/* * Copyright (C) 2009 Samsung Electronics Ltd. * Jaswinder Singh * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX_SPI_PORTS 3 #define S3C64XX_SPI_QUIRK_POLL (1 << 0) /* Registers and bit-fields */ #define S3C64XX_SPI_CH_CFG 0x00 #define S3C64XX_SPI_CLK_CFG 0x04 #define S3C64XX_SPI_MODE_CFG 0x08 #define S3C64XX_SPI_SLAVE_SEL 0x0C #define S3C64XX_SPI_INT_EN 0x10 #define S3C64XX_SPI_STATUS 0x14 #define S3C64XX_SPI_TX_DATA 0x18 #define S3C64XX_SPI_RX_DATA 0x1C #define S3C64XX_SPI_PACKET_CNT 0x20 #define S3C64XX_SPI_PENDING_CLR 0x24 #define S3C64XX_SPI_SWAP_CFG 0x28 #define S3C64XX_SPI_FB_CLK 0x2C #define S3C64XX_SPI_CH_HS_EN (1<<6) /* High Speed Enable */ #define S3C64XX_SPI_CH_SW_RST (1<<5) #define S3C64XX_SPI_CH_SLAVE (1<<4) #define S3C64XX_SPI_CPOL_L (1<<3) #define S3C64XX_SPI_CPHA_B (1<<2) #define S3C64XX_SPI_CH_RXCH_ON (1<<1) #define S3C64XX_SPI_CH_TXCH_ON (1<<0) #define S3C64XX_SPI_CLKSEL_SRCMSK (3<<9) #define S3C64XX_SPI_CLKSEL_SRCSHFT 9 #define S3C64XX_SPI_ENCLK_ENABLE (1<<8) #define S3C64XX_SPI_PSR_MASK 0xff #define S3C64XX_SPI_MODE_CH_TSZ_BYTE (0<<29) #define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD (1<<29) #define S3C64XX_SPI_MODE_CH_TSZ_WORD (2<<29) #define S3C64XX_SPI_MODE_CH_TSZ_MASK (3<<29) #define S3C64XX_SPI_MODE_BUS_TSZ_BYTE (0<<17) #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17) #define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17) #define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17) #define S3C64XX_SPI_MODE_RXDMA_ON (1<<2) #define S3C64XX_SPI_MODE_TXDMA_ON (1<<1) #define S3C64XX_SPI_MODE_4BURST (1<<0) #define S3C64XX_SPI_SLAVE_AUTO (1<<1) #define S3C64XX_SPI_SLAVE_SIG_INACT (1<<0) #define S3C64XX_SPI_INT_TRAILING_EN (1<<6) #define S3C64XX_SPI_INT_RX_OVERRUN_EN (1<<5) #define S3C64XX_SPI_INT_RX_UNDERRUN_EN (1<<4) #define S3C64XX_SPI_INT_TX_OVERRUN_EN (1<<3) #define S3C64XX_SPI_INT_TX_UNDERRUN_EN (1<<2) #define S3C64XX_SPI_INT_RX_FIFORDY_EN (1<<1) #define S3C64XX_SPI_INT_TX_FIFORDY_EN (1<<0) #define S3C64XX_SPI_ST_RX_OVERRUN_ERR (1<<5) #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR (1<<4) #define S3C64XX_SPI_ST_TX_OVERRUN_ERR (1<<3) #define S3C64XX_SPI_ST_TX_UNDERRUN_ERR (1<<2) #define S3C64XX_SPI_ST_RX_FIFORDY (1<<1) #define S3C64XX_SPI_ST_TX_FIFORDY (1<<0) #define S3C64XX_SPI_PACKET_CNT_EN (1<<16) #define S3C64XX_SPI_PND_TX_UNDERRUN_CLR (1<<4) #define S3C64XX_SPI_PND_TX_OVERRUN_CLR (1<<3) #define S3C64XX_SPI_PND_RX_UNDERRUN_CLR (1<<2) #define S3C64XX_SPI_PND_RX_OVERRUN_CLR (1<<1) #define S3C64XX_SPI_PND_TRAILING_CLR (1<<0) #define S3C64XX_SPI_SWAP_RX_HALF_WORD (1<<7) #define S3C64XX_SPI_SWAP_RX_BYTE (1<<6) #define S3C64XX_SPI_SWAP_RX_BIT (1<<5) #define S3C64XX_SPI_SWAP_RX_EN (1<<4) #define S3C64XX_SPI_SWAP_TX_HALF_WORD (1<<3) #define S3C64XX_SPI_SWAP_TX_BYTE (1<<2) #define S3C64XX_SPI_SWAP_TX_BIT (1<<1) #define S3C64XX_SPI_SWAP_TX_EN (1<<0) #define S3C64XX_SPI_FBCLK_MSK (3<<0) #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id]) #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \ (1 << (i)->port_conf->tx_st_done)) ? 1 : 0) #define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i)) #define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \ FIFO_LVL_MASK(i)) #define S3C64XX_SPI_MAX_TRAILCNT 0x3ff #define S3C64XX_SPI_TRAILCNT_OFF 19 #define S3C64XX_SPI_TRAILCNT S3C64XX_SPI_MAX_TRAILCNT #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t) #define is_polling(x) (x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL) #define RXBUSY (1<<2) #define TXBUSY (1<<3) struct s3c64xx_spi_dma_data { struct dma_chan *ch; enum dma_transfer_direction direction; unsigned int dmach; }; /** * struct s3c64xx_spi_info - SPI Controller hardware info * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register. * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter. * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter. * @high_speed: True, if the controller supports HIGH_SPEED_EN bit. * @clk_from_cmu: True, if the controller does not include a clock mux and * prescaler unit. * * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but * differ in some aspects such as the size of the fifo and spi bus clock * setup. Such differences are specified to the driver using this structure * which is provided as driver data to