1 files changed, 608 insertions, 0 deletions

diff --git a/drivers/iio/common/ssp_sensors/ssp_spi.c b/drivers/iio/common/ssp_sensors/ssp_spi.c
new file mode 100644
index 000000000000..704284a475ae
--- /dev/null
+++ b/drivers/iio/common/ssp_sensors/ssp_spi.c
@@ -0,0 +1,608 @@
+/*
+ *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ */
+
+#include "ssp.h"
+
+#define SSP_DEV (&data->spi->dev)
+#define SSP_GET_MESSAGE_TYPE(data) (data & (3 << SSP_RW))
+
+/*
+ * SSP -> AP Instruction
+ * They tell what packet type can be expected. In the future there will
+ * be less of them. BYPASS means common sensor packets with accel, gyro,
+ * hrm etc. data. LIBRARY and META are mock-up's for now.
+ */
+#define SSP_MSG2AP_INST_BYPASS_DATA		0x37
+#define SSP_MSG2AP_INST_LIBRARY_DATA		0x01
+#define SSP_MSG2AP_INST_DEBUG_DATA		0x03
+#define SSP_MSG2AP_INST_BIG_DATA		0x04
+#define SSP_MSG2AP_INST_META_DATA		0x05
+#define SSP_MSG2AP_INST_TIME_SYNC		0x06
+#define SSP_MSG2AP_INST_RESET			0x07
+
+#define SSP_UNIMPLEMENTED -1
+
+struct ssp_msg_header {
+	u8 cmd;
+	__le16 length;
+	__le16 options;
+	__le32 data;
+} __attribute__((__packed__));
+
+struct ssp_msg {
+	u16 length;
+	u16 options;
+	struct list_head list;
+	struct completion *done;
+	struct ssp_msg_header *h;
+	char *buffer;
+};
+
+static const int ssp_offset_map[SSP_SENSOR_MAX] = {
+	[SSP_ACCELEROMETER_SENSOR] =		SSP_ACCELEROMETER_SIZE +
+						SSP_TIME_SIZE,
+	[SSP_GYROSCOPE_SENSOR] =		SSP_GYROSCOPE_SIZE +
+						SSP_TIME_SIZE,
+	[SSP_GEOMAGNETIC_UNCALIB_SENSOR] =	SSP_UNIMPLEMENTED,
+	[SSP_GEOMAGNETIC_RAW] =			SSP_UNIMPLEMENTED,
+	[SSP_GEOMAGNETIC_SENSOR] =		SSP_UNIMPLEMENTED,
+	[SSP_PRESSURE_SENSOR] =			SSP_UNIMPLEMENTED,
+	[SSP_GESTURE_SENSOR] =			SSP_UNIMPLEMENTED,
+	[SSP_PROXIMITY_SENSOR] =		SSP_UNIMPLEMENTED,
+	[SSP_TEMPERATURE_HUMIDITY_SENSOR] =	SSP_UNIMPLEMENTED,
+	[SSP_LIGHT_SENSOR] =			SSP_UNIMPLEMENTED,
+	[SSP_PROXIMITY_RAW] =			SSP_UNIMPLEMENTED,
+	[SSP_ORIENTATION_SENSOR] =		SSP_UNIMPLEMENTED,
+	[SSP_STEP_DETECTOR] =			SSP_UNIMPLEMENTED,
+	[SSP_SIG_MOTION_SENSOR] =		SSP_UNIMPLEMENTED,
+	[SSP_GYRO_UNCALIB_SENSOR] =		SSP_UNIMPLEMENTED,
+	[SSP_GAME_ROTATION_VECTOR] =		SSP_UNIMPLEMENTED,
+	[SSP_ROTATION_VECTOR] =			SSP_UNIMPLEMENTED,
+	[SSP_STEP_COUNTER] =			SSP_UNIMPLEMENTED,
+	[SSP_BIO_HRM_RAW] =			SSP_BIO_HRM_RAW_SIZE +
+						SSP_TIME_SIZE,
+	[SSP_BIO_HRM_RAW_FAC] =			SSP_BIO_HRM_RAW_FAC_SIZE +
+						SSP_TIME_SIZE,
+	[SSP_BIO_HRM_LIB] =			SSP_BIO_HRM_LIB_SIZE +
+						SSP_TIME_SIZE,
+};
+
+#define SSP_HEADER_SIZE		(sizeof(struct ssp_msg_header))
+#define SSP_HEADER_SIZE_ALIGNED	(ALIGN(SSP_HEADER_SIZE, 4))
+
+static struct ssp_msg *ssp_create_msg(u8 cmd, u16 len, u16 opt, u32 data)
+{
+	struct ssp_msg_header h;
+	struct ssp_msg *msg;
+
+	msg = kzalloc(sizeof(*msg), GFP_KERNEL);
+	if (!msg)
+		return NULL;
+
+	h.cmd = cmd;
+	h.length = cpu_to_le16(len);
+	h.options = cpu_to_le16(opt);
+	h.data = cpu_to_le32(data);
+
+	msg->buffer = kzalloc(SSP_HEADER_SIZE_ALIGNED + len,
+			      GFP_KERNEL | GFP_DMA);
+	if (!msg->buffer) {
+		kfree(msg);
+		return NULL;
+	}
+
+	msg->length = len;
+	msg->options = opt;
+
+	memcpy(msg->buffer, &h, SSP_HEADER_SIZE);
+
+	return msg;
+}
+
+/*
+ * It is a bit heavy to do it this way but often the function is used to compose
+ * the message from smaller chunks which are placed on the stack.  Often the
+ * chunks are small so memcpy should be optimalized.
