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authorGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
committerGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
commitca632f556697d45d67ed5cada7cedf3ddfe0db4b (patch)
treef393534b929abb32813ea5c495f1ac6d93a10d1d /drivers/spi/davinci_spi.c
parent8c99268431a117207a89be5167ecd69429fd4bda (diff)
spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/spi/davinci_spi.c')
-rw-r--r--drivers/spi/davinci_spi.c1030
1 files changed, 0 insertions, 1030 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
deleted file mode 100644
index 1f0ed8005c9..00000000000
--- a/drivers/spi/davinci_spi.c
+++ /dev/null
@@ -1,1030 +0,0 @@
-/*
- * Copyright (C) 2009 Texas Instruments.
- * Copyright (C) 2010 EF Johnson Technologies
- *
- * 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 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_PRESCALE_SHIFT 8
-
-/* 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 SPIINT_MASKALL 0x0101035F
-#define SPIINT_MASKINT 0x0000015F
-#define SPI_INTLVL_1 0x000001FF
-#define SPI_INTLVL_0 0x00000000
-
-/* SPIDAT1 (upper 16 bit defines) */
-#define SPIDAT1_CSHOLD_MASK BIT(12)
-
-/* SPIGCR1 */
-#define SPIGCR1_CLKMOD_MASK BIT(1)
-#define SPIGCR1_MASTER_MASK BIT(0)
-#define SPIGCR1_POWERDOWN_MASK BIT(8)
-#define SPIGCR1_LOOPBACK_MASK BIT(16)
-#define SPIGCR1_SPIENA_MASK BIT(24)
-
-/* SPIBUF */
-#define SPIBUF_TXFULL_MASK BIT(29)
-#define SPIBUF_RXEMPTY_MASK BIT(31)
-
-/* SPIDELAY */
-#define SPIDELAY_C2TDELAY_SHIFT 24
-#define SPIDELAY_C2TDELAY_MASK (0xFF << SPIDELAY_C2TDELAY_SHIFT)
-#define SPIDELAY_T2CDELAY_SHIFT 16
-#define SPIDELAY_T2CDELAY_MASK (0xFF << SPIDELAY_T2CDELAY_SHIFT)
-#define SPIDELAY_T2EDELAY_SHIFT 8
-#define SPIDELAY_T2EDELAY_MASK (0xFF << SPIDELAY_T2EDELAY_SHIFT)
-#define SPIDELAY_C2EDELAY_SHIFT 0
-#define SPIDELAY_C2EDELAY_MASK 0xFF
-
-/* 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_BUF_INIT_ACTIVE_MASK BIT(24)
-#define SPIFLG_ERROR_MASK (SPIFLG_DLEN_ERR_MASK \
- | SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \
- | SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \
- | SPIFLG_OVRRUN_MASK)
-
-#define SPIINT_DMA_REQ_EN BIT(16)
-
-/* SPI Controller registers */
-#define SPIGCR0 0x00
-#define SPIGCR1 0x04
-#define SPIINT 0x08
-#define SPILVL 0x0c
-#define SPIFLG 0x10
-#define SPIPC0 0x14
-#define SPIDAT1 0x3c
-#define SPIBUF 0x40
-#define SPIDELAY 0x48
-#define SPIDEF 0x4c
-#define SPIFMT0 0x50
-
-/* We have 2 DMA channels per CS, one for RX and one for TX */
-struct davinci_spi_dma {
- int tx_channel;
- int rx_channel;
- int dummy_param_slot;
- enum dma_event_q eventq;
-};
-
-/* 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;
- u32 irq;
- struct completion done;
-
- const void *tx;
- void *rx;
-#define SPI_TMP_BUFSZ (SMP_CACHE_BYTES + 1)
- u8 rx_tmp_buf[SPI_TMP_BUFSZ];
- int rcount;
- int wcount;
- struct davinci_spi_dma dma;
- struct davinci_spi_platform_data *pdata;
-
- void (*get_rx)(u32 rx_data, struct davinci_spi *);
- u32 (*get_tx)(struct davinci_spi *);
-
- u8 bytes_per_word[SPI_MAX_CHIPSELECT];
-};
-
-static struct davinci_spi_config davinci_spi_default_cfg;
