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Merge remote-tracking branch 'spi/topic/bitbang' into spi-next

hifive-unleashed-5.1
Mark Brown 2013-09-01 13:48:44 +01:00
parent c3dbe2b76a 2e29db400c
commit b29bc3df37
5 changed files with 115 additions and 195 deletions
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12
drivers/spi/spi-altera.c
View File

@ -103,16 +103,6 @@ static void altera_spi_chipsel(struct spi_device *spi, int value)
}
}
static int altera_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t)
{
return 0;
}
static int altera_spi_setup(struct spi_device *spi)
{
return 0;
}
static inline unsigned int hw_txbyte(struct altera_spi *hw, int count)
{
if (hw->tx) {
@ -224,7 +214,6 @@ static int altera_spi_probe(struct platform_device *pdev)
master->bus_num = pdev->id;
master->num_chipselect = 16;
master->mode_bits = SPI_CS_HIGH;
master->setup = altera_spi_setup;
hw = spi_master_get_devdata(master);
platform_set_drvdata(pdev, hw);
@ -233,7 +222,6 @@ static int altera_spi_probe(struct platform_device *pdev)
hw->bitbang.master = spi_master_get(master);
if (!hw->bitbang.master)
return err;
hw->bitbang.setup_transfer = altera_spi_setupxfer;
hw->bitbang.chipselect = altera_spi_chipsel;
hw->bitbang.txrx_bufs = altera_spi_txrx;

264
drivers/spi/spi-bitbang.c
View File

@ -255,150 +255,140 @@ 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
* transfer-at-a-time ones to leverage dma or fifo hardware.
*/
static void bitbang_work(struct work_struct *work)
static int spi_bitbang_prepare_hardware(struct spi_master *spi)
{
struct spi_bitbang *bitbang =
container_of(work, struct spi_bitbang, work);
struct spi_bitbang *bitbang;
unsigned long flags;
struct spi_message *m, *_m;
bitbang = spi_master_get_devdata(spi);
spin_lock_irqsave(&bitbang->lock, flags);
bitbang->busy = 1;
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;
spin_unlock_irqrestore(&bitbang->lock, flags);
list_del(&m->queue);
spin_unlock_irqrestore(&bitbang->lock, flags);
return 0;
}
/* 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;
static int spi_bitbang_transfer_one(struct spi_master *master,
struct spi_message *m)
{
struct spi_bitbang *bitbang;
unsigned nsecs;
struct spi_transfer *t = NULL;
unsigned cs_change;
int status;
int do_setup = -1;
struct spi_device *spi = m->spi;
spi = m->spi;
tmp = 0;
cs_change = 1;
status = 0;
bitbang = spi_master_get_devdata(master);
list_for_each_entry (t, &m->transfers, transfer_list) {
/* 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;
/* override speed or wordsize? */
if (t->speed_hz || t->bits_per_word)
do_setup = 1;
cs_change = 1;
status = 0;
/* 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;
}
list_for_each_entry (t, &m->transfers, transfer_list) {
/* 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;
/* 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;
}
/* 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);
}
if (do_setup == -1)
do_setup = 0;
}
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.
/* 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 (!(status == 0 && cs_change)) {
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);
}
spin_lock_irqsave(&bitbang->lock, flags);
}
bitbang->busy = 0;
spin_unlock_irqrestore(&bitbang->lock, flags);
}
/**
* spi_bitbang_transfer - default submit to transfer queue
*/
int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m)
{
struct spi_bitbang *bitbang;
unsigned long flags;
int status = 0;
m->status = status;
m->actual_length = 0;
m->status = -EINPROGRESS;
bitbang = spi_master_get_devdata(spi->master);
spin_lock_irqsave(&bitbang->lock, flags);
if (!spi->max_speed_hz)
status = -ENETDOWN;
else {
list_add_tail(&m->queue, &bitbang->queue);
queue_work(bitbang->workqueue, &bitbang->work);
/* 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_unlock_irqrestore(&bitbang->lock, flags);
spi_finalize_current_message(master);
return status;
}
EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
static int spi_bitbang_unprepare_hardware(struct spi_master *spi)
{
struct spi_bitbang *bitbang;
unsigned long flags;
bitbang = spi_master_get_devdata(spi);
spin_lock_irqsave(&bitbang->lock, flags);
bitbang->busy = 0;
spin_unlock_irqrestore(&bitbang->lock, flags);
return 0;
}
/*----------------------------------------------------------------------*/
@ -428,20 +418,22 @@ EXPORT_SYMBOL_GPL(spi_bitbang_transfer);
int spi_bitbang_start(struct spi_bitbang *bitbang)
{
struct spi_master *master = bitbang->master;
int status;
if (!master || !bitbang->chipselect)
return -EINVAL;
INIT_WORK(&bitbang->work, bitbang_work);
spin_lock_init(&bitbang->lock);
INIT_LIST_HEAD(&bitbang->queue);
if (!master->mode_bits)
master->mode_bits = SPI_CPOL | SPI_CPHA | bitbang->flags;
if (!master->transfer)
master->transfer = spi_bitbang_transfer;
if (master->transfer || master->transfer_one_message)
return -EINVAL;
master->prepare_transfer_hardware = spi_bitbang_prepare_hardware;
master->unprepare_transfer_hardware = spi_bitbang_unprepare_hardware;
master->transfer_one_message = spi_bitbang_transfer_one;
if (!bitbang->txrx_bufs) {
bitbang->use_dma = 0;
bitbang->txrx_bufs = spi_bitbang_bufs;
@ -452,34 +444,12 @@ int spi_bitbang_start(struct spi_bitbang *bitbang)
master->setup = spi_bitbang_setup;
master->cleanup = spi_bitbang_cleanup;
}
} else if (!master->setup)
return -EINVAL;
if (master->transfer == spi_bitbang_transfer &&
!bitbang->setup_transfer)
return -EINVAL;
/* this task is the only thing to touch the SPI bits */
bitbang->busy = 0;
bitbang->workqueue = create_singlethread_workqueue(
dev_name(master->dev.parent));
if (bitbang->workqueue == NULL) {
status = -EBUSY;
goto err1;
}
/* driver may get busy before register() returns, especially
* if someone registered boardinfo for devices
*/
status = spi_register_master(master);
if (status < 0)
goto err2;
return status;
err2:
destroy_workqueue(bitbang->workqueue);
err1:
return status;
return spi_register_master(master);
}
EXPORT_SYMBOL_GPL(spi_bitbang_start);
@ -490,10 +460,6 @@ int spi_bitbang_stop(struct spi_bitbang *bitbang)
{
spi_unregister_master(bitbang->master);
WARN_ON(!list_empty(&bitbang->queue));
destroy_workqueue(bitbang->workqueue);
return 0;
}
EXPORT_SYMBOL_GPL(spi_bitbang_stop);

