--- /dev/null
+/* linux/drivers/spi/spi_s3c64xx.c
+ *
+ * Copyright (C) 2009 Samsung Electronics Ltd.
+ * Jaswinder Singh <jassi.brar@samsung.com>
+ *
+ * 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 <linux/init.h>
+#include <linux/module.h>
+#include <linux/workqueue.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#include <mach/dma.h>
+#include <plat/spi.h>
+
+/* 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_ACT(c) writel(0, (c)->regs + S3C64XX_SPI_SLAVE_SEL)
+
+#define S3C64XX_SPI_DEACT(c) writel(S3C64XX_SPI_SLAVE_SIG_INACT, \
+ (c)->regs + S3C64XX_SPI_SLAVE_SEL)
+
+#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 S3C64XX_SPI_ST_TRLCNTZ(v, i) ((((v) >> (i)->rx_lvl_offset) & \
+ (((i)->fifo_lvl_mask + 1))) \
+ ? 1 : 0)
+
+#define S3C64XX_SPI_ST_TX_DONE(v, i) ((((v) >> (i)->rx_lvl_offset) & \
+ (((i)->fifo_lvl_mask + 1) << 1)) \
+ ? 1 : 0)
+#define TX_FIFO_LVL(v, i) (((v) >> 6) & (i)->fifo_lvl_mask)
+#define RX_FIFO_LVL(v, i) (((v) >> (i)->rx_lvl_offset) & (i)->fifo_lvl_mask)
+
+#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 SUSPND (1<<0)
+#define SPIBUSY (1<<1)
+#define RXBUSY (1<<2)
+#define TXBUSY (1<<3)
+
+/**
+ * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
+ * @clk: Pointer to the spi clock.
+ * @master: Pointer to the SPI Protocol master.
+ * @workqueue: Work queue for the SPI xfer requests.
+ * @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.
+ * @work: Work
+ * @queue: To log SPI xfer requests.
+ * @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.
+ * @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 platform_device *pdev;
+ struct spi_master *master;
+ struct workqueue_struct *workqueue;
+ struct s3c64xx_spi_cntrlr_info *cntrlr_info;
+ struct spi_device *tgl_spi;
+ struct work_struct work;
+ struct list_head queue;
+ spinlock_t lock;
+ enum dma_ch rx_dmach;
+ enum dma_ch tx_dmach;
+ unsigned long sfr_start;
+ struct completion xfer_completion;
+ unsigned state;
+ unsigned cur_mode, cur_bpw;
+ unsigned cur_speed;
+};
+
+static struct s3c2410_dma_client s3c64xx_spi_dma_client = {
+ .name = "samsung-spi-dma",
+};
+
+static void flush_fifo(struct s3c64xx_spi_driver_data *sdd)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ 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_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, sci) && loops--);
+
+ /* Flush RxFIFO*/
+ loops = msecs_to_loops(1);
+ do {
+ val = readl(regs + S3C64XX_SPI_STATUS);
+ if (RX_FIFO_LVL(val, sci))
+ readl(regs + S3C64XX_SPI_RX_DATA);
+ else
+ break;
+ } while (loops--);
+
+ 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);
+
+ 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);
+}
+
+static void enable_datapath(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_device *spi,
+ struct spi_transfer *xfer, int dma_mode)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ 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;
+ s3c2410_dma_config(sdd->tx_dmach, 1);
+ s3c2410_dma_enqueue(sdd->tx_dmach, (void *)sdd,
+ xfer->tx_dma, xfer->len);
+ s3c2410_dma_ctrl(sdd->tx_dmach, S3C2410_DMAOP_START);
+ } else {
+ unsigned char *buf = (unsigned char *) xfer->tx_buf;
+ int i = 0;
+ while (i < xfer->len)
