spi: spi-mem: add statistics support to ->exec_op() calls

[linux-2.6-microblaze.git] / drivers / spi / spi-mem.c

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 2dc8ceb..c9d6d42 100644 (file)
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -297,6 +297,49 @@ static void spi_mem_access_end(struct spi_mem *mem)
                pm_runtime_put(ctlr->dev.parent);
 }
 
+static void spi_mem_add_op_stats(struct spi_statistics __percpu *pcpu_stats,
+                                const struct spi_mem_op *op, int exec_op_ret)
+{
+       struct spi_statistics *stats;
+       u64 len, l2len;
+
+       get_cpu();
+       stats = this_cpu_ptr(pcpu_stats);
+       u64_stats_update_begin(&stats->syncp);
+
+       /*
+        * We do not have the concept of messages or transfers. Let's consider
+        * that one operation is equivalent to one message and one transfer.
+        */
+       u64_stats_inc(&stats->messages);
+       u64_stats_inc(&stats->transfers);
+
+       /* Use the sum of all lengths as bytes count and histogram value. */
+       len = op->cmd.nbytes + op->addr.nbytes;
+       len += op->dummy.nbytes + op->data.nbytes;
+       u64_stats_add(&stats->bytes, len);
+       l2len = min(fls(len), SPI_STATISTICS_HISTO_SIZE) - 1;
+       u64_stats_inc(&stats->transfer_bytes_histo[l2len]);
+
+       /* Only account for data bytes as transferred bytes. */
+       if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
+               u64_stats_add(&stats->bytes_tx, op->data.nbytes);
+       if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN)
+               u64_stats_add(&stats->bytes_rx, op->data.nbytes);
+
+       /*
+        * A timeout is not an error, following the same behavior as
+        * spi_transfer_one_message().
+        */
+       if (exec_op_ret == -ETIMEDOUT)
+               u64_stats_inc(&stats->timedout);
+       else if (exec_op_ret)
+               u64_stats_inc(&stats->errors);
+
+       u64_stats_update_end(&stats->syncp);
+       put_cpu();
+}
+
 /**
  * spi_mem_exec_op() - Execute a memory operation
  * @mem: the SPI memory
@@ -339,8 +382,12 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
                 * read path) and expect the core to use the regular SPI
                 * interface in other cases.
                 */
-               if (!ret || ret != -ENOTSUPP || ret != -EOPNOTSUPP)
+               if (!ret || ret != -ENOTSUPP || ret != -EOPNOTSUPP) {
+                       spi_mem_add_op_stats(ctlr->pcpu_statistics, op, ret);
+                       spi_mem_add_op_stats(mem->spi->pcpu_statistics, op, ret);
+
                        return ret;
+               }
        }
 
        tmpbufsize = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;