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![Linus Torvalds](/assets/img/avatar_default.png)
* 'spi/next' of git://git.secretlab.ca/git/linux-2.6: (34 commits) spi/dw_spi: move dw_spi.h into drivers/spi spi/dw_spi: Fix missing header gpio/langwell: Clear edge bit before handling gpio/langwell: Simplify demux loop gpio/langwell: Convert irq name space gpio/langwell: Fix broken irq_eoi change. gpio; Make Intel chipset gpio drivers depend on x86 gpio/cs5535-gpio: Fix section mismatch spi/rtc-{ds1390,ds3234,m41t94}: Use spi_get_drvdata() for SPI devices spi/davinci: Support DMA transfers larger than 65535 words spi/davinci: Use correct length parameter to dma_map_single calls gpio: Use __devexit at necessary places gpio: add MODULE_DEVICE_TABLE to pch_gpio and ml_ioh_gpio gpio/mcp23s08: support mcp23s17 variant of_mmc_spi: add card detect irq support spi/omap_mcspi: catch xfers of non-multiple SPI word size spi/omap_mcspi: Off-by-one error in finding the right divisor gpio/pca953x: Fix wrong pointer type spi/pl022: rid dangling labels spi: add support for SuperH SPI ...
1030 lines
26 KiB
C
1030 lines
26 KiB
C
/*
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* Copyright (C) 2009 Texas Instruments.
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* Copyright (C) 2010 EF Johnson Technologies
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/gpio.h>
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#include <linux/module.h>
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#include <linux/delay.h>
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#include <linux/platform_device.h>
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#include <linux/err.h>
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#include <linux/clk.h>
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#include <linux/dma-mapping.h>
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#include <linux/spi/spi.h>
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#include <linux/spi/spi_bitbang.h>
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#include <linux/slab.h>
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#include <mach/spi.h>
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#include <mach/edma.h>
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#define SPI_NO_RESOURCE ((resource_size_t)-1)
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#define SPI_MAX_CHIPSELECT 2
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#define CS_DEFAULT 0xFF
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#define SPIFMT_PHASE_MASK BIT(16)
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#define SPIFMT_POLARITY_MASK BIT(17)
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#define SPIFMT_DISTIMER_MASK BIT(18)
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#define SPIFMT_SHIFTDIR_MASK BIT(20)
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#define SPIFMT_WAITENA_MASK BIT(21)
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#define SPIFMT_PARITYENA_MASK BIT(22)
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#define SPIFMT_ODD_PARITY_MASK BIT(23)
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#define SPIFMT_WDELAY_MASK 0x3f000000u
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#define SPIFMT_WDELAY_SHIFT 24
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#define SPIFMT_PRESCALE_SHIFT 8
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/* SPIPC0 */
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#define SPIPC0_DIFUN_MASK BIT(11) /* MISO */
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#define SPIPC0_DOFUN_MASK BIT(10) /* MOSI */
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#define SPIPC0_CLKFUN_MASK BIT(9) /* CLK */
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#define SPIPC0_SPIENA_MASK BIT(8) /* nREADY */
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#define SPIINT_MASKALL 0x0101035F
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#define SPIINT_MASKINT 0x0000015F
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#define SPI_INTLVL_1 0x000001FF
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#define SPI_INTLVL_0 0x00000000
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/* SPIDAT1 (upper 16 bit defines) */
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#define SPIDAT1_CSHOLD_MASK BIT(12)
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/* SPIGCR1 */
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#define SPIGCR1_CLKMOD_MASK BIT(1)
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#define SPIGCR1_MASTER_MASK BIT(0)
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#define SPIGCR1_POWERDOWN_MASK BIT(8)
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#define SPIGCR1_LOOPBACK_MASK BIT(16)
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#define SPIGCR1_SPIENA_MASK BIT(24)
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/* SPIBUF */
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#define SPIBUF_TXFULL_MASK BIT(29)
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#define SPIBUF_RXEMPTY_MASK BIT(31)
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/* SPIDELAY */
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#define SPIDELAY_C2TDELAY_SHIFT 24
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#define SPIDELAY_C2TDELAY_MASK (0xFF << SPIDELAY_C2TDELAY_SHIFT)
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#define SPIDELAY_T2CDELAY_SHIFT 16
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#define SPIDELAY_T2CDELAY_MASK (0xFF << SPIDELAY_T2CDELAY_SHIFT)
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#define SPIDELAY_T2EDELAY_SHIFT 8
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#define SPIDELAY_T2EDELAY_MASK (0xFF << SPIDELAY_T2EDELAY_SHIFT)
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#define SPIDELAY_C2EDELAY_SHIFT 0
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#define SPIDELAY_C2EDELAY_MASK 0xFF
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/* Error Masks */
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#define SPIFLG_DLEN_ERR_MASK BIT(0)
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#define SPIFLG_TIMEOUT_MASK BIT(1)
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#define SPIFLG_PARERR_MASK BIT(2)
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#define SPIFLG_DESYNC_MASK BIT(3)
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#define SPIFLG_BITERR_MASK BIT(4)
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#define SPIFLG_OVRRUN_MASK BIT(6)
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#define SPIFLG_BUF_INIT_ACTIVE_MASK BIT(24)
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#define SPIFLG_ERROR_MASK (SPIFLG_DLEN_ERR_MASK \
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| SPIFLG_TIMEOUT_MASK | SPIFLG_PARERR_MASK \
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| SPIFLG_DESYNC_MASK | SPIFLG_BITERR_MASK \
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| SPIFLG_OVRRUN_MASK)
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#define SPIINT_DMA_REQ_EN BIT(16)
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/* SPI Controller registers */
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#define SPIGCR0 0x00
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#define SPIGCR1 0x04
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#define SPIINT 0x08
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#define SPILVL 0x0c
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#define SPIFLG 0x10
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#define SPIPC0 0x14
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#define SPIDAT1 0x3c
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#define SPIBUF 0x40
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#define SPIDELAY 0x48
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#define SPIDEF 0x4c
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#define SPIFMT0 0x50
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/* We have 2 DMA channels per CS, one for RX and one for TX */
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struct davinci_spi_dma {
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int tx_channel;
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int rx_channel;
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int dummy_param_slot;
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enum dma_event_q eventq;
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};
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/* SPI Controller driver's private data. */
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struct davinci_spi {
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struct spi_bitbang bitbang;
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struct clk *clk;
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u8 version;
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resource_size_t pbase;
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void __iomem *base;
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u32 irq;
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struct completion done;
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const void *tx;
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void *rx;
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#define SPI_TMP_BUFSZ (SMP_CACHE_BYTES + 1)
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u8 rx_tmp_buf[SPI_TMP_BUFSZ];
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int rcount;
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int wcount;
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struct davinci_spi_dma dma;
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struct davinci_spi_platform_data *pdata;
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void (*get_rx)(u32 rx_data, struct davinci_spi *);
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u32 (*get_tx)(struct davinci_spi *);
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u8 bytes_per_word[SPI_MAX_CHIPSELECT];
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};
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static struct davinci_spi_config davinci_spi_default_cfg;
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static void davinci_spi_rx_buf_u8(u32 data, struct davinci_spi *dspi)
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{
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if (dspi->rx) {
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u8 *rx = dspi->rx;
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*rx++ = (u8)data;
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dspi->rx = rx;
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}
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}
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static void davinci_spi_rx_buf_u16(u32 data, struct davinci_spi *dspi)
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{
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if (dspi->rx) {
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u16 *rx = dspi->rx;
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*rx++ = (u16)data;
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dspi->rx = rx;
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}
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}
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static u32 davinci_spi_tx_buf_u8(struct davinci_spi *dspi)
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{
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u32 data = 0;
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if (dspi->tx) {
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const u8 *tx = dspi->tx;
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data = *tx++;
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dspi->tx = tx;
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}
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return data;
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}
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static u32 davinci_spi_tx_buf_u16(struct davinci_spi *dspi)
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{
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u32 data = 0;
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if (dspi->tx) {
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const u16 *tx = dspi->tx;
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data = *tx++;
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dspi->tx = tx;
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}
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return data;
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}
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static inline void set_io_bits(void __iomem *addr, u32 bits)
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{
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u32 v = ioread32(addr);
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v |= bits;
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iowrite32(v, addr);
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}
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static inline void clear_io_bits(void __iomem *addr, u32 bits)
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{
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u32 v = ioread32(addr);
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v &= ~bits;
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iowrite32(v, addr);
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}
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/*
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* Interface to control the chip select signal
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*/
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static void davinci_spi_chipselect(struct spi_device *spi, int value)
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{
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struct davinci_spi *dspi;
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struct davinci_spi_platform_data *pdata;
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u8 chip_sel = spi->chip_select;
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u16 spidat1 = CS_DEFAULT;
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bool gpio_chipsel = false;
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dspi = spi_master_get_devdata(spi->master);
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pdata = dspi->pdata;
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if (pdata->chip_sel && chip_sel < pdata->num_chipselect &&
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pdata->chip_sel[chip_sel] != SPI_INTERN_CS)
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gpio_chipsel = true;
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/*
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* Board specific chip select logic decides the polarity and cs
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* line for the controller
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*/
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if (gpio_chipsel) {
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if (value == BITBANG_CS_ACTIVE)
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gpio_set_value(pdata->chip_sel[chip_sel], 0);
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else
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gpio_set_value(pdata->chip_sel[chip_sel], 1);
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} else {
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if (value == BITBANG_CS_ACTIVE) {
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spidat1 |= SPIDAT1_CSHOLD_MASK;
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spidat1 &= ~(0x1 << chip_sel);
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}
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iowrite16(spidat1, dspi->base + SPIDAT1 + 2);
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}
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}
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/**
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* davinci_spi_get_prescale - Calculates the correct prescale value
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* @maxspeed_hz: the maximum rate the SPI clock can run at
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*
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* This function calculates the prescale value that generates a clock rate
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* less than or equal to the specified maximum.
