/* Nothing to do here */
break;
case SPI_DELAY_UNIT_SCK:
- /* clock cycles need to be obtained from spi_transfer */
+ /* Clock cycles need to be obtained from spi_transfer */
if (!xfer)
return -EINVAL;
/*
u32 unit = xfer->cs_change_delay.unit;
int ret;
- /* return early on "fast" mode - for everything but USECS */
+ /* Return early on "fast" mode - for everything but USECS */
if (!delay) {
if (unit == SPI_DELAY_UNIT_USECS)
_spi_transfer_delay_ns(default_delay_ns);
WRITE_ONCE(ctlr->cur_msg_incomplete, true);
WRITE_ONCE(ctlr->cur_msg_need_completion, false);
reinit_completion(&ctlr->cur_msg_completion);
- smp_wmb(); /* make these available to spi_finalize_current_message */
+ smp_wmb(); /* Make these available to spi_finalize_current_message() */
ret = ctlr->transfer_one_message(ctlr, msg);
if (ret) {
struct spi_message *next;
unsigned long flags;
- /* get a pointer to the next message, if any */
+ /* Get a pointer to the next message, if any */
spin_lock_irqsave(&ctlr->queue_lock, flags);
next = list_first_entry_or_null(&ctlr->queue, struct spi_message,
queue);
acpi_dev_free_resource_list(&resource_list);
if (ret < 0)
- /* found SPI in _CRS but it points to another controller */
+ /* Found SPI in _CRS but it points to another controller */
return ERR_PTR(-ENODEV);
if (!lookup.max_speed_hz &&
return status;
if (ctlr->bus_num >= 0) {
- /* devices with a fixed bus num must check-in with the num */
+ /* Devices with a fixed bus num must check-in with the num */
mutex_lock(&board_lock);
id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num,
ctlr->bus_num + 1, GFP_KERNEL);
return id == -ENOSPC ? -EBUSY : id;
ctlr->bus_num = id;
} else if (ctlr->dev.of_node) {
- /* allocate dynamic bus number using Linux idr */
+ /* Allocate dynamic bus number using Linux idr */
id = of_alias_get_id(ctlr->dev.of_node, "spi");
if (id >= 0) {
ctlr->bus_num = id;
goto free_bus_id;
}
- /* setting last_cs to -1 means no chip selected */
+ /* Setting last_cs to -1 means no chip selected */
ctlr->last_cs = -1;
status = device_add(&ctlr->dev);
goto free_bus_id;
}
}
- /* add statistics */
+ /* Add statistics */
ctlr->pcpu_statistics = spi_alloc_pcpu_stats(dev);
if (!ctlr->pcpu_statistics) {
dev_err(dev, "Error allocating per-cpu statistics\n");
device_del(&ctlr->dev);
- /* free bus id */
+ /* Free bus id */
mutex_lock(&board_lock);
if (found == ctlr)
idr_remove(&spi_master_idr, id);
struct spi_replaced_transfers *rxfer = res;
size_t i;
- /* call extra callback if requested */
+ /* Call extra callback if requested */
if (rxfer->release)
rxfer->release(ctlr, msg, res);
- /* insert replaced transfers back into the message */
+ /* Insert replaced transfers back into the message */
list_splice(&rxfer->replaced_transfers, rxfer->replaced_after);
- /* remove the formerly inserted entries */
+ /* Remove the formerly inserted entries */
for (i = 0; i < rxfer->inserted; i++)
list_del(&rxfer->inserted_transfers[i].transfer_list);
}
struct spi_transfer *xfer;
size_t i;
- /* allocate the structure using spi_res */
+ /* Allocate the structure using spi_res */
rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release,
struct_size(rxfer, inserted_transfers, insert)
+ extradatasize,
if (!rxfer)
return ERR_PTR(-ENOMEM);
- /* the release code to invoke before running the generic release */
+ /* The release code to invoke before running the generic release */
rxfer->release = release;
- /* assign extradata */
+ /* Assign extradata */
if (extradatasize)
rxfer->extradata =
&rxfer->inserted_transfers[insert];
- /* init the replaced_transfers list */
+ /* Init the replaced_transfers list */
INIT_LIST_HEAD(&rxfer->replaced_transfers);
/*
*/
rxfer->replaced_after = xfer_first->transfer_list.prev;
- /* remove the requested number of transfers */
+ /* Remove the requested number of transfers */
for (i = 0; i < remove; i++) {
/*
* If the entry after replaced_after it is msg->transfers
if (rxfer->replaced_after->next == &msg->transfers) {
dev_err(&msg->spi->dev,
"requested to remove more spi_transfers than are available\n");
- /* insert replaced transfers back into the message */
+ /* Insert replaced transfers back into the message */
list_splice(&rxfer->replaced_transfers,
rxfer->replaced_after);
- /* free the spi_replace_transfer structure */
+ /* Free the spi_replace_transfer structure... */
spi_res_free(rxfer);
- /* and return with an error */
+ /* ...and return with an error */
return ERR_PTR(-EINVAL);
}
* based on the first transfer to get removed.