-
-static void davinci_spi_rx_buf_u8(u32 data, struct davinci_spi *dspi)
-{
- if (dspi->rx) {
- u8 *rx = dspi->rx;
- *rx++ = (u8)data;
- dspi->rx = rx;
- }
-}
-
-static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *dspi)
-{
- if (dspi->rx) {
- u16 *rx = dspi->rx;
- *rx++ = (u16)data;
- dspi->rx = rx;
- }
-}
-
-static u32 davinci_spi_tx_buf_u8(struct davinci_spi *dspi)
-{
- u32 data = 0;
- if (dspi->tx) {
- const u8 *tx = dspi->tx;
- data = *tx++;
- dspi->tx = tx;
- }
- return data;
-}
-
-static u32 davinci_spi_tx_buf_u16(struct davinci_spi *dspi)
-{
- u32 data = 0;
- if (dspi->tx) {
- const u16 *tx = dspi->tx;
- data = *tx++;
- dspi->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);
-}
-
-/*
- * Interface to control the chip select signal
- */
-static void davinci_spi_chipselect(struct spi_device *spi, int value)
-{
- struct davinci_spi *dspi;
- struct davinci_spi_platform_data *pdata;
- u8 chip_sel = spi->chip_select;
- u16 spidat1 = CS_DEFAULT;
- bool gpio_chipsel = false;
-
- dspi = spi_master_get_devdata(spi->master);
- pdata = dspi->pdata;
-
- if (pdata->chip_sel && chip_sel < pdata->num_chipselect &&
- pdata->chip_sel[chip_sel] != SPI_INTERN_CS)
- gpio_chipsel = true;
-
- /*
- * Board specific chip select logic decides the polarity and cs
- * line for the controller
- */
- if (gpio_chipsel) {
- if (value == BITBANG_CS_ACTIVE)
- gpio_set_value(pdata->chip_sel[chip_sel], 0);
- else
- gpio_set_value(pdata->chip_sel[chip_sel], 1);
- } else {
- if (value == BITBANG_CS_ACTIVE) {
- spidat1 |= SPIDAT1_CSHOLD_MASK;
- spidat1 &= ~(0x1 << chip_sel);
- }
-
- iowrite16(spidat1, dspi->base + SPIDAT1 + 2);
- }
-}
-
-/**
- * davinci_spi_get_prescale - Calculates the correct prescale value
- * @maxspeed_hz: the maximum rate the SPI clock can run at
- *
- * This function calculates the prescale value that generates a clock rate
- * less than or equal to the specified maximum.
- *
- * Returns: calculated prescale - 1 for easy programming into SPI registers
- * or negative error number if valid prescalar cannot be updated.
- */
-static inline int davinci_spi_get_prescale(struct davinci_spi *dspi,
- u32 max_speed_hz)
-{
- int ret;
-
- ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz);
-
- if (ret < 3 || ret > 256)
- return -EINVAL;
-
- return ret - 1;
-}
-
-/**
- * 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 *dspi;
- struct davinci_spi_config *spicfg;
- u8 bits_per_word = 0;
- u32 hz = 0, spifmt = 0, prescale = 0;
-
- dspi = spi_master_get_devdata(spi->master);
- spicfg = (struct davinci_spi_config *)spi->controller_data;
- if (!spicfg)
- spicfg = &davinci_spi_default_cfg;
-
- 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) {
- dspi->get_rx = davinci_spi_rx_buf_u8;
- dspi->get_tx = davinci_spi_tx_buf_u8;
- dspi->bytes_per_word[spi->chip_select] = 1;
- } else if (bits_per_word <= 16 && bits_per_word >= 2) {
- dspi->get_rx = davinci_spi_rx_buf_u16;
- dspi->get_tx = davinci_spi_tx_buf_u16;
- dspi->bytes_per_word[spi->chip_select] = 2;
- } else
- return -EINVAL;
-
- if (!hz)
- hz = spi->max_speed_hz;
-
- /* Set up SPIFMTn register, unique to this chipselect. */
