[PATCH v2 RESEND] SPI: add CSR SiRFprimaII SPI controller driver

Barry Song 21cnbao at gmail.com
Sun Jan 29 00:29:02 EST 2012


ping...

2011/12/14 Barry Song <Barry.Song at csr.com>:
> From: Zhiwu Song <zhiwu.song at csr.com>
>
> CSR SiRFprimaII has two SPIs (SPI0 and SPI1). Features:
> * Master and slave modes
> * 8-/12-/16-/32-bit data unit
> * 256 bytes receive data FIFO and 256 bytes transmit data FIFO
> * Multi-unit frame
> * Configurable SPI_EN (chip select pin) active state
> * Configurable SPI_CLK polarity
> * Configurable SPI_CLK phase
> * Configurable MSB/LSB first
>
> Signed-off-by: Zhiwu Song <zhiwu.song at csr.com>
> Signed-off-by: Barry Song <Barry.Song at csr.com>
> ---
>  -v2:
>  fix bundle of minor issues Wolfram Sang pointed out;
>  use Wolfram Sang's new devm_request_and_ioremap() api, refer to:
>    https://lkml.org/lkml/2011/10/25/226
>
>  drivers/spi/Kconfig          |    7 +
>  drivers/spi/Makefile         |    1 +
>  drivers/spi/spi-sirf.c       |  627 ++++++++++++++++++++++++++++++++++++++++++
>  include/linux/spi/spi-sirf.h |   27 ++
>  4 files changed, 662 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/spi/spi-sirf.c
>  create mode 100644 include/linux/spi/spi-sirf.h
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index a1fd73d..3dccd54 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -325,6 +325,13 @@ config SPI_SH_SCI
>        help
>          SPI driver for SuperH SCI blocks.
>
> +config SPI_SIRF
> +        tristate "CSR SiRFprimaII SPI controller"
> +       depends on ARCH_PRIMA2
> +       select SPI_BITBANG
> +       help
> +         SPI driver for CSR SiRFprimaII SoCs
> +
>  config SPI_STMP3XXX
>        tristate "Freescale STMP37xx/378x SPI/SSP controller"
>        depends on ARCH_STMP3XXX && SPI_MASTER
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 61c3261..e919846 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -51,6 +51,7 @@ obj-$(CONFIG_SPI_S3C64XX)             += spi-s3c64xx.o
>  obj-$(CONFIG_SPI_SH)                   += spi-sh.o
>  obj-$(CONFIG_SPI_SH_MSIOF)             += spi-sh-msiof.o
>  obj-$(CONFIG_SPI_SH_SCI)               += spi-sh-sci.o
> +obj-$(CONFIG_SPI_SIRF)         += spi-sirf.o
>  obj-$(CONFIG_SPI_STMP3XXX)             += spi-stmp.o
>  obj-$(CONFIG_SPI_TEGRA)                        += spi-tegra.o
>  obj-$(CONFIG_SPI_TI_SSP)               += spi-ti-ssp.o
> diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c
> new file mode 100644
> index 0000000..fc38e97
> --- /dev/null
> +++ b/drivers/spi/spi-sirf.c
> @@ -0,0 +1,627 @@
> +/*
> + * SPI bus driver for CSR SiRFprimaII
> + *
> + * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
> + *
> + * Licensed under GPLv2 or later.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/bitops.h>
> +#include <linux/platform_device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spi/spi_bitbang.h>
> +#include <linux/pinctrl/pinmux.h>
> +#include <linux/spi/spi-sirf.h>
> +
> +#define DRIVER_NAME "sirfsoc_spi"
> +
> +#define SPI_CTRL               0x0000  /* SPI controller configuration register */
