/* * Copyright (C) 2009 Texas Instruments. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/gpio.h> #include <linux/module.h> #include <linux/delay.h> #include <linux/platform_device.h> #include <linux/err.h> #include <linux/clk.h> #include <linux/dma-mapping.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> #include <linux/slab.h> #include <mach/spi.h> #include <mach/edma.h> #define SPI_NO_RESOURCE ((resource_size_t)-1) #define SPI_MAX_CHIPSELECT 2 #define CS_DEFAULT 0xFF #define SPI_BUFSIZ (SMP_CACHE_BYTES + 1) #define DAVINCI_DMA_DATA_TYPE_S8 0x01 #define DAVINCI_DMA_DATA_TYPE_S16 0x02 #define DAVINCI_DMA_DATA_TYPE_S32 0x04 #define SPIFMT_PHASE_MASK BIT(16) #define SPIFMT_POLARITY_MASK BIT(17) #define SPIFMT_DISTIMER_MASK BIT(18) #define SPIFMT_SHIFTDIR_MASK BIT(20) #define SPIFMT_WAITENA_MASK BIT(21) #define SPIFMT_PARITYENA_MASK BIT(22) #define SPIFMT_ODD_PARITY_MASK BIT(23) #define SPIFMT_WDELAY_MASK 0x3f000000u #define SPIFMT_WDELAY_SHIFT 24 #define SPIFMT_CHARLEN_MASK 0x0000001Fu /* SPIGCR1 */ #define SPIGCR1_SPIENA_MASK 0x01000000u /* SPIPC0 */ #define SPIPC0_DIFUN_MASK BIT(11) /* MISO */ #define SPIPC0_DOFUN_MASK BIT(10) /* MOSI */ #define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */ #define SPIPC0_SPIENA_MASK BIT(8) /* nREADY */ #define SPIPC0_EN1FUN_MASK BIT(1) #define SPIPC0_EN0FUN_MASK BIT(0) #define SPIINT_MASKALL 0x0101035F #define SPI_INTLVL_1 0x000001FFu #define SPI_INTLVL_0 0x00000000u /* SPIDAT1 */ #define SPIDAT1_CSHOLD_SHIFT 28 #define SPIDAT1_CSNR_SHIFT 16 #define SPIGCR1_CLKMOD_MASK BIT(1) #define SPIGCR1_MASTER_MASK BIT(0) #define SPIGCR1_LOOPBACK_MASK BIT(16) /* SPIBUF */ #define SPIBUF_TXFULL_MASK BIT(29) #define SPIBUF_RXEMPTY_MASK BIT(31) /* Error Masks */ #define SPIFLG_DLEN_ERR_MASK BIT(0) #define SPIFLG_TIMEOUT_MASK BIT(1) #define SPIFLG_PARERR_MASK BIT(2) #define SPIFLG_DESYNC_MASK BIT(3) #define SPIFLG_BITERR_MASK BIT(4) #define SPIFLG_OVRRUN_MASK BIT(6) #define SPIFLG_RX_INTR_MASK BIT(8) #define SPIFLG_TX_INTR_MASK BIT(9) #define SPIFLG_BUF_INIT_ACTIVE_MASK BIT(24) #define SPIFLG_MASK (SPIFLG_DLEN_ERR_MASK \ | SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \ | SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \ | SPIFLG_OVRRUN_MASK | SPIFLG_RX_INTR_MASK \ | SPIFLG_TX_INTR_MASK \ | SPIFLG_BUF_INIT_ACTIVE_MASK) #define SPIINT_DLEN_ERR_INTR BIT(0) #define SPIINT_TIMEOUT_INTR BIT(1) #define SPIINT_PARERR_INTR BIT(2) #define SPIINT_DESYNC_INTR BIT(3) #define SPIINT_BITERR_INTR BIT(4) #define SPIINT_OVRRUN_INTR BIT(6) #define SPIINT_RX_INTR BIT(8) #define SPIINT_TX_INTR BIT(9) #define SPIINT_DMA_REQ_EN BIT(16) #define SPIINT_ENABLE_HIGHZ BIT(24) #define SPI_T2CDELAY_SHIFT 16 #define SPI_C2TDELAY_SHIFT 24 /* SPI Controller registers */ #define SPIGCR0 0x00 #define SPIGCR1 0x04 #define SPIINT 0x08 #define SPILVL 0x0c #define SPIFLG 0x10 #define SPIPC0 0x14 #define SPIPC1 0x18 #define SPIPC2 0x1c #define SPIPC3 0x20 #define SPIPC4 0x24 #define SPIPC5 0x28 #define SPIPC6 0x2c #define SPIPC7 0x30 #define SPIPC8 0x34 #define SPIDAT0 0x38 #define SPIDAT1 0x3c #define SPIBUF 0x40 #define SPIEMU 0x44 #define SPIDELAY 0x48 #define SPIDEF 0x4c #define SPIFMT0 0x50 #define SPIFMT1 0x54 #define SPIFMT2 0x58 #define SPIFMT3 0x5c #define TGINTVEC0 0x60 #define TGINTVEC1 0x64 struct davinci_spi_slave { u32 cmd_to_write; u32 clk_ctrl_to_write; u32 bytes_per_word; u8 active_cs; }; /* We have 2 DMA channels per CS, one for RX and one for TX */ struct davinci_spi_dma { int dma_tx_channel; int dma_rx_channel; int dma_tx_sync_dev; int dma_rx_sync_dev; enum dma_event_q eventq; struct completion dma_tx_completion; struct completion dma_rx_completion; }; /* SPI Controller driver's private data. */ struct davinci_spi { struct spi_bitbang bitbang; struct clk *clk; u8 version; resource_size_t pbase; void __iomem *base; size_t region_size; u32 irq; struct completion done; const void *tx; void *rx; u8 *tmp_buf; int count; struct davinci_spi_dma *dma_channels; struct davinci_spi_platform_data *pdata; void (*get_rx)(u32 rx_data, struct davinci_spi *); u32 (*get_tx)(struct davinci_spi *); struct davinci_spi_slave slave[SPI_MAX_CHIPSELECT]; }; static unsigned use_dma; static void davinci_spi_rx_buf_u8(u32 data, struct davinci_spi *davinci_spi) { u8 *rx = davinci_spi->rx; *rx++ = (u8)data; davinci_spi->rx = rx; } static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *davinci_spi) { u16 *rx = davinci_spi->rx; *rx++ = (u16)data; davinci_spi->rx = rx; } static u32 davinci_spi_tx_buf_u8(struct davinci_spi *davinci_spi) { u32 data; const u8 *tx = davinci_spi->tx; data = *tx++; davinci_spi->tx = tx; return data; } static u32 davinci_spi_tx_buf_u16(struct davinci_spi *davinci_spi) { u32 data; const u16 *tx = davinci_spi->tx; data = *tx++; davinci_spi->tx = tx; return data; } static inline void set_io_bits(void __iomem *addr, u32 bits) { u32 v = ioread32(addr); v |= bits; iowrite32(v, addr); } static inline void clear_io_bits(void __iomem *addr, u32 bits) { u32 v = ioread32(addr); v &= ~bits; iowrite32(v, addr); } static inline void set_fmt_bits(void __iomem *addr, u32 bits, int cs_num) { set_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits); } static inline void clear_fmt_bits(void __iomem *addr, u32 bits, int cs_num) { clear_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits); } static void davinci_spi_set_dma_req(const struct spi_device *spi, int enable) { struct davinci_spi *davinci_spi = spi_master_get_devdata(spi->master); if (enable) set_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); else clear_io_bits(davinci_spi->base + SPIINT, SPIINT_DMA_REQ_EN); } /* * Interface to control the chip select signal */ static void davinci_spi_chipselect(struct spi_device *spi, int value) { struct davinci_spi *davinci_spi; struct davinci_spi_platform_data *pdata; u32 data1_reg_val = 0; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; /* * Board specific chip select logic decides the polarity and cs * line for the controller */ if (value == BITBANG_CS_INACTIVE) { set_io_bits(davinci_spi->base + SPIDEF, CS_DEFAULT); data1_reg_val |= CS_DEFAULT << SPIDAT1_CSNR_SHIFT; iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); while ((ioread32(davinci_spi->base + SPIBUF) & SPIBUF_RXEMPTY_MASK) == 0) cpu_relax(); } } /** * davinci_spi_setup_transfer - This functions will determine transfer method * @spi: spi device on which data transfer to be done * @t: spi transfer in which transfer info is filled * * This function determines data transfer method (8/16/32 bit transfer). * It will also set the SPI Clock Control register according to * SPI slave device freq. */ static int davinci_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { struct davinci_spi *davinci_spi; struct davinci_spi_platform_data *pdata; u8 bits_per_word = 0; u32 hz = 0, prescale = 0, clkspeed; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; if (t) { bits_per_word = t->bits_per_word; hz = t->speed_hz; } /* if bits_per_word is not set then set it default */ if (!bits_per_word) bits_per_word = spi->bits_per_word; /* * Assign function pointer to appropriate transfer method * 8bit, 16bit or 32bit transfer */ if (bits_per_word <= 8 && bits_per_word >= 2) { davinci_spi->get_rx = davinci_spi_rx_buf_u8; davinci_spi->get_tx = davinci_spi_tx_buf_u8; davinci_spi->slave[spi->chip_select].bytes_per_word = 1; } else if (bits_per_word <= 16 && bits_per_word >= 2) { davinci_spi->get_rx = davinci_spi_rx_buf_u16; davinci_spi->get_tx = davinci_spi_tx_buf_u16; davinci_spi->slave[spi->chip_select].bytes_per_word = 2; } else return -EINVAL; if (!hz) hz = spi->max_speed_hz; clear_fmt_bits(davinci_spi->base, SPIFMT_CHARLEN_MASK, spi->chip_select); set_fmt_bits(davinci_spi->base, bits_per_word & 0x1f, spi->chip_select); clkspeed = clk_get_rate(davinci_spi->clk); if (hz > clkspeed / 2) prescale = 1 << 8; if (hz < clkspeed / 256) prescale = 255 << 8; if (!prescale) prescale = ((clkspeed / hz - 1) << 8) & 0x0000ff00; clear_fmt_bits(davinci_spi->base, 0x0000ff00, spi->chip_select); set_fmt_bits(davinci_spi->base, prescale, spi->chip_select); return 0; } static void davinci_spi_dma_rx_callback(unsigned lch, u16 ch_status, void *data) { struct spi_device *spi = (struct spi_device *)data; struct davinci_spi *davinci_spi; struct davinci_spi_dma *davinci_spi_dma; struct davinci_spi_platform_data *pdata; davinci_spi = spi_master_get_devdata(spi->master); davinci_spi_dma = &(davinci_spi->dma_channels[spi->chip_select]); pdata = davinci_spi->pdata; if (ch_status == DMA_COMPLETE) edma_stop(davinci_spi_dma->dma_rx_channel); else edma_clean_channel(davinci_spi_dma->dma_rx_channel); complete(&davinci_spi_dma->dma_rx_completion); /* We must disable the DMA RX request */ davinci_spi_set_dma_req(spi, 0); } static void davinci_spi_dma_tx_callback(unsigned lch, u16 ch_status, void *data) { struct spi_device *spi = (struct spi_device *)data; struct davinci_spi *davinci_spi; struct davinci_spi_dma *davinci_spi_dma; struct davinci_spi_platform_data *pdata; davinci_spi = spi_master_get_devdata(spi->master); davinci_spi_dma = &(davinci_spi->dma_channels[spi->chip_select]); pdata = davinci_spi->pdata; if (ch_status == DMA_COMPLETE) edma_stop(davinci_spi_dma->dma_tx_channel); else edma_clean_channel(davinci_spi_dma->dma_tx_channel); complete(&davinci_spi_dma->dma_tx_completion); /* We must disable the DMA TX request */ davinci_spi_set_dma_req(spi, 0); } static int davinci_spi_request_dma(struct spi_device *spi) { struct davinci_spi *davinci_spi; struct davinci_spi_dma *davinci_spi_dma; struct davinci_spi_platform_data *pdata; struct device *sdev; int r; davinci_spi = spi_master_get_devdata(spi->master); davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select]; pdata = davinci_spi->pdata; sdev = davinci_spi->bitbang.master->dev.parent; r = edma_alloc_channel(davinci_spi_dma->dma_rx_sync_dev, davinci_spi_dma_rx_callback, spi, davinci_spi_dma->eventq); if (r < 0) { dev_dbg(sdev, "Unable to request DMA channel for SPI RX\n"); return -EAGAIN; } davinci_spi_dma->dma_rx_channel = r; r = edma_alloc_channel(davinci_spi_dma->dma_tx_sync_dev, davinci_spi_dma_tx_callback, spi, davinci_spi_dma->eventq); if (r < 0) { edma_free_channel(davinci_spi_dma->dma_rx_channel); davinci_spi_dma->dma_rx_channel = -1; dev_dbg(sdev, "Unable to request DMA channel for SPI TX\n"); return -EAGAIN; } davinci_spi_dma->dma_tx_channel = r; return 0; } /** * davinci_spi_setup - This functions will set default transfer method * @spi: spi device on which data transfer to be done * * This functions sets the default transfer method. */ static int davinci_spi_setup(struct spi_device *spi) { int retval; struct davinci_spi *davinci_spi; struct davinci_spi_dma *davinci_spi_dma; struct device *sdev; davinci_spi = spi_master_get_devdata(spi->master); sdev = davinci_spi->bitbang.master->dev.parent; /* if bits per word length is zero then set it default 8 */ if (!spi->bits_per_word) spi->bits_per_word = 8; davinci_spi->slave[spi->chip_select].cmd_to_write = 0; if (use_dma && davinci_spi->dma_channels) { davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select]; if ((davinci_spi_dma->dma_rx_channel == -1) || (davinci_spi_dma->dma_tx_channel == -1)) { retval = davinci_spi_request_dma(spi); if (retval < 0) return retval; } } /* * SPI in DaVinci and DA8xx operate between * 600 KHz and 50 MHz */ if (spi->max_speed_hz < 600000 || spi->max_speed_hz > 50000000) { dev_dbg(sdev, "Operating frequency is not in acceptable " "range\n"); return -EINVAL; } /* * Set up SPIFMTn register, unique to this chipselect. * * NOTE: we could do all of these with one write. Also, some * of the "version 2" features are found in chips that don't * support all of them... */ if (spi->mode & SPI_LSB_FIRST) set_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK, spi->chip_select); if (spi->mode & SPI_CPOL) set_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK, spi->chip_select); if (!