-
- prescale = davinci_spi_get_prescale(dspi, hz);
- if (prescale < 0)
- return prescale;
-
- spifmt = (prescale << SPIFMT_PRESCALE_SHIFT) | (bits_per_word & 0x1f);
-
- if (spi->mode & SPI_LSB_FIRST)
- spifmt |= SPIFMT_SHIFTDIR_MASK;
-
- if (spi->mode & SPI_CPOL)
- spifmt |= SPIFMT_POLARITY_MASK;
-
- if (!(spi->mode & SPI_CPHA))
- spifmt |= SPIFMT_PHASE_MASK;
-
- /*
- * 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 (dspi->version == SPI_VERSION_2) {
-
- u32 delay = 0;
-
- spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT)
- & SPIFMT_WDELAY_MASK);
-
- if (spicfg->odd_parity)
- spifmt |= SPIFMT_ODD_PARITY_MASK;
-
- if (spicfg->parity_enable)
- spifmt |= SPIFMT_PARITYENA_MASK;
-
- if (spicfg->timer_disable) {
- spifmt |= SPIFMT_DISTIMER_MASK;
- } else {
- delay |= (spicfg->c2tdelay << SPIDELAY_C2TDELAY_SHIFT)
- & SPIDELAY_C2TDELAY_MASK;
- delay |= (spicfg->t2cdelay << SPIDELAY_T2CDELAY_SHIFT)
- & SPIDELAY_T2CDELAY_MASK;
- }
-
- if (spi->mode & SPI_READY) {
- spifmt |= SPIFMT_WAITENA_MASK;
- delay |= (spicfg->t2edelay << SPIDELAY_T2EDELAY_SHIFT)
- & SPIDELAY_T2EDELAY_MASK;
- delay |= (spicfg->c2edelay << SPIDELAY_C2EDELAY_SHIFT)
- & SPIDELAY_C2EDELAY_MASK;
- }
-
- iowrite32(delay, dspi->base + SPIDELAY);
- }
-
- iowrite32(spifmt, dspi->base + SPIFMT0);
-
- 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 = 0;
- struct davinci_spi *dspi;
- struct davinci_spi_platform_data *pdata;
-
- dspi = spi_master_get_devdata(spi->master);
- pdata = dspi->pdata;
-
- /* if bits per word length is zero then set it default 8 */
- if (!spi->bits_per_word)
- spi->bits_per_word = 8;
-
- if (!(spi->mode & SPI_NO_CS)) {
- if ((pdata->chip_sel == NULL) ||
- (pdata->chip_sel[spi->chip_select] == SPI_INTERN_CS))
- set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select);
-
- }
-
- if (spi->mode & SPI_READY)
- set_io_bits(dspi->base + SPIPC0, SPIPC0_SPIENA_MASK);
-
- if (spi->mode & SPI_LOOP)
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK);
- else
- clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK);
-
- return retval;
-}
-
-static int davinci_spi_check_error(struct davinci_spi *dspi, int int_status)
-{
- struct device *sdev = dspi->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 (dspi->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_BUF_INIT_ACTIVE_MASK) {
- dev_dbg(sdev, "SPI Buffer Init Active\n");
- return -EBUSY;
- }
- }
-
- return 0;
-}
-
-/**
- * davinci_spi_process_events - check for and handle any SPI controller events
- * @dspi: the controller data
- *
- * This function will check the SPIFLG register and handle any events that are
- * detected there
- */
-static int davinci_spi_process_events(struct davinci_spi *dspi)
-{
- u32 buf, status, errors = 0, spidat1;
-
- buf = ioread32(dspi->base + SPIBUF);
-
- if (dspi->rcount > 0 && !(buf & SPIBUF_RXEMPTY_MASK)) {
- dspi->get_rx(buf & 0xFFFF, dspi);
- dspi->rcount--;
- }
-
- status = ioread32(dspi->base + SPIFLG);
-
- if (unlikely(status & SPIFLG_ERROR_MASK)) {
- errors = status & SPIFLG_ERROR_MASK;
- goto out;
- }
-
- if (dspi->wcount > 0 && !(buf & SPIBUF_TXFULL_MASK)) {
- spidat1 = ioread32(dspi->base + SPIDAT1);
