/*
- * SPI bridge driver for the Greybus "generic" SPI module.
+ * SPI bridge PHY driver.
*
- * Copyright 2014-2015 Google Inc.
- * Copyright 2014-2015 Linaro Ltd.
+ * Copyright 2014-2016 Google Inc.
+ * Copyright 2014-2016 Linaro Ltd.
*
* Released under the GPLv2 only.
*/
-#include <linux/bitops.h>
-#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/spi/spi.h>
#include "greybus.h"
+#include "gbphy.h"
+#include "spilib.h"
-struct gb_spi {
- struct gb_connection *connection;
- u16 mode;
- u16 flags;
- u32 bits_per_word_mask;
- u8 num_chipselect;
- u32 min_speed_hz;
- u32 max_speed_hz;
- struct spi_device *spi_devices;
-};
-
-static struct spi_master *get_master_from_spi(struct gb_spi *spi)
-{
- return spi->connection->private;
-}
-
-static int tx_header_fit_operation(u32 tx_size, u32 count, size_t data_max)
-{
- size_t headers_size;
-
- data_max -= sizeof(struct gb_spi_transfer_request);
- headers_size = (count + 1) * sizeof(struct gb_spi_transfer);
-
- return tx_size + headers_size > data_max ? 0 : 1;
-}
-
-static size_t calc_rx_xfer_size(u32 rx_size, u32 *tx_xfer_size, u32 len,
- size_t data_max)
-{
- size_t rx_xfer_size;
-
- data_max -= sizeof(struct gb_spi_transfer_response);
-
- if (rx_size + len > data_max)
- rx_xfer_size = data_max - rx_size;
- else
- rx_xfer_size = len;
-
- /* if this is a write_read, for symmetry read the same as write */
- if (*tx_xfer_size && rx_xfer_size > *tx_xfer_size)
- rx_xfer_size = *tx_xfer_size;
- if (*tx_xfer_size && rx_xfer_size < *tx_xfer_size)
- *tx_xfer_size = rx_xfer_size;
-
- return rx_xfer_size;
-}
-
-static size_t calc_tx_xfer_size(u32 tx_size, u32 count, size_t len,
- size_t data_max)
-{
- size_t headers_size;
-
- data_max -= sizeof(struct gb_spi_transfer_request);
- headers_size = (count + 1) * sizeof(struct gb_spi_transfer);
-
- if (tx_size + headers_size + len > data_max)
- return data_max - (tx_size + sizeof(struct gb_spi_transfer));
-
- return len;
-}
-
-/* Routines to transfer data */
-static struct gb_operation *
-gb_spi_operation_create(struct gb_connection *connection,
- struct spi_message *msg, u32 *total_len)
-{
- struct gb_spi_transfer_request *request;
- struct spi_device *dev = msg->spi;
- struct spi_transfer *xfer;
- struct gb_spi_transfer *gb_xfer;
- struct gb_operation *operation;
- struct spi_transfer *last_xfer = NULL;
- u32 tx_size = 0, rx_size = 0, count = 0, xfer_len = 0, request_size;
- u32 tx_xfer_size = 0, rx_xfer_size = 0, last_xfer_size = 0;
- size_t data_max;
- void *tx_data;
-
- data_max = gb_operation_get_payload_size_max(connection);
-
- /* Find number of transfers queued and tx/rx length in the message */
- list_for_each_entry(xfer, &msg->transfers, transfer_list) {
- if (!xfer->tx_buf && !xfer->rx_buf) {
- dev_err(&connection->bundle->dev,
- "bufferless transfer, length %u\n", xfer->len);
- return NULL;
- }
- last_xfer = xfer;
-
- tx_xfer_size = 0;
- rx_xfer_size = 0;
-
- if (xfer->tx_buf) {
- if (!tx_header_fit_operation(tx_size, count, data_max))
- break;
- tx_xfer_size = calc_tx_xfer_size(tx_size, count,
- xfer->len, data_max);
- last_xfer_size = tx_xfer_size;
- }
-
- if (xfer->rx_buf) {
- rx_xfer_size = calc_rx_xfer_size(rx_size, &tx_xfer_size,
- xfer->len, data_max);
- last_xfer_size = rx_xfer_size;
- }
-
- tx_size += tx_xfer_size;
- rx_size += rx_xfer_size;
-
- *total_len += last_xfer_size;
- count++;
-
- if (xfer->len != last_xfer_size)
- break;
- }
-
- /*
- * In addition to space for all message descriptors we need
- * to have enough to hold all tx data.