> +#define SPI_CMD                        0x0004  /* SPI command register */
> +#define SPI_TX_RX_EN           0x0008  /* SPI interface transfer enable register */
> +#define SPI_INT_EN             0x000C  /* SPI interrupt enable register */
> +#define SPI_INT_STATUS         0x0010  /* SPI interrupt register */
> +#define SPI_TX_DMA_IO_CTRL     0x0100  /* SPI TXFIFO DMA/IO register */
> +#define SPI_TX_DMA_IO_LEN      0x0104  /* SPI transmit data length register */
> +#define SPI_TXFIFO_CTRL                0x0108  /* SPI TXFIFO control register */
> +#define SPI_TXFIFO_LEVEL_CHK   0x010C  /* SPI TXFIFO check level register */
> +#define SPI_TXFIFO_OP          0x0110  /* SPI TXFIFO operation register */
> +#define SPI_TXFIFO_STATUS      0x0114  /* SPI TXFIFO status register */
> +#define SPI_TXFIFO_DATA                0x0118  /* SPI TXFIFO bottom */
> +#define SPI_RX_DMA_IO_CTRL     0x0120  /* SPI RXFIFO DMA/IO register */
> +#define SPI_RX_DMA_IO_LEN      0x0124  /* SPI receive length register */
> +#define SPI_RXFIFO_CTRL                0x0128  /* SPI RXFIFO control register */
> +#define SPI_RXFIFO_LEVEL_CHK   0x012C  /* SPI RXFIFO check level register */
> +#define SPI_RXFIFO_OP          0x0130  /* SPI RXFIFO operation register */
> +#define SPI_RXFIFO_STATUS      0x0134  /* SPI RXFIFO status register */
> +#define SPI_RXFIFO_DATA                0x0138  /* SPI RXFIFO bottom */
> +#define SLV_RX_SAMPLE_MODE     0x0140  /* Rx sample mode when slave mode */
> +#define DUMMY_DELAY_CTRL       0x0144  /* Control reg when insert dummy delay */
> +
> +/* SPI CTRL register defines */
> +#define SLV_MODE               BIT(16)
> +#define CMD_MODE               BIT(17)
> +#define CS_IO_OUT              BIT(18)
> +#define CS_IO_MODE             BIT(19)
> +#define CLK_IDLE_STAT          BIT(20)
> +#define CS_IDLE_STAT           BIT(21)
> +#define TRAN_MSB               BIT(22)
> +#define DRV_POS_EDGE           BIT(23)
> +#define CS_HOLD_TIME           BIT(24)
> +#define CLK_SAMPLE_MODE                BIT(25)
> +#define TRAN_DAT_FORMAT_8      (0 << 26)
> +#define TRAN_DAT_FORMAT_12     (1 << 26)
> +#define TRAN_DAT_FORMAT_16     (2 << 26)
> +#define TRAN_DAT_FORMAT_32     (3 << 26)
> +#define CMD_BYTE_NUM(x)                ((x & 3) << 28)
> +#define ENA_AUTO_CLR           BIT(30)
> +#define MUL_DAT_MODE           BIT(31)
> +
> +/* Interrupt Enable */
> +#define RX_DONE_INT_EN         BIT(0)
> +#define TX_DONE_INT_EN         BIT(1)
> +#define RX_OFLOW_INT_EN                BIT(2)
> +#define TX_UFLOW_INT_EN                BIT(3)
> +#define RX_IO_DMA_INT_EN       BIT(4)
> +#define TX_IO_DMA_INT_EN       BIT(5)
> +#define RXFIFO_FULL_INT_EN     BIT(6)
> +#define TXFIFO_EMPTY_INT_EN    BIT(7)
> +#define RXFIFO_THD_INT_EN      BIT(8)
> +#define TXFIFO_THD_INT_EN      BIT(9)
> +#define FRM_END_INT_EN         BIT(10)
> +
> +#define INT_MASK_ALL           0x1FFF
> +
> +/* Interrupt status */
> +#define RX_DONE                        BIT(0)
> +#define TX_DONE                        BIT(1)
> +#define RX_OFLOW               BIT(2)
> +#define TX_UFLOW               BIT(3)
