Commit 87cbfd06 authored by Max Filippov's avatar Max Filippov Committed by John W. Linville
Browse files

p54spi: get rid of busy-wait loops



p54spi_wakeup and p54spi_tx_frame used busy-waiting loop
to poll for 'ready' bits in SPI_ADRS_HOST_INTERRUPTS register.
With this change in place 'WR_READY timeout' messages do not
show anymore.
Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
Acked-by: default avatarChristian Lamparter <chunkeey@web.de>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 6a362bb1
......@@ -167,14 +167,13 @@ static const struct p54spi_spi_reg p54spi_registers_array[] =
static int p54spi_wait_bit(struct p54s_priv *priv, u16 reg, __le32 bits)
{
int i;
__le32 buffer;
for (i = 0; i < 2000; i++) {
p54spi_spi_read(priv, reg, &buffer, sizeof(buffer));
__le32 buffer = p54spi_read32(priv, reg);
if ((buffer & bits) == bits)
return 1;
msleep(1);
msleep(0);
}
return 0;
}
......@@ -185,10 +184,10 @@ static int p54spi_spi_write_dma(struct p54s_priv *priv, __le32 base,
p54spi_write16(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le16(SPI_DMA_WRITE_CTRL_ENABLE));
if (p54spi_wait_bit(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le32(HOST_ALLOWED)) == 0) {
if (!p54spi_wait_bit(priv, SPI_ADRS_DMA_WRITE_CTRL,
cpu_to_le32(HOST_ALLOWED))) {
dev_err(&priv->spi->dev, "spi_write_dma not allowed "
"to DMA write.");
"to DMA write.\n");
return -EAGAIN;
}
......@@ -330,21 +329,15 @@ static inline void p54spi_int_ack(struct p54s_priv *priv, u32 val)
static void p54spi_wakeup(struct p54s_priv *priv)
{
unsigned long timeout;
u32 ints;
/* wake the chip */
p54spi_write32(priv, SPI_ADRS_ARM_INTERRUPTS,
cpu_to_le32(SPI_TARGET_INT_WAKEUP));
/* And wait for the READY interrupt */
timeout = jiffies + HZ;
ints = p54spi_read32(priv, SPI_ADRS_HOST_INTERRUPTS);
while (!(ints & SPI_HOST_INT_READY)) {
if (time_after(jiffies, timeout))
goto out;
ints = p54spi_read32(priv, SPI_ADRS_HOST_INTERRUPTS);
if (!p54spi_wait_bit(priv, SPI_ADRS_HOST_INTERRUPTS,
cpu_to_le32(SPI_HOST_INT_READY))) {
dev_err(&priv->spi->dev, "INT_READY timeout\n");
goto out;
}
p54spi_int_ack(priv, SPI_HOST_INT_READY);
......@@ -432,9 +425,7 @@ static irqreturn_t p54spi_interrupt(int irq, void *config)
static int p54spi_tx_frame(struct p54s_priv *priv, struct sk_buff *skb)
{
struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
unsigned long timeout;
int ret = 0;
u32 ints;
p54spi_wakeup(priv);
......@@ -442,15 +433,11 @@ static int p54spi_tx_frame(struct p54s_priv *priv, struct sk_buff *skb)
if (ret < 0)
goto out;
timeout = jiffies + 2 * HZ;
ints = p54spi_read32(priv, SPI_ADRS_HOST_INTERRUPTS);
while (!(ints & SPI_HOST_INT_WR_READY)) {
if (time_after(jiffies, timeout)) {
dev_err(&priv->spi->dev, "WR_READY timeout\n");
ret = -1;
goto out;
}
ints = p54spi_read32(priv, SPI_ADRS_HOST_INTERRUPTS);
if (!p54spi_wait_bit(priv, SPI_ADRS_HOST_INTERRUPTS,
cpu_to_le32(SPI_HOST_INT_WR_READY))) {
dev_err(&priv->spi->dev, "WR_READY timeout\n");
ret = -1;
goto out;
}
p54spi_int_ack(priv, SPI_HOST_INT_WR_READY);
......
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