mirror of https://gitee.com/openkylin/linux.git
spi/bitbang: Factor out message transfer from message pump loop
In order to make it easier to convert to transfer_one_message() lift the code that does the actual message transfer out of the work function that implements the message pump. This should have no functional impact, it's just a simple code motion patch. Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Mark Brown
parent
874b315856
commit
91b3085867
|
|
@ -255,6 +255,112 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
|
||||||
* Drivers can provide word-at-a-time i/o primitives, or provide
|
* Drivers can provide word-at-a-time i/o primitives, or provide
|
||||||
* transfer-at-a-time ones to leverage dma or fifo hardware.
|
* transfer-at-a-time ones to leverage dma or fifo hardware.
|
||||||
*/
|
*/
|
||||||
|
static int spi_bitbang_transfer_one(struct spi_device *spi,
|
||||||
|
struct spi_message *m)
|
||||||
|
{
|
||||||
|
struct spi_bitbang *bitbang;
|
||||||
|
unsigned nsecs;
|
||||||
|
struct spi_transfer *t = NULL;
|
||||||
|
unsigned tmp;
|
||||||
|
unsigned cs_change;
|
||||||
|
int status;
|
||||||
|
int do_setup = -1;
|
||||||
|
|
||||||
|
bitbang = spi_master_get_devdata(spi->master);
|
||||||
|
|
||||||
|
/* FIXME this is made-up ... the correct value is known to
|
||||||
|
* word-at-a-time bitbang code, and presumably chipselect()
|
||||||
|
* should enforce these requirements too?
|
||||||
|
*/
|
||||||
|
nsecs = 100;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
cs_change = 1;
|
||||||
|
status = 0;
|
||||||
|
|
||||||
|
list_for_each_entry (t, &m->transfers, transfer_list) {
|
||||||
|
|
||||||
|
/* override speed or wordsize? */
|
||||||
|
if (t->speed_hz || t->bits_per_word)
|
||||||
|
do_setup = 1;
|
||||||
|
|
||||||
|
/* init (-1) or override (1) transfer params */
|
||||||
|
if (do_setup != 0) {
|
||||||
|
status = bitbang->setup_transfer(spi, t);
|
||||||
|
if (status < 0)
|
||||||
|
break;
|
||||||
|
if (do_setup == -1)
|
||||||
|
do_setup = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* set up default clock polarity, and activate chip;
|
||||||
|
* this implicitly updates clock and spi modes as
|
||||||
|
* previously recorded for this device via setup().
|
||||||
|
* (and also deselects any other chip that might be
|
||||||
|
* selected ...)
|
||||||
|
*/
|
||||||
|
if (cs_change) {
|
||||||
|
bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
|
||||||
|
ndelay(nsecs);
|
||||||
|
}
|
||||||
|
cs_change = t->cs_change;
|
||||||
|
if (!t->tx_buf && !t->rx_buf && t->len) {
|
||||||
|
status = -EINVAL;
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* transfer data. the lower level code handles any
|
||||||
|
* new dma mappings it needs. our caller always gave
|
||||||
|
* us dma-safe buffers.
|
||||||
|
*/
|
||||||
|
if (t->len) {
|
||||||
|
/* REVISIT dma API still needs a designated
|
||||||
|
* DMA_ADDR_INVALID; ~0 might be better.
|
||||||
|
*/
|
||||||
|
if (!m->is_dma_mapped)
|
||||||
|
t->rx_dma = t->tx_dma = 0;
|
||||||
|
status = bitbang->txrx_bufs(spi, t);
|
||||||
|
}
|
||||||
|
if (status > 0)
|
||||||
|
m->actual_length += status;
|
||||||
|
if (status != t->len) {
|
||||||
|
/* always report some kind of error */
|
||||||
|
if (status >= 0)
|
||||||
|
status = -EREMOTEIO;
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
status = 0;
|
||||||
|
|
||||||
|
/* protocol tweaks before next transfer */
|
||||||
|
if (t->delay_usecs)
|
||||||
|
udelay(t->delay_usecs);
|
||||||
|
|
||||||
|
if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
|
||||||
|
/* sometimes a short mid-message deselect of the chip
|
||||||
|
* may be needed to terminate a mode or command
|
||||||
|
*/
|
||||||
|
ndelay(nsecs);
|
||||||
|
bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
|
||||||
|
ndelay(nsecs);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
m->status = status;
|
||||||
|
m->complete(m->context);
|
||||||
|
|
||||||
|
/* normally deactivate chipselect ... unless no error and
|
||||||
|
* cs_change has hinted that the next message will probably
|
||||||
|
* be for this chip too.
