Quite often the pattern used for setting up and transferring a synchronous SPI
transaction looks very much like the following:
struct spi_message msg;
struct spi_transfer xfers[] = {
...
};
spi_message_init(&msg);
spi_message_add_tail(&xfers[0], &msg);
...
spi_message_add_tail(&xfers[ARRAY_SIZE(xfers) - 1], &msg);
ret = spi_sync(&msg);
This patch adds two new helper functions for handling this case. The first
helper function spi_message_init_with_transfers() takes a spi_message and an
array of spi_transfers. It will initialize the message and then call
spi_message_add_tail() for each transfer in the array. E.g. the following
spi_message_init(&msg);
spi_message_add_tail(&xfers[0], &msg);
...
spi_message_add_tail(&xfers[ARRAY_SIZE(xfers) - 1], &msg);
can be rewritten as
spi_message_init_with_transfers(&msg, xfers, ARRAY_SIZE(xfers));
The second function spi_sync_transfer() takes a SPI device and an array of
spi_transfers. It will allocate a new spi_message (on the stack) and add all
transfers in the array to the message. Finally it will call spi_sync() on the
message.
E.g. the follwing
struct spi_message msg;
struct spi_transfer xfers[] = {
...
};
spi_message_init(&msg);
spi_message_add_tail(&xfers[0], &msg);
...
spi_message_add_tail(&xfers[ARRAY_SIZE(xfers) - 1], &msg);
ret = spi_sync(spi, &msg);
can be rewritten as
struct spi_transfer xfers[] = {
...
};
ret = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
A coccinelle script to find such instances will follow.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
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| .. | ||
| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| video | ||
| xen | ||
| Kbuild | ||