+ writeb(buf[i++], regs + S3C64XX_SPI_TX_DATA);
+ }
+ }
+
+ if (xfer->rx_buf != NULL) {
+ sdd->state |= RXBUSY;
+
+ if (sci->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);
+ s3c2410_dma_config(sdd->rx_dmach, 1);
+ s3c2410_dma_enqueue(sdd->rx_dmach, (void *)sdd,
+ xfer->rx_dma, xfer->len);
+ s3c2410_dma_ctrl(sdd->rx_dmach, S3C2410_DMAOP_START);
+ }
+ }
+
+ writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
+ writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
+}
+
+static inline void enable_cs(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_device *spi)
+{
+ struct s3c64xx_spi_csinfo *cs;
+
+ if (sdd->tgl_spi != NULL) { /* If last device toggled after mssg */
+ if (sdd->tgl_spi != spi) { /* if last mssg on diff device */
+ /* Deselect the last toggled device */
+ cs = sdd->tgl_spi->controller_data;
+ cs->set_level(spi->mode & SPI_CS_HIGH ? 0 : 1);
+ }
+ sdd->tgl_spi = NULL;
+ }
+
+ cs = spi->controller_data;
+ cs->set_level(spi->mode & SPI_CS_HIGH ? 1 : 0);
+}
+
+static int wait_for_xfer(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_transfer *xfer, int dma_mode)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ void __iomem *regs = sdd->regs;
+ unsigned long val;
+ int ms;
+
+ /* millisecs to xfer 'len' bytes @ 'cur_speed' */
+ ms = xfer->len * 8 * 1000 / sdd->cur_speed;
+ ms += 5; /* some tolerance */
+
+ if (dma_mode) {
+ val = msecs_to_jiffies(ms) + 10;
+ val = wait_for_completion_timeout(&sdd->xfer_completion, val);
+ } else {
+ val = msecs_to_loops(ms);
+ do {
+ val = readl(regs + S3C64XX_SPI_STATUS);
+ } while (RX_FIFO_LVL(val, sci) < xfer->len && --val);
+ }
+
+ if (!val)
+ return -EIO;
+
+ if (dma_mode) {
+ u32 status;
+
+ /*
+ * 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 (xfer->rx_buf == NULL) {
+ val = msecs_to_loops(10);
+ status = readl(regs + S3C64XX_SPI_STATUS);
+ while ((TX_FIFO_LVL(status, sci)
+ || !S3C64XX_SPI_ST_TX_DONE(status, sci))
+ && --val) {
+ cpu_relax();
+ status = readl(regs + S3C64XX_SPI_STATUS);
+ }
+
+ if (!val)
+ return -EIO;
+ }
+ } else {
+ unsigned char *buf;
+ int i;
+
+ /* If it was only Tx */
+ if (xfer->rx_buf == NULL) {
+ sdd->state &= ~TXBUSY;
+ return 0;
+ }
+
+ i = 0;
+ buf = xfer->rx_buf;
+ while (i < xfer->len)
+ buf[i++] = readb(regs + S3C64XX_SPI_RX_DATA);
+
+ sdd->state &= ~RXBUSY;
+ }
+
+ return 0;
+}
+
+static inline void disable_cs(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_device *spi)
+{
+ struct s3c64xx_spi_csinfo *cs = spi->controller_data;
+
+ if (sdd->tgl_spi == spi)
+ sdd->tgl_spi = NULL;
+
+ cs->set_level(spi->mode & SPI_CS_HIGH ? 0 : 1);
+}
+
+static void s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ void __iomem *regs = sdd->regs;
+ u32 val;
+
+ /* Disable Clock */
+ 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;
+ break;
+ case 16:
+ val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
+ break;
+ default:
+ val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
+ break;
+ }
+ val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE; /* Always 8bits wide */
+
+ writel(val, regs + S3C64XX_SPI_MODE_CFG);
+
+ /* Configure Clock */
+ val = readl(regs + S3C64XX_SPI_CLK_CFG);
+ val &= ~S3C64XX_SPI_PSR_MASK;