+ */
+static inline void ssp_fill_buffer(struct ssp_msg *m, unsigned int offset,
+				   const void *src, unsigned int len)
+{
+	memcpy(&m->buffer[SSP_HEADER_SIZE_ALIGNED + offset], src, len);
+}
+
+static inline void ssp_get_buffer(struct ssp_msg *m, unsigned int offset,
+				  void *dest, unsigned int len)
+{
+	memcpy(dest, &m->buffer[SSP_HEADER_SIZE_ALIGNED + offset],  len);
+}
+
+#define SSP_GET_BUFFER_AT_INDEX(m, index) \
+	(m->buffer[SSP_HEADER_SIZE_ALIGNED + index])
+#define SSP_SET_BUFFER_AT_INDEX(m, index, val) \
+	(m->buffer[SSP_HEADER_SIZE_ALIGNED + index] = val)
+
+static void ssp_clean_msg(struct ssp_msg *m)
+{
+	kfree(m->buffer);
+	kfree(m);
+}
+
+static int ssp_print_mcu_debug(char *data_frame, int *data_index,
+			       int received_len)
+{
+	int length = data_frame[(*data_index)++];
+
+	if (length > received_len - *data_index || length <= 0) {
+		ssp_dbg("[SSP]: MSG From MCU-invalid debug length(%d/%d)\n",
+			length, received_len);
+		return length ? length : -EPROTO;
+	}
+
+	ssp_dbg("[SSP]: MSG From MCU - %s\n", &data_frame[*data_index]);
+
+	*data_index += length;
+
+	return 0;
+}
+
+/*
+ * It was designed that way - additional lines to some kind of handshake,
+ * please do not ask why - only the firmware guy can know it.
+ */
+static int ssp_check_lines(struct ssp_data *data, bool state)
+{
+	int delay_cnt = 0;
+
+	gpio_set_value_cansleep(data->ap_mcu_gpio, state);
+
+	while (gpio_get_value_cansleep(data->mcu_ap_gpio) != state) {
+		usleep_range(3000, 3500);
+
+		if (data->shut_down || delay_cnt++ > 500) {
+			dev_err(SSP_DEV, "%s:timeout, hw ack wait fail %d\n",
+				__func__, state);
+
+			if (!state)
+				gpio_set_value_cansleep(data->ap_mcu_gpio, 1);
+
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+static int ssp_do_transfer(struct ssp_data *data, struct ssp_msg *msg,
+			   struct completion *done, int timeout)
+{
+	int status;
+	/*
+	 * check if this is a short one way message or the whole transfer has
+	 * second part after an interrupt
+	 */
+	const bool use_no_irq = msg->length == 0;
+
+	if (data->shut_down)
+		return -EPERM;
+
+	msg->done = done;
+
+	mutex_lock(&data->comm_lock);
+
+	status = ssp_check_lines(data, false);
+	if (status < 0)
+		goto _error_locked;
+
+	status = spi_write(data->spi, msg->buffer, SSP_HEADER_SIZE);
+	if (status < 0) {
+		gpio_set_value_cansleep(data->ap_mcu_gpio, 1);
+		dev_err(SSP_DEV, "%s spi_write fail\n", __func__);
+		goto _error_locked;
+	}
+
+	if (!use_no_irq) {
+		mutex_lock(&data->pending_lock);
+		list_add_tail(&msg->list, &data->pending_list);
+		mutex_unlock(&data->pending_lock);
+	}
+
+	status = ssp_check_lines(data, true);
+	if (status < 0) {
+		if (!use_no_irq) {
+			mutex_lock(&data->pending_lock);
+			list_del(&msg->list);
+			mutex_unlock(&data->pending_lock);
+		}
+		goto _error_locked;
+	}
+