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*
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* Returns: calculated prescale - 1 for easy programming into SPI registers
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* or negative error number if valid prescalar cannot be updated.
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*/
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static inline int davinci_spi_get_prescale(struct davinci_spi *dspi,
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u32 max_speed_hz)
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{
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int ret;
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ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz);
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if (ret < 3 || ret > 256)
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return -EINVAL;
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return ret - 1;
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}
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/**
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* davinci_spi_setup_transfer - This functions will determine transfer method
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* @spi: spi device on which data transfer to be done
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* @t: spi transfer in which transfer info is filled
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*
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* This function determines data transfer method (8/16/32 bit transfer).
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* It will also set the SPI Clock Control register according to
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* SPI slave device freq.
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*/
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static int davinci_spi_setup_transfer(struct spi_device *spi,
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struct spi_transfer *t)
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{
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struct davinci_spi *dspi;
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struct davinci_spi_config *spicfg;
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u8 bits_per_word = 0;
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u32 hz = 0, spifmt = 0, prescale = 0;
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dspi = spi_master_get_devdata(spi->master);
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spicfg = (struct davinci_spi_config *)spi->controller_data;
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if (!spicfg)
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spicfg = &davinci_spi_default_cfg;
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if (t) {
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bits_per_word = t->bits_per_word;
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hz = t->speed_hz;
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}
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/* if bits_per_word is not set then set it default */
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if (!bits_per_word)
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bits_per_word = spi->bits_per_word;
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/*
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* Assign function pointer to appropriate transfer method
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* 8bit, 16bit or 32bit transfer
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*/
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if (bits_per_word <= 8 && bits_per_word >= 2) {
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dspi->get_rx = davinci_spi_rx_buf_u8;
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dspi->get_tx = davinci_spi_tx_buf_u8;
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dspi->bytes_per_word[spi->chip_select] = 1;
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} else if (bits_per_word <= 16 && bits_per_word >= 2) {
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dspi->get_rx = davinci_spi_rx_buf_u16;
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dspi->get_tx = davinci_spi_tx_buf_u16;
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dspi->bytes_per_word[spi->chip_select] = 2;
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} else
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return -EINVAL;
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if (!hz)
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hz = spi->max_speed_hz;
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/* Set up SPIFMTn register, unique to this chipselect. */
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prescale = davinci_spi_get_prescale(dspi, hz);
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if (prescale < 0)
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return prescale;
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spifmt = (prescale << SPIFMT_PRESCALE_SHIFT) | (bits_per_word & 0x1f);
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if (spi->mode & SPI_LSB_FIRST)
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spifmt |= SPIFMT_SHIFTDIR_MASK;
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if (spi->mode & SPI_CPOL)
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spifmt |= SPIFMT_POLARITY_MASK;
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if (!(spi->mode & SPI_CPHA))
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spifmt |= SPIFMT_PHASE_MASK;
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/*
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* Version 1 hardware supports two basic SPI modes:
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* - Standard SPI mode uses 4 pins, with chipselect
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* - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS)
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* (distinct from SPI_3WIRE, with just one data wire;
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* or similar variants without MOSI or without MISO)
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*
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* Version 2 hardware supports an optional handshaking signal,
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* so it can support two more modes:
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* - 5 pin SPI variant is standard SPI plus SPI_READY
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* - 4 pin with enable is (SPI_READY | SPI_NO_CS)
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*/
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if (dspi->version == SPI_VERSION_2) {
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u32 delay = 0;
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spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT)
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& SPIFMT_WDELAY_MASK);
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if (spicfg->odd_parity)
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spifmt |= SPIFMT_ODD_PARITY_MASK;
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if (spicfg->parity_enable)