+ val |= ((clk_get_rate(sci->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);
+}
+
+void s3c64xx_spi_dma_rxcb(struct s3c2410_dma_chan *chan, void *buf_id,
+ int size, enum s3c2410_dma_buffresult res)
+{
+ struct s3c64xx_spi_driver_data *sdd = buf_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ if (res == S3C2410_RES_OK)
+ sdd->state &= ~RXBUSY;
+ else
+ dev_err(&sdd->pdev->dev, "DmaAbrtRx-%d\n", size);
+
+ /* If the other done */
+ if (!(sdd->state & TXBUSY))
+ complete(&sdd->xfer_completion);
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+}
+
+void s3c64xx_spi_dma_txcb(struct s3c2410_dma_chan *chan, void *buf_id,
+ int size, enum s3c2410_dma_buffresult res)
+{
+ struct s3c64xx_spi_driver_data *sdd = buf_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ if (res == S3C2410_RES_OK)
+ sdd->state &= ~TXBUSY;
+ else
+ dev_err(&sdd->pdev->dev, "DmaAbrtTx-%d \n", size);
+
+ /* If the other done */
+ if (!(sdd->state & RXBUSY))
+ complete(&sdd->xfer_completion);
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+}
+
+#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
+
+static int s3c64xx_spi_map_mssg(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_message *msg)
+{
+ struct device *dev = &sdd->pdev->dev;
+ struct spi_transfer *xfer;
+
+ if (msg->is_dma_mapped)
+ return 0;
+
+ /* First mark all xfer unmapped */
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ xfer->rx_dma = XFER_DMAADDR_INVALID;
+ xfer->tx_dma = XFER_DMAADDR_INVALID;
+ }
+
+ /* Map until end or first fail */
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+
+ if (xfer->tx_buf != NULL) {
+ xfer->tx_dma = dma_map_single(dev, xfer->tx_buf,
+ xfer->len, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, xfer->tx_dma)) {
+ dev_err(dev, "dma_map_single Tx failed\n");
+ xfer->tx_dma = XFER_DMAADDR_INVALID;
+ return -ENOMEM;
+ }
+ }
+
+ if (xfer->rx_buf != NULL) {
+ xfer->rx_dma = dma_map_single(dev, xfer->rx_buf,
+ xfer->len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, xfer->rx_dma)) {
+ dev_err(dev, "dma_map_single Rx failed\n");
+ dma_unmap_single(dev, xfer->tx_dma,
+ xfer->len, DMA_TO_DEVICE);
+ xfer->tx_dma = XFER_DMAADDR_INVALID;
+ xfer->rx_dma = XFER_DMAADDR_INVALID;
+ return -ENOMEM;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static void s3c64xx_spi_unmap_mssg(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_message *msg)
+{
+ struct device *dev = &sdd->pdev->dev;
+ struct spi_transfer *xfer;
+
+ if (msg->is_dma_mapped)
+ return;
+
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+
+ if (xfer->rx_buf != NULL
+ && xfer->rx_dma != XFER_DMAADDR_INVALID)
+ dma_unmap_single(dev, xfer->rx_dma,
+ xfer->len, DMA_FROM_DEVICE);
+
+ if (xfer->tx_buf != NULL
+ && xfer->tx_dma != XFER_DMAADDR_INVALID)
+ dma_unmap_single(dev, xfer->tx_dma,
+ xfer->len, DMA_TO_DEVICE);
+ }
+}
+
+static void handle_msg(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_message *msg)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ struct spi_device *spi = msg->spi;
+ struct s3c64xx_spi_csinfo *cs = spi->controller_data;
+ struct spi_transfer *xfer;
+ int status = 0, cs_toggle = 0;
+ u32 speed;
+ u8 bpw;
+
+ /* 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);
+ }
+