+	mutex_unlock(&data->comm_lock);
+
+	if (!use_no_irq && done)
+		if (wait_for_completion_timeout(done,
+						msecs_to_jiffies(timeout)) ==
+		    0) {
+			mutex_lock(&data->pending_lock);
+			list_del(&msg->list);
+			mutex_unlock(&data->pending_lock);
+
+			data->timeout_cnt++;
+			return -ETIMEDOUT;
+		}
+
+	return 0;
+
+_error_locked:
+	mutex_unlock(&data->comm_lock);
+	data->timeout_cnt++;
+	return status;
+}
+
+static inline int ssp_spi_sync_command(struct ssp_data *data,
+				       struct ssp_msg *msg)
+{
+	return ssp_do_transfer(data, msg, NULL, 0);
+}
+
+static int ssp_spi_sync(struct ssp_data *data, struct ssp_msg *msg,
+			int timeout)
+{
+	DECLARE_COMPLETION_ONSTACK(done);
+
+	if (WARN_ON(!msg->length))
+		return -EPERM;
+
+	return ssp_do_transfer(data, msg, &done, timeout);
+}
+
+static int ssp_handle_big_data(struct ssp_data *data, char *dataframe, int *idx)
+{
+	/* mock-up, it will be changed with adding another sensor types */
+	*idx += 8;
+	return 0;
+}
+
+static int ssp_parse_dataframe(struct ssp_data *data, char *dataframe, int len)
+{
+	int idx, sd;
+	struct timespec ts;
+	struct ssp_sensor_data *spd;
+	struct iio_dev **indio_devs = data->sensor_devs;
+
+	getnstimeofday(&ts);
+
+	for (idx = 0; idx < len;) {
+		switch (dataframe[idx++]) {
+		case SSP_MSG2AP_INST_BYPASS_DATA:
+			sd = dataframe[idx++];
+			if (sd < 0 || sd >= SSP_SENSOR_MAX) {
+				dev_err(SSP_DEV,
+					"Mcu data frame1 error %d\n", sd);
+				return -EPROTO;
+			}
+
+			if (indio_devs[sd]) {
+				spd = iio_priv(indio_devs[sd]);
+				if (spd->process_data)
+					spd->process_data(indio_devs[sd],
+							  &dataframe[idx],
+							  data->timestamp);
+			} else {
+				dev_err(SSP_DEV, "no client for frame\n");
+			}
+
+			idx += ssp_offset_map[sd];
+			break;
+		case SSP_MSG2AP_INST_DEBUG_DATA:
+			sd = ssp_print_mcu_debug(dataframe, &idx, len);
+			if (sd) {
+				dev_err(SSP_DEV,
+					"Mcu data frame3 error %d\n", sd);
+				return sd;
+			}
+			break;
+		case SSP_MSG2AP_INST_LIBRARY_DATA:
+			idx += len;
+			break;
+		case SSP_MSG2AP_INST_BIG_DATA:
+			ssp_handle_big_data(data, dataframe, &idx);
+			break;
+		case SSP_MSG2AP_INST_TIME_SYNC:
+			data->time_syncing = true;
+			break;
+		case SSP_MSG2AP_INST_RESET:
+			ssp_queue_ssp_refresh_task(data, 0);
+			break;
+		}
+	}
+
+	if (data->time_syncing)
+		data->timestamp = ts.tv_sec * 1000000000ULL + ts.tv_nsec;
+
+	return 0;
+}
+
+/* threaded irq */
+int ssp_irq_msg(struct ssp_data *data)
+{
+	bool found = false;
+	char *buffer;
+	u8 msg_type;
+	int ret;
+	u16 length, msg_options;
+	struct ssp_msg *msg, *n;
+
+	ret = spi_read(data->spi, data->header_buffer, SSP_HEADER_BUFFER_SIZE);
+	if (ret < 0) {
+		dev_err(SSP_DEV, "header read fail\n");
+		return ret;
+	}
+
+	length = le16_to_cpu(data->header_buffer[1]);
+	msg_options = le16_to_cpu(data->header_buffer[0]);
+
+	if (length == 0) {
+		dev_err(SSP_DEV, "length received from mcu is 0\n");
+		return -EINVAL;
+	}
+
+	msg_type = SSP_GET_MESSAGE_TYPE(msg_options);
+
+	switch (msg_type) {
+	case SSP_AP2HUB_READ:
+	case SSP_AP2HUB_WRITE:
+		/*
+		 * this is a small list, a few elements - the packets can be
+		 * received with no order
+		 */
+		mutex_lock(&data->pending_lock);
+		list_for_each_entry_safe(msg, n, &data->pending_list, list) {
+			if (msg->options == msg_options) {
+				list_del(&msg->list);
+				found = true;
+				break;
+			}
+		}
+
+		if (!found) {
+			/*
+			 * here can be implemented dead messages handling
+			 * but the slave should not send such ones - it is to
+			 * check but let's handle this
+			 */
+			buffer = kmalloc(length, GFP_KERNEL | GFP_DMA);
+			if (!buffer) {
+				ret = -ENOMEM;
+				goto _unlock;
+			}
+
+			/* got dead packet so it is always an error */
+			ret = spi_read(data->spi, buffer, length);
+			if (ret >= 0)
+				ret = -EPROTO;
+
+			kfree(buffer);
+
+			dev_err(SSP_DEV, "No match error %x\n",
+				msg_options);
+
+			goto _unlock;
+		}
+
+		if (msg_type == SSP_AP2HUB_READ)
+			ret = spi_read(data->spi,
+				       &msg->buffer[SSP_HEADER_SIZE_ALIGNED],
+				       msg->length);
+
+		if (msg_type == SSP_AP2HUB_WRITE) {
+			ret = spi_write(data->spi,
+					&msg->buffer[SSP_HEADER_SIZE_ALIGNED],
+					msg->length);
+			if (msg_options & SSP_AP2HUB_RETURN) {
+				msg->options =
+					SSP_AP2HUB_READ | SSP_AP2HUB_RETURN;
+				msg->length = 1;
+
+				list_add_tail(&msg->list, &data->pending_list);
+				goto _unlock;
+			}
+		}
+
+		if (msg->done)
+			if (!completion_done(msg->done))
+				complete(msg->done);
+_unlock:
+		mutex_unlock(&data->pending_lock);
+		break;
+	case SSP_HUB2AP_WRITE:
+		buffer = kzalloc(length, GFP_KERNEL | GFP_DMA);
+		if (!buffer)
+			return -ENOMEM;
+
+		ret = spi_read(data->spi, buffer, length);
+		if (ret < 0) {
+			dev_err(SSP_DEV, "spi read fail\n");
+			kfree(buffer);
+			break;
+		}
+
+		ret = ssp_parse_dataframe(data, buffer, length);
+
+		kfree(buffer);
+		break;
+
+	default:
+		dev_err(SSP_DEV, "unknown msg type\n");
+		return -EPROTO;
+	}
+
+	return ret;
+}
+
+void ssp_clean_pending_list(struct ssp_data *data)
+{
+	struct ssp_msg *msg, *n;
+
+	mutex_lock(&data->pending_lock);
+	list_for_each_entry_safe(msg, n, &data->pending_list, list) {
+		list_del(&msg->list);
+
+		if (msg->done)
+			if (!completion_done(msg->done))
+				complete(msg->done);
+	}
+	mutex_unlock(&data->pending_lock);
+}
+
+int ssp_command(struct ssp_data *data, char command, int arg)
+{
+	int ret;
+	struct ssp_msg *msg;
+
+	msg = ssp_create_msg(command, 0, SSP_AP2HUB_WRITE, arg);
+	if (!msg)
+		return -ENOMEM;
+
+	ssp_dbg("%s - command 0x%x %d\n", __func__, command, arg);
+
+	ret = ssp_spi_sync_command(data, msg);
+	ssp_clean_msg(msg);
+
+	return ret;
+}
+