*/
for (i = 0; i < insert; i++) {
- /* we need to run in reverse order */
+ /* We need to run in reverse order */
xfer = &rxfer->inserted_transfers[insert - 1 - i];
- /* copy all spi_transfer data */
+ /* Copy all spi_transfer data */
memcpy(xfer, xfer_first, sizeof(*xfer));
- /* add to list */
+ /* Add to list */
list_add(&xfer->transfer_list, rxfer->replaced_after);
- /* clear cs_change and delay for all but the last */
+ /* Clear cs_change and delay for all but the last */
if (i) {
xfer->cs_change = false;
xfer->delay.value = 0;
}
}
- /* set up inserted */
+ /* Set up inserted... */
rxfer->inserted = insert;
- /* and register it with spi_res/spi_message */
+ /* ...and register it with spi_res/spi_message */
spi_res_add(msg, rxfer);
return rxfer;
size_t offset;
size_t count, i;
- /* calculate how many we have to replace */
+ /* Calculate how many we have to replace */
count = DIV_ROUND_UP(xfer->len, maxsize);
- /* create replacement */
+ /* Create replacement */
srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp);
if (IS_ERR(srt))
return PTR_ERR(srt);
*/
xfers[0].len = min_t(size_t, maxsize, xfer[0].len);
- /* all the others need rx_buf/tx_buf also set */
+ /* All the others need rx_buf/tx_buf also set */
for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) {
- /* update rx_buf, tx_buf and dma */
+ /* Update rx_buf, tx_buf and dma */
if (xfers[i].rx_buf)
xfers[i].rx_buf += offset;
if (xfers[i].rx_dma)
if (xfers[i].tx_dma)
xfers[i].tx_dma += offset;
- /* update length */
+ /* Update length */
xfers[i].len = min(maxsize, xfers[i].len - offset);
}
*/
*xferp = &xfers[count - 1];
- /* increment statistics counters */
+ /* Increment statistics counters */
SPI_STATISTICS_INCREMENT_FIELD(ctlr->pcpu_statistics,
transfers_split_maxsize);
SPI_STATISTICS_INCREMENT_FIELD(msg->spi->pcpu_statistics,
return ret;
list_for_each_entry(xfer, &message->transfers, transfer_list) {
- /* don't change cs_change on the last entry in the list */
+ /* Don't change cs_change on the last entry in the list */
if (list_is_last(&xfer->transfer_list, &message->transfers))
break;
xfer->cs_change = 1;
!(spi->mode & SPI_TX_QUAD))
return -EINVAL;
}
- /* check transfer rx_nbits */
+ /* Check transfer rx_nbits */
if (xfer->rx_buf) {
if (spi->mode & SPI_NO_RX)
return -EINVAL;
ctlr->bus_lock_flag = 1;
spin_unlock_irqrestore(&ctlr->bus_lock_spinlock, flags);
- /* mutex remains locked until spi_bus_unlock is called */
+ /* Mutex remains locked until spi_bus_unlock() is called */
return 0;
}
}
EXPORT_SYMBOL_GPL(spi_bus_unlock);
-/* portable code must never pass more than 32 bytes */