> +#define DMA_IO_RX_DONE         BIT(4)
> +#define DMA_IO_TX_DONE         BIT(5)
> +#define RXFIFO_FULL            BIT(6)
> +#define TXFIFO_EMPTY           BIT(7)
> +#define RXFIFO_THD_REACH       BIT(8)
> +#define TXFIFO_THD_REACH       BIT(9)
> +#define FRM_END                        BIT(10)
> +
> +/* TX RX enable */
> +#define SPI_RX_EN              BIT(0)
> +#define SPI_TX_EN              BIT(1)
> +#define SPI_CMD_TX_EN          BIT(2)
> +
> +#define IO_MODE_SEL            BIT(0)
> +#define RX_DMA_FLUSH           BIT(2)
> +
> +/* FIFO OPs */
> +#define FIFO_RESET             BIT(0)
> +#define FIFO_START             BIT(1)
> +
> +/* FIFO CTRL */
> +#define FIFO_WIDTH_BYTE                (0 << 0)
> +#define FIFO_WIDTH_WORD                (1 << 0)
> +#define FIFO_WIDTH_DWORD       (2 << 0)
> +
> +/* FIFO Status */
> +#define        FIFO_LEVEL_MASK         0xFF
> +#define FIFO_FULL              BIT(8)
> +#define FIFO_EMPTY             BIT(9)
> +
> +/* 256 bytes rx/tx FIFO */
> +#define FIFO_SIZE              256
> +#define DATA_FRAME_LEN_MAX     (64 * 1024)
> +
> +#define FIFO_SC(x)             ((x) & 0x3F)
> +#define FIFO_LC(x)             (((x) & 0x3F) << 10)
> +#define FIFO_HC(x)             (((x) & 0x3F) << 20)
> +#define FIFO_THD(x)            (((x) & 0xFF) << 2)
> +
> +struct sirfsoc_spi {
> +       struct spi_bitbang bitbang;
> +       struct completion done;
> +
> +       u32 irq;
> +       void __iomem *base;
> +       u32 ctrl_freq;  /* SPI controller clock speed */
> +       struct clk *clk;
> +       int bus_num;
> +       struct pinmux *pmx;
> +
> +       /* rx & tx bufs from the spi_transfer */
> +       const void *tx;
> +       void *rx;
> +
> +       /* place received word into rx buffer */
> +       void (*enq_rx_word) (u32 rx_data, struct sirfsoc_spi *);
> +       /* get word from tx buffer for sending */
> +        u32(*pop_tx_word) (struct sirfsoc_spi *);
> +
> +       /* number of words left to be tranmitted/received */
> +       unsigned int left_tx_cnt;
> +       unsigned int left_rx_cnt;
> +
> +       /* tasklet to push tx msg into FIFO */
> +       struct tasklet_struct tasklet_tx;
> +};
> +
> +static void spi_sirfsoc_rx_buf_u8(u32 data, struct sirfsoc_spi *sspi)
> +{
> +       u8 *rx = sspi->rx;
> +       *rx++ = (u8) data;
> +       sspi->rx = rx;
> +}
> +
> +static u32 spi_sirfsoc_tx_buf_u8(struct sirfsoc_spi *sspi)
> +{
> +       u32 data;
> +       const u8 *tx = sspi->tx;
> +       data = *tx++;
> +       sspi->tx = tx;
> +       return data;
> +}
> +
> +static void spi_sirfsoc_rx_buf_u16(u32 data, struct sirfsoc_spi *sspi)
> +{
> +       u16 *rx = sspi->rx;
> +       *rx++ = (u16) data;
> +       sspi->rx = rx;
> +}
> +
> +static u32 spi_sirfsoc_tx_buf_u16(struct sirfsoc_spi *sspi)
> +{
> +       u32 data;
> +       const u16 *tx = sspi->tx;
> +       data = *tx++;
> +       sspi->tx = tx;
> +       return data;
> +}
> +
> +static void spi_sirfsoc_rx_buf_u32(u32 data, struct sirfsoc_spi *sspi)
> +{
> +       u32 *rx = sspi->rx;
> +       *rx++ = (u32) data;
> +       sspi->rx = rx;