+int ssp_send_instruction(struct ssp_data *data, u8 inst, u8 sensor_type,
+			 u8 *send_buf, u8 length)
+{
+	int ret;
+	struct ssp_msg *msg;
+
+	if (data->fw_dl_state == SSP_FW_DL_STATE_DOWNLOADING) {
+		dev_err(SSP_DEV, "%s - Skip Inst! DL state = %d\n",
+			__func__, data->fw_dl_state);
+		return -EBUSY;
+	} else if (!(data->available_sensors & BIT(sensor_type)) &&
+		   (inst <= SSP_MSG2SSP_INST_CHANGE_DELAY)) {
+		dev_err(SSP_DEV, "%s - Bypass Inst Skip! - %u\n",
+			__func__, sensor_type);
+		return -EIO; /* just fail */
+	}
+
+	msg = ssp_create_msg(inst, length + 2, SSP_AP2HUB_WRITE, 0);
+	if (!msg)
+		return -ENOMEM;
+
+	ssp_fill_buffer(msg, 0, &sensor_type, 1);
+	ssp_fill_buffer(msg, 1, send_buf, length);
+
+	ssp_dbg("%s - Inst = 0x%x, Sensor Type = 0x%x, data = %u\n",
+		__func__, inst, sensor_type, send_buf[1]);
+
+	ret = ssp_spi_sync(data, msg, 1000);
+	ssp_clean_msg(msg);
+
+	return ret;
+}
+
+int ssp_get_chipid(struct ssp_data *data)
+{
+	int ret;
+	char buffer;
+	struct ssp_msg *msg;
+
+	msg = ssp_create_msg(SSP_MSG2SSP_AP_WHOAMI, 1, SSP_AP2HUB_READ, 0);
+	if (!msg)
+		return -ENOMEM;
+
+	ret = ssp_spi_sync(data, msg, 1000);
+
+	buffer = SSP_GET_BUFFER_AT_INDEX(msg, 0);
+
+	ssp_clean_msg(msg);
+
+	return ret < 0 ? ret : buffer;
+}
+
+int ssp_set_magnetic_matrix(struct ssp_data *data)
+{
+	int ret;
+	struct ssp_msg *msg;
+
+	msg = ssp_create_msg(SSP_MSG2SSP_AP_SET_MAGNETIC_STATIC_MATRIX,
+			     data->sensorhub_info->mag_length, SSP_AP2HUB_WRITE,
+			     0);
+	if (!msg)
+		return -ENOMEM;
+
+	ssp_fill_buffer(msg, 0, data->sensorhub_info->mag_table,
+			data->sensorhub_info->mag_length);
+
+	ret = ssp_spi_sync(data, msg, 1000);
+	ssp_clean_msg(msg);
+
+	return ret;
+}
+
+unsigned int ssp_get_sensor_scanning_info(struct ssp_data *data)
+{
+	int ret;
+	__le32 result;
+	u32 cpu_result = 0;
+
+	struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_SENSOR_SCANNING, 4,
+					     SSP_AP2HUB_READ, 0);
+	if (!msg)
+		return 0;
+
+	ret = ssp_spi_sync(data, msg, 1000);
+	if (ret < 0) {
+		dev_err(SSP_DEV, "%s - spi read fail %d\n", __func__, ret);
+		goto _exit;
+	}
+
+	ssp_get_buffer(msg, 0, &result, 4);
+	cpu_result = le32_to_cpu(result);
+
+	dev_info(SSP_DEV, "%s state: 0x%08x\n", __func__, cpu_result);
+
+_exit:
+	ssp_clean_msg(msg);
+	return cpu_result;
+}
+
+unsigned int ssp_get_firmware_rev(struct ssp_data *data)
+{
+	int ret;
+	__le32 result;
+
+	struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_FIRMWARE_REV, 4,
+					     SSP_AP2HUB_READ, 0);
+	if (!msg)
+		return SSP_INVALID_REVISION;
+
+	ret = ssp_spi_sync(data, msg, 1000);
+	if (ret < 0) {
+		dev_err(SSP_DEV, "%s - transfer fail %d\n", __func__, ret);
+		ret = SSP_INVALID_REVISION;
+		goto _exit;
+	}
+
+	ssp_get_buffer(msg, 0, &result, 4);
+	ret = le32_to_cpu(result);
+
+_exit:
+	ssp_clean_msg(msg);
+	return ret;
+}