+ /* Map all the transfers if needed */
+ if (s3c64xx_spi_map_mssg(sdd, msg)) {
+ dev_err(&spi->dev,
+ "Xfer: Unable to map message buffers!\n");
+ status = -ENOMEM;
+ goto out;
+ }
+
+ /* Configure feedback delay */
+ writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
+
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+
+ unsigned long flags;
+ int use_dma;
+
+ INIT_COMPLETION(sdd->xfer_completion);
+
+ /* Only BPW and Speed may change across transfers */
+ bpw = xfer->bits_per_word ? : spi->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 */
+ if (xfer->len <= ((sci->fifo_lvl_mask >> 1) + 1))
+ use_dma = 0;
+ else
+ 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);
+
+ /* Slave Select */
+ enable_cs(sdd, spi);
+
+ /* Start the signals */
+ S3C64XX_SPI_ACT(sdd);
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ status = wait_for_xfer(sdd, xfer, use_dma);
+
+ /* Quiese the signals */
+ S3C64XX_SPI_DEACT(sdd);
+
+ 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))
+ s3c2410_dma_ctrl(sdd->tx_dmach,
+ S3C2410_DMAOP_FLUSH);
+ if (xfer->rx_buf != NULL
+ && (sdd->state & RXBUSY))
+ s3c2410_dma_ctrl(sdd->rx_dmach,
+ S3C2410_DMAOP_FLUSH);
+ }
+
+ goto out;
+ }
+
+ if (xfer->delay_usecs)
+ udelay(xfer->delay_usecs);
+
+ if (xfer->cs_change) {
+ /* Hint that the next mssg is gonna be
+ for the same device */
+ if (list_is_last(&xfer->transfer_list,
+ &msg->transfers))
+ cs_toggle = 1;
+ else
+ disable_cs(sdd, spi);
+ }
+
+ msg->actual_length += xfer->len;
+
+ flush_fifo(sdd);
+ }
+
+out:
+ if (!cs_toggle || status)
+ disable_cs(sdd, spi);
+ else
+ sdd->tgl_spi = spi;
+
+ s3c64xx_spi_unmap_mssg(sdd, msg);
+
+ msg->status = status;
+
+ if (msg->complete)
+ msg->complete(msg->context);
+}
+
+static int acquire_dma(struct s3c64xx_spi_driver_data *sdd)
+{
+ if (s3c2410_dma_request(sdd->rx_dmach,
+ &s3c64xx_spi_dma_client, NULL) < 0) {
+ dev_err(&sdd->pdev->dev, "cannot get RxDMA\n");
+ return 0;
+ }
+ s3c2410_dma_set_buffdone_fn(sdd->rx_dmach, s3c64xx_spi_dma_rxcb);
+ s3c2410_dma_devconfig(sdd->rx_dmach, S3C2410_DMASRC_HW,
+ sdd->sfr_start + S3C64XX_SPI_RX_DATA);
+
+ if (s3c2410_dma_request(sdd->tx_dmach,
+ &s3c64xx_spi_dma_client, NULL) < 0) {
+ dev_err(&sdd->pdev->dev, "cannot get TxDMA\n");
+ s3c2410_dma_free(sdd->rx_dmach, &s3c64xx_spi_dma_client);
+ return 0;
+ }
+ s3c2410_dma_set_buffdone_fn(sdd->tx_dmach, s3c64xx_spi_dma_txcb);
+ s3c2410_dma_devconfig(sdd->tx_dmach, S3C2410_DMASRC_MEM,
+ sdd->sfr_start + S3C64XX_SPI_TX_DATA);
+
+ return 1;
+}
+
+static void s3c64xx_spi_work(struct work_struct *work)
+{
+ struct s3c64xx_spi_driver_data *sdd = container_of(work,
+ struct s3c64xx_spi_driver_data, work);
+ unsigned long flags;
+
+ /* Acquire DMA channels */
+ while (!acquire_dma(sdd))
+ msleep(10);
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ while (!list_empty(&sdd->queue)
+ && !(sdd->state & SUSPND)) {
+
+ struct spi_message *msg;
+
+ msg = container_of(sdd->queue.next, struct spi_message, queue);
+
+ list_del_init(&msg->queue);
+
+ /* Set Xfer busy flag */
+ sdd->state |= SPIBUSY;
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ handle_msg(sdd, msg);
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ sdd->state &= ~SPIBUSY;
+ }