> +}
> +
> +static u32 spi_sirfsoc_tx_buf_u32(struct sirfsoc_spi *sspi)
> +{
> +       u32 data;
> +       const u32 *tx = sspi->tx;
> +       data = *tx++;
> +       sspi->tx = tx;
> +       return data;
> +}
> +
> +static void spi_sirfsoc_tasklet_tx(unsigned long arg)
> +{
> +       struct sirfsoc_spi *sspi = (struct sirfsoc_spi *)arg;
> +       u32 word = 0;
> +
> +       /* Fill Tx FIFO while there are left words to be transmitted */
> +       while (!((readl(sspi->base + SPI_TXFIFO_STATUS) & FIFO_FULL))
> +              && sspi->left_tx_cnt) {
> +               if (sspi->tx)
> +                       word = sspi->pop_tx_word(sspi);
> +               writel(word, sspi->base + SPI_TXFIFO_DATA);
> +               sspi->left_tx_cnt--;
> +       }
> +}
> +
> +static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
> +{
> +       struct sirfsoc_spi *sspi = dev_id;
> +       u32 spi_stat = readl(sspi->base + SPI_INT_STATUS);
> +       u32 word = 0;
> +
> +       writel(spi_stat, sspi->base + SPI_INT_STATUS);
> +
> +       /* Error Conditions */
> +       if (spi_stat & RX_OFLOW || spi_stat & TX_UFLOW) {
> +               complete(&sspi->done);
> +               writel(0x0, sspi->base + SPI_INT_EN);
> +       }
> +
> +       if (spi_stat & FRM_END) {
> +               while (!((readl(sspi->base + SPI_RXFIFO_STATUS)
> +                                       & FIFO_EMPTY)) && sspi->left_rx_cnt) {
> +                       word = readl(sspi->base + SPI_RXFIFO_DATA);
> +                       if (sspi->rx)
> +                               sspi->enq_rx_word(word, sspi);
> +
> +                       sspi->left_rx_cnt--;
> +               }
> +
> +               /* Received all words */
> +               if ((sspi->left_rx_cnt == 0) && (sspi->left_tx_cnt == 0)) {
> +                       complete(&sspi->done);
> +                       writel(0x0, sspi->base + SPI_INT_EN);
> +               }
> +       }
> +
> +       if (spi_stat & RXFIFO_THD_REACH || spi_stat & TXFIFO_THD_REACH ||
> +               spi_stat & RXFIFO_FULL || spi_stat & TXFIFO_EMPTY)
> +               tasklet_schedule(&sspi->tasklet_tx);
> +
> +       return IRQ_HANDLED;
> +}
> +
> +static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
> +{
> +       struct sirfsoc_spi *sspi;
> +       u32 word = 0;
> +       int timeout = t->len * 10;
> +       sspi = spi_master_get_devdata(spi->master);
> +
> +       sspi->tx = t->tx_buf;
> +       sspi->rx = t->rx_buf;
> +       sspi->left_tx_cnt = sspi->left_rx_cnt = t->len;
> +       INIT_COMPLETION(sspi->done);
> +
> +       writel(INT_MASK_ALL, sspi->base + SPI_INT_STATUS);
> +
> +       if (t->len == 1) {
> +               writel(readl(sspi->base + SPI_CTRL) | ENA_AUTO_CLR,
> +                      sspi->base + SPI_CTRL);
> +               writel(0, sspi->base + SPI_TX_DMA_IO_LEN);
> +               writel(0, sspi->base + SPI_RX_DMA_IO_LEN);
> +       } else if ((t->len > 1) && (t->len < DATA_FRAME_LEN_MAX)) {
> +               writel(readl(sspi->base + SPI_CTRL) | MUL_DAT_MODE |
