/*
- * SPI bridge driver for the Greybus "generic" SPI module.
+ * SPI bridge PHY driver.
*
- * Copyright 2014 Google Inc.
- * Copyright 2014 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;
- u8 version_major;
- u8 version_minor;
-
- /* Modes supported by spi controller */
- u16 mode;
- /* constraints of the spi controller */
- u16 flags;
-
- /*
- * copied from kernel:
- *
- * A mask indicating which values of bits_per_word are supported by the
- * controller. Bit n indicates that a bits_per_word n+1 is suported. If
- * set, the SPI core will reject any transfer with an unsupported
- * bits_per_word. If not set, this value is simply ignored, and it's up
- * to the individual driver to perform any validation.
- */
- u32 bits_per_word_mask;
-
- /*
- * chipselects will be integral to many controllers; some others might
- * use board-specific GPIOs.
- */
- u16 num_chipselect;
-};
-
-/* Version of the Greybus spi protocol we support */
-#define GB_SPI_VERSION_MAJOR 0x00
-#define GB_SPI_VERSION_MINOR 0x01
-
-/* Should match up with modes in linux/spi/spi.h */
-#define GB_SPI_MODE_CPHA 0x01 /* clock phase */
-#define GB_SPI_MODE_CPOL 0x02 /* clock polarity */
-#define GB_SPI_MODE_MODE_0 (0|0) /* (original MicroWire) */
-#define GB_SPI_MODE_MODE_1 (0|GB_SPI_MODE_CPHA)
-#define GB_SPI_MODE_MODE_2 (GB_SPI_MODE_CPOL|0)
-#define GB_SPI_MODE_MODE_3 (GB_SPI_MODE_CPOL|GB_SPI_MODE_CPHA)
-#define GB_SPI_MODE_CS_HIGH 0x04 /* chipselect active high? */
-#define GB_SPI_MODE_LSB_FIRST 0x08 /* per-word bits-on-wire */
-#define GB_SPI_MODE_3WIRE 0x10 /* SI/SO signals shared */
-#define GB_SPI_MODE_LOOP 0x20 /* loopback mode */
-#define GB_SPI_MODE_NO_CS 0x40 /* 1 dev/bus, no chipselect */
-#define GB_SPI_MODE_READY 0x80 /* slave pulls low to pause */
-
-/* Should match up with flags in linux/spi/spi.h */
-#define GB_SPI_FLAG_HALF_DUPLEX BIT(0) /* can't do full duplex */
-#define GB_SPI_FLAG_NO_RX BIT(1) /* can't do buffer read */
-#define GB_SPI_FLAG_NO_TX BIT(2) /* can't do buffer write */
-
-/* Greybus spi request types */
-#define GB_SPI_TYPE_INVALID 0x00
-#define GB_SPI_TYPE_PROTOCOL_VERSION 0x01
-#define GB_SPI_TYPE_MODE 0x02
-#define GB_SPI_TYPE_FLAGS 0x03
-#define GB_SPI_TYPE_BITS_PER_WORD_MASK 0x04
-#define GB_SPI_TYPE_NUM_CHIPSELECT 0x05
-#define GB_SPI_TYPE_TRANSFER 0x06
-#define GB_SPI_TYPE_RESPONSE 0x80 /* OR'd with rest */
-
-/* mode request has no payload */
-struct gb_spi_mode_response {
- __le16 mode;
-};
-
-/* flags request has no payload */
-struct gb_spi_flags_response {
- __le16 flags;
-};
-
-/* bits-per-word request has no payload */
-struct gb_spi_bpw_response {
- __le32 bits_per_word_mask;
-};
-
-/* num-chipselects request has no payload */
-struct gb_spi_chipselect_response {
- __le16 num_chipselect;
-};
-
-/**
- * struct gb_spi_transfer - a read/write buffer pair
- * @speed_hz: Select a speed other than the device default for this transfer. If
- * 0 the default (from @spi_device) is used.
- * @len: size of rx and tx buffers (in bytes)
- * @delay_usecs: microseconds to delay after this transfer before (optionally)
- * changing the chipselect status, then starting the next transfer or
- * completing this spi_message.
- * @cs_change: affects chipselect after this transfer completes
- * @bits_per_word: select a bits_per_word other than the device default for this
- * transfer. If 0 the default (from @spi_device) is used.