- */
- request_size = sizeof(*request);
- request_size += count * sizeof(*gb_xfer);
- request_size += tx_size;
-
- /* Response consists only of incoming data */
- operation = gb_operation_create(connection, GB_SPI_TYPE_TRANSFER,
- request_size, rx_size, GFP_KERNEL);
- if (!operation)
- return NULL;
-
- request = operation->request->payload;
- request->count = cpu_to_le16(count);
- request->mode = dev->mode;
- request->chip_select = dev->chip_select;
-
- gb_xfer = &request->transfers[0];
- tx_data = gb_xfer + count; /* place tx data after last gb_xfer */
-
- /* Fill in the transfers array */
- list_for_each_entry(xfer, &msg->transfers, transfer_list) {
- if (last_xfer && xfer == last_xfer)
- xfer_len = last_xfer_size;
- else
- xfer_len = xfer->len;
-
- gb_xfer->speed_hz = cpu_to_le32(xfer->speed_hz);
- gb_xfer->len = cpu_to_le32(xfer_len);
- gb_xfer->delay_usecs = cpu_to_le16(xfer->delay_usecs);
- gb_xfer->cs_change = xfer->cs_change;
- gb_xfer->bits_per_word = xfer->bits_per_word;
-
- /* Copy tx data */
- if (xfer->tx_buf) {
- gb_xfer->rdwr |= GB_SPI_XFER_WRITE;
- memcpy(tx_data, xfer->tx_buf, xfer_len);
- tx_data += xfer_len;
- }
-
- if (xfer->rx_buf)
- gb_xfer->rdwr |= GB_SPI_XFER_READ;
-
- if (last_xfer && xfer == last_xfer)
- break;
-
- gb_xfer++;
- }
-
- return operation;
-}
-
-static void gb_spi_decode_response(struct spi_message *msg,
- struct gb_spi_transfer_response *response)
-{
- struct spi_transfer *xfer;
- void *rx_data = response->data;
-
- list_for_each_entry(xfer, &msg->transfers, transfer_list) {
- /* Copy rx data */
- if (xfer->rx_buf) {
- memcpy(xfer->rx_buf, rx_data, xfer->len);
- rx_data += xfer->len;
- }
- }
-}
-
-static int gb_spi_transfer_one_message(struct spi_master *master,
- struct spi_message *msg)
-{
- struct gb_spi *spi = spi_master_get_devdata(master);
- struct gb_connection *connection = spi->connection;
- struct gb_spi_transfer_response *response;
- struct gb_operation *operation;
- u32 len = 0;
- int ret;
-
- operation = gb_spi_operation_create(connection, msg, &len);
- if (!operation)
- return -ENOMEM;
-
- ret = gb_operation_request_send_sync(operation);
- if (!ret) {
- response = operation->response->payload;
- if (response)
- gb_spi_decode_response(msg, response);
- } else {
- pr_err("transfer operation failed (%d)\n", ret);
- }
-
- gb_operation_put(operation);
-
- msg->actual_length = len;
- msg->status = 0;
- spi_finalize_current_message(master);
-
- return ret;
-}
-
-static int gb_spi_setup(struct spi_device *spi)
-{
- /* Nothing to do for now */
- return 0;
-}
-
-static void gb_spi_cleanup(struct spi_device *spi)
-{
- /* Nothing to do for now */
-}
-
-
-/* Routines to get controller information */
-
-/*
- * Map Greybus spi mode bits/flags/bpw into Linux ones.
- * All bits are same for now and so these macro's return same values.
- */
-#define gb_spi_mode_map(mode) mode
-#define gb_spi_flags_map(flags) flags
-
-static int gb_spi_get_master_config(struct gb_spi *spi)
-{
- struct gb_spi_master_config_response response;
- u16 mode, flags;
- int ret;
-
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_MASTER_CONFIG,
- NULL, 0, &response, sizeof(response));
- if (ret < 0)
- return ret;
-
- mode = le16_to_cpu(response.mode);
- spi->mode = gb_spi_mode_map(mode);
-
- flags = le16_to_cpu(response.flags);
- spi->flags = gb_spi_flags_map(flags);
-
- spi->bits_per_word_mask = le32_to_cpu(response.bits_per_word_mask);
- spi->num_chipselect = response.num_chipselect;
-
- spi->min_speed_hz = le32_to_cpu(response.min_speed_hz);
- spi->max_speed_hz = le32_to_cpu(response.max_speed_hz);
-
- return 0;
-}
-
-static int gb_spi_setup_device(struct gb_spi *spi, u8 cs)
+static int gb_spi_probe(struct gbphy_device *gbphy_dev,
+ const struct gbphy_device_id *id)
{
- struct spi_master *master = get_master_from_spi(spi);
- struct gb_spi_device_config_request request;
- struct gb_spi_device_config_response response;
- struct spi_board_info spi_board = { {0} };
