]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/staging/greybus/spi.c
greybus: gbphy: Remove protocol specific version handling
[karo-tx-linux.git] / drivers / staging / greybus / spi.c
index 78a7f85a4bf65eebc245aea4813106583660c89b..a82337931c0d25af19fa4da98ae2a17da8510093 100644 (file)
 /*
- * 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;
-};
-
-/* Routines to transfer data */
-static struct gb_operation *
-gb_spi_operation_create(struct gb_connection *connection,
-                       struct spi_message *msg, u32 *total_len)
+static int gb_spi_probe(struct gbphy_device *gbphy_dev,
+                       const struct gbphy_device_id *id)
 {
-       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)
-{
-       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);
+       connection = gb_connection_create(gbphy_dev->bundle,
+                                         le16_to_cpu(gbphy_dev->cport_desc->id),
+                                         NULL);
+       if (IS_ERR(connection))
+               return PTR_ERR(connection);
 
-       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
-
-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;
-}
+               goto exit_connection_destroy;
 
-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;
-
-       ret = gb_operation_sync(spi->connection, GB_SPI_TYPE_BITS_PER_WORD_MASK,
-                               NULL, 0, &response, sizeof(response));
-       if (ret)
-               return ret;
-
-       spi->bits_per_word_mask = le32_to_cpu(response.bits_per_word_mask);
-
-       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));
+       ret = gb_spilib_master_init(connection, &gbphy_dev->dev);
        if (ret)
-               return ret;
+               goto exit_connection_disable;
 
-       spi->num_chipselect = le16_to_cpu(response.num_chipselect);
+       gb_gbphy_set_data(gbphy_dev, connection);
 
        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);
+
+static struct gbphy_driver spi_driver = {
+       .name           = "spi",
+       .probe          = gb_spi_probe,
+       .remove         = gb_spi_remove,
+       .id_table       = gb_spi_id_table,
 };
 
-gb_gpbridge_protocol_driver(spi_protocol);
+module_gbphy_driver(spi_driver);
+MODULE_LICENSE("GPL v2");