSP_AP_MCU_DUMP_CHECK, 0);
+}
+
+/*
+ * sensorhub can request its reinitialization as some brutal and rare error
+ * handling. It can be requested from the MCU.
+ */
+static void ssp_refresh_task(struct work_struct *work)
+{
+	struct ssp_data *data = container_of((struct delayed_work *)work,
+					     struct ssp_data, work_refresh);
+
+	dev_info(&data->spi->dev, "refreshing\n");
+
+	data->reset_cnt++;
+
+	if (ssp_initialize_mcu(data) >= 0) {
+		ssp_sync_available_sensors(data);
+		if (data->last_ap_state != 0)
+			ssp_command(data, data->last_ap_state, 0);
+
+		if (data->last_resume_state != 0)
+			ssp_command(data, data->last_resume_state, 0);
+
+		data->timeout_cnt = 0;
+		data->com_fail_cnt = 0;
+	}
+}
+
+int ssp_queue_ssp_refresh_task(struct ssp_data *data, unsigned int delay)
+{
+	cancel_delayed_work_sync(&data->work_refresh);
+
+	return queue_delayed_work(system_power_efficient_wq,
+				  &data->work_refresh,
+				  msecs_to_jiffies(delay));
+}
+
+static const struct of_device_id ssp_of_match[] = {
+	{
+		.compatible	= "samsung,sensorhub-rinato",
+		.data		= &ssp_rinato_info,
+	}, {
+		.compatible	= "samsung,sensorhub-thermostat",
+		.data		= &ssp_thermostat_info,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, ssp_of_match);
+
+static struct ssp_data *ssp_parse_dt(struct device *dev)
+{
+	struct ssp_data *data;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return NULL;
+
+	data->mcu_ap_gpiod = devm_gpiod_get(dev, "mcu-ap", GPIOD_IN);
+	if (IS_ERR(data->mcu_ap_gpiod))
+		return NULL;
+
+	data->ap_mcu_gpiod = devm_gpiod_get(dev, "ap-mcu", GPIOD_OUT_HIGH);
+	if (IS_ERR(data->ap_mcu_gpiod))
+		return NULL;
+
+	data->mcu_reset_gpiod = devm_gpiod_get(dev, "mcu-reset",
+					       GPIOD_OUT_HIGH);
+	if (IS_ERR(data->mcu_reset_gpiod))
+		return NULL;
+
+	data->sensorhub_info = device_get_match_data(dev);
+
+	dev_set_drvdata(dev, data);
+
+	return data;
+}
+
+/**
+ * ssp_register_consumer() - registers iio consumer in ssp framework
+ *
+ * @indio_dev:	consumer iio device
+ * @type:	ssp sensor type
+ */
+void ssp_register_consumer(struct iio_dev *indio_dev, enum ssp_sensor_type type)
+{
+	struct ssp_data *data = dev_get_drvdata(indio_dev->dev.parent->parent);
+
+	data->sensor_devs[type] = indio_dev;
+}
+EXPORT_SYMBOL_NS(ssp_register_consumer, IIO_SSP_SENSORS);
+
+static int ssp_probe(struct spi_device *spi)
+{
+	int ret, i;
+	struct ssp_data *data;
+
+	data = ssp_parse_dt(&spi->dev);
+	if (!data) {
+		dev_err(&spi->dev, "Failed to find platform data\n");
+		return -ENODEV;
+	}
+
+	ret = mfd_add_devices(&spi->dev, PLATFORM_DEVID_NONE,
+			      sensorhub_sensor_devs,
+			      ARRAY_SIZE(sensorhub_sensor_devs), NULL, 0, NULL);
+	if (ret < 0) {
+		dev_err(&spi->dev, "mfd add devices fail\n");
+		return ret;
+	}
+
+	spi->mode = SPI_MODE_1;
+	ret = spi_setup(spi);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Failed to setup spi\n");
+		return ret;
+	}
+
+	data->fw_dl_state = SSP_FW_DL_STATE_NONE;
+	data->spi = spi;
+	spi_set_drvdata(spi, data);
+
+	mutex_init(&data->comm_lock);
+
+	for (i = 0; i < SSP_SENSOR_MAX; ++i) {
+		data->delay_buf[i] = SSP_DEFAULT_POLLING_DELAY;
+		data->batch_latency_buf[i] = 0;
+		data->batch_opt_buf[i] = 0;
+		data->check_status[i] = SSP_INITIALIZATION_STATE;
+	}
+
+	data->delay_buf[SSP_BIO_HRM_LIB] = 100;
+
+	data->time_syncing = true;
+
+	mutex_init(&data->pending_lock);