- struct spi_device *spidev = &spi->spi_devices[cs];
+ struct gb_connection *connection;
int ret;
- request.chip_select = cs;
-
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_DEVICE_CONFIG,
- &request, sizeof(request),
- &response, sizeof(response));
- if (ret < 0)
- return ret;
-
- memcpy(spi_board.modalias, response.name, sizeof(spi_board.modalias));
- spi_board.mode = le16_to_cpu(response.mode);
- spi_board.bus_num = master->bus_num;
- spi_board.chip_select = cs;
- spi_board.max_speed_hz = le32_to_cpu(response.max_speed_hz);
-
- spidev = spi_new_device(master, &spi_board);
- if (!spidev)
- ret = -EINVAL;
-
- return 0;
-}
-
-static int gb_spi_init(struct gb_spi *spi)
-{
- int ret;
+ connection = gb_connection_create(gbphy_dev->bundle,
+ le16_to_cpu(gbphy_dev->cport_desc->id),
+ NULL);
+ if (IS_ERR(connection))
+ return PTR_ERR(connection);
- /* get master configuration */
- ret = gb_spi_get_master_config(spi);
+ ret = gb_connection_enable(connection);
if (ret)
- return ret;
-
- spi->spi_devices = kcalloc(spi->num_chipselect,
- sizeof(struct spi_device), GFP_KERNEL);
- if (!spi->spi_devices)
- return -ENOMEM;
-
- return ret;
-}
+ goto exit_connection_destroy;
-
-static int gb_spi_connection_init(struct gb_connection *connection)
-{
- struct gb_spi *spi;
- struct spi_master *master;
- int ret;
- u8 i;
-
- /* Allocate master with space for data */
- master = spi_alloc_master(&connection->bundle->dev, sizeof(*spi));
- if (!master) {
- dev_err(&connection->bundle->dev, "cannot alloc SPI master\n");
- return -ENOMEM;
- }
-
- spi = spi_master_get_devdata(master);
- spi->connection = connection;
- connection->private = master;
-
- ret = gb_spi_init(spi);
+ ret = gb_spilib_master_init(connection, &gbphy_dev->dev);
if (ret)
- goto out_put_master;
-
- master->bus_num = -1; /* Allow spi-core to allocate it dynamically */
- master->num_chipselect = spi->num_chipselect;
- master->mode_bits = spi->mode;
- master->flags = spi->flags;
- master->bits_per_word_mask = spi->bits_per_word_mask;
+ goto exit_connection_disable;
- /* Attach methods */
- master->cleanup = gb_spi_cleanup;
- master->setup = gb_spi_setup;
- master->transfer_one_message = gb_spi_transfer_one_message;
+ gb_gbphy_set_data(gbphy_dev, connection);
- ret = spi_register_master(master);
- if (ret < 0)
- goto out_put_master;
-
- /* now, fetch the devices configuration */
- for (i = 0; i < spi->num_chipselect; i++) {
- ret = gb_spi_setup_device(spi, i);
- if (ret < 0) {
- dev_err(&connection->bundle->dev,
- "failed to allocated spi device: %d\n", ret);
- spi_unregister_master(master);
- break;
- }
- }
-
- return ret;
+ return 0;
-out_put_master:
- spi_master_put(master);
+exit_connection_disable:
+ gb_connection_disable(connection);
+exit_connection_destroy:
+ gb_connection_destroy(connection);
return ret;
}
-static void gb_spi_connection_exit(struct gb_connection *connection)
+static void gb_spi_remove(struct gbphy_device *gbphy_dev)
{
- struct spi_master *master = connection->private;
+ struct gb_connection *connection = gb_gbphy_get_data(gbphy_dev);
- spi_unregister_master(master);
+ gb_spilib_master_exit(connection);
+ gb_connection_disable(connection);
+ gb_connection_destroy(connection);
}
-static struct gb_protocol spi_protocol = {
- .name = "spi",
- .id = GREYBUS_PROTOCOL_SPI,
- .major = GB_SPI_VERSION_MAJOR,
- .minor = GB_SPI_VERSION_MINOR,
- .connection_init = gb_spi_connection_init,
- .connection_exit = gb_spi_connection_exit,
- .request_recv = NULL,
+static const struct gbphy_device_id gb_spi_id_table[] = {
+ { GBPHY_PROTOCOL(GREYBUS_PROTOCOL_SPI) },
+ { },
+};
+MODULE_DEVICE_TABLE(gbphy, gb_spi_id_table);
+
+static struct gbphy_driver spi_driver = {
+ .name = "spi",
+ .probe = gb_spi_probe,
+ .remove = gb_spi_remove,
+ .id_table = gb_spi_id_table,
};
-gb_builtin_protocol_driver(spi_protocol);
+module_gbphy_driver(spi_driver);
+MODULE_LICENSE("GPL v2");
projects / karo-tx-linux.git / blobdiff