+/* Portable code must never pass more than 32 bytes */
#define SPI_BUFSIZ max(32, SMP_CACHE_BYTES)
static u8 *buf;
x[0].tx_buf = local_buf;
x[1].rx_buf = local_buf + n_tx;
- /* do the i/o */
+ /* Do the i/o */
status = spi_sync(spi, &message);
if (status == 0)
memcpy(rxbuf, x[1].rx_buf, n_rx);
/*-------------------------------------------------------------------------*/
#if IS_ENABLED(CONFIG_OF_DYNAMIC)
-/* must call put_device() when done with returned spi_device device */
+/* Must call put_device() when done with returned spi_device device */
static struct spi_device *of_find_spi_device_by_node(struct device_node *node)
{
struct device *dev = bus_find_device_by_of_node(&spi_bus_type, node);
return dev ? to_spi_device(dev) : NULL;
}
-/* the spi controllers are not using spi_bus, so we find it with another way */
+/* The spi controllers are not using spi_bus, so we find it with another way */
static struct spi_controller *of_find_spi_controller_by_node(struct device_node *node)
{
struct device *dev;
if (!dev)
return NULL;
- /* reference got in class_find_device */
+ /* Reference got in class_find_device */
return container_of(dev, struct spi_controller, dev);
}
case OF_RECONFIG_CHANGE_ADD:
ctlr = of_find_spi_controller_by_node(rd->dn->parent);
if (ctlr == NULL)
- return NOTIFY_OK; /* not for us */
+ return NOTIFY_OK; /* Not for us */
if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
put_device(&ctlr->dev);
break;
case OF_RECONFIG_CHANGE_REMOVE:
- /* already depopulated? */
+ /* Already depopulated? */
if (!of_node_check_flag(rd->dn, OF_POPULATED))
return NOTIFY_OK;
- /* find our device by node */
+ /* Find our device by node */
spi = of_find_spi_device_by_node(rd->dn);
if (spi == NULL)
- return NOTIFY_OK; /* no? not meant for us */
+ return NOTIFY_OK; /* No? not meant for us */
- /* unregister takes one ref away */
+ /* Unregister takes one ref away */
spi_unregister_device(spi);
- /* and put the reference of the find */
+ /* And put the reference of the find */
put_device(&spi->dev);
break;
}
struct spi_device {
struct device dev;
struct spi_controller *controller;
- struct spi_controller *master; /* compatibility layer */
+ struct spi_controller *master; /* Compatibility layer */
u32 max_speed_hz;
u8 chip_select;
u8 bits_per_word;
bool rt;
-#define SPI_NO_TX BIT(31) /* no transmit wire */
-#define SPI_NO_RX BIT(30) /* no receive wire */
+#define SPI_NO_TX BIT(31) /* No transmit wire */
+#define SPI_NO_RX BIT(30) /* No receive wire */
/*
* All bits defined above should be covered by SPI_MODE_KERNEL_MASK.