+	INIT_LIST_HEAD(&data->pending_list);
+
+	atomic_set(&data->enable_refcount, 0);
+
+	INIT_WORK(&data->work_wdt, ssp_wdt_work_func);
+	INIT_DELAYED_WORK(&data->work_refresh, ssp_refresh_task);
+
+	timer_setup(&data->wdt_timer, ssp_wdt_timer_func, 0);
+
+	ret = request_threaded_irq(data->spi->irq, NULL,
+				   ssp_irq_thread_fn,
+				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				   "SSP_Int", data);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Irq request fail\n");
+		goto err_setup_irq;
+	}
+
+	/* Let's start with enabled one so irq balance could be ok */
+	data->shut_down = false;
+
+	/* just to avoid unbalanced irq set wake up */
+	enable_irq_wake(data->spi->irq);
+
+	data->fw_dl_state = ssp_check_fwbl(data);
+	if (data->fw_dl_state == SSP_FW_DL_STATE_NONE) {
+		ret = ssp_initialize_mcu(data);
+		if (ret < 0) {
+			dev_err(&spi->dev, "Initialize_mcu failed\n");
+			goto err_read_reg;
+		}
+	} else {
+		dev_err(&spi->dev, "Firmware version not supported\n");
+		ret = -EPERM;
+		goto err_read_reg;
+	}
+
+	return 0;
+
+err_read_reg:
+	free_irq(data->spi->irq, data);
+err_setup_irq:
+	mutex_destroy(&data->pending_lock);
+	mutex_destroy(&data->comm_lock);
+
+	dev_err(&spi->dev, "Probe failed!\n");
+
+	return ret;
+}
+
+static void ssp_remove(struct spi_device *spi)
+{
+	struct ssp_data *data = spi_get_drvdata(spi);
+
+	if (ssp_command(data, SSP_MSG2SSP_AP_STATUS_SHUTDOWN, 0) < 0)
+		dev_err(&data->spi->dev,
+			"SSP_MSG2SSP_AP_STATUS_SHUTDOWN failed\n");
+
+	ssp_enable_mcu(data, false);
+	ssp_disable_wdt_timer(data);
+
+	ssp_clean_pending_list(data);
+
+	free_irq(data->spi->irq, data);
+
+	del_timer_sync(&data->wdt_timer);
+	cancel_work_sync(&data->work_wdt);
+
+	mutex_destroy(&data->comm_lock);
+	mutex_destroy(&data->pending_lock);
+
+	mfd_remove_devices(&spi->dev);
+}
+
+static int ssp_suspend(struct device *dev)
+{
+	int ret;
+	struct ssp_data *data = spi_get_drvdata(to_spi_device(dev));
+
+	data->last_resume_state = SSP_MSG2SSP_AP_STATUS_SUSPEND;
+
+	if (atomic_read(&data->enable_refcount) > 0)
+		ssp_disable_wdt_timer(data);
+
+	ret = ssp_command(data, SSP_MSG2SSP_AP_STATUS_SUSPEND, 0);
+	if (ret < 0) {
+		dev_err(&data->spi->dev,
+			"%s SSP_MSG2SSP_AP_STATUS_SUSPEND failed\n", __func__);
+
+		ssp_enable_wdt_timer(data);
+		return ret;
+	}
+
+	data->time_syncing = false;
+	disable_irq(data->spi->irq);
+
+	return 0;
+}
+
+static int ssp_resume(struct device *dev)
+{
+	int ret;
+	struct ssp_data *data = spi_get_drvdata(to_spi_device(dev));
+
+	enable_irq(data->spi->irq);
+
+	if (atomic_read(&data->enable_refcount) > 0)
+		ssp_enable_wdt_timer(data);
+
+	ret = ssp_command(data, SSP_MSG2SSP_AP_STATUS_RESUME, 0);
+	if (ret < 0) {
+		dev_err(&data->spi->dev,
+			"%s SSP_MSG2SSP_AP_STATUS_RESUME failed\n", __func__);
+		ssp_disable_wdt_timer(data);
+		return ret;
+	}
+
+	/* timesyncing is set by MCU */
+	data->last_resume_state = SSP_MSG2SSP_AP_STATUS_RESUME;
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(ssp_pm_ops, ssp_suspend, ssp_resume);
+
+static struct spi_driver ssp_driver = {
+	.probe = ssp_probe,
+	.remove = ssp_remove,
+	.driver = {
+		.pm = pm_sleep_ptr(&ssp_pm_ops),
+		.of_match_table = ssp_of_match,
+		.name = "sensorhub"
+	},
+};
+
+module_spi_driver(ssp_driver);
+
+MODULE_DESCRIPTION("ssp sensorhub driver");
+MODULE_AUTHOR("Samsung Electronics");
+MODULE_LICENSE("GPL");