> +                      ENA_AUTO_CLR, sspi->base + SPI_CTRL);
> +               writel(t->len - 1, sspi->base + SPI_TX_DMA_IO_LEN);
> +               writel(t->len - 1, sspi->base + SPI_RX_DMA_IO_LEN);
> +       } else {
> +               writel(readl(sspi->base + SPI_CTRL),
> +                       sspi->base + SPI_CTRL);
> +               writel(0, sspi->base + SPI_TX_DMA_IO_LEN);
> +               writel(0, sspi->base + SPI_RX_DMA_IO_LEN);
> +       }
> +
> +       writel(FIFO_RESET, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_RESET, sspi->base + SPI_TXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_TXFIFO_OP);
> +
> +       /* fill up the Tx FIFO */
> +       while (!(readl(sspi->base + SPI_TXFIFO_STATUS) & FIFO_FULL) &&
> +               (sspi->left_tx_cnt > 0)) {
> +               if (sspi->tx)
> +                       word = sspi->pop_tx_word(sspi);
> +               writel(word, sspi->base + SPI_TXFIFO_DATA);
> +               sspi->left_tx_cnt--;
> +       }
> +       writel(RX_OFLOW_INT_EN | TX_UFLOW_INT_EN | RXFIFO_THD_INT_EN |
> +               TXFIFO_THD_INT_EN | FRM_END_INT_EN | RXFIFO_FULL_INT_EN |
> +               TXFIFO_EMPTY_INT_EN, sspi->base + SPI_INT_EN);
> +       writel(SPI_RX_EN | SPI_TX_EN, sspi->base + SPI_TX_RX_EN);
> +
> +       if (wait_for_completion_timeout(&sspi->done, timeout) == 0)
> +               dev_err(&spi->dev, "transfer timeout\n");
> +
> +       /* TX, RX FIFO stop */
> +       writel(0, sspi->base + SPI_RXFIFO_OP);
> +       writel(0, sspi->base + SPI_TXFIFO_OP);
> +       writel(0, sspi->base + SPI_TX_RX_EN);
> +       writel(0, sspi->base + SPI_INT_EN);
> +
> +       return t->len - sspi->left_rx_cnt;
> +}
> +
> +static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
> +{
> +       struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
> +       struct sirfsoc_spi_ctrldata *ctl_data = spi->controller_data;
> +       u32 regval = readl(sspi->base + SPI_CTRL);
> +
> +       switch (value) {
> +       case BITBANG_CS_ACTIVE:
> +               if (ctl_data->cs_type == CS_HW_CTRL) {
> +                       /*
> +                        * In hardware control mode, CS output is controlled
> +                        * by the CS hardware logic
> +                        */
> +                       regval &= ~CS_IO_OUT;
> +                       if (ctl_data->cs_hold_clk == CS_HOLD_2)
> +                               regval |= CS_HOLD_TIME;
> +               } else if (ctl_data->cs_type == CS_RISC_IO) {
> +                       /*
> +                        * In I/O mode, CS outputs the value of the CS_IO_OUT bit
> +                        */
> +                       regval |= CS_IO_OUT;
> +                       if (spi->mode & SPI_CS_HIGH)
> +                               regval |= CS_IO_OUT;
> +               } else if (ctl_data->cs_type == CS_GPIO)
> +                       ctl_data->chip_select();
> +               break;
> +       case BITBANG_CS_INACTIVE:
> +               if (ctl_data->cs_type == CS_RISC_IO) {
> +                       if (spi->mode & SPI_CS_HIGH)