13
drivers/spi/spi-nuc900.c
View File

@ -174,17 +174,6 @@ static void nuc900_spi_gobusy(struct nuc900_spi *hw)
spin_unlock_irqrestore(&hw->lock, flags);
}
static int nuc900_spi_setupxfer(struct spi_device *spi,
struct spi_transfer *t)
{
return 0;
}
static int nuc900_spi_setup(struct spi_device *spi)
{
return 0;
}
static inline unsigned int hw_txbyte(struct nuc900_spi *hw, int count)
{
return hw->tx ? hw->tx[count] : 0;
@ -377,10 +366,8 @@ static int nuc900_spi_probe(struct platform_device *pdev)
master->num_chipselect = hw->pdata->num_cs;
master->bus_num = hw->pdata->bus_num;
hw->bitbang.master = hw->master;
hw->bitbang.setup_transfer = nuc900_spi_setupxfer;
hw->bitbang.chipselect = nuc900_spi_chipsel;
hw->bitbang.txrx_bufs = nuc900_spi_txrx;
hw->bitbang.master->setup = nuc900_spi_setup;
hw->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (hw->res == NULL) {

16
drivers/spi/spi-xilinx.c
View File

@ -233,21 +233,6 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi,
return 0;
}
static int xilinx_spi_setup(struct spi_device *spi)
{
/* always return 0, we can not check the number of bits.
* There are cases when SPI setup is called before any driver is
* there, in that case the SPI core defaults to 8 bits, which we
* do not support in some cases. But if we return an error, the
* SPI device would not be registered and no driver can get hold of it
* When the driver is there, it will call SPI setup again with the
* correct number of bits per transfer.
* If a driver setups with the wrong bit number, it will fail when
* it tries to do a transfer
*/
return 0;
}
static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi)
{
u8 sr;
@ -375,7 +360,6 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem,
xspi->bitbang.chipselect = xilinx_spi_chipselect;
xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer;
xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs;
xspi->bitbang.master->setup = xilinx_spi_setup;
init_completion(&xspi->done);
if (!request_mem_region(mem->start, resource_size(mem),

5
include/linux/spi/spi_bitbang.h
View File

@ -4,11 +4,7 @@
#include <linux/workqueue.h>
struct spi_bitbang {
struct workqueue_struct *workqueue;
struct work_struct work;
spinlock_t lock;
struct list_head queue;
u8 busy;
u8 use_dma;
u8 flags; /* extra spi->mode support */
@ -41,7 +37,6 @@ struct spi_bitbang {
*/
extern int spi_bitbang_setup(struct spi_device *spi);
extern void spi_bitbang_cleanup(struct spi_device *spi);
extern int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m);
extern int spi_bitbang_setup_transfer(struct spi_device *spi,
struct spi_transfer *t);