- dspi->wcount--;
- spidat1 &= ~0xFFFF;
- spidat1 |= 0xFFFF & dspi->get_tx(dspi);
- iowrite32(spidat1, dspi->base + SPIDAT1);
- }
-
-out:
- return errors;
-}
-
-static void davinci_spi_dma_callback(unsigned lch, u16 status, void *data)
-{
- struct davinci_spi *dspi = data;
- struct davinci_spi_dma *dma = &dspi->dma;
-
- edma_stop(lch);
-
- if (status == DMA_COMPLETE) {
- if (lch == dma->rx_channel)
- dspi->rcount = 0;
- if (lch == dma->tx_channel)
- dspi->wcount = 0;
- }
-
- if ((!dspi->wcount && !dspi->rcount) || (status != DMA_COMPLETE))
- complete(&dspi->done);
-}
-
-/**
- * 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(struct spi_device *spi, struct spi_transfer *t)
-{
- struct davinci_spi *dspi;
- int data_type, ret;
- u32 tx_data, spidat1;
- u32 errors = 0;
- struct davinci_spi_config *spicfg;
- struct davinci_spi_platform_data *pdata;
- unsigned uninitialized_var(rx_buf_count);
- struct device *sdev;
-
- dspi = spi_master_get_devdata(spi->master);
- pdata = dspi->pdata;
- spicfg = (struct davinci_spi_config *)spi->controller_data;
- if (!spicfg)
- spicfg = &davinci_spi_default_cfg;
- sdev = dspi->bitbang.master->dev.parent;
-
- /* convert len to words based on bits_per_word */
- data_type = dspi->bytes_per_word[spi->chip_select];
-
- dspi->tx = t->tx_buf;
- dspi->rx = t->rx_buf;
- dspi->wcount = t->len / data_type;
- dspi->rcount = dspi->wcount;
-
- spidat1 = ioread32(dspi->base + SPIDAT1);
-
- clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK);
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
-
- INIT_COMPLETION(dspi->done);
-
- if (spicfg->io_type == SPI_IO_TYPE_INTR)
- set_io_bits(dspi->base + SPIINT, SPIINT_MASKINT);
-
- if (spicfg->io_type != SPI_IO_TYPE_DMA) {
- /* start the transfer */
- dspi->wcount--;
- tx_data = dspi->get_tx(dspi);
- spidat1 &= 0xFFFF0000;
- spidat1 |= tx_data & 0xFFFF;
- iowrite32(spidat1, dspi->base + SPIDAT1);
- } else {
- struct davinci_spi_dma *dma;
- unsigned long tx_reg, rx_reg;
- struct edmacc_param param;
- void *rx_buf;
- int b, c;
-
- dma = &dspi->dma;
-
- tx_reg = (unsigned long)dspi->pbase + SPIDAT1;
- rx_reg = (unsigned long)dspi->pbase + SPIBUF;
-
- /*
- * Transmit DMA setup
- *
- * If there is transmit data, map the transmit buffer, set it
- * as the source of data and set the source B index to data
- * size. If there is no transmit data, set the transmit register
- * as the source of data, and set the source B index to zero.
- *
- * The destination is always the transmit register itself. And
- * the destination never increments.
- */
-
- if (t->tx_buf) {
- t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf,
- t->len, DMA_TO_DEVICE);
- if (dma_mapping_error(&spi->dev, t->tx_dma)) {
- dev_dbg(sdev, "Unable to DMA map %d bytes"
- "TX buffer\n", t->len);
- return -ENOMEM;
- }
- }
-
- /*
- * If number of words is greater than 65535, then we need
- * to configure a 3 dimension transfer. Use the BCNTRLD
- * feature to allow for transfers that aren't even multiples
- * of 65535 (or any other possible b size) by first transferring
- * the remainder amount then grabbing the next N blocks of
- * 65535 words.