|
||||||
|
*/
|
||||||
|
if (!(status == 0 && cs_change)) {
|
||||||
|
ndelay(nsecs);
|
||||||
|
bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
|
||||||
|
ndelay(nsecs);
|
||||||
|
}
|
||||||
|
|
||||||
|
return status;
|
||||||
|
}
|
||||||
|
|
||||||
static void bitbang_work(struct work_struct *work)
|
static void bitbang_work(struct work_struct *work)
|
||||||
{
|
{
|
||||||
struct spi_bitbang *bitbang =
|
struct spi_bitbang *bitbang =
|
||||||
|
|
@ -265,107 +371,10 @@ static void bitbang_work(struct work_struct *work)
|
||||||
spin_lock_irqsave(&bitbang->lock, flags);
|
spin_lock_irqsave(&bitbang->lock, flags);
|
||||||
bitbang->busy = 1;
|
bitbang->busy = 1;
|
||||||
list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
|
list_for_each_entry_safe(m, _m, &bitbang->queue, queue) {
|
||||||
struct spi_device *spi;
|
|
||||||
unsigned nsecs;
|
|
||||||
struct spi_transfer *t = NULL;
|
|
||||||
unsigned tmp;
|
|
||||||
unsigned cs_change;
|
|
||||||
int status;
|
|
||||||
int do_setup = -1;
|
|
||||||
|
|
||||||
list_del(&m->queue);
|
list_del(&m->queue);
|
||||||
spin_unlock_irqrestore(&bitbang->lock, flags);
|
spin_unlock_irqrestore(&bitbang->lock, flags);
|
||||||
|
|
||||||
/* FIXME this is made-up ... the correct value is known to
|
spi_bitbang_transfer_one(m->spi, m);
|
||||||
* word-at-a-time bitbang code, and presumably chipselect()
|
|
||||||
* should enforce these requirements too?
|
|
||||||
*/
|
|
||||||
nsecs = 100;
|
|
||||||
|
|
||||||
spi = m->spi;
|
|
||||||
tmp = 0;
|
|
||||||
cs_change = 1;
|
|
||||||
status = 0;
|
|
||||||
|
|
||||||
list_for_each_entry (t, &m->transfers, transfer_list) {
|
|
||||||
|
|
||||||
/* override speed or wordsize? */
|
|
||||||
if (t->speed_hz || t->bits_per_word)
|
|
||||||
do_setup = 1;
|
|
||||||
|
|
||||||
/* init (-1) or override (1) transfer params */
|
|
||||||
if (do_setup != 0) {
|
|
||||||
status = bitbang->setup_transfer(spi, t);
|
|
||||||
if (status < 0)
|
|
||||||
break;
|
|
||||||
if (do_setup == -1)
|
|
||||||
do_setup = 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* set up default clock polarity, and activate chip;
|
|
||||||
* this implicitly updates clock and spi modes as
|
|
||||||
* previously recorded for this device via setup().
|
|
||||||
* (and also deselects any other chip that might be
|
|
||||||
* selected ...)
|
|
||||||
*/
|
|
||||||
if (cs_change) {
|
|
||||||
bitbang->chipselect(spi, BITBANG_CS_ACTIVE);
|
|
||||||
ndelay(nsecs);
|
|
||||||
}
|
|
||||||
cs_change = t->cs_change;
|
|
||||||
if (!t->tx_buf && !t->rx_buf && t->len) {
|
|
||||||
status = -EINVAL;
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* transfer data. the lower level code handles any
|
|
||||||
* new dma mappings it needs. our caller always gave
|
|
||||||
* us dma-safe buffers.
|
|
||||||
*/
|
|
||||||
if (t->len) {
|
|
||||||
/* REVISIT dma API still needs a designated
|
|
||||||
* DMA_ADDR_INVALID; ~0 might be better.
|
|
||||||
*/
|
|
||||||
if (!m->is_dma_mapped)
|
|
||||||
t->rx_dma = t->tx_dma = 0;
|
|
||||||
status = bitbang->txrx_bufs(spi, t);
|
|
||||||
}
|
|
||||||
if (status > 0)
|
|
||||||
m->actual_length += status;
|
|
||||||
if (status != t->len) {
|
|
||||||
/* always report some kind of error */
|
|
||||||
if (status >= 0)
|
|
||||||
status = -EREMOTEIO;
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
status = 0;
|
|
||||||
|
|
||||||
/* protocol tweaks before next transfer */
|
|
||||||
if (t->delay_usecs)
|
|
||||||
udelay(t->delay_usecs);
|
|
||||||
|
|
||||||
if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
|
|
||||||
/* sometimes a short mid-message deselect of the chip
|
|
||||||
* may be needed to terminate a mode or command
|
|
||||||
*/
|
|
||||||
ndelay(nsecs);
|
|
||||||
bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
|
|
||||||
ndelay(nsecs);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
m->status = status;
|
|
||||||
m->complete(m->context);
|
|
||||||
|
|
||||||
/* normally deactivate chipselect ... unless no error and
|
|
||||||
* cs_change has hinted that the next message will probably
|
|
||||||
* be for this chip too.
|
|
||||||
*/
|
|
||||||
if (!(status == 0 && cs_change)) {
|
|
||||||
ndelay(nsecs);
|
|
||||||
bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
|
|
||||||
ndelay(nsecs);
|
|
||||||
}
|
|
||||||
|
|
||||||
spin_lock_irqsave(&bitbang->lock, flags);
|
spin_lock_irqsave(&bitbang->lock, flags);
|
||||||
}
|
}
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue