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| author | Simon Glass <sjg@chromium.org> | 2015-06-05 14:39:33 -0600 |
|---|---|---|
| committer | Tom Warren <twarren@nvidia.com> | 2015-06-09 09:56:13 -0700 |
| commit | 635c2515c398241f59c5936213308ce9709fc475 (patch) | |
| tree | 1884ffbf8d2c6639e1c509e0e345a678c0007c1f /drivers | |
| parent | bbe0d4db53e30affae1194882075e1e0997c4c5c (diff) | |
| download | u-boot-imx-635c2515c398241f59c5936213308ce9709fc475.zip u-boot-imx-635c2515c398241f59c5936213308ce9709fc475.tar.gz u-boot-imx-635c2515c398241f59c5936213308ce9709fc475.tar.bz2 | |
tegra: spi: Drop the claim_bus() method to correct delays
At present the driver does not properly honour the requested SPI CS
deactivation delay since the SPI bus is changed in the claim_bus() method.
Everything the claim_bus() method does can be done when the device is probed
(setting the speed and mode) and at the start of a new transfer (where the
fifo_status is already cleared). So drop this method.
Also, until the delay is complete, we should not touch the bus, so make sure
that spi_cs_activate() is called before other things are done in the xfer()
method.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/spi/tegra114_spi.c | 26 |
1 files changed, 9 insertions, 17 deletions
diff --git a/drivers/spi/tegra114_spi.c b/drivers/spi/tegra114_spi.c index 4bec663..0d69376 100644 --- a/drivers/spi/tegra114_spi.c +++ b/drivers/spi/tegra114_spi.c @@ -143,24 +143,18 @@ static int tegra114_spi_probe(struct udevice *bus) { struct tegra_spi_platdata *plat = dev_get_platdata(bus); struct tegra114_spi_priv *priv = dev_get_priv(bus); + struct spi_regs *regs; priv->regs = (struct spi_regs *)plat->base; + regs = priv->regs; priv->last_transaction_us = timer_get_us(); priv->freq = plat->frequency; priv->periph_id = plat->periph_id; - return 0; -} - -static int tegra114_spi_claim_bus(struct udevice *dev) -{ - struct udevice *bus = dev->parent; - struct tegra114_spi_priv *priv = dev_get_priv(bus); - struct spi_regs *regs = priv->regs; - /* Change SPI clock to correct frequency, PLLP_OUT0 source */ - clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH, priv->freq); + clock_start_periph_pll(priv->periph_id, CLOCK_ID_PERIPH, + priv->freq); /* Clear stale status here */ setbits_le32(®s->fifo_status, @@ -175,9 +169,8 @@ static int tegra114_spi_claim_bus(struct udevice *dev) SPI_FIFO_STS_RX_FIFO_EMPTY); debug("%s: FIFO STATUS = %08x\n", __func__, readl(®s->fifo_status)); - /* Set master mode and sw controlled CS */ - setbits_le32(®s->command1, SPI_CMD1_M_S | SPI_CMD1_CS_SW_HW | - (priv->mode << SPI_CMD1_MODE_SHIFT)); + setbits_le32(&priv->regs->command1, SPI_CMD1_M_S | SPI_CMD1_CS_SW_HW | + (priv->mode << SPI_CMD1_MODE_SHIFT) | SPI_CMD1_CS_SW_VAL); debug("%s: COMMAND1 = %08x\n", __func__, readl(®s->command1)); return 0; @@ -249,6 +242,9 @@ static int tegra114_spi_xfer(struct udevice *dev, unsigned int bitlen, ret = 0; + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(dev); + /* clear all error status bits */ reg = readl(®s->fifo_status); writel(reg, ®s->fifo_status); @@ -260,9 +256,6 @@ static int tegra114_spi_xfer(struct udevice *dev, unsigned int bitlen, /* set xfer size to 1 block (32 bits) */ writel(0, ®s->dma_blk); - if (flags & SPI_XFER_BEGIN) - spi_cs_activate(dev); - /* handle data in 32-bit chunks */ while (num_bytes > 0) { int bytes; @@ -385,7 +378,6 @@ static int tegra114_spi_set_mode(struct udevice *bus, uint mode) } static const struct dm_spi_ops tegra114_spi_ops = { - .claim_bus = tegra114_spi_claim_bus, .xfer = tegra114_spi_xfer, .set_speed = tegra114_spi_set_speed, .set_mode = tegra114_spi_set_mode, |