- */
-
- c = dspi->wcount / (SZ_64K - 1); /* N 65535 Blocks */
- b = dspi->wcount - c * (SZ_64K - 1); /* Remainder */
- if (b)
- c++;
- else
- b = SZ_64K - 1;
-
- param.opt = TCINTEN | EDMA_TCC(dma->tx_channel);
- param.src = t->tx_buf ? t->tx_dma : tx_reg;
- param.a_b_cnt = b << 16 | data_type;
- param.dst = tx_reg;
- param.src_dst_bidx = t->tx_buf ? data_type : 0;
- param.link_bcntrld = 0xffffffff;
- param.src_dst_cidx = t->tx_buf ? data_type : 0;
- param.ccnt = c;
- edma_write_slot(dma->tx_channel, &param);
- edma_link(dma->tx_channel, dma->dummy_param_slot);
-
- /*
- * Receive DMA setup
- *
- * If there is receive buffer, use it to receive data. If there
- * is none provided, use a temporary receive buffer. Set the
- * destination B index to 0 so effectively only one byte is used
- * in the temporary buffer (address does not increment).
- *
- * The source of receive data is the receive data register. The
- * source address never increments.
- */
-
- if (t->rx_buf) {
- rx_buf = t->rx_buf;
- rx_buf_count = t->len;
- } else {
- rx_buf = dspi->rx_tmp_buf;
- rx_buf_count = sizeof(dspi->rx_tmp_buf);
- }
-
- t->rx_dma = dma_map_single(&spi->dev, rx_buf, 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",
- rx_buf_count);
- if (t->tx_buf)
- dma_unmap_single(NULL, t->tx_dma, t->len,
- DMA_TO_DEVICE);
- return -ENOMEM;
- }
-
- param.opt = TCINTEN | EDMA_TCC(dma->rx_channel);
- param.src = rx_reg;
- param.a_b_cnt = b << 16 | data_type;
- param.dst = t->rx_dma;
- param.src_dst_bidx = (t->rx_buf ? data_type : 0) << 16;
- param.link_bcntrld = 0xffffffff;
- param.src_dst_cidx = (t->rx_buf ? data_type : 0) << 16;
- param.ccnt = c;
- edma_write_slot(dma->rx_channel, &param);
-
- if (pdata->cshold_bug)
- iowrite16(spidat1 >> 16, dspi->base + SPIDAT1 + 2);
-
- edma_start(dma->rx_channel);
- edma_start(dma->tx_channel);
- set_io_bits(dspi->base + SPIINT, SPIINT_DMA_REQ_EN);
- }
-
- /* Wait for the transfer to complete */
- if (spicfg->io_type != SPI_IO_TYPE_POLL) {
- wait_for_completion_interruptible(&(dspi->done));
- } else {
- while (dspi->rcount > 0 || dspi->wcount > 0) {
- errors = davinci_spi_process_events(dspi);
- if (errors)
- break;
- cpu_relax();
- }
- }
-
- clear_io_bits(dspi->base + SPIINT, SPIINT_MASKALL);
- if (spicfg->io_type == SPI_IO_TYPE_DMA) {
-
- if (t->tx_buf)
- dma_unmap_single(NULL, t->tx_dma, t->len,
- DMA_TO_DEVICE);
-
- dma_unmap_single(NULL, t->rx_dma, rx_buf_count,
- DMA_FROM_DEVICE);
-
- clear_io_bits(dspi->base + SPIINT, SPIINT_DMA_REQ_EN);
- }
-
- clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK);
-
- /*
- * Check for bit error, desync error,parity error,timeout error and
- * receive overflow errors
- */
- if (errors) {
- ret = davinci_spi_check_error(dspi, errors);
- WARN(!ret, "%s: error reported but no error found!\n",
- dev_name(&spi->dev));
- return ret;
- }
-
- if (dspi->rcount != 0 || dspi->wcount != 0) {
- dev_err(sdev, "SPI data transfer error\n");
- return -EIO;
- }
-
- return t->len;
-}
-
-/**
- * davinci_spi_irq - Interrupt handler for SPI Master Controller
- * @irq: IRQ number for this SPI Master
- * @context_data: structure for SPI Master controller davinci_spi
- *
- * ISR will determine that interrupt arrives either for READ or WRITE command.
