/* * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved. * Copyright (C) 2008 Juergen Beisert * * 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 * 51 Franklin Street, Fifth Floor * Boston, MA 02110-1301, USA. */ #include <linux/clk.h> #include <linux/completion.h> #include <linux/delay.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/gpio.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/irq.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/spi/spi.h> #include <linux/spi/spi_bitbang.h> #include <linux/types.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_gpio.h> #include <linux/platform_data/dma-imx.h> #include <linux/platform_data/spi-imx.h> #define DRIVER_NAME "spi_imx" #define MXC_CSPIRXDATA 0x00 #define MXC_CSPITXDATA 0x04 #define MXC_CSPICTRL 0x08 #define MXC_CSPIINT 0x0c #define MXC_RESET 0x1c /* generic defines to abstract from the different register layouts */ #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */ #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */ /* The maximum bytes that a sdma BD can transfer.*/ #define MAX_SDMA_BD_BYTES (1 << 15) struct spi_imx_config { unsigned int speed_hz; unsigned int bpw; }; enum spi_imx_devtype { IMX1_CSPI, IMX21_CSPI, IMX27_CSPI, IMX31_CSPI, IMX35_CSPI, /* CSPI on all i.mx except above */ IMX51_ECSPI, /* ECSPI on i.mx51 and later */ }; struct spi_imx_data; struct spi_imx_devtype_data { void (*intctrl)(struct spi_imx_data *, int); int (*config)(struct spi_device *, struct spi_imx_config *); void (*trigger)(struct spi_imx_data *); int (*rx_available)(struct spi_imx_data *); void (*reset)(struct spi_imx_data *); enum spi_imx_devtype devtype; }; struct spi_imx_data { struct spi_bitbang bitbang; struct device *dev; struct completion xfer_done; void __iomem *base; unsigned long base_phys; struct clk *clk_per; struct clk *clk_ipg; unsigned long spi_clk; unsigned int spi_bus_clk; unsigned int bytes_per_word; unsigned int count; void (*tx)(struct spi_imx_data *); void (*rx)(struct spi_imx_data *); void *rx_buf; const void *tx_buf; unsigned int txfifo; /* number of words pushed in tx FIFO */ /* DMA */ bool usedma; u32 wml; struct completion dma_rx_completion; struct completion dma_tx_completion; const struct spi_imx_devtype_data *devtype_data; }; static inline int is_imx27_cspi(struct spi_imx_data *d) { return d->devtype_data->devtype == IMX27_CSPI; } static inline int is_imx35_cspi(struct spi_imx_data *d) { return d->devtype_data->devtype == IMX35_CSPI; } static inline int is_imx51_ecspi(struct spi_imx_data *d) { return d->devtype_data->devtype == IMX51_ECSPI; } static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d) { return is_imx51_ecspi(d) ? 64 : 8; } #define MXC_SPI_BUF_RX(type) \ static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \ { \ unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \ \ if (spi_imx->rx_buf) { \ *(type *)spi_imx->rx_buf = val; \ spi_imx->rx_buf += sizeof(type); \ } \ } #define MXC_SPI_BUF_TX(type) \ static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \ { \ type val = 0; \ \ if (spi_imx->tx_buf) { \ val = *(type *)spi_imx->tx_buf; \ spi_imx->tx_buf += sizeof(type); \ } \ \ spi_imx->count -= sizeof(type); \ \ writel(val, spi_imx->base + MXC_CSPITXDATA); \ } MXC_SPI_BUF_RX(u8) MXC_SPI_BUF_TX(u8) MXC_SPI_BUF_RX(u16) MXC_SPI_BUF_TX(u16) MXC_SPI_BUF_RX(u32) MXC_SPI_BUF_TX(u32) /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set * (which is currently not the case in this driver) */ static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192, 256, 384, 512, 768, 1024}; /* MX21, MX27 */ static unsigned int spi_imx_clkdiv_1(unsigned int fin, unsigned int fspi, unsigned int max) { int i; for (i = 2; i < max; i++) if (fspi * mxc_clkdivs[i] >= fin) return i; return max; } /* MX1, MX31, MX35, MX51 CSPI */ static unsigned int spi_imx_clkdiv_2(unsigned int fin, unsigned int fspi) { int i, div = 4; for (i = 0; i < 7; i++) { if (fspi * div >= fin) return i; div <<= 1; } return 7; } static int spi_imx_bytes_per_word(const int bpw) { return DIV_ROUND_UP(bpw, BITS_PER_BYTE); } static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *transfer) { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); unsigned int bpw; if (!master->dma_rx) return false; if (!transfer) return false; bpw = transfer->bits_per_word; if (!bpw) bpw = spi->bits_per_word; bpw = spi_imx_bytes_per_word(bpw); if (bpw != 1 && bpw != 2 && bpw != 4) return false; if (transfer->len < spi_imx->wml * bpw) return false; if (transfer->len % (spi_imx->wml * bpw)) return false; return true; } #define MX51_ECSPI_CTRL 0x08 #define MX51_ECSPI_CTRL_ENABLE (1 << 0) #define MX51_ECSPI_CTRL_XCH (1 << 2) #define MX51_ECSPI_CTRL_SMC (1 << 3) #define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4) #define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8 #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12 #define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18) #define MX51_ECSPI_CTRL_BL_OFFSET 20 #define MX51_ECSPI_CONFIG 0x0c #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0)) #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4)) #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8)) #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12)) #define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20)) #define MX51_ECSPI_INT 0x10 #define MX51_ECSPI_INT_TEEN (1 << 0) #define MX51_ECSPI_INT_RREN (1 << 3) #define MX51_ECSPI_DMA 0x14 #define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f) #define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16) #define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24) #define MX51_ECSPI_DMA_TEDEN (1 << 7) #define MX51_ECSPI_DMA_RXDEN (1 << 23) #define MX51_ECSPI_DMA_RXTDEN (1 << 31) #define MX51_ECSPI_STAT 0x18 #define MX51_ECSPI_STAT_RR (1 << 3) #define MX51_ECSPI_TESTREG 0x20 #define MX51_ECSPI_TESTREG_LBC BIT(31) /* MX51 eCSPI */ static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx, unsigned int fspi, unsigned int *fres) { /* * there are two 4-bit dividers, the pre-divider divides by * $pre, the post-divider by 2^$post */ unsigned int pre, post; unsigned int fin = spi_imx->spi_clk; if (unlikely(fspi > fin)) return 0; post = fls(fin) - fls(fspi); if (fin > fspi << post) post++; /* now we have: (fin <= fspi << post) with post being minimal */ post = max(4U, post) - 4; if (unlikely(post > 0xf)) { dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n", fspi, fin); return 0xff; } pre = DIV_ROUND_UP(fin, fspi << post) - 1; dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n", __func__, fin, fspi, post, pre); /* Resulting frequency for the SCLK line. */ *fres = (fin / (pre + 1)) >> post; return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) | (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET); } static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable) { unsigned val = 0; if (enable & MXC_INT_TE) val |= MX51_ECSPI_INT_TEEN; if (enable & MXC_INT_RR) val |= MX51_ECSPI_INT_RREN; writel(val, spi_imx->base + MX51_ECSPI_INT); } static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx) { u32 reg; reg = readl(spi_imx->base + MX51_ECSPI_CTRL); reg |= MX51_ECSPI_CTRL_XCH; writel(reg, spi_imx->base + MX51_ECSPI_CTRL); } static int mx51_ecspi_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); u32 ctrl = MX51_ECSPI_CTRL_ENABLE; u32 clk = config->speed_hz, delay, reg; u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG); /* * The hardware seems to have a race condition when changing modes. The * current assumption is that the selection of the channel arrives * earlier in the hardware than the mode bits when they are written at * the same time. * So set master mode for all channels as we do not support slave mode. */ ctrl |= MX51_ECSPI_CTRL_MODE_MASK; /* set clock speed */ ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk); spi_imx->spi_bus_clk = clk; /* set chip select to use */ ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select); ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET; cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select); if (spi->mode & SPI_CPHA) cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select); else cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select); if (spi->mode & SPI_CPOL) { cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select); cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select); } else { cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select); cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select); } if (spi->mode & SPI_CS_HIGH) cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select); else cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select); if (spi_imx->usedma) ctrl |= MX51_ECSPI_CTRL_SMC; /* CTRL register always go first to bring out controller from reset */ writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); reg = readl(spi_imx->base + MX51_ECSPI_TESTREG); if (spi->mode & SPI_LOOP) reg |= MX51_ECSPI_TESTREG_LBC; else reg &= ~MX51_ECSPI_TESTREG_LBC; writel(reg, spi_imx->base + MX51_ECSPI_TESTREG); writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG); /* * Wait until the changes in the configuration register CONFIGREG * propagate into the hardware. It takes exactly one tick of the * SCLK clock, but we will wait two SCLK clock just to be sure. The * effect of the delay it takes for the hardware to apply changes * is noticable if the SCLK clock run very slow. In such a case, if * the polarity of SCLK should be inverted, the GPIO ChipSelect might * be asserted before the SCLK polarity changes, which would disrupt * the SPI communication as the device on the other end would consider * the change of SCLK polarity as a clock tick already. */ delay = (2 * 1000000) / clk; if (likely(delay < 10)) /* SCLK is faster than 100 kHz */ udelay(delay); else /* SCLK is _very_ slow */ usleep_range(delay, delay + 10); /* * Configure the DMA register: setup the watermark * and enable DMA request. */ writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) | MX51_ECSPI_DMA_TX_WML(spi_imx->wml) | MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) | MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN | MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA); return 0; } static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR; } static void mx51_ecspi_reset(struct spi_imx_data *spi_imx) { /* drain receive buffer */ while (mx51_ecspi_rx_available(spi_imx)) readl(spi_imx->base + MXC_CSPIRXDATA); } #define MX31_INTREG_TEEN (1 << 0) #define MX31_INTREG_RREN (1 << 3) #define MX31_CSPICTRL_ENABLE (1 << 0) #define MX31_CSPICTRL_MASTER (1 << 1) #define MX31_CSPICTRL_XCH (1 << 2) #define MX31_CSPICTRL_POL (1 << 4) #define MX31_CSPICTRL_PHA (1 << 5) #define MX31_CSPICTRL_SSCTL (1 << 6) #define MX31_CSPICTRL_SSPOL (1 << 7) #define MX31_CSPICTRL_BC_SHIFT 8 #define MX35_CSPICTRL_BL_SHIFT 20 #define MX31_CSPICTRL_CS_SHIFT 24 #define MX35_CSPICTRL_CS_SHIFT 12 #define MX31_CSPICTRL_DR_SHIFT 16 #define MX31_CSPISTATUS 0x14 #define MX31_STATUS_RR (1 << 3) /* These functions also work for the i.MX35, but be aware that * the i.MX35 has a slightly different register layout for bits * we do not use here. */ static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable) { unsigned int val = 0; if (enable & MXC_INT_TE) val |= MX31_INTREG_TEEN; if (enable & MXC_INT_RR) val |= MX31_INTREG_RREN; writel(val, spi_imx->base + MXC_CSPIINT); } static void mx31_trigger(struct spi_imx_data *spi_imx) { unsigned int reg; reg = readl(spi_imx->base + MXC_CSPICTRL); reg |= MX31_CSPICTRL_XCH; writel(reg, spi_imx->base + MXC_CSPICTRL); } static int mx31_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER; reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << MX31_CSPICTRL_DR_SHIFT; if (is_imx35_cspi(spi_imx)) { reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT; reg |= MX31_CSPICTRL_SSCTL; } else { reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT; } if (spi->mode & SPI_CPHA) reg |= MX31_CSPICTRL_PHA; if (spi->mode & SPI_CPOL) reg |= MX31_CSPICTRL_POL; if (spi->mode & SPI_CS_HIGH) reg |= MX31_CSPICTRL_SSPOL; if (spi->cs_gpio < 0) reg |= (spi->cs_gpio + 32) << (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT : MX31_CSPICTRL_CS_SHIFT); writel(reg, spi_imx->base + MXC_CSPICTRL); return 0; } static int mx31_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR; } static void mx31_reset(struct spi_imx_data *spi_imx) { /* drain receive buffer */ while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR) readl(spi_imx->base + MXC_CSPIRXDATA); } #define MX21_INTREG_RR (1 << 4) #define MX21_INTREG_TEEN (1 << 9) #define MX21_INTREG_RREN (1 << 13) #define MX21_CSPICTRL_POL (1 << 5) #define MX21_CSPICTRL_PHA (1 << 6) #define MX21_CSPICTRL_SSPOL (1 << 8) #define MX21_CSPICTRL_XCH (1 << 9) #define MX21_CSPICTRL_ENABLE (1 << 10) #define MX21_CSPICTRL_MASTER (1 << 11) #define MX21_CSPICTRL_DR_SHIFT 14 #define MX21_CSPICTRL_CS_SHIFT 19 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable) { unsigned int val = 0; if (enable & MXC_INT_TE) val |= MX21_INTREG_TEEN; if (enable & MXC_INT_RR) val |= MX21_INTREG_RREN; writel(val, spi_imx->base + MXC_CSPIINT); } static void mx21_trigger(struct spi_imx_data *spi_imx) { unsigned int reg; reg = readl(spi_imx->base + MXC_CSPICTRL); reg |= MX21_CSPICTRL_XCH; writel(reg, spi_imx->base + MXC_CSPICTRL); } static int mx21_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER; unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18; reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) << MX21_CSPICTRL_DR_SHIFT; reg |= config->bpw - 1; if (spi->mode & SPI_CPHA) reg |= MX21_CSPICTRL_PHA; if (spi->mode & SPI_CPOL) reg |= MX21_CSPICTRL_POL; if (spi->mode & SPI_CS_HIGH) reg |= MX21_CSPICTRL_SSPOL; if (spi->cs_gpio < 0) reg |= (spi->cs_gpio + 32) << MX21_CSPICTRL_CS_SHIFT; writel(reg, spi_imx->base + MXC_CSPICTRL); return 0; } static int mx21_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR; } static void mx21_reset(struct spi_imx_data *spi_imx) { writel(1, spi_imx->base + MXC_RESET); } #define MX1_INTREG_RR (1 << 3) #define MX1_INTREG_TEEN (1 << 8) #define MX1_INTREG_RREN (1 << 11) #define MX1_CSPICTRL_POL (1 << 4) #define MX1_CSPICTRL_PHA (1 << 5) #define MX1_CSPICTRL_XCH (1 << 8) #define MX1_CSPICTRL_ENABLE (1 << 9) #define MX1_CSPICTRL_MASTER (1 << 10) #define MX1_CSPICTRL_DR_SHIFT 13 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable) { unsigned int val = 0; if (enable & MXC_INT_TE) val |= MX1_INTREG_TEEN; if (enable & MXC_INT_RR) val |= MX1_INTREG_RREN; writel(val, spi_imx->base + MXC_CSPIINT); } static void mx1_trigger(struct spi_imx_data *spi_imx) { unsigned int reg; reg = readl(spi_imx->base + MXC_CSPICTRL); reg |= MX1_CSPICTRL_XCH; writel(reg, spi_imx->base + MXC_CSPICTRL); } static int mx1_config(struct spi_device *spi, struct spi_imx_config *config) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER; reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) << MX1_CSPICTRL_DR_SHIFT; reg |= config->bpw - 1; if (spi->mode & SPI_CPHA) reg |= MX1_CSPICTRL_PHA; if (spi->mode & SPI_CPOL) reg |= MX1_CSPICTRL_POL; writel(reg, spi_imx->base + MXC_CSPICTRL); return 0; } static int mx1_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR; } static void mx1_reset(struct spi_imx_data *spi_imx) { writel(1, spi_imx->base + MXC_RESET); } static struct spi_imx_devtype_data imx1_cspi_devtype_data = { .intctrl = mx1_intctrl, .config = mx1_config, .trigger = mx1_trigger, .rx_available = mx1_rx_available, .reset = mx1_reset, .devtype = IMX1_CSPI, }; static struct spi_imx_devtype_data imx21_cspi_devtype_data = { .intctrl = mx21_intctrl, .config = mx21_config, .trigger = mx21_trigger, .rx_available = mx21_rx_available, .reset = mx21_reset, .devtype = IMX21_CSPI, }; static struct spi_imx_devtype_data imx27_cspi_devtype_data = { /* i.mx27 cspi shares the functions with i.mx21 one */ .intctrl = mx21_intctrl, .config = mx21_config, .trigger = mx21_trigger, .rx_available = mx21_rx_available, .reset = mx21_reset, .devtype = IMX27_CSPI, }; static struct spi_imx_devtype_data imx31_cspi_devtype_data = { .intctrl = mx31_intctrl, .config = mx31_config, .trigger = mx31_trigger, .rx_available = mx31_rx_available, .reset = mx31_reset, .devtype = IMX31_CSPI, }; static struct spi_imx_devtype_data imx35_cspi_devtype_data = { /* i.mx35 and later cspi shares the functions with i.mx31 one */ .intctrl = mx31_intctrl, .config = mx31_config, .trigger = mx31_trigger, .rx_available = mx31_rx_available, .reset = mx31_reset, .devtype = IMX35_CSPI, }; static struct spi_imx_devtype_data imx51_ecspi_devtype_data = { .intctrl = mx51_ecspi_intctrl, .config = mx51_ecspi_config, .trigger = mx51_ecspi_trigger, .rx_available = mx51_ecspi_rx_available, .reset = mx51_ecspi_reset, .devtype = IMX51_ECSPI, }; static const struct platform_device_id spi_imx_devtype[] = { { .name = "imx1-cspi", .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data, }, { .name = "imx21-cspi", .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data, }, { .name = "imx27-cspi", .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data, }, { .name = "imx31-cspi", .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data, }, { .name = "imx35-cspi", .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data, }, { .name = "imx51-ecspi", .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data, }, { /* sentinel */ } }; static const struct of_device_id spi_imx_dt_ids[] = { { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, }, { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, }, { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, }, { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, }, { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, }, { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, spi_imx_dt_ids); static void spi_imx_chipselect(struct spi_device *spi, int is_active) { int active = is_active != BITBANG_CS_INACTIVE; int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH); if (!gpio_is_valid(spi->cs_gpio)) return; gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active); } static void spi_imx_push(struct spi_imx_data *spi_imx) { while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) { if (!spi_imx->count) break; spi_imx->tx(spi_imx); spi_imx->txfifo++; } spi_imx->devtype_data->trigger(spi_imx); } static irqreturn_t spi_imx_isr(int irq, void *dev_id) { struct spi_imx_data *spi_imx = dev_id; while (spi_imx->devtype_data->rx_available(spi_imx)) { spi_imx->rx(spi_imx); spi_imx->txfifo--; } if (spi_imx->count) { spi_imx_push(spi_imx); return IRQ_HANDLED; } if (spi_imx->txfifo) { /* No data left to push, but still waiting for rx data, * enable receive data available interrupt. */ spi_imx->devtype_data->intctrl( spi_imx, MXC_INT_RR); return IRQ_HANDLED; } spi_imx->devtype_data->intctrl(spi_imx, 0); complete(&spi_imx->xfer_done); return IRQ_HANDLED; } static int spi_imx_dma_configure(struct spi_master *master, int bytes_per_word) { int ret; enum dma_slave_buswidth buswidth; struct dma_slave_config rx = {}, tx = {}; struct spi_imx_data *spi_imx = spi_master_get_devdata(master); if (bytes_per_word == spi_imx->bytes_per_word) /* Same as last time */ return 0; switch (bytes_per_word) { case 4: buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; break; case 2: buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; break; case 1: buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; break; default: return -EINVAL; } tx.direction = DMA_MEM_TO_DEV; tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA; tx.dst_addr_width = buswidth; tx.dst_maxburst = spi_imx->wml; ret = dmaengine_slave_config(master->dma_tx, &tx); if (ret) { dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret); return ret; } rx.direction = DMA_DEV_TO_MEM; rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA; rx.src_addr_width = buswidth; rx.src_maxburst = spi_imx->wml; ret = dmaengine_slave_config(master->dma_rx, &rx); if (ret) { dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret); return ret; } spi_imx->bytes_per_word = bytes_per_word; return 0; } static int spi_imx_setupxfer(struct spi_device *spi, struct spi_transfer *t) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); struct spi_imx_config config; int ret; config.bpw = t ? t->bits_per_word : spi->bits_per_word; config.speed_hz = t ? t->speed_hz : spi->max_speed_hz; if (!config.speed_hz) config.speed_hz = spi->max_speed_hz; if (!config.bpw) config.bpw = spi->bits_per_word; /* Initialize the functions for transfer */ if (config.bpw <= 8) { spi_imx->rx = spi_imx_buf_rx_u8; spi_imx->tx = spi_imx_buf_tx_u8; } else if (config.bpw <= 16) { spi_imx->rx = spi_imx_buf_rx_u16; spi_imx->tx = spi_imx_buf_tx_u16; } else { spi_imx->rx = spi_imx_buf_rx_u32; spi_imx->tx = spi_imx_buf_tx_u32; } if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t)) spi_imx->usedma = 1; else spi_imx->usedma = 0; if (spi_imx->usedma) { ret = spi_imx_dma_configure(spi->master, spi_imx_bytes_per_word(config.bpw)); if (ret) return ret; } spi_imx->devtype_data->config(spi, &config); return 0; } static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx) { struct spi_master *master = spi_imx->bitbang.master; if (master->dma_rx) { dma_release_channel(master->dma_rx); master->dma_rx = NULL; } if (master->dma_tx) { dma_release_channel(master->dma_tx); master->dma_tx = NULL; } } static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, struct spi_master *master) { int ret; /* use pio mode for i.mx6dl chip TKT238285 */ if (of_machine_is_compatible("fsl,imx6dl")) return 0; spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2; /* Prepare for TX DMA: */ master->dma_tx = dma_request_slave_channel_reason(dev, "tx"); if (IS_ERR(master->dma_tx)) { ret = PTR_ERR(master->dma_tx); dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret); master->dma_tx = NULL; goto err; } /* Prepare for RX : */ master->dma_rx = dma_request_slave_channel_reason(dev, "rx"); if (IS_ERR(master->dma_rx)) { ret = PTR_ERR(master->dma_rx); dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret); master->dma_rx = NULL; goto err; } spi_imx_dma_configure(master, 1); init_completion(&spi_imx->dma_rx_completion); init_completion(&spi_imx->dma_tx_completion); master->can_dma = spi_imx_can_dma; master->max_dma_len = MAX_SDMA_BD_BYTES; spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX; return 0; err: spi_imx_sdma_exit(spi_imx); return ret; } static void spi_imx_dma_rx_callback(void *cookie) { struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie; complete(&spi_imx->dma_rx_completion); } static void spi_imx_dma_tx_callback(void *cookie) { struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie; complete(&spi_imx->dma_tx_completion); } static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size) { unsigned long timeout = 0; /* Time with actual data transfer and CS change delay related to HW */ timeout = (8 + 4) * size / spi_imx->spi_bus_clk; /* Add extra second for scheduler related activities */ timeout += 1; /* Double calculated timeout */ return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC); } static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, struct spi_transfer *transfer) { struct dma_async_tx_descriptor *desc_tx, *desc_rx; unsigned long transfer_timeout; unsigned long timeout; struct spi_master *master = spi_imx->bitbang.master; struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg; /* * The TX DMA setup starts the transfer, so make sure RX is configured * before TX. */ desc_rx = dmaengine_prep_slave_sg(master->dma_rx, rx->sgl, rx->nents, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_rx) return -EINVAL; desc_rx->callback = spi_imx_dma_rx_callback; desc_rx->callback_param = (void *)spi_imx; dmaengine_submit(desc_rx); reinit_completion(&spi_imx->dma_rx_completion); dma_async_issue_pending(master->dma_rx); desc_tx = dmaengine_prep_slave_sg(master->dma_tx, tx->sgl, tx->nents, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_tx) { dmaengine_terminate_all(master->dma_tx); return -EINVAL; } desc_tx->callback = spi_imx_dma_tx_callback; desc_tx->callback_param = (void *)spi_imx; dmaengine_submit(desc_tx); reinit_completion(&spi_imx->dma_tx_completion); dma_async_issue_pending(master->dma_tx); transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len); /* Wait SDMA to finish the data transfer.*/ timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion, transfer_timeout); if (!timeout) { dev_err(spi_imx->dev, "I/O Error in DMA TX\n"); dmaengine_terminate_all(master->dma_tx); dmaengine_terminate_all(master->dma_rx); return -ETIMEDOUT; } timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion, transfer_timeout); if (!timeout) { dev_err(&master->dev, "I/O Error in DMA RX\n"); spi_imx->devtype_data->reset(spi_imx); dmaengine_terminate_all(master->dma_rx); return -ETIMEDOUT; } return transfer->len; } static int spi_imx_pio_transfer(struct spi_device *spi, struct spi_transfer *transfer) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); unsigned long transfer_timeout; unsigned long timeout; spi_imx->tx_buf = transfer->tx_buf; spi_imx->rx_buf = transfer->rx_buf; spi_imx->count = transfer->len; spi_imx->txfifo = 0; reinit_completion(&spi_imx->xfer_done); spi_imx_push(spi_imx); spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE); transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len); timeout = wait_for_completion_timeout(&spi_imx->xfer_done, transfer_timeout); if (!timeout) { dev_err(&spi->dev, "I/O Error in PIO\n"); spi_imx->devtype_data->reset(spi_imx); return -ETIMEDOUT; } return transfer->len; } static int spi_imx_transfer(struct spi_device *spi, struct spi_transfer *transfer) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); if (spi_imx->usedma) return spi_imx_dma_transfer(spi_imx, transfer); else return spi_imx_pio_transfer(spi, transfer); } static int spi_imx_setup(struct spi_device *spi) { dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__, spi->mode, spi->bits_per_word, spi->max_speed_hz); if (gpio_is_valid(spi->cs_gpio)) gpio_direction_output(spi->cs_gpio, spi->mode & SPI_CS_HIGH ? 0 : 1); spi_imx_chipselect(spi, BITBANG_CS_INACTIVE); return 0; } static void spi_imx_cleanup(struct spi_device *spi) { } static int spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg) { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); int ret; ret = clk_enable(spi_imx->clk_per); if (ret) return ret; ret = clk_enable(spi_imx->clk_ipg); if (ret) { clk_disable(spi_imx->clk_per); return ret; } return 0; } static int spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg) { struct spi_imx_data *spi_imx = spi_master_get_devdata(master); clk_disable(spi_imx->clk_ipg); clk_disable(spi_imx->clk_per); return 0; } static int spi_imx_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; const struct of_device_id *of_id = of_match_device(spi_imx_dt_ids, &pdev->dev); struct spi_imx_master *mxc_platform_info = dev_get_platdata(&pdev->dev); struct spi_master *master; struct spi_imx_data *spi_imx; struct resource *res; int i, ret, irq; if (!np && !mxc_platform_info) { dev_err(&pdev->dev, "can't get the platform data\n"); return -EINVAL; } master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data)); if (!master) return -ENOMEM; platform_set_drvdata(pdev, master); master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); master->bus_num = np ? -1 : pdev->id; spi_imx = spi_master_get_devdata(master); spi_imx->bitbang.master = master; spi_imx->dev = &pdev->dev; spi_imx->devtype_data = of_id ? of_id->data : (struct spi_imx_devtype_data *)pdev->id_entry->driver_data; if (mxc_platform_info) { master->num_chipselect = mxc_platform_info->num_chipselect; master->cs_gpios = devm_kzalloc(&master->dev, sizeof(int) * master->num_chipselect, GFP_KERNEL); if (!master->cs_gpios) return -ENOMEM; for (i = 0; i < master->num_chipselect; i++) master->cs_gpios[i] = mxc_platform_info->chipselect[i]; } spi_imx->bitbang.chipselect = spi_imx_chipselect; spi_imx->bitbang.setup_transfer = spi_imx_setupxfer; spi_imx->bitbang.txrx_bufs = spi_imx_transfer; spi_imx->bitbang.master->setup = spi_imx_setup; spi_imx->bitbang.master->cleanup = spi_imx_cleanup; spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message; spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message; spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; if (is_imx51_ecspi(spi_imx)) spi_imx->bitbang.master->mode_bits |= SPI_LOOP; init_completion(&spi_imx->xfer_done); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); spi_imx->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(spi_imx->base)) { ret = PTR_ERR(spi_imx->base); goto out_master_put; } spi_imx->base_phys = res->start; irq = platform_get_irq(pdev, 0); if (irq < 0) { ret = irq; goto out_master_put; } ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0, dev_name(&pdev->dev), spi_imx); if (ret) { dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret); goto out_master_put; } spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); if (IS_ERR(spi_imx->clk_ipg)) { ret = PTR_ERR(spi_imx->clk_ipg); goto out_master_put; } spi_imx->clk_per = devm_clk_get(&pdev->dev, "per"); if (IS_ERR(spi_imx->clk_per)) { ret = PTR_ERR(spi_imx->clk_per); goto out_master_put; } ret = clk_prepare_enable(spi_imx->clk_per); if (ret) goto out_master_put; ret = clk_prepare_enable(spi_imx->clk_ipg); if (ret) goto out_put_per; spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per); /* * Only validated on i.mx6 now, can remove the constrain if validated on * other chips. */ if (is_imx51_ecspi(spi_imx)) { ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master); if (ret == -EPROBE_DEFER) goto out_clk_put; if (ret < 0) dev_err(&pdev->dev, "dma setup error %d, use pio\n", ret); } spi_imx->devtype_data->reset(spi_imx); spi_imx->devtype_data->intctrl(spi_imx, 0); master->dev.of_node = pdev->dev.of_node; ret = spi_bitbang_start(&spi_imx->bitbang); if (ret) { dev_err(&pdev->dev, "bitbang start failed with %d\n", ret); goto out_clk_put; } for (i = 0; i < master->num_chipselect; i++) { if (!gpio_is_valid(master->cs_gpios[i])) continue; ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i], DRIVER_NAME); if (ret) { dev_err(&pdev->dev, "Can't get CS GPIO %i\n", master->cs_gpios[i]); goto out_clk_put; } } dev_info(&pdev->dev, "probed\n"); clk_disable(spi_imx->clk_ipg); clk_disable(spi_imx->clk_per); return ret; out_clk_put: clk_disable_unprepare(spi_imx->clk_ipg); out_put_per: clk_disable_unprepare(spi_imx->clk_per); out_master_put: spi_master_put(master); return ret; } static int spi_imx_remove(struct platform_device *pdev) { struct spi_master *master = platform_get_drvdata(pdev); struct spi_imx_data *spi_imx = spi_master_get_devdata(master); spi_bitbang_stop(&spi_imx->bitbang); writel(0, spi_imx->base + MXC_CSPICTRL); clk_unprepare(spi_imx->clk_ipg); clk_unprepare(spi_imx->clk_per); spi_imx_sdma_exit(spi_imx); spi_master_put(master); return 0; } static struct platform_driver spi_imx_driver = { .driver = { .name = DRIVER_NAME, .of_match_table = spi_imx_dt_ids, }, .id_table = spi_imx_devtype, .probe = spi_imx_probe, .remove = spi_imx_remove, }; module_platform_driver(spi_imx_driver); MODULE_DESCRIPTION("SPI Master Controller driver"); MODULE_AUTHOR("Sascha Hauer, Pengutronix"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DRIVER_NAME);