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author | Lars-Peter Clausen <lars@metafoo.de> | 2013-01-09 17:31:00 (GMT) |
---|---|---|
committer | Jonathan Cameron <jic23@kernel.org> | 2013-02-09 11:02:07 (GMT) |
commit | 6d9eecd418afb2c12e5db5be3d72f0f1df43bdd9 (patch) | |
tree | 6c9fc5330e8e6970ab08f1c1220d612caeb44344 /drivers/pnp/isapnp/core.c | |
parent | ad76fda78318821fe8823b4b7c587a46a268eecf (diff) | |
download | linux-fsl-qoriq-6d9eecd418afb2c12e5db5be3d72f0f1df43bdd9.tar.xz |
spi: Add helper functions for setting up transfers
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>
Diffstat (limited to 'drivers/pnp/isapnp/core.c')
0 files changed, 0 insertions, 0 deletions