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ /* Free DMA channels */
+ s3c2410_dma_free(sdd->tx_dmach, &s3c64xx_spi_dma_client);
+ s3c2410_dma_free(sdd->rx_dmach, &s3c64xx_spi_dma_client);
+}
+
+static int s3c64xx_spi_transfer(struct spi_device *spi,
+ struct spi_message *msg)
+{
+ struct s3c64xx_spi_driver_data *sdd;
+ unsigned long flags;
+
+ sdd = spi_master_get_devdata(spi->master);
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ if (sdd->state & SUSPND) {
+ spin_unlock_irqrestore(&sdd->lock, flags);
+ return -ESHUTDOWN;
+ }
+
+ msg->status = -EINPROGRESS;
+ msg->actual_length = 0;
+
+ list_add_tail(&msg->queue, &sdd->queue);
+
+ queue_work(sdd->workqueue, &sdd->work);
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ return 0;
+}
+
+/*
+ * 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_cntrlr_info *sci;
+ struct spi_message *msg;
+ u32 psr, speed;
+ unsigned long flags;
+ int err = 0;
+
+ if (cs == NULL || cs->set_level == NULL) {
+ dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
+ return -ENODEV;
+ }
+
+ sdd = spi_master_get_devdata(spi->master);
+ sci = sdd->cntrlr_info;
+
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ list_for_each_entry(msg, &sdd->queue, queue) {
+ /* Is some mssg is already queued for this device */
+ if (msg->spi == spi) {
+ dev_err(&spi->dev,
+ "setup: attempt while mssg in queue!\n");
+ spin_unlock_irqrestore(&sdd->lock, flags);
+ return -EBUSY;
+ }
+ }
+
+ if (sdd->state & SUSPND) {
+ spin_unlock_irqrestore(&sdd->lock, flags);
+ dev_err(&spi->dev,
+ "setup: SPI-%d not active!\n", spi->master->bus_num);
+ return -ESHUTDOWN;
+ }
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ if (spi->bits_per_word != 8
+ && spi->bits_per_word != 16
+ && spi->bits_per_word != 32) {
+ dev_err(&spi->dev, "setup: %dbits/wrd not supported!\n",
+ spi->bits_per_word);
+ err = -EINVAL;
+ goto setup_exit;
+ }
+
+ /* Check if we can provide the requested rate */
+ speed = clk_get_rate(sci->src_clk) / 2 / (0 + 1); /* Max possible */
+
+ if (spi->max_speed_hz > speed)
+ spi->max_speed_hz = speed;
+
+ psr = clk_get_rate(sci->src_clk) / 2 / spi->max_speed_hz - 1;
+ psr &= S3C64XX_SPI_PSR_MASK;
+ if (psr == S3C64XX_SPI_PSR_MASK)
+ psr--;
+
+ speed = clk_get_rate(sci->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(sci->src_clk) / 2 / (psr + 1);
+ if (spi->max_speed_hz >= speed)
+ spi->max_speed_hz = speed;
+ else
+ err = -EINVAL;
+
+setup_exit:
+
+ /* setup() returns with device de-selected */
+ disable_cs(sdd, spi);
+
+ return err;
+}
+
+static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd, int channel)
+{
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ void __iomem *regs = sdd->regs;
+ unsigned int val;
+
+ sdd->cur_speed = 0;
+
+ S3C64XX_SPI_DEACT(sdd);
+
+ /* Disable Interrupts - we use Polling if not DMA mode */
+ writel(0, regs + S3C64XX_SPI_INT_EN);
+
+ 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 */
+ writel(readl(regs + S3C64XX_SPI_PENDING_CLR),
+ 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);
+}
+
+static int __init s3c64xx_spi_probe(struct platform_device *pdev)
+{
+ struct resource *mem_res, *dmatx_res, *dmarx_res;
+ struct s3c64xx_spi_driver_data *sdd;