(spi->mode & SPI_CPHA)) set_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK, spi->chip_select); /* * Version 1 hardware supports two basic SPI modes: * - Standard SPI mode uses 4 pins, with chipselect * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS) * (distinct from SPI_3WIRE, with just one data wire; * or similar variants without MOSI or without MISO) * * Version 2 hardware supports an optional handshaking signal, * so it can support two more modes: * - 5 pin SPI variant is standard SPI plus SPI_READY * - 4 pin with enable is (SPI_READY | SPI_NO_CS) */ if (davinci_spi->version == SPI_VERSION_2) { clear_fmt_bits(davinci_spi->base, SPIFMT_WDELAY_MASK, spi->chip_select); set_fmt_bits(davinci_spi->base, (davinci_spi->pdata->wdelay << SPIFMT_WDELAY_SHIFT) & SPIFMT_WDELAY_MASK, spi->chip_select); if (davinci_spi->pdata->odd_parity) set_fmt_bits(davinci_spi->base, SPIFMT_ODD_PARITY_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_ODD_PARITY_MASK, spi->chip_select); if (davinci_spi->pdata->parity_enable) set_fmt_bits(davinci_spi->base, SPIFMT_PARITYENA_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_PARITYENA_MASK, spi->chip_select); if (davinci_spi->pdata->wait_enable) set_fmt_bits(davinci_spi->base, SPIFMT_WAITENA_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_WAITENA_MASK, spi->chip_select); if (davinci_spi->pdata->timer_disable) set_fmt_bits(davinci_spi->base, SPIFMT_DISTIMER_MASK, spi->chip_select); else clear_fmt_bits(davinci_spi->base, SPIFMT_DISTIMER_MASK, spi->chip_select); } retval = davinci_spi_setup_transfer(spi, NULL); return retval; } static void davinci_spi_cleanup(struct spi_device *spi) { struct davinci_spi *davinci_spi = spi_master_get_devdata(spi->master); struct davinci_spi_dma *davinci_spi_dma; davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select]; if (use_dma && davinci_spi->dma_channels) { davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select]; if ((davinci_spi_dma->dma_rx_channel != -1) && (davinci_spi_dma->dma_tx_channel != -1)) { edma_free_channel(davinci_spi_dma->dma_tx_channel); edma_free_channel(davinci_spi_dma->dma_rx_channel); } } } static int davinci_spi_bufs_prep(struct spi_device *spi, struct davinci_spi *davinci_spi) { int op_mode = 0; /* * REVISIT unless devices disagree about SPI_LOOP or * SPI_READY (SPI_NO_CS only allows one device!), this * should not need to be done before each message... * optimize for both flags staying cleared. */ op_mode = SPIPC0_DIFUN_MASK | SPIPC0_DOFUN_MASK | SPIPC0_CLKFUN_MASK; if (!(spi->mode & SPI_NO_CS)) op_mode |= 1 << spi->chip_select; if (spi->mode & SPI_READY) op_mode |= SPIPC0_SPIENA_MASK; iowrite32(op_mode, davinci_spi->base + SPIPC0); if (spi->mode & SPI_LOOP) set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK); else clear_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK); return 0; } static int davinci_spi_check_error(struct davinci_spi *davinci_spi, int int_status) { struct device *sdev = davinci_spi->bitbang.master->dev.parent; if (int_status & SPIFLG_TIMEOUT_MASK) { dev_dbg(sdev, "SPI Time-out Error\n"); return -ETIMEDOUT; } if (int_status & SPIFLG_DESYNC_MASK) { dev_dbg(sdev, "SPI Desynchronization Error\n"); return -EIO; } if (int_status & SPIFLG_BITERR_MASK) { dev_dbg(sdev, "SPI Bit error\n"); return -EIO; } if (davinci_spi->version == SPI_VERSION_2) { if (int_status & SPIFLG_DLEN_ERR_MASK) { dev_dbg(sdev, "SPI Data Length Error\n"); return -EIO; } if (int_status & SPIFLG_PARERR_MASK) { dev_dbg(sdev, "SPI Parity Error\n"); return -EIO; } if (int_status & SPIFLG_OVRRUN_MASK) { dev_dbg(sdev, "SPI Data Overrun error\n"); return -EIO; } if (int_status & SPIFLG_TX_INTR_MASK) { dev_dbg(sdev, "SPI TX intr bit set\n"); return -EIO; } if (int_status & SPIFLG_BUF_INIT_ACTIVE_MASK) { dev_dbg(sdev, "SPI Buffer Init Active\n"); return -EBUSY; } } return 0; } /** * davinci_spi_bufs - functions which will handle transfer data * @spi: spi device on which data transfer to be done * @t: spi transfer in which transfer info is filled * * This function will put data to be transferred into data register * of SPI controller and then wait until the completion will be marked * by the IRQ Handler. */ static int davinci_spi_bufs_pio(struct spi_device *spi, struct spi_transfer *t) { struct davinci_spi *davinci_spi; int int_status, count, ret; u8 conv, tmp; u32 tx_data, data1_reg_val; u32 buf_val, flg_val; struct davinci_spi_platform_data *pdata; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; davinci_spi->tx = t->tx_buf; davinci_spi->rx = t->rx_buf; /* convert len to words based on bits_per_word */ conv = davinci_spi->slave[spi->chip_select].bytes_per_word; davinci_spi->count = t->len / conv; INIT_COMPLETION(davinci_spi->done); ret = davinci_spi_bufs_prep(spi, davinci_spi); if (ret) return ret; /* Enable SPI */ set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); iowrite32(0 | (pdata->c2tdelay << SPI_C2TDELAY_SHIFT) | (pdata->t2cdelay << SPI_T2CDELAY_SHIFT), davinci_spi->base + SPIDELAY); count = davinci_spi->count; data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT; tmp = ~(0x1 << spi->chip_select); clear_io_bits(davinci_spi->base + SPIDEF, ~tmp); data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT; while ((ioread32(davinci_spi->base + SPIBUF) & SPIBUF_RXEMPTY_MASK) == 0) cpu_relax(); /* Determine the command to execute READ or WRITE */ if (t->tx_buf) { clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL); while (1) { tx_data = davinci_spi->get_tx(davinci_spi); data1_reg_val &= ~(0xFFFF); data1_reg_val |= (0xFFFF & tx_data); buf_val = ioread32(davinci_spi->base + SPIBUF); if ((buf_val & SPIBUF_TXFULL_MASK) == 0) { iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); count--; } while (ioread32(davinci_spi->base + SPIBUF) & SPIBUF_RXEMPTY_MASK) cpu_relax(); /* getting the returned byte */ if (t->rx_buf) { buf_val = ioread32(davinci_spi->base + SPIBUF); davinci_spi->get_rx(buf_val, davinci_spi); } if (count <= 0) break; } } else { if (pdata->poll_mode) { while (1) { /* keeps the serial clock going */ if ((ioread32(davinci_spi->base + SPIBUF) & SPIBUF_TXFULL_MASK) == 0) iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); while (ioread32(davinci_spi->base + SPIBUF) & SPIBUF_RXEMPTY_MASK) cpu_relax(); flg_val = ioread32(davinci_spi->base + SPIFLG); buf_val = ioread32(davinci_spi->base + SPIBUF); davinci_spi->get_rx(buf_val, davinci_spi); count--; if (count <= 0) break; } } else { /* Receive in Interrupt mode */ int i; for (i = 0; i < davinci_spi->count; i++) { set_io_bits(davinci_spi->base + SPIINT, SPIINT_BITERR_INTR | SPIINT_OVRRUN_INTR | SPIINT_RX_INTR); iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); while (ioread32(davinci_spi->base + SPIINT) & SPIINT_RX_INTR) cpu_relax(); } iowrite32((data1_reg_val & 0x0ffcffff), davinci_spi->base + SPIDAT1); } } /* * Check for bit error, desync error,parity error,timeout error and * receive overflow errors */ int_status = ioread32(davinci_spi->base + SPIFLG); ret = davinci_spi_check_error(davinci_spi, int_status); if (ret != 0) return ret; /* SPI Framework maintains the count only in bytes so convert back */ davinci_spi->count *= conv; return t->len; } #define DAVINCI_DMA_DATA_TYPE_S8 0x01 #define DAVINCI_DMA_DATA_TYPE_S16 0x02 #define DAVINCI_DMA_DATA_TYPE_S32 0x04 static int davinci_spi_bufs_dma(struct spi_device *spi, struct spi_transfer *t) { struct davinci_spi *davinci_spi; int int_status = 0; int count, temp_count; u8 conv = 1; u8 tmp; u32 data1_reg_val; struct davinci_spi_dma *davinci_spi_dma; int word_len, data_type, ret; unsigned long tx_reg, rx_reg; struct davinci_spi_platform_data *pdata; struct device *sdev; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; sdev = davinci_spi->bitbang.master->dev.parent; davinci_spi_dma = &davinci_spi->dma_channels[spi->chip_select]; tx_reg = (unsigned long)davinci_spi->pbase + SPIDAT1; rx_reg = (unsigned long)davinci_spi->pbase + SPIBUF; davinci_spi->tx = t->tx_buf; davinci_spi->rx = t->rx_buf; /* convert len to words based on bits_per_word */ conv = davinci_spi->slave[spi->chip_select].bytes_per_word; davinci_spi->count = t->len / conv; INIT_COMPLETION(davinci_spi->done); init_completion(&davinci_spi_dma->dma_rx_completion); init_completion(&davinci_spi_dma->dma_tx_completion); word_len = conv * 8; if (word_len <= 8) data_type = DAVINCI_DMA_DATA_TYPE_S8; else if (word_len <= 16) data_type = DAVINCI_DMA_DATA_TYPE_S16; else if (word_len <= 32) data_type = DAVINCI_DMA_DATA_TYPE_S32; else return -EINVAL; ret = davinci_spi_bufs_prep(spi, davinci_spi); if (ret) return ret; /* Put delay val if required */ iowrite32(0 | (pdata->c2tdelay << SPI_C2TDELAY_SHIFT) | (pdata->t2cdelay << SPI_T2CDELAY_SHIFT), davinci_spi->base + SPIDELAY); count = davinci_spi->count; /* the number of elements */ data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT; /* CS default = 0xFF */ tmp = ~(0x1 << spi->chip_select); clear_io_bits(davinci_spi->base + SPIDEF, ~tmp); data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT; /* disable all interrupts for dma transfers */ clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL); /* Disable SPI to write configuration bits in SPIDAT */ clear_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); /* Enable SPI */ set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK); while ((ioread32(davinci_spi->base + SPIBUF) & SPIBUF_RXEMPTY_MASK) == 0) cpu_relax(); if (t->tx_buf) { t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf, count, DMA_TO_DEVICE); if (dma_mapping_error(&spi->dev, t->tx_dma)) { dev_dbg(sdev, "Unable to DMA map a %d bytes" " TX buffer\n", count); return -ENOMEM; } temp_count = count; } else { /* We need TX clocking for RX transaction */ t->tx_dma = dma_map_single(&spi->dev, (void *)davinci_spi->tmp_buf, count + 1, DMA_TO_DEVICE); if (dma_mapping_error(&spi->dev, t->tx_dma)) { dev_dbg(sdev, "Unable to DMA map a %d bytes" " TX tmp buffer\n", count); return -ENOMEM; } temp_count = count + 1; } edma_set_transfer_params(davinci_spi_dma->dma_tx_channel, data_type, temp_count, 1, 0, ASYNC); edma_set_dest(davinci_spi_dma->dma_tx_channel, tx_reg, INCR, W8BIT); edma_set_src(davinci_spi_dma->dma_tx_channel, t->tx_dma, INCR, W8BIT); edma_set_src_index(davinci_spi_dma->dma_tx_channel, data_type, 0); edma_set_dest_index(davinci_spi_dma->dma_tx_channel, 0, 0); if (t->rx_buf) { /* initiate transaction */ iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1); t->rx_dma = dma_map_single(&spi->dev, (void *)t->rx_buf, count, DMA_FROM_DEVICE); if (dma_mapping_error(&spi->dev, t->rx_dma)) { dev_dbg(sdev, "Couldn't DMA map a %d bytes RX buffer\n", count); if (t->tx_buf != NULL) dma_unmap_single(NULL, t->tx_dma, count, DMA_TO_DEVICE); return -ENOMEM; } edma_set_transfer_params(davinci_spi_dma->dma_rx_channel, data_type, count, 1, 0, ASYNC); edma_set_src(davinci_spi_dma->dma_rx_channel, rx_reg, INCR, W8BIT); edma_set_dest(davinci_spi_dma->dma_rx_channel, t->rx_dma, INCR, W8BIT); edma_set_src_index(davinci_spi_dma->dma_rx_channel, 0, 0); edma_set_dest_index(davinci_spi_dma->dma_rx_channel, data_type, 0); } if ((t->tx_buf) || (t->rx_buf)) edma_start(davinci_spi_dma->dma_tx_channel); if (t->rx_buf) edma_start(davinci_spi_dma->dma_rx_channel); if ((t->rx_buf) || (t->tx_buf)) davinci_spi_set_dma_req(spi, 1); if (t->tx_buf) wait_for_completion_interruptible( &davinci_spi_dma->dma_tx_completion); if (t->rx_buf) wait_for_completion_interruptible( &davinci_spi_dma->dma_rx_completion); dma_unmap_single(NULL, t->tx_dma, temp_count, DMA_TO_DEVICE); if (t->rx_buf) dma_unmap_single(NULL, t->rx_dma, count, DMA_FROM_DEVICE); /* * Check for bit error, desync error,parity error,timeout error and * receive overflow errors */ int_status = ioread32(davinci_spi->base + SPIFLG); ret = davinci_spi_check_error(davinci_spi, int_status); if (ret != 0) return ret; /* SPI Framework maintains the count only in bytes so convert back */ davinci_spi->count *= conv; return t->len; } /** * davinci_spi_irq - IRQ handler for DaVinci SPI * @irq: IRQ number for this SPI Master * @context_data: structure for SPI Master controller davinci_spi */ static irqreturn_t davinci_spi_irq(s32 irq, void *context_data) { struct davinci_spi *davinci_spi = context_data; u32 int_status, rx_data = 0; irqreturn_t ret = IRQ_NONE; int_status = ioread32(davinci_spi->base + SPIFLG); while ((int_status & SPIFLG_RX_INTR_MASK)) { if (likely(int_status & SPIFLG_RX_INTR_MASK)) { ret = IRQ_HANDLED; rx_data = ioread32(davinci_spi->base + SPIBUF); davinci_spi->get_rx(rx_data, davinci_spi); /* Disable Receive Interrupt */ iowrite32(~(SPIINT_RX_INTR | SPIINT_TX_INTR), davinci_spi->base + SPIINT); } else (void)davinci_spi_check_error(davinci_spi, int_status); int_status = ioread32(davinci_spi->base + SPIFLG); } return ret; } /** * davinci_spi_probe - probe function for SPI Master Controller * @pdev: platform_device structure which contains plateform specific data */ static int davinci_spi_probe(struct platform_device *pdev) { struct spi_master *master; struct davinci_spi *davinci_spi; struct davinci_spi_platform_data *pdata; struct resource *r, *mem; resource_size_t dma_rx_chan = SPI_NO_RESOURCE; resource_size_t dma_tx_chan = SPI_NO_RESOURCE; resource_size_t dma_eventq = SPI_NO_RESOURCE; int i = 0, ret = 0; pdata = pdev->dev.platform_data; if (pdata == NULL) { ret = -ENODEV; goto err; } master = spi_alloc_master(&pdev->dev, sizeof(struct davinci_spi)); if (master == NULL) { ret = -ENOMEM; goto err; } dev_set_drvdata(&pdev->dev, master); davinci_spi = spi_master_get_devdata(master); if (davinci_spi == NULL) { ret = -ENOENT; goto free_master; } r = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (r == NULL) { ret = -ENOENT; goto free_master; } davinci_spi->pbase = r->start; davinci_spi->region_size = resource_size(r); davinci_spi->pdata = pdata; mem = request_mem_region(r->start, davinci_spi->region_size, pdev->name); if (mem == NULL) { ret = -EBUSY; goto free_master; } davinci_spi->base = (struct davinci_spi_reg __iomem *) ioremap(r->start, davinci_spi->region_size); if (davinci_spi->base == NULL) { ret = -ENOMEM; goto release_region; } davinci_spi->irq = platform_get_irq(pdev, 0); if (davinci_spi->irq <= 0) { ret = -EINVAL; goto unmap_io; } ret = request_irq(davinci_spi->irq, davinci_spi_irq, IRQF_DISABLED, dev_name(&pdev->dev), davinci_spi); if (ret) goto unmap_io; /* Allocate tmp_buf for tx_buf */ davinci_spi->tmp_buf = kzalloc(SPI_BUFSIZ, GFP_KERNEL); if (davinci_spi->tmp_buf == NULL) { ret = -ENOMEM; goto irq_free; } davinci_spi->bitbang.master = spi_master_get(master); if (davinci_spi->bitbang.master == NULL) { ret = -ENODEV; goto free_tmp_buf; } davinci_spi->clk = clk_get(&pdev->dev, NULL); if (IS_ERR(davinci_spi->clk)) { ret = -ENODEV; goto put_master; } clk_enable(davinci_spi->clk); master->bus_num = pdev->id; master->num_chipselect = pdata->num_chipselect; master->setup = davinci_spi_setup; master->cleanup = davinci_spi_cleanup; davinci_spi->bitbang.chipselect = davinci_spi_chipselect; davinci_spi->bitbang.setup_transfer = davinci_spi_setup_transfer; davinci_spi->version = pdata->version; use_dma = pdata->use_dma; davinci_spi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP; if (davinci_spi->version == SPI_VERSION_2) davinci_spi->bitbang.flags |= SPI_READY; if (use_dma) { r = platform_get_resource(pdev, IORESOURCE_DMA, 0); if (r) dma_rx_chan = r->start; r = platform_get_resource(pdev, IORESOURCE_DMA, 1); if (r) dma_tx_chan = r->start; r = platform_get_resource(pdev, IORESOURCE_DMA, 2); if (r) dma_eventq = r->start; } if (!use_dma || dma_rx_chan == SPI_NO_RESOURCE || dma_tx_chan == SPI_NO_RESOURCE || dma_eventq == SPI_NO_RESOURCE) { davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_pio; use_dma = 0; } else { davinci_spi->bitbang.txrx_bufs = davinci_spi_bufs_dma; davinci_spi->dma_channels = kzalloc(master->num_chipselect * sizeof(struct davinci_spi_dma), GFP_KERNEL); if (davinci_spi->dma_channels == NULL) { ret = -ENOMEM; goto free_clk; } for (i = 0; i < master->num_chipselect; i++) { davinci_spi->dma_channels[i].dma_rx_channel = -1; davinci_spi->dma_channels[i].dma_rx_sync_dev = dma_rx_chan; davinci_spi->dma_channels[i].dma_tx_channel = -1; davinci_spi->dma_channels[i].dma_tx_sync_dev = dma_tx_chan; davinci_spi->dma_channels[i].eventq = dma_eventq; } dev_info(&pdev->dev, "DaVinci SPI driver in EDMA mode\n" "Using RX channel = %d , TX channel = %d and " "event queue = %d", dma_rx_chan, dma_tx_chan, dma_eventq); } davinci_spi->get_rx = davinci_spi_rx_buf_u8; davinci_spi->get_tx = davinci_spi_tx_buf_u8; init_completion(&davinci_spi->done); /* Reset In/OUT SPI module */ iowrite32(0, davinci_spi->base + SPIGCR0); udelay(100); iowrite32(1, davinci_spi->base + SPIGCR0); /* Clock internal */ if (davinci_spi->pdata->clk_internal) set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_CLKMOD_MASK); else clear_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_CLKMOD_MASK); /* master mode default */ set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_MASTER_MASK); if (davinci_spi->pdata->intr_level) iowrite32(SPI_INTLVL_1, davinci_spi->base + SPILVL); else iowrite32(SPI_INTLVL_0, davinci_spi->base + SPILVL); ret = spi_bitbang_start(&davinci_spi->bitbang); if (ret) goto free_clk; dev_info(&pdev->dev, "Controller at 0x%p \n", davinci_spi->base); if (!pdata->poll_mode) dev_info(&pdev->dev, "Operating in interrupt mode" " using IRQ %d\n", davinci_spi->irq); return ret; free_clk: clk_disable(davinci_spi->clk); clk_put(davinci_spi->clk); put_master: spi_master_put(master); free_tmp_buf: kfree(davinci_spi->tmp_buf); irq_free: free_irq(davinci_spi->irq, davinci_spi); unmap_io: iounmap(davinci_spi->base); release_region: release_mem_region(davinci_spi->pbase, davinci_spi->region_size); free_master: kfree(master); err: return ret; } /** * davinci_spi_remove - remove function for SPI Master Controller * @pdev: platform_device structure which contains plateform specific data * * This function will do the reverse action of davinci_spi_probe function * It will free the IRQ and SPI controller's memory region. * It will also call spi_bitbang_stop to destroy the work queue which was * created by spi_bitbang_start. */ static int __exit davinci_spi_remove(struct platform_device *pdev) { struct davinci_spi *davinci_spi; struct spi_master *master; master = dev_get_drvdata(&pdev->dev); davinci_spi = spi_master_get_devdata(master); spi_bitbang_stop(&davinci_spi->bitbang); clk_disable(davinci_spi->clk); clk_put(davinci_spi->clk); spi_master_put(master); kfree(davinci_spi->tmp_buf); free_irq(davinci_spi->irq, davinci_spi); iounmap(davinci_spi->base); release_mem_region(davinci_spi->pbase, davinci_spi->region_size); return 0; } static struct platform_driver davinci_spi_driver = { .driver.name = "spi_davinci", .remove = __exit_p(davinci_spi_remove), }; static int __init davinci_spi_init(void) { return platform_driver_probe(&davinci_spi_driver, davinci_spi_probe); } module_init(davinci_spi_init); static void __exit davinci_spi_exit(void) { platform_driver_unregister(&davinci_spi_driver); } module_exit(davinci_spi_exit); MODULE_DESCRIPTION("TI DaVinci SPI Master Controller Driver"); MODULE_LICENSE("GPL");