From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Thu, 20 Mar 2014 09:20:37 +0000 Subject: [PATCH v6 05/36] mtd: st_spi_fsm: Supply a method to read from the FSM's FIFO In-Reply-To: <1395307268-12721-1-git-send-email-lee.jones@linaro.org> References: <1395307268-12721-1-git-send-email-lee.jones@linaro.org> Message-ID: <1395307268-12721-6-git-send-email-lee.jones@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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. Acked-by Angus Clark Signed-off-by: Lee Jones --- drivers/mtd/devices/st_spi_fsm.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c index 5e22c86..73e0f27 100644 --- a/drivers/mtd/devices/st_spi_fsm.c +++ b/drivers/mtd/devices/st_spi_fsm.c @@ -281,6 +281,32 @@ 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; -- 1.8.3.2