+ struct s3c64xx_spi_cntrlr_info *sci;
+ struct spi_master *master;
+ int ret;
+
+ if (pdev->id < 0) {
+ dev_err(&pdev->dev,
+ "Invalid platform device id-%d\n", pdev->id);
+ return -ENODEV;
+ }
+
+ if (pdev->dev.platform_data == NULL) {
+ dev_err(&pdev->dev, "platform_data missing!\n");
+ return -ENODEV;
+ }
+
+ /* Check for availability of necessary resource */
+
+ dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+ if (dmatx_res == NULL) {
+ dev_err(&pdev->dev, "Unable to get SPI-Tx dma resource\n");
+ return -ENXIO;
+ }
+
+ dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+ if (dmarx_res == NULL) {
+ dev_err(&pdev->dev, "Unable to get SPI-Rx dma resource\n");
+ return -ENXIO;
+ }
+
+ 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;
+ }
+
+ 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;
+ }
+
+ sci = pdev->dev.platform_data;
+
+ platform_set_drvdata(pdev, master);
+
+ sdd = spi_master_get_devdata(master);
+ sdd->master = master;
+ sdd->cntrlr_info = sci;
+ sdd->pdev = pdev;
+ sdd->sfr_start = mem_res->start;
+ sdd->tx_dmach = dmatx_res->start;
+ sdd->rx_dmach = dmarx_res->start;
+
+ sdd->cur_bpw = 8;
+
+ master->bus_num = pdev->id;
+ master->setup = s3c64xx_spi_setup;
+ master->transfer = s3c64xx_spi_transfer;
+ master->num_chipselect = sci->num_cs;
+ master->dma_alignment = 8;
+ /* the spi->mode bits understood by this driver: */
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+
+ if (request_mem_region(mem_res->start,
+ resource_size(mem_res), pdev->name) == NULL) {
+ dev_err(&pdev->dev, "Req mem region failed\n");
+ ret = -ENXIO;
+ goto err0;
+ }
+
+ sdd->regs = ioremap(mem_res->start, resource_size(mem_res));
+ if (sdd->regs == NULL) {
+ dev_err(&pdev->dev, "Unable to remap IO\n");
+ ret = -ENXIO;
+ goto err1;
+ }
+
+ if (sci->cfg_gpio == NULL || sci->cfg_gpio(pdev)) {
+ dev_err(&pdev->dev, "Unable to config gpio\n");
+ ret = -EBUSY;
+ goto err2;
+ }
+
+ /* Setup clocks */
+ sdd->clk = 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 err3;
+ }
+
+ if (clk_enable(sdd->clk)) {
+ dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
+ ret = -EBUSY;
+ goto err4;
+ }
+
+ if (sci->src_clk_nr == S3C64XX_SPI_SRCCLK_PCLK)
+ sci->src_clk = sdd->clk;
+ else
+ sci->src_clk = clk_get(&pdev->dev, sci->src_clk_name);
+ if (IS_ERR(sci->src_clk)) {
+ dev_err(&pdev->dev,
+ "Unable to acquire clock '%s'\n", sci->src_clk_name);
+ ret = PTR_ERR(sci->src_clk);
+ goto err5;
+ }
+
+ if (sci->src_clk != sdd->clk && clk_enable(sci->src_clk)) {
+ dev_err(&pdev->dev, "Couldn't enable clock '%s'\n",
+ sci->src_clk_name);
+ ret = -EBUSY;
+ goto err6;
+ }
+
+ sdd->workqueue = create_singlethread_workqueue(
+ dev_name(master->dev.parent));
+ if (sdd->workqueue == NULL) {
+ dev_err(&pdev->dev, "Unable to create workqueue\n");
+ ret = -ENOMEM;
+ goto err7;
+ }
+
+ /* Setup Deufult Mode */
+ s3c64xx_spi_hwinit(sdd, pdev->id);
+
+ spin_lock_init(&sdd->lock);
+ init_completion(&sdd->xfer_completion);
+ INIT_WORK(&sdd->work, s3c64xx_spi_work);
+ INIT_LIST_HEAD(&sdd->queue);
+
+ if (spi_register_master(master)) {
+ dev_err(&pdev->dev, "cannot register SPI master\n");
+ ret = -EBUSY;
+ goto err8;
+ }
+
+ dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d \
+ with %d Slaves attached\n",
