spi->controller_state = state;
}
+/* device driver data */
+
+static inline void spi_set_drvdata(struct spi_device *spi, void *data)
+{
+ dev_set_drvdata(&spi->dev, data);
+}
+
+static inline void *spi_get_drvdata(struct spi_device *spi)
+{
+ return dev_get_drvdata(&spi->dev);
+}
struct spi_message;
static inline void spi_unregister_driver(struct spi_driver *sdrv)
{
- if (!sdrv)
- return;
- driver_unregister(&sdrv->driver);
+ if (sdrv)
+ driver_unregister(&sdrv->driver);
}
-
/**
* struct spi_master - interface to SPI master controller
* @cdev: class interface to this driver
* each slave has a chipselect signal, but it's common that not
* every chipselect is connected to a slave.
* @setup: updates the device mode and clocking records used by a
- * device's SPI controller; protocol code may call this.
+ * device's SPI controller; protocol code may call this. This
+ * must fail if an unrecognized or unsupported mode is requested.
* @transfer: adds a message to the controller's transfer queue.
* @cleanup: frees controller-specific state
*
* message's completion function when the transaction completes.
*/
struct spi_master {
- struct device dev;
+ struct class_device cdev;
/* other than negative (== assign one dynamically), bus_num is fully
* board-specific. usually that simplifies to being SOC-specific.
struct spi_message *mesg);
/* called on release() to free memory provided by spi_master */
- void (*cleanup)(const struct spi_device *spi);
+ void (*cleanup)(struct spi_device *spi);
};
static inline void *spi_master_get_devdata(struct spi_master *master)
{
- return dev_get_drvdata(&master->dev);
+ return class_get_devdata(&master->cdev);
}
static inline void spi_master_set_devdata(struct spi_master *master, void *data)
{
- dev_set_drvdata(&master->dev, data);
+ class_set_devdata(&master->cdev, data);
}
static inline struct spi_master *spi_master_get(struct spi_master *master)
{
- if (!master || !get_device(&master->dev))
+ if (!master || !class_device_get(&master->cdev))
return NULL;
return master;
}
static inline void spi_master_put(struct spi_master *master)
{
if (master)
- put_device(&master->dev);
+ class_device_put(&master->cdev);
}
* shifting out three bytes with word size of sixteen or twenty bits;
* the former uses two bytes per word, the latter uses four bytes.)
*
+ * In-memory data values are always in native CPU byte order, translated
+ * from the wire byte order (big-endian except with SPI_LSB_FIRST). So
+ * for example when bits_per_word is sixteen, buffers are 2N bytes long
+ * and hold N sixteen bit words in CPU byte order.
+ *
+ * When the word size of the SPI transfer is not a power-of-two multiple
+ * of eight bits, those in-memory words include extra bits. In-memory
+ * words are always seen by protocol drivers as right-justified, so the
+ * undefined (rx) or unused (tx) bits are always the most significant bits.
+ *
* All SPI transfers start with the relevant chipselect active. Normally
* it stays selected until after the last transfer in a message. Drivers
* can affect the chipselect signal using cs_change:
* changes those settings, and must be called from a context that can sleep.
* The changes take effect the next time the device is selected and data
* is transferred to or from it.
+ *
+ * Note that this call wil fail if the protocol driver specifies an option
+ * that the underlying controller or its driver does not support. For
+ * example, not all hardware supports wire transfers using nine bit words,
+ * LSB-first wire encoding, or active-high chipselects.
*/
static inline int
spi_setup(struct spi_device *spi)