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[v4,05/37] mtd: st_spi_fsm: Supply a method to read from the FSM's FIFO

Message ID 1389188840-14306-6-git-send-email-lee.jones@linaro.org
State New
Headers show

Commit Message

Lee Jones Jan. 8, 2014, 1:46 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(+)
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Patch

diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index c7daeca..0eba759 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -274,6 +274,32 @@  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 int stfsm_set_mode(struct stfsm *fsm, uint32_t mode)
 {
 	int ret, timeout = 10;