+ pdev->id, master->num_chipselect);
+ dev_dbg(&pdev->dev, "\tIOmem=[0x%x-0x%x]\
+ \tDMA=[Rx-%d, Tx-%d]\n",
+ mem_res->end, mem_res->start,
+ sdd->rx_dmach, sdd->tx_dmach);
+
+ return 0;
+
+err8:
+ destroy_workqueue(sdd->workqueue);
+err7:
+ if (sci->src_clk != sdd->clk)
+ clk_disable(sci->src_clk);
+err6:
+ if (sci->src_clk != sdd->clk)
+ clk_put(sci->src_clk);
+err5:
+ clk_disable(sdd->clk);
+err4:
+ clk_put(sdd->clk);
+err3:
+err2:
+ iounmap((void *) sdd->regs);
+err1:
+ release_mem_region(mem_res->start, resource_size(mem_res));
+err0:
+ platform_set_drvdata(pdev, NULL);
+ 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);
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ struct resource *mem_res;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sdd->lock, flags);
+ sdd->state |= SUSPND;
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ while (sdd->state & SPIBUSY)
+ msleep(10);
+
+ spi_unregister_master(master);
+
+ destroy_workqueue(sdd->workqueue);
+
+ if (sci->src_clk != sdd->clk)
+ clk_disable(sci->src_clk);
+
+ if (sci->src_clk != sdd->clk)
+ clk_put(sci->src_clk);
+
+ clk_disable(sdd->clk);
+ clk_put(sdd->clk);
+
+ iounmap((void *) sdd->regs);
+
+ mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(mem_res->start, resource_size(mem_res));
+
+ platform_set_drvdata(pdev, NULL);
+ spi_master_put(master);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int s3c64xx_spi_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ struct s3c64xx_spi_csinfo *cs;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sdd->lock, flags);
+ sdd->state |= SUSPND;
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ while (sdd->state & SPIBUSY)
+ msleep(10);
+
+ /* Disable the clock */
+ if (sci->src_clk != sdd->clk)
+ clk_disable(sci->src_clk);
+
+ clk_disable(sdd->clk);
+
+ sdd->cur_speed = 0; /* Output Clock is stopped */
+
+ return 0;
+}
+
+static int s3c64xx_spi_resume(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);
+ struct s3c64xx_spi_cntrlr_info *sci = sdd->cntrlr_info;
+ unsigned long flags;
+
+ sci->cfg_gpio(pdev);
+
+ /* Enable the clock */
+ if (sci->src_clk != sdd->clk)
+ clk_enable(sci->src_clk);
+
+ clk_enable(sdd->clk);
+
+ s3c64xx_spi_hwinit(sdd, pdev->id);
+
+ spin_lock_irqsave(&sdd->lock, flags);
+ sdd->state &= ~SUSPND;
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ return 0;
+}
+#else
+#define s3c64xx_spi_suspend NULL
+#define s3c64xx_spi_resume NULL
+#endif /* CONFIG_PM */
+
+static struct platform_driver s3c64xx_spi_driver = {
+ .driver = {
+ .name = "s3c64xx-spi",
+ .owner = THIS_MODULE,
+ },
+ .remove = s3c64xx_spi_remove,
+ .suspend = s3c64xx_spi_suspend,
+ .resume = s3c64xx_spi_resume,
+};
+MODULE_ALIAS("platform:s3c64xx-spi");
+
+static int __init s3c64xx_spi_init(void)
+{
+ return platform_driver_probe(&s3c64xx_spi_driver, s3c64xx_spi_probe);
+}
+module_init(s3c64xx_spi_init);
+
+static void __exit s3c64xx_spi_exit(void)
+{
+ platform_driver_unregister(&s3c64xx_spi_driver);
+}
+module_exit(s3c64xx_spi_exit);
+
+MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
+MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
+MODULE_LICENSE("GPL");
projects / openwrt / staging / blogic.git / commitdiff