From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Thu, 14 Nov 2013 14:22:31 +0000 Subject: [PATCH 05/10] mtd: st_spi_fsm: Supply a method to read from the FSM's FIFO In-Reply-To: <1384438956-31153-1-git-send-email-lee.jones@linaro.org> References: <1384438956-31153-1-git-send-email-lee.jones@linaro.org> Message-ID: <1384438956-31153-6-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. 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 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; -- 1.8.1.2