the driver. */ struct s3c64xx_spi_port_config { int fifo_lvl_mask[MAX_SPI_PORTS]; int rx_lvl_offset; int tx_st_done; int quirks; bool high_speed; bool clk_from_cmu; }; /** * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver. * @clk: Pointer to the spi clock. * @src_clk: Pointer to the clock used to generate SPI signals. * @master: Pointer to the SPI Protocol master. * @cntrlr_info: Platform specific data for the controller this driver manages. * @tgl_spi: Pointer to the last CS left untoggled by the cs_change hint. * @lock: Controller specific lock. * @state: Set of FLAGS to indicate status. * @rx_dmach: Controller's DMA channel for Rx. * @tx_dmach: Controller's DMA channel for Tx. * @sfr_start: BUS address of SPI controller regs. * @regs: Pointer to ioremap'ed controller registers. * @irq: interrupt * @xfer_completion: To indicate completion of xfer task. * @cur_mode: Stores the active configuration of the controller. * @cur_bpw: Stores the active bits per word settings. * @cur_speed: Stores the active xfer clock speed. */ struct s3c64xx_spi_driver_data { void __iomem *regs; struct clk *clk; struct clk *src_clk; struct platform_device *pdev; struct spi_master *master; struct s3c64xx_spi_info *cntrlr_info; struct spi_device *tgl_spi; spinlock_t lock; unsigned long sfr_start; struct completion xfer_completion; unsigned state; unsigned cur_mode, cur_bpw; unsigned cur_speed; struct s3c64xx_spi_dma_data rx_dma; struct s3c64xx_spi_dma_data tx_dma; struct s3c64xx_spi_port_config *port_conf; unsigned int port_id; bool cs_gpio; }; static void flush_fifo(struct s3c64xx_spi_driver_data *sdd) { void __iomem *regs = sdd->regs; unsigned long loops; u32 val; writel(0, regs + S3C64XX_SPI_PACKET_CNT); val = readl(regs + S3C64XX_SPI_CH_CFG); val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON); writel(val, regs + S3C64XX_SPI_CH_CFG); val = readl(regs + S3C64XX_SPI_CH_CFG); val |= S3C64XX_SPI_CH_SW_RST; val &= ~S3C64XX_SPI_CH_HS_EN; writel(val, regs + S3C64XX_SPI_CH_CFG); /* Flush TxFIFO*/ loops = msecs_to_loops(1); do { val = readl(regs + S3C64XX_SPI_STATUS); } while (TX_FIFO_LVL(val, sdd) && loops--); if (loops == 0) dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n"); /* Flush RxFIFO*/ loops = msecs_to_loops(1); do { val = readl(regs + S3C64XX_SPI_STATUS); if (RX_FIFO_LVL(val, sdd)) readl(regs + S3C64XX_SPI_RX_DATA); else break; } while (loops--); if (loops == 0) dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n"); val = readl(regs + S3C64XX_SPI_CH_CFG); val &= ~S3C64XX_SPI_CH_SW_RST; writel(val, regs + S3C64XX_SPI_CH_CFG); val = readl(regs + S3C64XX_SPI_MODE_CFG); val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON); writel(val, regs + S3C64XX_SPI_MODE_CFG); } static void s3c64xx_spi_dmacb(void *data) { struct s3c64xx_spi_driver_data *sdd; struct s3c64xx_spi_dma_data *dma = data; unsigned long flags; if (dma->direction == DMA_DEV_TO_MEM) sdd = container_of(data, struct s3c64xx_spi_driver_data, rx_dma); else sdd = container_of(data, struct s3c64xx_spi_driver_data, tx_dma); spin_lock_irqsave(&sdd->lock, flags); if (dma->direction == DMA_DEV_TO_MEM) { sdd->state &= ~RXBUSY; if (!(sdd->state & TXBUSY)) complete(&sdd->xfer_completion); } else { sdd->state &= ~TXBUSY; if (!(sdd->state & RXBUSY)) complete(&sdd->xfer_completion); } spin_unlock_irqrestore(&sdd->lock, flags); } static void prepare_dma(struct s3c64xx_spi_dma_data *dma, struct sg_table *sgt) { struct s3c64xx_spi_driver_data *sdd; struct dma_slave_config config; struct dma_async_tx_descriptor *desc; memset(&config, 0, sizeof(config)); if (dma->direction == DMA_DEV_TO_MEM) { sdd = container_of((void *)dma, struct s3c64xx_spi_driver_data, rx_dma); config.direction = dma->direction; config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA; config.src_addr_width = sdd->cur_bpw / 8; config.src_maxburst = 1; dmaengine_slave_config(dma->ch, &config); } else { sdd = container_of((void *)dma, struct s3c64xx_spi_driver_data, tx_dma); config.direction = dma->direction; config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA; config.dst_addr_width = sdd->cur_bpw / 8; config.dst_maxburst = 1; dmaengine_slave_config(dma->ch, &config); } desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents, dma->direction, DMA_PREP_INTERRUPT); desc->callback = s3c64xx_spi_dmacb; desc->callback_param = dma; dmaengine_submit(desc); dma_async_issue_pending(dma->ch); } static int s3c64xx_spi_prepare_transfer(struct spi_master *spi) { struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi); dma_filter_fn filter = sdd->cntrlr_info->filter; struct device *dev = &sdd->pdev->dev; dma_cap_mask_t mask; int ret; if (!is_polling(sdd)) { dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); /* Acquire DMA channels */ sdd->rx_dma.ch = dma_request_slave_channel_compat(mask, filter, (void *)sdd->rx_dma.dmach, dev, "rx"); if (!sdd->rx_dma.ch) { dev_err(dev, "Failed to get RX DMA channel\n"); ret = -EBUSY; goto out; } spi->dma_rx = sdd->rx_dma.ch; sdd->tx_dma.ch = dma_request_slave_channel_compat(mask, filter, (void *)sdd->tx_dma.dmach, dev, "tx"); if (!sdd->tx_dma.ch) { dev_err(dev, "Failed to get TX DMA channel\n"); ret = -EBUSY; goto out_rx; } spi->dma_tx = sdd->tx_dma.ch; } ret = pm_runtime_get_sync(&sdd->pdev->dev); if (ret < 0) { dev_err(dev, "Failed to enable device: %d\n", ret); goto out_tx; } return 0; out_tx: dma_release_channel(sdd->tx_dma.ch); out_rx: dma_release_channel(sdd->rx_dma.ch); out: return ret; } static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi) { struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi); /* Free DMA channels */ if (!is_polling(sdd)) { dma_release_channel(sdd->rx_dma.ch); dma_release_channel(sdd->tx_dma.ch); } pm_runtime_put(&sdd->pdev->dev); return 0; } static bool s3c64xx_spi_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1; } static void enable_datapath(struct s3c64xx_spi_driver_data *sdd, struct spi_device *spi, struct spi_transfer *xfer, int dma_mode) { void __iomem *regs = sdd->regs; u32 modecfg, chcfg; modecfg = readl(regs + S3C64XX_SPI_MODE_CFG); modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON); chcfg = readl(regs + S3C64XX_SPI_CH_CFG); chcfg &= ~S3C64XX_SPI_CH_TXCH_ON; if (dma_mode) { chcfg &= ~S3C64XX_SPI_CH_RXCH_ON; } else { /* Always shift in data in FIFO, even if xfer is Tx only, * this helps setting PCKT_CNT value for generating clocks * as exactly needed. */ chcfg |= S3C64XX_SPI_CH_RXCH_ON; writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff) | S3C64XX_SPI_PACKET_CNT_EN, regs + S3C64XX_SPI_PACKET_CNT); } if (xfer->tx_buf != NULL) { sdd->state |= TXBUSY; chcfg |= S3C64XX_SPI_CH_TXCH_ON; if (dma_mode) { modecfg |= S3C64XX_SPI_MODE_TXDMA_ON; prepare_dma(&sdd->tx_dma, &xfer->tx_sg); } else { switch (sdd->cur_bpw) { case 32: iowrite32_rep(regs + S3C64XX_SPI_TX_DATA, xfer->tx_buf, xfer->len / 4); break; case 16: iowrite16_rep(regs + S3C64XX_SPI_TX_DATA, xfer->tx_buf, xfer->len / 2); break; default: iowrite8_rep(regs + S3C64XX_SPI_TX_DATA, xfer->tx_buf, xfer->len); break; } } } if (xfer->rx_buf != NULL) { sdd->state |= RXBUSY; if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL && !(sdd->cur_mode & SPI_CPHA)) chcfg |= S3C64XX_SPI_CH_HS_EN; if (dma_mode) { modecfg |= S3C64XX_SPI_MODE_RXDMA_ON; chcfg |= S3C64XX_SPI_CH_RXCH_ON; writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff) | S3C64XX_SPI_PACKET_CNT_EN, regs + S3C64XX_SPI_PACKET_CNT); prepare_dma(&sdd->rx_dma, &xfer->rx_sg); } } writel(modecfg, regs + S3C64XX_SPI_MODE_CFG); writel(chcfg, regs + S3C64XX_SPI_CH_CFG); } static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, int timeout_ms) { void __iomem *regs = sdd->regs; unsigned long val = 1; u32 status; /* max fifo depth available */ u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1; if (timeout_ms) val = msecs_to_loops(timeout_ms); do { status = readl(regs + S3C64XX_SPI_STATUS); } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val); /* return the actual received data length */ return RX_FIFO_LVL(status, sdd); } static int wait_for_dma(struct s3c64xx_spi_driver_data *sdd, struct spi_transfer *xfer) { void __iomem *regs = sdd->regs; unsigned long val; u32 status; int ms; /* millisecs to xfer 'len' bytes @ 'cur_speed' */ ms = xfer->len * 8 * 1000 / sdd->cur_speed; ms += 10; /* some tolerance */ val = msecs_to_jiffies(ms) + 10; val = wait_for_completion_timeout(&sdd->xfer_completion, val); /* * If the previous xfer was completed within timeout, then * proceed further else return -EIO. * DmaTx returns after simply writing data in the FIFO, * w/o