Split off a transport mechanism struct that will deal with the SPI
traffic in preparation for adding I2C support.
Tested-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
ChangeLog v1->v2:
- Staticize the SPI accessors to avoid noise when compiling
with all warnings.
- Fix up the interim stage kerneldoc to match the movement
of tx, rx and the introduced transport struct.
---
drivers/iio/accel/kxsd9.c | 175 ++++++++++++++++++++++++++++++++--------------
1 file changed, 123 insertions(+), 52 deletions(-)
diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c
index 9d72d4bcf5e9..df8a31e84c7d 100644
--- a/drivers/iio/accel/kxsd9.c
+++ b/drivers/iio/accel/kxsd9.c
@@ -43,18 +43,36 @@
#define KXSD9_STATE_RX_SIZE 2
#define KXSD9_STATE_TX_SIZE 2
+
+struct kxsd9_transport;
+
+/**
+ * struct kxsd9_transport - transport adapter for SPI or I2C
+ * @trdev: transport device such as SPI or I2C
+ * @write1(): function to write a byte to the device
+ * @write2(): function to write two consecutive bytes to the device
+ * @readval(): function to read a 16bit value from the device
+ * @rx: cache aligned read buffer
+ * @tx: cache aligned write buffer
+ */
+struct kxsd9_transport {
+ void *trdev;
+ int (*write1) (struct kxsd9_transport *tr, u8 byte);
+ int (*write2) (struct kxsd9_transport *tr, u8 b1, u8 b2);
+ int (*readval) (struct kxsd9_transport *tr, u8 address);
+ u8 rx[KXSD9_STATE_RX_SIZE] ____cacheline_aligned;
+ u8 tx[KXSD9_STATE_TX_SIZE];
+};
+
/**
* struct kxsd9_state - device related storage
+ * @transport: transport for the KXSD9
* @buf_lock: protect the rx and tx buffers.
* @us: spi device
- * @rx: single rx buffer storage
- * @tx: single tx buffer storage
**/
struct kxsd9_state {
+ struct kxsd9_transport *transport;
struct mutex buf_lock;
- struct spi_device *us;
- u8 rx[KXSD9_STATE_RX_SIZE] ____cacheline_aligned;
- u8 tx[KXSD9_STATE_TX_SIZE];
};
#define KXSD9_SCALE_2G "0.011978"
@@ -80,13 +98,12 @@ static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
return -EINVAL;
mutex_lock(&st->buf_lock);
- ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C));
- if (ret < 0)
+ ret = st->transport->write1(st->transport, KXSD9_READ(KXSD9_REG_CTRL_C));
+ if (ret)
goto error_ret;
- st->tx[0] = KXSD9_WRITE(KXSD9_REG_CTRL_C);
- st->tx[1] = (ret & ~KXSD9_FS_MASK) | i;
-
- ret = spi_write(st->us, st->tx, 2);
+ ret = st->transport->write2(st->transport,
+ KXSD9_WRITE(KXSD9_REG_CTRL_C),
+ (ret & ~KXSD9_FS_MASK) | i);
error_ret:
mutex_unlock(&st->buf_lock);
return ret;
@@ -96,24 +113,9 @@ static int kxsd9_read(struct iio_dev *indio_dev, u8 address)
{
int ret;
struct kxsd9_state *st = iio_priv(indio_dev);
- struct spi_transfer xfers[] = {
- {
- .bits_per_word = 8,
- .len = 1,
- .delay_usecs = 200,
- .tx_buf = st->tx,
- }, {
- .bits_per_word = 8,
- .len = 2,
- .rx_buf = st->rx,
- },
- };
mutex_lock(&st->buf_lock);
- st->tx[0] = KXSD9_READ(address);
- ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
- if (!ret)
- ret = (((u16)(st->rx[0])) << 8) | (st->rx[1] & 0xF0);
+ ret = st->transport->readval(st->transport, KXSD9_READ(address));
mutex_unlock(&st->buf_lock);
return ret;
}
@@ -163,8 +165,8 @@ static int kxsd9_read_raw(struct iio_dev *indio_dev,
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_SCALE:
- ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C));
- if (ret < 0)
+ ret = st->transport->write1(st->transport, KXSD9_READ(KXSD9_REG_CTRL_C));
+ if (ret)
goto error_ret;
*val = 0;
*val2 = kxsd9_micro_scales[ret & KXSD9_FS_MASK];
@@ -203,15 +205,10 @@ static int kxsd9_power_up(struct kxsd9_state *st)
{
int ret;
- st->tx[0] = 0x0d;
- st->tx[1] = 0x40;
- ret = spi_write(st->us, st->tx, 2);
