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authorOlof Johansson <olof@lixom.net>2015-04-03 13:38:43 -0700
committerOlof Johansson <olof@lixom.net>2015-04-03 13:38:43 -0700
commit47f36e4921ae11dccf3163f75f70bb55686780f1 (patch)
tree770560b54cbf2f3b8ae64aa5f202d25aa6c33c56 /drivers/spi/spi-ti-qspi.c
parent63fad06a2733f78f7565a436a97848aee8099600 (diff)
parent874c571414d5617f4042298986b6a826816ee885 (diff)
Merge tag 'arm-perf-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into next/drivers
Merge "arm-cci PMU updates for 4.1" from Will Deacon: CCI-400 PMU updates This series reworks some of the CCI-400 PMU code so that it can be used on both ARM and ARM64-based systems, without the need to boot in secure mode on the latter. This paves the way for CCI-500 support in future. * tag 'arm-perf-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux: arm-cci: Fix CCI PMU event validation arm-cci: Split the code for PMU vs driver support arm-cci: Get rid of secure transactions for PMU driver arm-cci: Abstract the CCI400 PMU specific definitions arm-cci: Rearrange code for splitting PMU vs driver code drivers: cci: reject groups spanning multiple HW PMUs + Linux 4.0-rc4 Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'drivers/spi/spi-ti-qspi.c')
-rw-r--r--drivers/spi/spi-ti-qspi.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index 884a716e50cb..5c0616870358 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -101,6 +101,7 @@ struct ti_qspi {
#define QSPI_FLEN(n) ((n - 1) << 0)
/* STATUS REGISTER */
+#define BUSY 0x01
#define WC 0x02
/* INTERRUPT REGISTER */
@@ -199,6 +200,21 @@ static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
}
+static inline u32 qspi_is_busy(struct ti_qspi *qspi)
+{
+ u32 stat;
+ unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
+
+ stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
+ while ((stat & BUSY) && time_after(timeout, jiffies)) {
+ cpu_relax();
+ stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
+ }
+
+ WARN(stat & BUSY, "qspi busy\n");
+ return stat & BUSY;
+}
+
static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
{
int wlen, count;
@@ -211,6 +227,9 @@ static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t)
wlen = t->bits_per_word >> 3; /* in bytes */
while (count) {
+ if (qspi_is_busy(qspi))
+ return -EBUSY;
+
switch (wlen) {
case 1:
dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
@@ -266,6 +285,9 @@ static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t)
while (count) {
dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
+ if (qspi_is_busy(qspi))
+ return -EBUSY;
+
ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
if (!wait_for_completion_timeout(&qspi->transfer_complete,
QSPI_COMPLETION_TIMEOUT)) {