- */
-struct gb_spi_transfer {
- __le32 speed_hz;
- __le32 len;
- __le16 delay_usecs;
- __u8 cs_change;
- __u8 bits_per_word;
-};
-
-struct gb_spi_transfer_request {
- __u8 chip_select; /* of the spi device */
- __u8 mode; /* of the spi device */
- __le16 count;
- struct gb_spi_transfer transfers[0]; /* trnasfer_count of these */
-};
-
-struct gb_spi_transfer_response {
- __u8 data[0]; /* inbound data */
-};
-
-/* 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;
- u32 tx_size = 0, rx_size = 0, count = 0, request_size;
- void *tx_data;
-
- /* 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->dev,
- "bufferless transfer, length %u\n", xfer->len);
- return NULL;
- }
-
- if (xfer->tx_buf)
- tx_size += xfer->len;
- if (xfer->rx_buf)
- rx_size += xfer->len;
-
- *total_len += xfer->len;
- count++;
- }
-
- /* Too many transfers ? */
- if (count > (u32)U16_MAX) {
- dev_err(&connection->dev, "transfer count (%u) too big\n",
- count);
- return NULL;
- }
-
- /*
- * 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);
- 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) {
- 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;
- gb_xfer++;
-
- /* Copy tx data */
- if (xfer->tx_buf) {
- memcpy(tx_data, xfer->tx_buf, xfer->len);
- tx_data += xfer->len;
- }
- }
-
- return operation;
-}
-
-static void gb_spi_decode_response(struct spi_message *msg,
- struct gb_spi_transfer_response *response)
+static int gb_spi_probe(struct gbphy_device *gbphy_dev,
+ const struct gbphy_device_id *id)
{
- 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;
+ struct gb_connection *connection;
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_destroy(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 infomation */
-
-/* Define get_version() routine */
-define_get_version(gb_spi, SPI);
-
-/*
- * 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
+ connection = gb_connection_create(gbphy_dev->bundle,
+ le16_to_cpu(gbphy_dev->cport_desc->id),
+ NULL);
+ if (IS_ERR(connection))
+ return PTR_ERR(connection);
-static int gb_spi_mode_operation(struct gb_spi *spi)
-{
- struct gb_spi_mode_response response;
- u16 mode;
- int ret;
-
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_MODE,
- NULL, 0, &response, sizeof(response));
+ ret = gb_connection_enable(connection);
if (ret)
- return ret;
-
- mode = le16_to_cpu(response.mode);
- spi->mode = gb_spi_mode_map(mode);
-
- return 0;
-}
-
-static int gb_spi_flags_operation(struct gb_spi *spi)
-{
- struct gb_spi_flags_response response;
- u16 flags;
- int ret;
-
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_FLAGS,
- NULL, 0, &response, sizeof(response));
- if (ret)
- return ret;
-
- flags = le16_to_cpu(response.flags);
- spi->flags = gb_spi_flags_map(flags);
-
- return 0;
-}
-
-static int gb_spi_bpw_operation(struct gb_spi *spi)
-{
- struct gb_spi_bpw_response response;
- int ret;
+ goto exit_connection_destroy;
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_BITS_PER_WORD_MASK,
- NULL, 0, &response, sizeof(response));
+ ret = gb_spilib_master_init(connection, &gbphy_dev->dev);
if (ret)
- return ret;
+ goto exit_connection_disable;
- spi->bits_per_word_mask = le32_to_cpu(response.bits_per_word_mask);
+ gb_gbphy_set_data(gbphy_dev, connection);
return 0;
-}
-static int gb_spi_chipselect_operation(struct gb_spi *spi)
-{
- struct gb_spi_chipselect_response response;
- int ret;
-
- ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_NUM_CHIPSELECT,
- NULL, 0, &response, sizeof(response));
- if (ret)
- return ret;
-
- spi->num_chipselect = le16_to_cpu(response.num_chipselect);
-
- return 0;
-}
-
-/*
- * Initialize the spi device. This includes verifying we can support it (based
- * on the protocol version it advertises). If that's OK, we get and cached its
- * mode bits & flags.
- */
-static int gb_spi_init(struct gb_spi *spi)
-{
- int ret;
-
- /* First thing we need to do is check the version */
- ret = get_version(spi);
- if (ret)
- return ret;
-
- /* mode never changes, just get it once */
- ret = gb_spi_mode_operation(spi);
- if (ret)
- return ret;
-
- /* flags never changes, just get it once */
- ret = gb_spi_flags_operation(spi);
- if (ret)
- return ret;
-
- /* total number of chipselects never changes, just get it once */
- ret = gb_spi_chipselect_operation(spi);
- if (ret)
- return ret;
-
- /* bits-per-word-mask never changes, just get it once */
- return gb_spi_bpw_operation(spi);
-}
-
-static int gb_spi_connection_init(struct gb_connection *connection)
-{
- struct gb_spi *spi;
- struct spi_master *master;
- int ret;
-
- /* Allocate master with space for data */
- master = spi_alloc_master(&connection->dev, sizeof(*spi));
- if (!master) {
- dev_err(&connection->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);
- if (ret)
- goto out_err;
-
- master->bus_num = 0; /* How do we get controller id here? */
- 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;
-
- /* Attach methods */
- master->cleanup = gb_spi_cleanup;
- master->setup = gb_spi_setup;
- master->transfer_one_message = gb_spi_transfer_one_message;
-
- ret = spi_register_master(master);
- if (!ret)
- return 0;
-
-out_err:
- 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 = 0,
- .minor = 1,
- .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);
-int gb_spi_protocol_init(void)
-{
- return gb_protocol_register(&spi_protocol);
-}
+static struct gbphy_driver spi_driver = {
+ .name = "spi",
+ .probe = gb_spi_probe,
+ .remove = gb_spi_remove,
+ .id_table = gb_spi_id_table,
+};
-void gb_spi_protocol_exit(void)
-{
- gb_protocol_deregister(&spi_protocol);
-}
+module_gbphy_driver(spi_driver);
+MODULE_LICENSE("GPL v2");