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spifmt |= SPIFMT_PARITYENA_MASK;
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if (spicfg->timer_disable) {
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spifmt |= SPIFMT_DISTIMER_MASK;
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} else {
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delay |= (spicfg->c2tdelay << SPIDELAY_C2TDELAY_SHIFT)
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& SPIDELAY_C2TDELAY_MASK;
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delay |= (spicfg->t2cdelay << SPIDELAY_T2CDELAY_SHIFT)
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& SPIDELAY_T2CDELAY_MASK;
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}
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if (spi->mode & SPI_READY) {
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spifmt |= SPIFMT_WAITENA_MASK;
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delay |= (spicfg->t2edelay << SPIDELAY_T2EDELAY_SHIFT)
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& SPIDELAY_T2EDELAY_MASK;
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delay |= (spicfg->c2edelay << SPIDELAY_C2EDELAY_SHIFT)
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& SPIDELAY_C2EDELAY_MASK;
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}
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iowrite32(delay, dspi->base + SPIDELAY);
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}
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iowrite32(spifmt, dspi->base + SPIFMT0);
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return 0;
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}
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/**
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* davinci_spi_setup - This functions will set default transfer method
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* @spi: spi device on which data transfer to be done
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*
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* This functions sets the default transfer method.
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*/
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static int davinci_spi_setup(struct spi_device *spi)
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{
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int retval = 0;
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struct davinci_spi *dspi;
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struct davinci_spi_platform_data *pdata;
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dspi = spi_master_get_devdata(spi->master);
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pdata = dspi->pdata;
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/* if bits per word length is zero then set it default 8 */
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if (!spi->bits_per_word)
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spi->bits_per_word = 8;
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if (!(spi->mode & SPI_NO_CS)) {
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if ((pdata->chip_sel == NULL) ||
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(pdata->chip_sel[spi->chip_select] == SPI_INTERN_CS))
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set_io_bits(dspi->base + SPIPC0, 1 << spi->chip_select);
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}
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if (spi->mode & SPI_READY)
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set_io_bits(dspi->base + SPIPC0, SPIPC0_SPIENA_MASK);
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if (spi->mode & SPI_LOOP)
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set_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK);
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else
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clear_io_bits(dspi->base + SPIGCR1, SPIGCR1_LOOPBACK_MASK);
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return retval;
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}
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static int davinci_spi_check_error(struct davinci_spi *dspi, int int_status)
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{
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struct device *sdev = dspi->bitbang.master->dev.parent;
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if (int_status & SPIFLG_TIMEOUT_MASK) {
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dev_dbg(sdev, "SPI Time-out Error\n");
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return -ETIMEDOUT;
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}
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if (int_status & SPIFLG_DESYNC_MASK) {
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dev_dbg(sdev, "SPI Desynchronization Error\n");
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return -EIO;
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}
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if (int_status & SPIFLG_BITERR_MASK) {
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dev_dbg(sdev, "SPI Bit error\n");
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return -EIO;
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}
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if (dspi->version == SPI_VERSION_2) {
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if (int_status & SPIFLG_DLEN_ERR_MASK) {
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dev_dbg(sdev, "SPI Data Length Error\n");
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return -EIO;
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}
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if (int_status & SPIFLG_PARERR_MASK) {
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dev_dbg(sdev, "SPI Parity Error\n");
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return -EIO;
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}
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if (int_status & SPIFLG_OVRRUN_MASK) {
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dev_dbg(sdev, "SPI Data Overrun error\n");
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return -EIO;
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}
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if (int_status & SPIFLG_BUF_INIT_ACTIVE_MASK) {
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dev_dbg(sdev, "SPI Buffer Init Active\n");
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return -EBUSY;
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}
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}
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return 0;
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}
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/**
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* davinci_spi_process_events - check for and handle any SPI controller events
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* @dspi: the controller data
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|
*
|
|
* 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, ¶m);
|
|
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, ¶m);
|
|
|
|
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");
|