summaryrefslogtreecommitdiff
path: root/drivers/spi/spi.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r--drivers/spi/spi.c102
1 files changed, 76 insertions, 26 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7bc14fb309a6..a1ad8f41fb86 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -117,24 +117,28 @@ static struct spi_statistics __percpu *spi_alloc_pcpu_stats(struct device *dev)
return pcpu_stats;
}
-#define spi_pcpu_stats_totalize(ret, in, field) \
-do { \
- int i; \
- ret = 0; \
- for_each_possible_cpu(i) { \
- const struct spi_statistics *pcpu_stats; \
- u64 inc; \
- unsigned int start; \
- pcpu_stats = per_cpu_ptr(in, i); \
- do { \
- start = u64_stats_fetch_begin( \
- &pcpu_stats->syncp); \
- inc = u64_stats_read(&pcpu_stats->field); \
- } while (u64_stats_fetch_retry( \
- &pcpu_stats->syncp, start)); \
- ret += inc; \
- } \
-} while (0)
+static ssize_t spi_emit_pcpu_stats(struct spi_statistics __percpu *stat,
+ char *buf, size_t offset)
+{
+ u64 val = 0;
+ int i;
+
+ for_each_possible_cpu(i) {
+ const struct spi_statistics *pcpu_stats;
+ u64_stats_t *field;
+ unsigned int start;
+ u64 inc;
+
+ pcpu_stats = per_cpu_ptr(stat, i);
+ field = (void *)pcpu_stats + offset;
+ do {
+ start = u64_stats_fetch_begin(&pcpu_stats->syncp);
+ inc = u64_stats_read(field);
+ } while (u64_stats_fetch_retry(&pcpu_stats->syncp, start));
+ val += inc;
+ }
+ return sysfs_emit(buf, "%llu\n", val);
+}
#define SPI_STATISTICS_ATTRS(field, file) \
static ssize_t spi_controller_##field##_show(struct device *dev, \
@@ -165,11 +169,8 @@ static struct device_attribute dev_attr_spi_device_##field = { \
static ssize_t spi_statistics_##name##_show(struct spi_statistics __percpu *stat, \
char *buf) \
{ \
- ssize_t len; \
- u64 val; \
- spi_pcpu_stats_totalize(val, stat, field); \
- len = sysfs_emit(buf, "%llu\n", val); \
- return len; \
+ return spi_emit_pcpu_stats(stat, buf, \
+ offsetof(struct spi_statistics, field)); \
} \
SPI_STATISTICS_ATTRS(name, file)
@@ -2367,8 +2368,8 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc)
/* Store a pointer to the node in the device structure */
of_node_get(nc);
- spi->dev.of_node = nc;
- spi->dev.fwnode = of_fwnode_handle(nc);
+
+ device_set_node(&spi->dev, of_fwnode_handle(nc));
/* Register the new device */
rc = spi_add_device(spi);
@@ -3075,7 +3076,7 @@ static int spi_controller_check_ops(struct spi_controller *ctlr)
* If ->mem_ops or ->mem_ops->exec_op is NULL, we request that at least
* one of the ->transfer_xxx() method be implemented.
*/
- if (!ctlr->mem_ops || (ctlr->mem_ops && !ctlr->mem_ops->exec_op)) {
+ if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
if (!ctlr->transfer && !ctlr->transfer_one &&
!ctlr->transfer_one_message) {
return -EINVAL;
@@ -3621,6 +3622,55 @@ int spi_split_transfers_maxsize(struct spi_controller *ctlr,
}
EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize);
+
+/**
+ * spi_split_transfers_maxwords - split spi transfers into multiple transfers
+ * when an individual transfer exceeds a
+ * certain number of SPI words
+ * @ctlr: the @spi_controller for this transfer
+ * @msg: the @spi_message to transform
+ * @maxwords: the number of words to limit each transfer to
+ * @gfp: GFP allocation flags
+ *
+ * Return: status of transformation
+ */
+int spi_split_transfers_maxwords(struct spi_controller *ctlr,
+ struct spi_message *msg,
+ size_t maxwords,
+ gfp_t gfp)
+{
+ struct spi_transfer *xfer;
+
+ /*
+ * Iterate over the transfer_list,
+ * but note that xfer is advanced to the last transfer inserted
+ * to avoid checking sizes again unnecessarily (also xfer does
+ * potentially belong to a different list by the time the
+ * replacement has happened).
+ */
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ size_t maxsize;
+ int ret;
+
+ if (xfer->bits_per_word <= 8)
+ maxsize = maxwords;
+ else if (xfer->bits_per_word <= 16)
+ maxsize = 2 * maxwords;
+ else
+ maxsize = 4 * maxwords;
+
+ if (xfer->len > maxsize) {
+ ret = __spi_split_transfer_maxsize(ctlr, msg, &xfer,
+ maxsize, gfp);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(spi_split_transfers_maxwords);
+
/*-------------------------------------------------------------------------*/
/* Core methods for SPI controller protocol drivers. Some of the