waiting for real transmission on the bus to finish. * DmaRx returns only after Dma read data from FIFO which * needs bus transmission to finish, so we don't worry if * Xfer involved Rx(with or without Tx). */ if (val && !xfer->rx_buf) { val = msecs_to_loops(10); status = readl(regs + S3C64XX_SPI_STATUS); while ((TX_FIFO_LVL(status, sdd) || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) && --val) { cpu_relax(); status = readl(regs + S3C64XX_SPI_STATUS); } } /* If timed out while checking rx/tx status return error */ if (!val) return -EIO; return 0; } static int wait_for_pio(struct s3c64xx_spi_driver_data *sdd, struct spi_transfer *xfer) { void __iomem *regs = sdd->regs; unsigned long val; u32 status; int loops; u32 cpy_len; u8 *buf; int ms; /* millisecs to xfer 'len' bytes @ 'cur_speed' */ ms = xfer->len * 8 * 1000 / sdd->cur_speed; ms += 10; /* some tolerance */ val = msecs_to_loops(ms); do { status = readl(regs + S3C64XX_SPI_STATUS); } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); /* If it was only Tx */ if (!xfer->rx_buf) { sdd->state &= ~TXBUSY; return 0; } /* * If the receive length is bigger than the controller fifo * size, calculate the loops and read the fifo as many times. * loops = length / max fifo size (calculated by using the * fifo mask). * For any size less than the fifo size the below code is * executed atleast once. */ loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1); buf = xfer->rx_buf; do { /* wait for data to be received in the fifo */ cpy_len = s3c64xx_spi_wait_for_timeout(sdd, (loops ? ms : 0)); switch (sdd->cur_bpw) { case 32: ioread32_rep(regs + S3C64XX_SPI_RX_DATA, buf, cpy_len / 4); break; case 16: ioread16_rep(regs + S3C64XX_SPI_RX_DATA, buf, cpy_len / 2); break; default: ioread8_rep(regs + S3C64XX_SPI_RX_DATA, buf, cpy_len); break; } buf = buf + cpy_len; } while (loops--); sdd->state &= ~RXBUSY; return 0; } static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd) { void __iomem *regs = sdd->regs; u32 val; /* Disable Clock */ if (sdd->port_conf->clk_from_cmu) { clk_disable_unprepare(sdd->src_clk); } else { val = readl(regs + S3C64XX_SPI_CLK_CFG); val &= ~S3C64XX_SPI_ENCLK_ENABLE; writel(val, regs + S3C64XX_SPI_CLK_CFG); } /* Set Polarity and Phase */ val = readl(regs + S3C64XX_SPI_CH_CFG); val &= ~(S3C64XX_SPI_CH_SLAVE | S3C64XX_SPI_CPOL_L | S3C64XX_SPI_CPHA_B); if (sdd->cur_mode & SPI_CPOL) val |= S3C64XX_SPI_CPOL_L; if (sdd->cur_mode & SPI_CPHA) val |= S3C64XX_SPI_CPHA_B; writel(val, regs + S3C64XX_SPI_CH_CFG); /* Set Channel & DMA Mode */ val = readl(regs + S3C64XX_SPI_MODE_CFG); val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK | S3C64XX_SPI_MODE_CH_TSZ_MASK); switch (sdd->cur_bpw) { case 32: val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD; val |= S3C64XX_SPI_MODE_CH_TSZ_WORD; break; case 16: val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD; val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD; break; default: val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE; val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE; break; } writel(val, regs + S3C64XX_SPI_MODE_CFG); if (sdd->port_conf->clk_from_cmu) { /* Configure Clock */ /* There is half-multiplier before the SPI */ clk_set_rate(sdd->src_clk, sdd->cur_speed * 2); /* Enable Clock */ clk_prepare_enable(sdd->src_clk); } else { /* Configure Clock */ val = readl(regs + S3C64XX_SPI_CLK_CFG); val &= ~S3C64XX_SPI_PSR_MASK; val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1) & S3C64XX_SPI_PSR_MASK); writel(val, regs + S3C64XX_SPI_CLK_CFG); /* Enable Clock */ val = readl(regs + S3C64XX_SPI_CLK_CFG); val |= S3C64XX_SPI_ENCLK_ENABLE; writel(val, regs + S3C64XX_SPI_CLK_CFG); } } #define XFER_DMAADDR_INVALID DMA_BIT_MASK(32) static int s3c64xx_spi_prepare_message(struct spi_master *master, struct spi_message *msg) { struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); struct spi_device *spi = msg->spi; struct s3c64xx_spi_csinfo *cs = spi->controller_data; /* If Master's(controller) state differs from that needed by Slave */ if (sdd->cur_speed != spi->max_speed_hz || sdd->cur_mode != spi->mode || sdd->cur_bpw != spi->bits_per_word) { sdd->cur_bpw = spi->bits_per_word; sdd->cur_speed = spi->max_speed_hz; sdd->cur_mode = spi->mode; s3c64xx_spi_config(sdd); } /* Configure feedback delay */ writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK); return 0; } static int s3c64xx_spi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); int status; u32 speed; u8 bpw; unsigned long flags; int use_dma; reinit_completion(&sdd->xfer_completion); /* Only BPW and Speed may change across transfers */ bpw = xfer->bits_per_word; speed = xfer->speed_hz ? : spi->max_speed_hz; if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) { sdd->cur_bpw = bpw; sdd->cur_speed = speed; s3c64xx_spi_config(sdd); } /* Polling method for xfers not bigger than FIFO capacity */ use_dma = 0; if (!is_polling(sdd) && (sdd->rx_dma.ch && sdd->tx_dma.ch && (xfer->len > ((FIFO_LVL_MASK(sdd) >> 1) + 1)))) use_dma = 1; spin_lock_irqsave(&sdd->lock, flags); /* Pending only which is to be done */ sdd->state &= ~RXBUSY; sdd->state &= ~TXBUSY; enable_datapath(sdd, spi, xfer, use_dma); /* Start the signals */ writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL); spin_unlock_irqrestore(&sdd->lock, flags); if (use_dma) status = wait_for_dma(sdd, xfer); else status = wait_for_pio(sdd, xfer); if (status) { dev_err(&spi->dev, "I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n", xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0, (sdd->state & RXBUSY) ? 'f' : 'p', (sdd->state & TXBUSY) ? 'f' : 'p', xfer->len); if (use_dma) { if (xfer->tx_buf != NULL && (sdd->state & TXBUSY)) dmaengine_terminate_all(sdd->tx_dma.ch); if (xfer->rx_buf != NULL && (sdd->state & RXBUSY)) dmaengine_terminate_all(sdd->rx_dma.ch); } } else { flush_fifo(sdd); } return status; } static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata( struct spi_device *spi) { struct s3c64xx_spi_csinfo *cs; struct device_node *slave_np, *data_np = NULL; struct s3c64xx_spi_driver_data *sdd; u32 fb_delay = 0; sdd = spi_master_get_devdata(spi->master); slave_np = spi->dev.of_node; if (!slave_np) { dev_err(&spi->dev, "device node not found\n"); return ERR_PTR(-EINVAL); } data_np = of_get_child_by_name(slave_np, "controller-data"); if (!data_np) { dev_err(&spi->dev, "child node 'controller-data' not found\n"); return ERR_PTR(-EINVAL); } cs = kzalloc(sizeof(*cs), GFP_KERNEL); if (!cs) { of_node_put(data_np); return ERR_PTR(-ENOMEM); } /* The CS line is asserted/deasserted by the gpio pin */ if (sdd->cs_gpio) cs->line = of_get_named_gpio(data_np, "cs-gpio", 0); if (!gpio_is_valid(cs->line)) { dev_err(&spi->dev, "chip select gpio is not specified or invalid\n"); kfree(cs); of_node_put(data_np); return ERR_PTR(-EINVAL); } of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay); cs->fb_delay = fb_delay; of_node_put(data_np); return cs; } /* * Here we only check the validity of requested configuration * and save the configuration in a local data-structure. * The controller is actually configured only just before we * get a message to transfer. */ static int s3c64xx_spi_setup(struct spi_device *spi) { struct s3c64xx_spi_csinfo *cs = spi->controller_data; struct s3c64xx_spi_driver_data *sdd; struct s3c64xx_spi_info *sci; int err; sdd = spi_master_get_devdata(spi->master); if (!cs && spi->dev.of_node) { cs = s3c64xx_get_slave_ctrldata(spi); spi->controller_data = cs; } if (IS_ERR_OR_NULL(cs)) { dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select); return -ENODEV; } if (!spi_get_ctldata(spi)) { /* Request gpio only if cs line is asserted by gpio pins */ if (sdd->cs_gpio) { err = gpio_request_one(cs->line, GPIOF_OUT_INIT_HIGH, dev_name(&spi->dev)); if (err) { dev_err(&spi->dev, "Failed to get /CS gpio [%d]: %d\n", cs->line, err); goto err_gpio_req; } spi->cs_gpio = cs->line; } spi_set_ctldata(spi, cs); } sci = sdd->cntrlr_info; pm_runtime_get_sync(&sdd->pdev->dev); /* Check if we can provide the requested rate */ if (!sdd->port_conf->clk_from_cmu) { u32 psr, speed; /* Max possible */ speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1); if (spi->max_speed_hz > speed) spi->max_speed_hz = speed; psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1; psr &= S3C64XX_SPI_PSR_MASK; if (psr == S3C64XX_SPI_PSR_MASK) psr--; speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1); if (spi->max_speed_hz < speed) { if (psr+1 < S3C64XX_SPI_PSR_MASK) { psr++; } else { err = -EINVAL; goto