- * According to command it will do the appropriate action. It will check
- * transfer length and if it is not zero then dispatch transfer command again.
- * If transfer length is zero then it will indicate the COMPLETION so that
- * davinci_spi_bufs function can go ahead.
- */
-static irqreturn_t davinci_spi_irq(s32 irq, void *data)
-{
- struct davinci_spi *dspi = data;
- int status;
-
- status = davinci_spi_process_events(dspi);
- if (unlikely(status != 0))
- clear_io_bits(dspi->base + SPIINT, SPIINT_MASKINT);
-
- if ((!dspi->rcount && !dspi->wcount) || status)
- complete(&dspi->done);
-
- return IRQ_HANDLED;
-}
-
-static int davinci_spi_request_dma(struct davinci_spi *dspi)
-{
- int r;
- struct davinci_spi_dma *dma = &dspi->dma;
-
- r = edma_alloc_channel(dma->rx_channel, davinci_spi_dma_callback, dspi,
- dma->eventq);
- if (r < 0) {
- pr_err("Unable to request DMA channel for SPI RX\n");
- r = -EAGAIN;
- goto rx_dma_failed;
- }
-
- r = edma_alloc_channel(dma->tx_channel, davinci_spi_dma_callback, dspi,
- dma->eventq);
- if (r < 0) {
- pr_err("Unable to request DMA channel for SPI TX\n");
- r = -EAGAIN;
- goto tx_dma_failed;
- }
-
- r = edma_alloc_slot(EDMA_CTLR(dma->tx_channel), EDMA_SLOT_ANY);
- if (r < 0) {
- pr_err("Unable to request SPI TX DMA param slot\n");
- r = -EAGAIN;
- goto param_failed;
- }
- dma->dummy_param_slot = r;
- edma_link(dma->dummy_param_slot, dma->dummy_param_slot);
-
- return 0;
-param_failed:
- edma_free_channel(dma->tx_channel);
-tx_dma_failed:
- edma_free_channel(dma->rx_channel);
-rx_dma_failed:
- return r;
-}
-
-/**
- * davinci_spi_probe - probe function for SPI Master Controller
- * @pdev: platform_device structure which contains plateform specific data
- *
- * According to Linux Device Model this function will be invoked by Linux
- * with platform_device struct which contains the device specific info.
- * This function will map the SPI controller's memory, register IRQ,
- * Reset SPI controller and setting its registers to default value.
- * It will invoke spi_bitbang_start to create work queue so that client driver
- * can register transfer method to work queue.
- */
-static int davinci_spi_probe(struct platform_device *pdev)
-{
- struct spi_master *master;
- struct davinci_spi *dspi;
- 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;
- int i = 0, ret = 0;
- u32 spipc0;
-
- 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);
-
- dspi = spi_master_get_devdata(master);
- if (dspi == NULL) {
- ret = -ENOENT;
- goto free_master;
- }
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (r == NULL) {
- ret = -ENOENT;
- goto free_master;
- }
-
- dspi->pbase = r->start;
- dspi->pdata = pdata;
-
- mem = request_mem_region(r->start, resource_size(r), pdev->name);
- if (mem == NULL) {
- ret = -EBUSY;
- goto free_master;
- }
-
- dspi->base = ioremap(r->start, resource_size(r));
- if (dspi->base == NULL) {
- ret = -ENOMEM;
- goto release_region;
- }
-
- dspi->irq = platform_get_irq(pdev, 0);
- if (dspi->irq <= 0) {
- ret = -EINVAL;
- goto unmap_io;
- }
-
- ret = request_irq(dspi->irq, davinci_spi_irq, 0, dev_name(&pdev->dev),
- dspi);
- if (ret)
- goto unmap_io;
-
- dspi->bitbang.master = spi_master_get(master);
- if (dspi->bitbang.master == NULL) {
- ret = -ENODEV;
- goto irq_free;
- }
-
