/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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) #define IMX_DMA_TIMEOUT (msecs_to_jiffies(3000)) struct spi_imx_config { unsigned int speed_hz; unsigned int bpw; unsigned int mode; u8 cs; }; 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_imx_data *, 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 completion xfer_done; void __iomem *base; struct clk *clk_per; struct clk *clk_ipg; unsigned long spi_clk; 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 */ unsigned int dma_is_inited; unsigned int dma_finished; bool usedma; u32 wml; struct completion dma_rx_completion; struct completion dma_tx_completion; const struct spi_imx_devtype_data *devtype_data; int chipselect[0]; }; 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 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); if (spi_imx->dma_is_inited && transfer->len > spi_imx->wml * sizeof(u32)) return true; return false; } #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_OFFSET 0 #define MX51_ECSPI_DMA_TX_WML_MASK 0x3F #define MX51_ECSPI_DMA_RX_WML_OFFSET 16 #define MX51_ECSPI_DMA_RX_WML_MASK (0x3F << 16) #define MX51_ECSPI_DMA_RXT_WML_OFFSET 24 #define MX51_ECSPI_DMA_RXT_WML_MASK (0x3F << 24) #define MX51_ECSPI_DMA_TEDEN_OFFSET 7 #define MX51_ECSPI_DMA_RXDEN_OFFSET 23 #define MX51_ECSPI_DMA_RXTDEN_OFFSET 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(unsigned int fin, 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; 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)) { pr_err("%s: cannot set clock freq: %u (base freq: %u)\n", __func__, fspi, fin); return 0xff; } pre = DIV_ROUND_UP(fin, fspi << post) - 1; pr_debug("%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 __maybe_unused 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 __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx) { u32 reg = readl(spi_imx->base + MX51_ECSPI_CTRL); if (!spi_imx->usedma) reg |= MX51_ECSPI_CTRL_XCH; else if (!spi_imx->dma_finished) reg |= MX51_ECSPI_CTRL_SMC; else reg &= ~MX51_ECSPI_CTRL_SMC; writel(reg, spi_imx->base + MX51_ECSPI_CTRL); } static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx, struct spi_imx_config *config) { u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0; u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg; u32 clk = config->speed_hz, delay, reg; /* * 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->spi_clk, config->speed_hz, &clk); /* set chip select to use */ ctrl |= MX51_ECSPI_CTRL_CS(config->cs); ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET; cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs); if (config->mode & SPI_CPHA) cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs); else cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(config->cs); if (config->mode & SPI_CPOL) { cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs); cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs); } else { cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(config->cs); cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(config->cs); } if (config->mode & SPI_CS_HIGH) cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs); else cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(config->cs); reg = readl(spi_imx->base + MX51_ECSPI_TESTREG); if (config->mode & SPI_LOOP) reg |= MX51_ECSPI_TESTREG_LBC; else reg &= ~MX51_ECSPI_TESTREG_LBC; writel(reg, spi_imx->base + MX51_ECSPI_TESTREG); writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); 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. */ if (spi_imx->dma_is_inited) { dma = readl(spi_imx->base + MX51_ECSPI_DMA); rx_wml_cfg = spi_imx->wml << MX51_ECSPI_DMA_RX_WML_OFFSET; tx_wml_cfg = spi_imx->wml << MX51_ECSPI_DMA_TX_WML_OFFSET; rxt_wml_cfg = spi_imx->wml << MX51_ECSPI_DMA_RXT_WML_OFFSET; dma = (dma & ~MX51_ECSPI_DMA_TX_WML_MASK & ~MX51_ECSPI_DMA_RX_WML_MASK & ~MX51_ECSPI_DMA_RXT_WML_MASK) | rx_wml_cfg | tx_wml_cfg | rxt_wml_cfg |(1 << MX51_ECSPI_DMA_TEDEN_OFFSET) |(1 << MX51_ECSPI_DMA_RXDEN_OFFSET) |(1 << MX51_ECSPI_DMA_RXTDEN_OFFSET); writel(dma, spi_imx->base + MX51_ECSPI_DMA); } return 0; } static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR; } static void __maybe_unused 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 __maybe_unused 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 __maybe_unused 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 __maybe_unused mx31_config(struct spi_imx_data *spi_imx, struct spi_imx_config *config) { unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER; int cs = spi_imx->chipselect[config->cs]; 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 (config->mode & SPI_CPHA) reg |= MX31_CSPICTRL_PHA; if (config->mode & SPI_CPOL) reg |= MX31_CSPICTRL_POL; if (config->mode & SPI_CS_HIGH) reg |= MX31_CSPICTRL_SSPOL; if (cs < 0) reg |= (cs + 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 __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR; } static void __maybe_unused 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 __maybe_unused 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 __maybe_unused 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 __maybe_unused mx21_config(struct spi_imx_data *spi_imx, struct spi_imx_config *config) { unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER; int cs = spi_imx->chipselect[config->cs]; 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 (config->mode & SPI_CPHA) reg |= MX21_CSPICTRL_PHA; if (config->mode & SPI_CPOL) reg |= MX21_CSPICTRL_POL; if (config->mode & SPI_CS_HIGH) reg |= MX21_CSPICTRL_SSPOL; if (cs < 0) reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT; writel(reg, spi_imx->base + MXC_CSPICTRL); return 0; } static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR; } static void __maybe_unused 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 __maybe_unused 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 __maybe_unused 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 __maybe_unused mx1_config(struct spi_imx_data *spi_imx, struct spi_imx_config *config) { 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 (config->mode & SPI_CPHA) reg |= MX1_CSPICTRL_PHA; if (config->mode & SPI_CPOL) reg |= MX1_CSPICTRL_POL; writel(reg, spi_imx->base + MXC_CSPICTRL); return 0; } static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx) { return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR; } static void __maybe_unused 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) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); int gpio = spi_imx->chipselect[spi->chip_select]; int active = is_active != BITBANG_CS_INACTIVE; int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH); if (!gpio_is_valid(gpio)) return; gpio_set_value(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_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; config.bpw = t ? t->bits_per_word : spi->bits_per_word; config.speed_hz = t ? t->speed_hz : spi->max_speed_hz; config.mode = spi->mode; config.cs = spi->chip_select; 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; } spi_imx->devtype_data->config(spi_imx, &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; } spi_imx->dma_is_inited = 0; } static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, struct spi_master *master, const struct resource *res) { struct dma_slave_config slave_config = {}; 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(dev, "tx"); if (!master->dma_tx) { dev_err(dev, "cannot get the TX DMA channel!\n"); ret = -EINVAL; goto err; } slave_config.direction = DMA_MEM_TO_DEV; slave_config.dst_addr = res->start + MXC_CSPITXDATA; slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; slave_config.dst_maxburst = spi_imx->wml; ret = dmaengine_slave_config(master->dma_tx, &slave_config); if (ret) { dev_err(dev, "error in TX dma configuration.\n"); goto err; } /* Prepare for RX : */ master->dma_rx = dma_request_slave_channel(dev, "rx"); if (!master->dma_rx) { dev_dbg(dev, "cannot get the DMA channel.\n"); ret = -EINVAL; goto err; } slave_config.direction = DMA_DEV_TO_MEM; slave_config.src_addr = res->start + MXC_CSPIRXDATA; slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; slave_config.src_maxburst = spi_imx->wml; ret = dmaengine_slave_config(master->dma_rx, &slave_config); if (ret) { dev_err(dev, "error in RX dma configuration.