setup_exit; } } speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1); if (spi->max_speed_hz >= speed) { spi->max_speed_hz = speed; } else { dev_err(&spi->dev, "Can't set %dHz transfer speed\n", spi->max_speed_hz); err = -EINVAL; goto setup_exit; } } pm_runtime_put(&sdd->pdev->dev); writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); return 0; setup_exit: pm_runtime_put(&sdd->pdev->dev); /* setup() returns with device de-selected */ writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); gpio_free(cs->line); spi_set_ctldata(spi, NULL); err_gpio_req: if (spi->dev.of_node) kfree(cs); return err; } static void s3c64xx_spi_cleanup(struct spi_device *spi) { struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi); struct s3c64xx_spi_driver_data *sdd; sdd = spi_master_get_devdata(spi->master); if (spi->cs_gpio) { gpio_free(spi->cs_gpio); if (spi->dev.of_node) kfree(cs); } spi_set_ctldata(spi, NULL); } static irqreturn_t s3c64xx_spi_irq(int irq, void *data) { struct s3c64xx_spi_driver_data *sdd = data; struct spi_master *spi = sdd->master; unsigned int val, clr = 0; val = readl(sdd->regs + S3C64XX_SPI_STATUS); if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) { clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR; dev_err(&spi->dev, "RX overrun\n"); } if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) { clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR; dev_err(&spi->dev, "RX underrun\n"); } if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) { clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR; dev_err(&spi->dev, "TX overrun\n"); } if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) { clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR; dev_err(&spi->dev, "TX underrun\n"); } /* Clear the pending irq by setting and then clearing it */ writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR); writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR); return IRQ_HANDLED; } static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel) { struct s3c64xx_spi_info *sci = sdd->cntrlr_info; void __iomem *regs = sdd->regs; unsigned int val; sdd->cur_speed = 0; writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL); /* Disable Interrupts - we use Polling if not DMA mode */ writel(0, regs + S3C64XX_SPI_INT_EN); if (!sdd->port_conf->clk_from_cmu) writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT, regs + S3C64XX_SPI_CLK_CFG); writel(0, regs + S3C64XX_SPI_MODE_CFG); writel(0, regs + S3C64XX_SPI_PACKET_CNT); /* Clear any irq pending bits, should set and clear the bits */ val = S3C64XX_SPI_PND_RX_OVERRUN_CLR | S3C64XX_SPI_PND_RX_UNDERRUN_CLR | S3C64XX_SPI_PND_TX_OVERRUN_CLR | S3C64XX_SPI_PND_TX_UNDERRUN_CLR; writel(val, regs + S3C64XX_SPI_PENDING_CLR); writel(0, regs + S3C64XX_SPI_PENDING_CLR); writel(0, regs + S3C64XX_SPI_SWAP_CFG); val = readl(regs + S3C64XX_SPI_MODE_CFG); val &= ~S3C64XX_SPI_MODE_4BURST; val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF); val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF); writel(val, regs + S3C64XX_SPI_MODE_CFG); flush_fifo(sdd); } #ifdef CONFIG_OF static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev) { struct s3c64xx_spi_info *sci; u32 temp; sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL); if (!sci) return ERR_PTR(-ENOMEM); if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) { dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n"); sci->src_clk_nr = 0; } else { sci->src_clk_nr = temp; } if (of_property_read_u32(dev->of_node, "num-cs", &temp)) { dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n"); sci->num_cs = 1; } else { sci->num_cs = temp; } return sci; } #else static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev) { return dev_get_platdata(dev); } #endif static const struct of_device_id s3c64xx_spi_dt_match[]; static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config( struct platform_device *pdev) { #ifdef CONFIG_OF if (pdev->dev.of_node) { const struct of_device_id *match; match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node); return (struct s3c64xx_spi_port_config *)match->data; } #endif return (struct s3c64xx_spi_port_config *) platform_get_device_id(pdev)->driver_data; } static int s3c64xx_spi_probe(struct platform_device *pdev) { struct resource *mem_res; struct resource *res; struct s3c64xx_spi_driver_data *sdd; struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev); struct spi_master *master; int ret, irq; char clk_name[16]; if (!sci && pdev->dev.of_node) { sci = s3c64xx_spi_parse_dt(&pdev->dev); if (IS_ERR(sci)) return PTR_ERR(sci); } if (!sci) { dev_err(&pdev->dev, "platform_data missing!