- dspi->clk = clk_get(&pdev->dev, NULL);
- if (IS_ERR(dspi->clk)) {
- ret = -ENODEV;
- goto put_master;
- }
- clk_enable(dspi->clk);
-
- master->bus_num = pdev->id;
- master->num_chipselect = pdata->num_chipselect;
- master->setup = davinci_spi_setup;
-
- dspi->bitbang.chipselect = davinci_spi_chipselect;
- dspi->bitbang.setup_transfer = davinci_spi_setup_transfer;
-
- dspi->version = pdata->version;
-
- dspi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP;
- if (dspi->version == SPI_VERSION_2)
- dspi->bitbang.flags |= SPI_READY;
-
- 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;
-
- dspi->bitbang.txrx_bufs = davinci_spi_bufs;
- if (dma_rx_chan != SPI_NO_RESOURCE &&
- dma_tx_chan != SPI_NO_RESOURCE) {
- dspi->dma.rx_channel = dma_rx_chan;
- dspi->dma.tx_channel = dma_tx_chan;
- dspi->dma.eventq = pdata->dma_event_q;
-
- ret = davinci_spi_request_dma(dspi);
- if (ret)
- goto free_clk;
-
- dev_info(&pdev->dev, "DMA: supported\n");
- dev_info(&pdev->dev, "DMA: RX channel: %d, TX channel: %d, "
- "event queue: %d\n", dma_rx_chan, dma_tx_chan,
- pdata->dma_event_q);
- }
-
- dspi->get_rx = davinci_spi_rx_buf_u8;
- dspi->get_tx = davinci_spi_tx_buf_u8;
-
- init_completion(&dspi->done);
-
- /* Reset In/OUT SPI module */
- iowrite32(0, dspi->base + SPIGCR0);
- udelay(100);
- iowrite32(1, dspi->base + SPIGCR0);
-
- /* Set up SPIPC0. CS and ENA init is done in davinci_spi_setup */
- spipc0 = SPIPC0_DIFUN_MASK | SPIPC0_DOFUN_MASK | SPIPC0_CLKFUN_MASK;
- iowrite32(spipc0, dspi->base + SPIPC0);
-
- /* initialize chip selects */
- if (pdata->chip_sel) {
- for (i = 0; i < pdata->num_chipselect; i++) {
- if (pdata->chip_sel[i] != SPI_INTERN_CS)
- gpio_direction_output(pdata->chip_sel[i], 1);
- }
- }
-
- if (pdata->intr_line)
- iowrite32(SPI_INTLVL_1, dspi->base + SPILVL);
- else
- iowrite32(SPI_INTLVL_0, dspi->base + SPILVL);
-
- iowrite32(CS_DEFAULT, dspi->base + SPIDEF);
-
- /* master mode default */
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_CLKMOD_MASK);
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_MASTER_MASK);
- set_io_bits(dspi->base + SPIGCR1, SPIGCR1_POWERDOWN_MASK);
-
- ret = spi_bitbang_start(&dspi->bitbang);
- if (ret)
- goto free_dma;
-
- dev_info(&pdev->dev, "Controller at 0x%p\n", dspi->base);
-
- return ret;
-
-free_dma:
- edma_free_channel(dspi->dma.tx_channel);
- edma_free_channel(dspi->dma.rx_channel);
- edma_free_slot(dspi->dma.dummy_param_slot);
-free_clk:
- clk_disable(dspi->clk);
- clk_put(dspi->clk);
-put_master:
- spi_master_put(master);
-irq_free:
- free_irq(dspi->irq, dspi);
-unmap_io:
- iounmap(dspi->base);
-release_region:
- release_mem_region(dspi->pbase, resource_size(r));
-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 *dspi;
- struct spi_master *master;
- struct resource *r;
-
- master = dev_get_drvdata(&pdev->dev);
- dspi = spi_master_get_devdata(master);
-
- spi_bitbang_stop(&dspi->bitbang);
-
- clk_disable(dspi->clk);
- clk_put(dspi->clk);
- spi_master_put(master);
- free_irq(dspi->irq, dspi);
- iounmap(dspi->base);
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(dspi->pbase, resource_size(r));
-
- return 0;
-}
-
-static struct platform_driver davinci_spi_driver = {
- .driver = {
- .name = "spi_davinci",
- .owner = THIS_MODULE,
- },
- .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");