* The SPI_MODE_KERNEL_MASK has the SPI_MODE_USER_MASK counterpart,
void *controller_data;
char modalias[SPI_NAME_SIZE];
const char *driver_override;
- struct gpio_desc *cs_gpiod; /* chip select gpio desc */
- struct spi_delay word_delay; /* inter-word delay */
+ struct gpio_desc *cs_gpiod; /* Chip select gpio desc */
+ struct spi_delay word_delay; /* Inter-word delay */
/* CS delays */
struct spi_delay cs_setup;
struct spi_delay cs_hold;
struct spi_delay cs_inactive;
- /* the statistics */
+ /* The statistics */
struct spi_statistics __percpu *pcpu_statistics;
/*
return dev ? container_of(dev, struct spi_device, dev) : NULL;
}
-/* most drivers won't need to care about device refcounting */
+/* Most drivers won't need to care about device refcounting */
static inline struct spi_device *spi_dev_get(struct spi_device *spi)
{
return (spi && get_device(&spi->dev)) ? spi : NULL;
spi->controller_state = state;
}
-/* device driver data */
+/* Device driver data */
static inline void spi_set_drvdata(struct spi_device *spi, void *data)
{
extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 chip_select);
-/* use a define to avoid include chaining to get THIS_MODULE */
+/* Use a define to avoid include chaining to get THIS_MODULE */
#define spi_register_driver(driver) \
__spi_register_driver(THIS_MODULE, driver)
struct list_head list;
- /* other than negative (== assign one dynamically), bus_num is fully
+ /* Other than negative (== assign one dynamically), bus_num is fully
* board-specific. usually that simplifies to being SOC-specific.
* example: one SOC has three SPI controllers, numbered 0..2,
* and one board's schematics might show it using SPI-2. software
*/
u16 num_chipselect;
- /* some SPI controllers pose alignment requirements on DMAable
+ /* Some SPI controllers pose alignment requirements on DMAable
* buffers; let protocol drivers know about these requirements.
*/
u16 dma_alignment;
/* spi_device.mode flags override flags for this controller */
u32 buswidth_override_bits;
- /* bitmask of supported bits_per_word for transfers */
+ /* Bitmask of supported bits_per_word for transfers */
u32 bits_per_word_mask;
#define SPI_BPW_MASK(bits) BIT((bits) - 1)
#define SPI_BPW_RANGE_MASK(min, max) GENMASK((max) - 1, (min) - 1)
- /* limits on transfer speed */
+ /* Limits on transfer speed */
u32 min_speed_hz;
u32 max_speed_hz;
- /* other constraints relevant to this driver */
+ /* Other constraints relevant to this driver */
u16 flags;
-#define SPI_CONTROLLER_HALF_DUPLEX BIT(0) /* can't do full duplex */
-#define SPI_CONTROLLER_NO_RX BIT(1) /* can't do buffer read */
-#define SPI_CONTROLLER_NO_TX BIT(2) /* can't do buffer write */
-#define SPI_CONTROLLER_MUST_RX BIT(3) /* requires rx */
-#define SPI_CONTROLLER_MUST_TX BIT(4) /* requires tx */
+#define SPI_CONTROLLER_HALF_DUPLEX BIT(0) /* Can't do full duplex */
+#define SPI_CONTROLLER_NO_RX BIT(1) /* Can't do buffer read */
+#define SPI_CONTROLLER_NO_TX BIT(2) /* Can't do buffer write */
+#define SPI_CONTROLLER_MUST_RX BIT(3) /* Requires rx */
+#define SPI_CONTROLLER_MUST_TX BIT(4) /* Requires tx */
#define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */
- /* flag indicating if the allocation of this struct is devres-managed */
+ /* Flag indicating if the allocation of this struct is devres-managed */
bool devm_allocated;
- /* flag indicating this is an SPI slave controller */
+ /* Flag indicating this is an SPI slave controller */
bool slave;
/*
/* Used to avoid adding the same CS twice */
struct mutex add_lock;
- /* lock and mutex for SPI bus locking */
+ /* Lock and mutex for SPI bus locking */
spinlock_t bus_lock_spinlock;
struct mutex bus_lock_mutex;
- /* flag indicating that the SPI bus is locked for exclusive use */
+ /* Flag indicating that the SPI bus is locked for exclusive use */
bool bus_lock_flag;
/* Setup mode and clock, etc (spi driver may call many times).