\n"); return -ENODEV; } mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (mem_res == NULL) { dev_err(&pdev->dev, "Unable to get SPI MEM resource\n"); return -ENXIO; } irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq); return irq; } master = spi_alloc_master(&pdev->dev, sizeof(struct s3c64xx_spi_driver_data)); if (master == NULL) { dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); return -ENOMEM; } platform_set_drvdata(pdev, master); sdd = spi_master_get_devdata(master); sdd->port_conf = s3c64xx_spi_get_port_config(pdev); sdd->master = master; sdd->cntrlr_info = sci; sdd->pdev = pdev; sdd->sfr_start = mem_res->start; sdd->cs_gpio = true; if (pdev->dev.of_node) { if (!of_find_property(pdev->dev.of_node, "cs-gpio", NULL)) sdd->cs_gpio = false; ret = of_alias_get_id(pdev->dev.of_node, "spi"); if (ret < 0) { dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret); goto err0; } sdd->port_id = ret; } else { sdd->port_id = pdev->id; } sdd->cur_bpw = 8; if (!sdd->pdev->dev.of_node) { res = platform_get_resource(pdev, IORESOURCE_DMA, 0); if (!res) { dev_warn(&pdev->dev, "Unable to get SPI tx dma resource. Switching to poll mode\n"); sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL; } else sdd->tx_dma.dmach = res->start; res = platform_get_resource(pdev, IORESOURCE_DMA, 1); if (!res) { dev_warn(&pdev->dev, "Unable to get SPI rx dma resource. Switching to poll mode\n"); sdd->port_conf->quirks = S3C64XX_SPI_QUIRK_POLL; } else sdd->rx_dma.dmach = res->start; } sdd->tx_dma.direction = DMA_MEM_TO_DEV; sdd->rx_dma.direction = DMA_DEV_TO_MEM; master->dev.of_node = pdev->dev.of_node; master->bus_num = sdd->port_id; master->setup = s3c64xx_spi_setup; master->cleanup = s3c64xx_spi_cleanup; master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer; master->prepare_message = s3c64xx_spi_prepare_message; master->transfer_one = s3c64xx_spi_transfer_one; master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer; master->num_chipselect = sci->num_cs; master->dma_alignment = 8; master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | SPI_BPW_MASK(8); /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; master->auto_runtime_pm = true; if (!is_polling(sdd)) master->can_dma = s3c64xx_spi_can_dma; sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res); if (IS_ERR(sdd->regs)) { ret = PTR_ERR(sdd->regs); goto err0; } if (sci->cfg_gpio && sci->cfg_gpio()) { dev_err(&pdev->dev, "Unable to config gpio\n"); ret = -EBUSY; goto err0; } /* Setup clocks */ sdd->clk = devm_clk_get(&pdev->dev, "spi"); if (IS_ERR(sdd->clk)) { dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n"); ret = PTR_ERR(sdd->clk); goto err0; } if (clk_prepare_enable(sdd->clk)) { dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n"); ret = -EBUSY; goto err0; } sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr); sdd->src_clk = devm_clk_get(&pdev->dev, clk_name); if (IS_ERR(sdd->src_clk)) { dev_err(&pdev->dev, "Unable to acquire clock '%s'\n", clk_name); ret = PTR_ERR(sdd->src_clk); goto err2; } if (clk_prepare_enable(sdd->src_clk)) { dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name); ret = -EBUSY; goto err2; } /* Setup Deufult Mode */ s3c64xx_spi_hwinit(sdd, sdd->port_id); spin_lock_init(&sdd->lock); init_completion(&sdd->xfer_completion); ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0, "spi-s3c64xx", sdd); if (ret != 0) { dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n", irq, ret); goto err3; } writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN | S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN, sdd->regs + S3C64XX_SPI_INT_EN); pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); ret = devm_spi_register_master(&pdev->dev, master); if (ret != 0) { dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret); goto