\n"); goto err; } 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; spi_imx->dma_is_inited = 1; 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_dma_transfer(struct spi_imx_data *spi_imx, struct spi_transfer *transfer) { struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; int ret; unsigned long timeout; u32 dma; int left; struct spi_master *master = spi_imx->bitbang.master; struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg; if (tx) { 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) goto no_dma; desc_tx->callback = spi_imx_dma_tx_callback; desc_tx->callback_param = (void *)spi_imx; dmaengine_submit(desc_tx); } if (rx) { 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) goto no_dma; 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); reinit_completion(&spi_imx->dma_tx_completion); /* Trigger the cspi module. */ spi_imx->dma_finished = 0; dma = readl(spi_imx->base + MX51_ECSPI_DMA); dma = dma & (~MX51_ECSPI_DMA_RXT_WML_MASK); /* Change RX_DMA_LENGTH trigger dma fetch tail data */ left = transfer->len % spi_imx->wml; if (left) writel(dma | (left << MX51_ECSPI_DMA_RXT_WML_OFFSET), spi_imx->base + MX51_ECSPI_DMA); /* * Set these order to avoid potential RX overflow. The overflow may * happen if we enable SPI HW before starting RX DMA due to rescheduling * for another task and/or interrupt. * So RX DMA enabled first to make sure data would be read out from FIFO * ASAP. TX DMA enabled next to start filling TX FIFO with new data. * And finaly SPI HW enabled to start actual data transfer. */ dma_async_issue_pending(master->dma_rx); dma_async_issue_pending(master->dma_tx); spi_imx->devtype_data->trigger(spi_imx); /* Wait SDMA to finish the data transfer.*/ timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion, IMX_DMA_TIMEOUT); if (!timeout) { pr_warn("%s %s: I/O Error in DMA TX\n", dev_driver_string(&master->dev), dev_name(&master->dev)); dmaengine_terminate_all(master->dma_tx); dmaengine_terminate_all(master->dma_rx); } else { timeout = wait_for_completion_timeout( &spi_imx->dma_rx_completion, IMX_DMA_TIMEOUT); if (!timeout) { pr_warn("%s %s: I/O Error in DMA RX\n", dev_driver_string(&master->dev), dev_name(&master->dev)); spi_imx->devtype_data->reset(spi_imx); dmaengine_terminate_all(master->dma_rx); } dma &= ~MX51_ECSPI_DMA_RXT_WML_MASK; writel(dma | spi_imx->wml << MX51_ECSPI_DMA_RXT_WML_OFFSET, spi_imx->base + MX51_ECSPI_DMA); } spi_imx->dma_finished = 1; spi_imx->devtype_data->trigger(spi_imx); if (!timeout) ret = -ETIMEDOUT; else ret = transfer->len; return ret; no_dma: pr_warn_once("%s %s: DMA not available, falling back to PIO\n", dev_driver_string(&master->dev), dev_name(&master->dev)); return -EAGAIN; } 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); 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); wait_for_completion(&spi_imx->xfer_done); return transfer->len; } static int spi_imx_transfer(struct spi_device *spi, struct spi_transfer *transfer) { int ret; struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); if (spi_imx->bitbang.master->can_dma && spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) { spi_imx->usedma = true; ret = spi_imx_dma_transfer(spi_imx, transfer); if (ret != -EAGAIN) return ret; } spi_imx->usedma = false; return spi_imx_pio_transfer(spi, transfer); } static int spi_imx_setup(struct spi_device *spi) { struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); int gpio = spi_imx->chipselect[spi->chip_select]; 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(gpio)) gpio_direction_output(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, num_cs, irq; if (!np && !mxc_platform_info) { dev_err(&pdev->dev, "can't get the platform data\n"); return -EINVAL; } ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs); if (ret < 0) { if (mxc_platform_info) num_cs = mxc_platform_info->num_chipselect; else return ret; } master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data) + sizeof(int) * num_cs); if (!master) return -ENOMEM; platform_set_drvdata(pdev, master); master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); master->bus_num = pdev->id; master->num_chipselect = num_cs; spi_imx = spi_master_get_devdata(master); spi_imx->bitbang.master = master; for (i = 0; i < master->num_chipselect; i++) { int cs_gpio = of_get_named_gpio(np, "cs-gpios", i); if (!gpio_is_valid(cs_gpio) && mxc_platform_info) cs_gpio = mxc_platform_info->chipselect[i]; spi_imx->chipselect[i] = cs_gpio; if (!gpio_is_valid(cs_gpio)) continue; ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i], DRIVER_NAME); if (ret) { dev_err(&pdev->dev, "can't get cs gpios\n"); goto out_master_put; } } 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 | SPI_LOOP; init_completion(&spi_imx->xfer_done); spi_imx->devtype_data = of_id ? of_id->data : (struct spi_imx_devtype_data *) pdev->id_entry->driver_data; 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; } 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) && spi_imx_sdma_init(&pdev->dev, spi_imx, master, res)) dev_err(&pdev->dev, "dma setup error,use pio instead\n"); 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; } 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);