From 1e970c7d97f61a78657a6d751da7687a3ed2bbc6 Mon Sep 17 00:00:00 2001 From: Kevin Wells Date: Thu, 2 Sep 2010 10:03:12 -0700 Subject: [PATCH 39/52] amba_pl022: Setup SPI configuration based on spi->mode This patch changes the way SPI transfers are setup. The previous method uses the pl022_config_chip data for configuration of loopback mode, edge count, clock polarity, number of data bits, and bit transfer order. This change configures these parameters based on spi->mode passed via master->setup and will allow the drivers use SPI to configure the interface. The fields lbm, clk_phase, clk_pol, and data_size are no longer needed. For the ST/pl023 setup, the first bit transferred for both RX and TX is now selected with the SPI_LSB_FIRST flag in spi->mode. There are also several very minor cleanups in the patch that fix return status on setup failures. This has been tested with the AT25 serial EEPROM driver and spidev modes 0-3 with loopback and varying data sizes. Reported-by: Quentin Yang Signed-off-by: Kevin Wells --- drivers/spi/amba-pl022.c | 121 ++++++++++++++++++++-------------------------- 1 files changed, 53 insertions(+), 68 deletions(-) diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c index 4c37c4e..4c7d174 100644 --- a/drivers/spi/amba-pl022.c +++ b/drivers/spi/amba-pl022.c @@ -1250,12 +1250,6 @@ static int destroy_queue(struct pl022 *pl022) static int verify_controller_parameters(struct pl022 *pl022, struct pl022_config_chip *chip_info) { - if ((chip_info->lbm != LOOPBACK_ENABLED) - && (chip_info->lbm != LOOPBACK_DISABLED)) { - dev_err(chip_info->dev, - "loopback Mode is configured incorrectly\n"); - return -EINVAL; - } if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI) || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) { dev_err(chip_info->dev, @@ -1281,24 +1275,6 @@ static int verify_controller_parameters(struct pl022 *pl022, "cpsdvsr is configured incorrectly\n"); return -EINVAL; } - if ((chip_info->endian_rx != SSP_RX_MSB) - && (chip_info->endian_rx != SSP_RX_LSB)) { - dev_err(chip_info->dev, - "RX FIFO endianess is configured incorrectly\n"); - return -EINVAL; - } - if ((chip_info->endian_tx != SSP_TX_MSB) - && (chip_info->endian_tx != SSP_TX_LSB)) { - dev_err(chip_info->dev, - "TX FIFO endianess is configured incorrectly\n"); - return -EINVAL; - } - if ((chip_info->data_size < SSP_DATA_BITS_4) - || (chip_info->data_size > SSP_DATA_BITS_32)) { - dev_err(chip_info->dev, - "DATA Size is configured incorrectly\n"); - return -EINVAL; - } if ((chip_info->com_mode != INTERRUPT_TRANSFER) && (chip_info->com_mode != DMA_TRANSFER) && (chip_info->com_mode != POLLING_TRANSFER)) { @@ -1318,20 +1294,6 @@ static int verify_controller_parameters(struct pl022 *pl022, "TX FIFO Trigger Level is configured incorrectly\n"); return -EINVAL; } - if (chip_info->iface == SSP_INTERFACE_MOTOROLA_SPI) { - if ((chip_info->clk_phase != SSP_CLK_FIRST_EDGE) - && (chip_info->clk_phase != SSP_CLK_SECOND_EDGE)) { - dev_err(chip_info->dev, - "Clock Phase is configured incorrectly\n"); - return -EINVAL; - } - if ((chip_info->clk_pol != SSP_CLK_POL_IDLE_LOW) - && (chip_info->clk_pol != SSP_CLK_POL_IDLE_HIGH)) { - dev_err(chip_info->dev, - "Clock Polarity is configured incorrectly\n"); - return -EINVAL; - } - } if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) { if ((chip_info->ctrl_len < SSP_BITS_4) || (chip_info->ctrl_len > SSP_BITS_32)) { @@ -1496,23 +1458,14 @@ static int process_dma_info(struct pl022_config_chip *chip_info, * controller hardware here, that is not done until the actual transfer * commence. */ - -/* FIXME: JUST GUESSING the spi->mode bits understood by this driver */ -#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ - | SPI_LSB_FIRST | SPI_LOOP) - static int pl022_setup(struct spi_device *spi) { struct pl022_config_chip *chip_info; struct chip_data *chip; int status = 0; struct pl022 *pl022 = spi_master_get_devdata(spi->master); - - if (spi->mode & ~MODEBITS) { - dev_dbg(&spi->dev, "unsupported mode bits %x\n", - spi->mode & ~MODEBITS); - return -EINVAL; - } + unsigned int bits = spi->bits_per_word; + u32 tmp; if (!spi->max_speed_hz) return -EINVAL; @@ -1557,18 +1510,12 @@ static int pl022_setup(struct spi_device *spi) * Set controller data default values: * Polling is supported by default */ - chip_info->lbm = LOOPBACK_DISABLED; chip_info->com_mode = POLLING_TRANSFER; chip_info->iface = SSP_INTERFACE_MOTOROLA_SPI; chip_info->hierarchy = SSP_SLAVE; chip_info->slave_tx_disable = DO_NOT_DRIVE_TX; - chip_info->endian_tx = SSP_TX_LSB; - chip_info->endian_rx = SSP_RX_LSB; - chip_info->data_size = SSP_DATA_BITS_12; chip_info->rx_lev_trig = SSP_RX_1_OR_MORE_ELEM; chip_info->tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC; - chip_info->clk_phase = SSP_CLK_SECOND_EDGE; - chip_info->clk_pol = SSP_CLK_POL_IDLE_LOW; chip_info->ctrl_len = SSP_BITS_8; chip_info->wait_state = SSP_MWIRE_WAIT_ZERO; chip_info->duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX; @@ -1603,12 +1550,16 @@ static int pl022_setup(struct spi_device *spi) chip->xfer_type = chip_info->com_mode; chip->cs_control = chip_info->cs_control; - if (chip_info->data_size <= 8) { - dev_dbg(&spi->dev, "1 <= n <=8 bits per word\n"); + if (bits <= 3) { + /* PL022 doesn't support less than 4-bits */ + status = -ENOTSUPP; + goto err_config_params; + } else if (bits <= 8) { + dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n"); chip->n_bytes = 1; chip->read = READING_U8; chip->write = WRITING_U8; - } else if (chip_info->data_size <= 16) { + } else if (bits <= 16) { dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n"); chip->n_bytes = 2; chip->read = READING_U16; @@ -1625,6 +1576,7 @@ static int pl022_setup(struct spi_device *spi) dev_err(&spi->dev, "a standard pl022 can only handle " "1 <= n <= 16 bit words\n"); + status = -ENOTSUPP; goto err_config_params; } } @@ -1658,6 +1610,8 @@ static int pl022_setup(struct spi_device *spi) /* Special setup for the ST micro extended control registers */ if (pl022->vendor->extended_cr) { + u32 etx; + if (pl022->vendor->pl023) { /* These bits are only in the PL023 */ SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay, @@ -1673,29 +1627,51 @@ static int pl022_setup(struct spi_device *spi) SSP_WRITE_BITS(chip->cr1, chip_info->wait_state, SSP_CR1_MASK_MWAIT_ST, 6); } - SSP_WRITE_BITS(chip->cr0, chip_info->data_size, + SSP_WRITE_BITS(chip->cr0, bits - 1, SSP_CR0_MASK_DSS_ST, 0); - SSP_WRITE_BITS(chip->cr1, chip_info->endian_rx, - SSP_CR1_MASK_RENDN_ST, 4); - SSP_WRITE_BITS(chip->cr1, chip_info->endian_tx, - SSP_CR1_MASK_TENDN_ST, 5); + + if (spi->mode & SPI_LSB_FIRST) { + tmp = SSP_RX_LSB; + etx = SSP_TX_LSB; + } else { + tmp = SSP_RX_MSB; + etx = SSP_TX_MSB; + } + SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4); + SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5); SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig, SSP_CR1_MASK_RXIFLSEL_ST, 7); SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig, SSP_CR1_MASK_TXIFLSEL_ST, 10); } else { - SSP_WRITE_BITS(chip->cr0, chip_info->data_size, + SSP_WRITE_BITS(chip->cr0, bits - 1, SSP_CR0_MASK_DSS, 0); SSP_WRITE_BITS(chip->cr0, chip_info->iface, SSP_CR0_MASK_FRF, 4); } + /* Stuff that is common for all versions */ - SSP_WRITE_BITS(chip->cr0, chip_info->clk_pol, SSP_CR0_MASK_SPO, 6); - SSP_WRITE_BITS(chip->cr0, chip_info->clk_phase, SSP_CR0_MASK_SPH, 7); + if (spi->mode & SPI_CPOL) + tmp = SSP_CLK_POL_IDLE_HIGH; + else + tmp = SSP_CLK_POL_IDLE_LOW; + SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6); + + if (spi->mode & SPI_CPHA) + tmp = SSP_CLK_SECOND_EDGE; + else + tmp = SSP_CLK_FIRST_EDGE; + SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 6); + SSP_WRITE_BITS(chip->cr0, chip_info->clk_freq.scr, SSP_CR0_MASK_SCR, 8); /* Loopback is available on all versions except PL023 */ - if (!pl022->vendor->pl023) - SSP_WRITE_BITS(chip->cr1, chip_info->lbm, SSP_CR1_MASK_LBM, 0); + if (!pl022->vendor->pl023) { + if (spi->mode & SPI_LOOP) + tmp = LOOPBACK_ENABLED; + else + tmp = LOOPBACK_DISABLED; + SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0); + } SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1); SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2); SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD, 3); @@ -1704,6 +1680,7 @@ static int pl022_setup(struct spi_device *spi) spi_set_ctldata(spi, chip); return status; err_config_params: + spi_set_ctldata(spi, NULL); err_first_setup: kfree(chip); return status; @@ -1766,6 +1743,14 @@ pl022_probe(struct amba_device *adev, struct amba_id *id) master->setup = pl022_setup; master->transfer = pl022_transfer; + /* + * Supports mode 0-3, loopback, and active low CS. Transfers are + * always MS bit first on the original pl022. + */ + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; + if (pl022->vendor->extended_cr) + master->mode_bits |= SPI_LSB_FIRST; + dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num); status = amba_request_regions(adev, NULL); -- 1.6.3.3