err3; } dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n", sdd->port_id, master->num_chipselect); dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tDMA=[Rx-%d, Tx-%d]\n", mem_res, sdd->rx_dma.dmach, sdd->tx_dma.dmach); return 0; err3: clk_disable_unprepare(sdd->src_clk); err2: clk_disable_unprepare(sdd->clk); err0: spi_master_put(master); return ret; } static int s3c64xx_spi_remove(struct platform_device *pdev) { struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); pm_runtime_disable(&pdev->dev); writel(0, sdd->regs + S3C64XX_SPI_INT_EN); clk_disable_unprepare(sdd->src_clk); clk_disable_unprepare(sdd->clk); return 0; } #ifdef CONFIG_PM_SLEEP static int s3c64xx_spi_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); int ret = spi_master_suspend(master); if (ret) return ret; if (!pm_runtime_suspended(dev)) { clk_disable_unprepare(sdd->clk); clk_disable_unprepare(sdd->src_clk); } sdd->cur_speed = 0; /* Output Clock is stopped */ return 0; } static int s3c64xx_spi_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); struct s3c64xx_spi_info *sci = sdd->cntrlr_info; if (sci->cfg_gpio) sci->cfg_gpio(); if (!pm_runtime_suspended(dev)) { clk_prepare_enable(sdd->src_clk); clk_prepare_enable(sdd->clk); } s3c64xx_spi_hwinit(sdd, sdd->port_id); return spi_master_resume(master); } #endif /* CONFIG_PM_SLEEP */ #ifdef CONFIG_PM_RUNTIME static int s3c64xx_spi_runtime_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); clk_disable_unprepare(sdd->clk); clk_disable_unprepare(sdd->src_clk); return 0; } static int s3c64xx_spi_runtime_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master); int ret; ret = clk_prepare_enable(sdd->src_clk); if (ret != 0) return ret; ret = clk_prepare_enable(sdd->clk); if (ret != 0) { clk_disable_unprepare(sdd->src_clk); return ret; } return 0; } #endif /* CONFIG_PM_RUNTIME */ static const struct dev_pm_ops s3c64xx_spi_pm = { SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume) SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend, s3c64xx_spi_runtime_resume, NULL) }; static struct s3c64xx_spi_port_config s3c2443_spi_port_config = { .fifo_lvl_mask = { 0x7f }, .rx_lvl_offset = 13, .tx_st_done = 21, .high_speed = true, }; static struct s3c64xx_spi_port_config s3c6410_spi_port_config = { .fifo_lvl_mask = { 0x7f, 0x7F }, .rx_lvl_offset = 13, .tx_st_done = 21, }; static struct s3c64xx_spi_port_config s5pv210_spi_port_config = { .fifo_lvl_mask = { 0x1ff, 0x7F }, .rx_lvl_offset = 15, .tx_st_done = 25, .high_speed = true, }; static struct s3c64xx_spi_port_config exynos4_spi_port_config = { .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F }, .rx_lvl_offset = 15, .tx_st_done = 25, .high_speed = true, .clk_from_cmu = true, }; static struct s3c64xx_spi_port_config exynos5440_spi_port_config = { .fifo_lvl_mask = { 0x1ff }, .rx_lvl_offset = 15, .tx_st_done = 25, .high_speed = true, .clk_from_cmu = true, .quirks = S3C64XX_SPI_QUIRK_POLL, }; static struct platform_device_id s3c64xx_spi_driver_ids[] = { { .name = "s3c2443-spi", .driver_data = (kernel_ulong_t)&s3c2443_spi_port_config, }, { .name = "s3c6410-spi", .driver_data = (kernel_ulong_t)&s3c6410_spi_port_config, }, { .name = "s5pv210-spi", .driver_data = (kernel_ulong_t)&s5pv210_spi_port_config, }, { .name = "exynos4210-spi", .driver_data = (kernel_ulong_t)&exynos4_spi_port_config, }, { }, }; static const struct of_device_id s3c64xx_spi_dt_match[] = { { .compatible = "samsung,s3c2443-spi", .data = (void *)&s3c2443_spi_port_config, }, { .compatible = "samsung,s3c6410-spi", .data = (void *)&s3c6410_spi_port_config, }, { .compatible = "samsung,s5pv210-spi", .data = (void *)&s5pv210_spi_port_config, }, { .compatible = "samsung,exynos4210-spi", .data = (void *)&exynos4_spi_port_config, }, { .compatible = "samsung,exynos5440-spi", .data = (void *)&exynos5440_spi_port_config, }, { }, }; MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match); static struct platform_driver s3c64xx_spi_driver = { .driver = { .name = "s3c64xx-spi", .owner = THIS_MODULE, .pm = &s3c64xx_spi_pm, .of_match_table = of_match_ptr(s3c64xx_spi_dt_match), }, .probe = s3c64xx_spi_probe, .remove = s3c64xx_spi_remove, .id_table = s3c64xx_spi_driver_ids, }; MODULE_ALIAS("platform:s3c64xx-spi"); module_platform_driver(s3c64xx_spi_driver); MODULE_AUTHOR("Jaswinder Singh "); MODULE_DESCRIPTION("S3C64XX SPI Controller Driver"); MODULE_LICENSE("GPL");