> +                               regval &= ~CS_IO_OUT;
> +                       else
> +                               regval |= CS_IO_OUT;
> +               } else if (ctl_data->cs_type == CS_GPIO)
> +                       ctl_data->chip_deselect();
> +               break;
> +       }
> +       writel(regval, sspi->base + SPI_CTRL);
> +}
> +
> +static int
> +spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
> +{
> +       struct sirfsoc_spi *sspi;
> +       u8 bits_per_word = 0;
> +       int hz = 0;
> +       u32 regval;
> +       u32 txfifo_ctrl, rxfifo_ctrl;
> +       u32 fifo_size = FIFO_SIZE / 4;
> +
> +       sspi = spi_master_get_devdata(spi->master);
> +
> +       bits_per_word = t && t->bits_per_word ? t->bits_per_word :
> +               spi->bits_per_word;
> +       hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
> +
> +       /* Enable IO mode for RX, TX */
> +       writel(IO_MODE_SEL, sspi->base + SPI_TX_DMA_IO_CTRL);
> +       writel(IO_MODE_SEL, sspi->base + SPI_RX_DMA_IO_CTRL);
> +       regval = (sspi->ctrl_freq / (2 * hz)) - 1;
> +
> +       if (regval > 0xFFFF || regval < 0) {
> +               dev_err(&spi->dev, "Speed %d not supported\n", hz);
> +               return -EINVAL;
> +       }
> +
> +       switch (bits_per_word) {
> +       case 8:
> +               regval |= TRAN_DAT_FORMAT_8;
> +               sspi->enq_rx_word = spi_sirfsoc_rx_buf_u8;
> +               sspi->pop_tx_word = spi_sirfsoc_tx_buf_u8;
> +               txfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_BYTE;
> +               rxfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_BYTE;
> +               break;
> +       case 12:
> +       case 16:
> +               regval |= (bits_per_word ==  12) ? TRAN_DAT_FORMAT_12 :
> +                       TRAN_DAT_FORMAT_16;
> +               sspi->enq_rx_word = spi_sirfsoc_rx_buf_u16;
> +               sspi->pop_tx_word = spi_sirfsoc_tx_buf_u16;
> +               txfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_WORD;
> +               rxfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_WORD;
> +               break;
> +       case 32:
> +               regval |= TRAN_DAT_FORMAT_32;
> +               sspi->enq_rx_word = spi_sirfsoc_rx_buf_u32;
> +               sspi->pop_tx_word = spi_sirfsoc_tx_buf_u32;
> +               txfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_DWORD;
> +               rxfifo_ctrl = FIFO_THD(FIFO_SIZE / 2) | FIFO_WIDTH_DWORD;
> +               break;
> +       default:
> +               dev_err(&spi->dev, "Bits per word %d not supported\n",
> +                      bits_per_word);
> +               return -EINVAL;
> +       }
> +
> +       if (!(spi->mode & SPI_CS_HIGH))
> +               regval |= CS_IDLE_STAT;
> +       if (!(spi->mode & SPI_LSB_FIRST))
> +               regval |= TRAN_MSB;
> +       if (spi->mode & SPI_CPOL)
> +               regval |= CLK_IDLE_STAT;
> +
> +       /*
> +        * Data should be driven at least 1/2 cycle before the fetch edge to make
> +        * sure that data gets stable at the fetch edge.
