static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
struct spi_imx_config *config)
{
u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0;
u32 clk = config->speed_hz, delay;
/*
* The hardware seems to have a race condition when changing modes. The
* current assumption is that the selection of the channel arrives
* earlier in the hardware than the mode bits when they are written at
* the same time.
* So set master mode for all channels as we do not support slave mode.
*/
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
/* set clock speed */
ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz, &clk);
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
if (config->mode & SPI_CPHA)
cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
if (config->mode & SPI_CPOL) {
cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
}
if (config->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
/*
* Wait until the changes in the configuration register CONFIGREG
* propagate into the hardware. It takes exactly one tick of the
* SCLK clock, but we will wait two SCLK clock just to be sure. The
* effect of the delay it takes for the hardware to apply changes
* is noticable if the SCLK clock run very slow. In such a case, if
* the polarity of SCLK should be inverted, the GPIO ChipSelect might
* be asserted before the SCLK polarity changes, which would disrupt
* the SPI communication as the device on the other end would consider
* the change of SCLK polarity as a clock tick already.
*/
delay = (2 * 1000000) / clk;
if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
udelay(delay);
else /* SCLK is _very_ slow */
usleep_range(delay, delay + 10);
return 0;
}
static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
struct spi_imx_config *config)
{
u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0;
/*
* The hardware seems to have a race condition when changing modes. The
* current assumption is that the selection of the channel arrives
* earlier in the hardware than the mode bits when they are written at
* the same time.
* So set master mode for all channels as we do not support slave mode.
*/
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
/* set clock speed */
ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz);
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
if (config->mode & SPI_CPHA)
cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
if (config->mode & SPI_CPOL) {
cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
}
if (config->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
return 0;
}
static int mx51_ecspi_config(struct spi_device *spi,
struct spi_imx_config *config)
{
struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
u32 clk = config->speed_hz, delay, reg;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
/*
* The hardware seems to have a race condition when changing modes. The
* current assumption is that the selection of the channel arrives
* earlier in the hardware than the mode bits when they are written at
* the same time.
* So set master mode for all channels as we do not support slave mode.
*/
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
/* set clock speed */
ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
spi_imx->spi_bus_clk = clk;
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
if (spi->mode & SPI_CPHA)
cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
else
cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
if (spi->mode & SPI_CPOL) {
cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
} else {
cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
}
if (spi->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
else
cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
if (spi_imx->usedma)
ctrl |= MX51_ECSPI_CTRL_SMC;
/* CTRL register always go first to bring out controller from reset */
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
if (spi->mode & SPI_LOOP)
reg |= MX51_ECSPI_TESTREG_LBC;
else
reg &= ~MX51_ECSPI_TESTREG_LBC;
writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
/*
* Wait until the changes in the configuration register CONFIGREG
* propagate into the hardware. It takes exactly one tick of the
* SCLK clock, but we will wait two SCLK clock just to be sure. The
* effect of the delay it takes for the hardware to apply changes
* is noticable if the SCLK clock run very slow. In such a case, if
* the polarity of SCLK should be inverted, the GPIO ChipSelect might
* be asserted before the SCLK polarity changes, which would disrupt
* the SPI communication as the device on the other end would consider
* the change of SCLK polarity as a clock tick already.
*/
delay = (2 * 1000000) / clk;
if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
udelay(delay);
else /* SCLK is _very_ slow */
usleep_range(delay, delay + 10);
/*
* Configure the DMA register: setup the watermark
* and enable DMA request.
*/
writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
return 0;
}