*/
int (*set_cs_timing)(struct spi_device *spi);
- /* bidirectional bulk transfers
+ /* Bidirectional bulk transfers
*
* + The transfer() method may not sleep; its main role is
* just to add the message to the queue.
int (*transfer)(struct spi_device *spi,
struct spi_message *mesg);
- /* called on release() to free memory provided by spi_controller */
+ /* Called on release() to free memory provided by spi_controller */
void (*cleanup)(struct spi_device *spi);
/*
s8 unused_native_cs;
s8 max_native_cs;
- /* statistics */
+ /* Statistics */
struct spi_statistics __percpu *pcpu_statistics;
/* DMA channels for use with core dmaengine helpers */
struct dma_chan *dma_tx;
struct dma_chan *dma_rx;
- /* dummy data for full duplex devices */
+ /* Dummy data for full duplex devices */
void *dummy_rx;
void *dummy_tx;
struct spi_transfer *xfer,
size_t progress, bool irqs_off);
-/* the spi driver core manages memory for the spi_controller classdev */
+/* The spi driver core manages memory for the spi_controller classdev */
extern struct spi_controller *__spi_alloc_controller(struct device *host,
unsigned int size, bool slave);
struct spi_res {
struct list_head entry;
spi_res_release_t release;
- unsigned long long data[]; /* guarantee ull alignment */
+ unsigned long long data[]; /* Guarantee ull alignment */
};
/*---------------------------------------------------------------------------*/
* and its transfers, ignore them until its completion callback.
*/
struct spi_transfer {
- /* it's ok if tx_buf == rx_buf (right?)
+ /* It's ok if tx_buf == rx_buf (right?)
* for MicroWire, one buffer must be null
* buffers must work with dma_*map_single() calls, unless
* spi_message.is_dma_mapped reports a pre-existing mapping
* tell them about such special cases.
*/
- /* completion is reported through a callback */
+ /* Completion is reported through a callback */
void (*complete)(void *context);
void *context;
unsigned frame_length;
unsigned actual_length;
int status;
- /* for optional use by whatever driver currently owns the
+ /* For optional use by whatever driver currently owns the
* spi_message ... between calls to spi_async and then later
* complete(), that's the spi_controller controller driver.
*/
struct list_head queue;
void *state;
- /* list of spi_res reources when the spi message is processed */
+ /* List of spi_res reources when the spi message is processed */
struct list_head resources;
- /* spi_prepare_message was called for this message */
+ /* spi_prepare_message() was called for this message */
bool prepared;
};
if (ctlr->max_transfer_size)
tr_max = ctlr->max_transfer_size(spi);
- /* transfer size limit must not be greater than message size limit */
+ /* Transfer size limit must not be greater than message size limit */
return min(tr_max, msg_max);
}
return spi_sync_transfer(spi, &t, 1);
}
-/* this copies txbuf and rxbuf data; for small transfers only! */
+/* This copies txbuf and rxbuf data; for small transfers only! */
extern int spi_write_then_read(struct spi_device *spi,
const void *txbuf, unsigned n_tx,
void *rxbuf, unsigned n_rx);
status = spi_write_then_read(spi, &cmd, 1, &result, 1);
- /* return negative errno or unsigned value */
+ /* Return negative errno or unsigned value */
return (status < 0) ? status : result;
}
status = spi_write_then_read(spi, &cmd, 1, &result, 2);
- /* return negative errno or unsigned value */
+ /* Return negative errno or unsigned value */
return (status < 0) ? status : result;
}
* are active in some dynamic board configuration models.
*/
struct spi_board_info {
- /* the device name and module name are coupled, like platform_bus;
+ /* The device name and module name are coupled, like platform_bus;
* "modalias" is normally the driver name.
*
* platform_data goes to spi_device.dev.platform_data,
void *controller_data;
int irq;
- /* slower signaling on noisy or low voltage boards */
+ /* Slower signaling on noisy or low voltage boards */
u32 max_speed_hz;
extern int
spi_register_board_info(struct spi_board_info const *info, unsigned n);
#else
-/* board init code may ignore whether SPI is configured or not */
+/* Board init code may ignore whether SPI is configured or not */
static inline int
spi_register_board_info(struct spi_board_info const *info, unsigned n)
{ return 0; }
git.samba.org / sfrench / cifs-2.6.git / commitdiff