> +        */
> +       if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
> +           (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
> +               regval &= ~DRV_POS_EDGE;
> +       else
> +               regval |= DRV_POS_EDGE;
> +
> +       writel(FIFO_SC(fifo_size - 2) | FIFO_LC(fifo_size / 2) | FIFO_HC(2),
> +              sspi->base + SPI_TXFIFO_LEVEL_CHK);
> +       writel(FIFO_SC(2) | FIFO_LC(fifo_size / 2) | FIFO_HC(fifo_size - 2),
> +              sspi->base + SPI_RXFIFO_LEVEL_CHK);
> +       writel(txfifo_ctrl, sspi->base + SPI_TXFIFO_CTRL);
> +       writel(rxfifo_ctrl, sspi->base + SPI_RXFIFO_CTRL);
> +
> +       writel(regval, sspi->base + SPI_CTRL);
> +       return 0;
> +}
> +
> +static int spi_sirfsoc_setup(struct spi_device *spi)
> +{
> +       struct spi_bitbang *bitbang;
> +       struct sirfsoc_spi *sspi;
> +
> +       if (!spi->max_speed_hz)
> +               return -EINVAL;
> +
> +       sspi = spi_master_get_devdata(spi->master);
> +       bitbang = &sspi->bitbang;
> +
> +       if (!spi->bits_per_word)
> +               spi->bits_per_word = 8;
> +
> +       return spi_sirfsoc_setup_transfer(spi, NULL);
> +}
> +
> +static int __devinit spi_sirfsoc_probe(struct platform_device *dev)
> +{
> +       struct sirfsoc_spi *sspi;
> +       struct spi_master *master;
> +       struct resource *mem_res;
> +       int ret;
> +
> +       master = spi_alloc_master(&dev->dev, sizeof(*sspi));
> +       if (master == NULL) {
> +               dev_err(&dev->dev, "Unable to allocate SPI master\n");
> +               return -ENOMEM;
> +       }
> +       platform_set_drvdata(dev, master);
> +       sspi = spi_master_get_devdata(master);
> +
> +       mem_res = platform_get_resource(dev, IORESOURCE_MEM, 0);
> +       if (mem_res == NULL) {
> +               dev_err(&dev->dev, "Unable to get IO resource\n");
> +               ret = -ENOMEM;
> +               goto free_master;
> +       }
> +
> +       sspi->base = devm_request_and_ioremap(&dev->dev, mem_res);
> +       if (sspi->base == NULL) {
> +               dev_err(&dev->dev, "IO remap failed!\n");
> +               ret = -ENOMEM;
> +               goto free_master;
> +       }
> +
> +       if (of_property_read_u32(dev->dev.of_node, "cell-index", &dev->id)) {
> +               dev_err(&dev->dev, "Fail to get index\n");
> +               ret = -ENODEV;
> +               goto free_master;
> +       }
> +
> +       sspi->irq = platform_get_irq(dev, 0);
> +       if (sspi->irq < 0) {
> +               ret = -ENODEV;
> +               goto free_master;
> +       }
> +       ret = devm_request_irq(&dev->dev, sspi->irq, spi_sirfsoc_irq, 0, DRIVER_NAME, sspi);
> +       if (ret)
> +               goto free_master;
> +
> +       sspi->bitbang.master = spi_master_get(master);
> +       sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
> +       sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
> +       sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
> +       sspi->bitbang.master->setup = spi_sirfsoc_setup;
> +       sspi->bitbang.master->num_chipselect = 0xFFFF;
> +       master->bus_num = dev->id;
> +       sspi->bitbang.master->dev.of_node = dev->dev.of_node;
> +
> +       sspi->pmx = pinmux_get(&dev->dev, NULL);
> +       ret = IS_ERR(sspi->pmx);
> +       if (ret)
> +               goto free_master;
> +
> +       pinmux_enable(sspi->pmx);
> +
> +       sspi->clk = clk_get(&dev->dev, NULL);
> +       if (IS_ERR(sspi->clk)) {
> +               ret = -EINVAL;
> +               goto free_pmx;
> +       }
> +       clk_enable(sspi->clk);
> +       sspi->ctrl_freq = clk_get_rate(sspi->clk);
> +
> +       init_completion(&sspi->done);
> +
> +       tasklet_init(&sspi->tasklet_tx, spi_sirfsoc_tasklet_tx,
> +                    (unsigned long)sspi);
> +
> +       writel(FIFO_RESET, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_RESET, sspi->base + SPI_TXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_TXFIFO_OP);