+ ret = st->transport->write2(st->transport, 0x0d, 0x40);
if (ret)
return ret;
-
- st->tx[0] = 0x0c;
- st->tx[1] = 0x9b;
- return spi_write(st->us, st->tx, 2);
+ return st->transport->write2(st->transport, 0x0c, 0x9b);
};
static const struct iio_info kxsd9_info = {
@@ -221,56 +218,130 @@ static const struct iio_info kxsd9_info = {
.driver_module = THIS_MODULE,
};
-static int kxsd9_probe(struct spi_device *spi)
+static int kxsd9_common_probe(struct device *parent,
+ struct kxsd9_transport *transport,
+ const char *name,
+ struct iio_dev **retdev)
{
struct iio_dev *indio_dev;
struct kxsd9_state *st;
+ int ret;
- indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ indio_dev = devm_iio_device_alloc(parent, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
- spi_set_drvdata(spi, indio_dev);
+ st->transport = transport;
- st->us = spi;
mutex_init(&st->buf_lock);
indio_dev->channels = kxsd9_channels;
indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
- indio_dev->name = spi_get_device_id(spi)->name;
- indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = name;
+ indio_dev->dev.parent = parent;
indio_dev->info = &kxsd9_info;
indio_dev->modes = INDIO_DIRECT_MODE;
+ kxsd9_power_up(st);
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ return ret;
+
+ *retdev = indio_dev;
+ return 0;
+}
+
+static int kxsd9_spi_write1(struct kxsd9_transport *tr, u8 byte)
+{
+ struct spi_device *spi = tr->trdev;
+
+ return spi_w8r8(spi, byte);
+}
+
+static int kxsd9_spi_write2(struct kxsd9_transport *tr, u8 b1, u8 b2)
+{
+ struct spi_device *spi = tr->trdev;
+
+ tr->tx[0] = b1;
+ tr->tx[1] = b2;
+ return spi_write(spi, tr->tx, 2);
+}
+
+static int kxsd9_spi_readval(struct kxsd9_transport *tr, u8 address)
+{
+ struct spi_device *spi = tr->trdev;
+ struct spi_transfer xfers[] = {
+ {
+ .bits_per_word = 8,
+ .len = 1,
+ .delay_usecs = 200,
+ .tx_buf = tr->tx,
+ }, {
+ .bits_per_word = 8,
+ .len = 2,
+ .rx_buf = tr->rx,
+ },
+ };
+ int ret;
+
+ tr->tx[0] = address;
+ ret = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
+ if (!ret)
+ ret = (((u16)(tr->rx[0])) << 8) | (tr->rx[1] & 0xF0);
+ return ret;
+}
+
+static int kxsd9_spi_probe(struct spi_device *spi)
+{
+ struct kxsd9_transport *transport;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ transport = devm_kzalloc(&spi->dev, sizeof(*transport), GFP_KERNEL);
+ if (!transport)
+ return -ENOMEM;
+
+ transport->trdev = spi;
+ transport->write1 = kxsd9_spi_write1;
+ transport->write2 = kxsd9_spi_write2;
+ transport->readval = kxsd9_spi_readval;
spi->mode = SPI_MODE_0;
spi_setup(spi);
- kxsd9_power_up(st);
- return iio_device_register(indio_dev);
+ ret = kxsd9_common_probe(&spi->dev,
+ transport,
+ spi_get_device_id(spi)->name,
+ &indio_dev);
+ if (ret)
+ return ret;
+
+ spi_set_drvdata(spi, indio_dev);
+ return 0;
}
-static int kxsd9_remove(struct spi_device *spi)
+static int kxsd9_spi_remove(struct spi_device *spi)
{
iio_device_unregister(spi_get_drvdata(spi));
return 0;
}
-static const struct spi_device_id kxsd9_id[] = {
+static const struct spi_device_id kxsd9_spi_id[] = {
{"kxsd9", 0},
{ },
};
-MODULE_DEVICE_TABLE(spi, kxsd9_id);
+MODULE_DEVICE_TABLE(spi, kxsd9_spi_id);
-static struct spi_driver kxsd9_driver = {
+static struct spi_driver kxsd9_spi_driver = {
.driver = {
.name = "kxsd9",
},
- .probe = kxsd9_probe,
- .remove = kxsd9_remove,
- .id_table = kxsd9_id,
+ .probe = kxsd9_spi_probe,
+ .remove = kxsd9_spi_remove,
+ .id_table = kxsd9_spi_id,
};
-module_spi_driver(kxsd9_driver);
+module_spi_driver(kxsd9_spi_driver);
MODULE_AUTHOR("Jonathan Cameron <jic23@xxxxxxxxxx>");
MODULE_DESCRIPTION("Kionix KXSD9 SPI driver");
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
