diff mbox

[05/10] mtd: st_spi_fsm: Supply a method to read from the FSM's FIFO

Message ID 1384438956-31153-6-git-send-email-lee.jones@linaro.org
State New
Headers show

Commit Message

Lee Jones Nov. 14, 2013, 2:22 p.m. UTC
When invoked the driver will attempt to read any available data from
the FSM's data register. Any data collected from this FIFO would have
originated from the flash chip.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
 drivers/mtd/devices/st_spi_fsm.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
diff mbox

Patch

diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index 02619ee..a1c2857 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -94,6 +94,32 @@  static void stfsm_wait_seq(struct stfsm *fsm)
 	dev_err(fsm->dev, "timeout on sequence completion\n");
 }
 
+static void stfsm_read_fifo(struct stfsm *fsm, uint32_t *buf,
+			    const uint32_t size)
+{
+	uint32_t remaining = size >> 2;
+	uint32_t avail;
+	uint32_t words;
+
+	dev_dbg(fsm->dev, "Reading %d bytes from FIFO\n", size);
+
+	BUG_ON((((uint32_t)buf) & 0x3) || (size & 0x3));
+
+	while (remaining) {
+		for (;;) {
+			avail = stfsm_fifo_available(fsm);
+			if (avail)
+				break;
+			udelay(1);
+		}
+		words = min(avail, remaining);
+		remaining -= words;
+
+		readsl(fsm->base + SPI_FAST_SEQ_DATA_REG, buf, words);
+		buf += words;
+	}
+}
+
 static void stfsm_clear_fifo(struct stfsm *fsm)
 {
 	uint32_t avail;