> +       writel(0, sspi->base + DUMMY_DELAY_CTRL);       /* We are not using dummy delay between command and data */
> +
> +       ret = spi_bitbang_start(&sspi->bitbang);
> +       if (ret != 0)
> +               goto free_clk;
> +
> +       dev_info(&dev->dev, "registerred, bus number = %d\n", master->bus_num);
> +
> +       return 0;
> +
> +free_clk:
> +       clk_disable(sspi->clk);
> +       clk_put(sspi->clk);
> +free_pmx:
> +       pinmux_disable(sspi->pmx);
> +       pinmux_put(sspi->pmx);
> +free_master:
> +       spi_master_put(master);
> +
> +       return ret;
> +}
> +
> +static int  __devexit spi_sirfsoc_remove(struct platform_device *dev)
> +{
> +       struct spi_master *master;
> +       struct sirfsoc_spi *sspi;
> +
> +       master = platform_get_drvdata(dev);
> +       sspi = spi_master_get_devdata(master);
> +
> +       spi_bitbang_stop(&sspi->bitbang);
> +       clk_disable(sspi->clk);
> +       clk_put(sspi->clk);
> +       pinmux_disable(sspi->pmx);
> +       pinmux_put(sspi->pmx);
> +       spi_master_put(master);
> +       return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int spi_sirfsoc_suspend(struct device *dev)
> +{
> +       struct platform_device *pdev = to_platform_device(dev);
> +       struct spi_master *master = platform_get_drvdata(pdev);
> +       struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
> +
> +       clk_disable(sspi->clk);
> +       return 0;
> +}
> +
> +static int spi_sirfsoc_resume(struct device *dev)
> +{
> +       struct platform_device *pdev = to_platform_device(dev);
> +       struct spi_master *master = platform_get_drvdata(pdev);
> +       struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
> +
> +       clk_enable(sspi->clk);
> +       writel(FIFO_RESET, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_RESET, sspi->base + SPI_TXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_RXFIFO_OP);
> +       writel(FIFO_START, sspi->base + SPI_TXFIFO_OP);
> +
> +       return 0;
> +}
> +
> +static const struct dev_pm_ops spi_sirfsoc_pm_ops = {
> +       .suspend = spi_sirfsoc_suspend,
> +       .resume = spi_sirfsoc_resume,
> +};
> +#endif
> +
> +static const struct of_device_id spi_sirfsoc_of_match[] = {
> +       { .compatible = "sirf,prima2-spi", },
> +       {}
> +};
> +MODULE_DEVICE_TABLE(of, sirfsoc_spi_of_match);
> +
> +static struct platform_driver spi_sirfsoc_driver = {
> +       .driver = {
> +               .name = DRIVER_NAME,
> +               .owner = THIS_MODULE,
> +#ifdef CONFIG_PM
> +               .pm     = &spi_sirfsoc_pm_ops,
> +#endif
> +               .of_match_table = spi_sirfsoc_of_match,
> +       },
> +       .probe = spi_sirfsoc_probe,
> +       .remove = __devexit_p(spi_sirfsoc_remove),
> +};
> +module_platform_driver(spi_sirfsoc_driver);
> +
> +MODULE_DESCRIPTION("SiRF SoC SPI master driver");
> +MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song at csr.com>, "
> +               "Barry Song <Baohua.Song at csr.com>");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/spi/spi-sirf.h b/include/linux/spi/spi-sirf.h
> new file mode 100644
> index 0000000..0e647b0
> --- /dev/null
> +++ b/include/linux/spi/spi-sirf.h
> @@ -0,0 +1,27 @@
> +/*
> + * include/linux/spi/spi_sirfsoc.h
> + *
> + * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
> + *
> + * Licensed under GPLv2 or later.
> + */
> +
> +#ifndef __SIRFSOC_SPI_H__
> +#define __SIRFSOC_SPI_H__
> +
> +struct sirfsoc_spi_ctrldata {
> +       int cs_type;
> +       void (*chip_select) (void);
> +       void (*chip_deselect) (void);
> +       int cs_hold_clk;
> +};
> +
> +#define CS_HW_CTRL     1
> +#define CS_RISC_IO     2
> +#define CS_GPIO                3
> +#define CS_SW_CTRL     4
> +
> +#define CS_HOLD_1      0
> +#define CS_HOLD_2      1
> +
> +#endif
> --
> 1.7.1



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