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-rw-r--r--drivers/spi/spi-s3c64xx.c1509
1 files changed, 1509 insertions, 0 deletions
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
new file mode 100644
index 000000000..d435df1b7
--- /dev/null
+++ b/drivers/spi/spi-s3c64xx.c
@@ -0,0 +1,1509 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (c) 2009 Samsung Electronics Co., Ltd.
+// Jaswinder Singh <jassi.brar@samsung.com>
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+
+#include <linux/platform_data/spi-s3c64xx.h>
+
+#define MAX_SPI_PORTS 6
+#define S3C64XX_SPI_QUIRK_POLL (1 << 0)
+#define S3C64XX_SPI_QUIRK_CS_AUTO (1 << 1)
+#define AUTOSUSPEND_TIMEOUT 2000
+
+/* 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_CS_REG 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_CS_NSC_CNT_2 (2<<4)
+#define S3C64XX_SPI_CS_AUTO (1<<1)
+#define S3C64XX_SPI_CS_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_PACKET_CNT_MASK GENMASK(15, 0)
+
+#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;
+ dma_cookie_t cookie;
+ enum dma_transfer_direction direction;
+};
+
+/**
+ * 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.
+ * @quirks: Bitmask of known quirks
+ * @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.
+ * @clk_ioclk: True if clock is present on this device
+ *
+ * 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;
+ bool clk_ioclk;
+};
+
+/**
+ * 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.
+ * @ioclk: Pointer to the i/o clock between master and slave
+ * @pdev: Pointer to device's platform device data
+ * @master: Pointer to the SPI Protocol master.
+ * @cntrlr_info: Platform specific data for the controller this driver manages.
+ * @lock: Controller specific lock.
+ * @state: Set of FLAGS to indicate status.
+ * @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: Current clock speed
+ * @rx_dma: Local receive DMA data (e.g. chan and direction)
+ * @tx_dma: Local transmit DMA data (e.g. chan and direction)
+ * @port_conf: Local SPI port configuartion data
+ * @port_id: Port identification number
+ */
+struct s3c64xx_spi_driver_data {
+ void __iomem *regs;
+ struct clk *clk;
+ struct clk *src_clk;
+ struct clk *ioclk;
+ struct platform_device *pdev;
+ struct spi_master *master;
+ struct s3c64xx_spi_info *cntrlr_info;
+ 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;
+};
+
+static void s3c64xx_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 int 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;
+ int ret;
+
+ 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);
+ if (!desc) {
+ dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
+ dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
+ return -ENOMEM;
+ }
+
+ desc->callback = s3c64xx_spi_dmacb;
+ desc->callback_param = dma;
+
+ dma->cookie = dmaengine_submit(desc);
+ ret = dma_submit_error(dma->cookie);
+ if (ret) {
+ dev_err(&sdd->pdev->dev, "DMA submission failed");
+ return -EIO;
+ }
+
+ dma_async_issue_pending(dma->ch);
+ return 0;
+}
+
+static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct s3c64xx_spi_driver_data *sdd =
+ spi_master_get_devdata(spi->master);
+
+ if (sdd->cntrlr_info->no_cs)
+ return;
+
+ if (enable) {
+ if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
+ writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
+ } else {
+ u32 ssel = readl(sdd->regs + S3C64XX_SPI_CS_REG);
+
+ ssel |= (S3C64XX_SPI_CS_AUTO |
+ S3C64XX_SPI_CS_NSC_CNT_2);
+ writel(ssel, sdd->regs + S3C64XX_SPI_CS_REG);
+ }
+ } else {
+ if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
+ writel(S3C64XX_SPI_CS_SIG_INACT,
+ sdd->regs + S3C64XX_SPI_CS_REG);
+ }
+}
+
+static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
+{
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
+
+ if (is_polling(sdd))
+ return 0;
+
+ spi->dma_rx = sdd->rx_dma.ch;
+ spi->dma_tx = sdd->tx_dma.ch;
+
+ 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 int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
+ struct spi_transfer *xfer, int dma_mode)
+{
+ void __iomem *regs = sdd->regs;
+ u32 modecfg, chcfg;
+ int ret = 0;
+
+ 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;
+ ret = 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);
+ ret = prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
+ }
+ }
+
+ if (ret)
+ return ret;
+
+ writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
+ writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
+
+ return 0;
+}
+
+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 s3c64xx_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 += 30; /* some tolerance */
+ ms = max(ms, 100); /* minimum timeout */
+
+ 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 s3c64xx_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 (!val)
+ return -EIO;
+
+ /* 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 int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
+{
+ void __iomem *regs = sdd->regs;
+ int ret;
+ u32 val;
+
+ /* Disable Clock */
+ if (!sdd->port_conf->clk_from_cmu) {
+ 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) {
+ /* The src_clk clock is divided internally by 2 */
+ ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
+ if (ret)
+ return ret;
+ sdd->cur_speed = clk_get_rate(sdd->src_clk) / 2;
+ } 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);
+ }
+
+ return 0;
+}
+
+#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;
+
+ /* Configure feedback delay */
+ writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
+
+ return 0;
+}
+
+static size_t s3c64xx_spi_max_transfer_size(struct spi_device *spi)
+{
+ struct spi_controller *ctlr = spi->controller;
+
+ return ctlr->can_dma ? S3C64XX_SPI_PACKET_CNT_MASK : SIZE_MAX;
+}
+
+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);
+ const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
+ const void *tx_buf = NULL;
+ void *rx_buf = NULL;
+ int target_len = 0, origin_len = 0;
+ int use_dma = 0;
+ int status;
+ u32 speed;
+ u8 bpw;
+ unsigned long flags;
+
+ reinit_completion(&sdd->xfer_completion);
+
+ /* Only BPW and Speed may change across transfers */
+ bpw = xfer->bits_per_word;
+ speed = xfer->speed_hz;
+
+ if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
+ sdd->cur_bpw = bpw;
+ sdd->cur_speed = speed;
+ sdd->cur_mode = spi->mode;
+ status = s3c64xx_spi_config(sdd);
+ if (status)
+ return status;
+ }
+
+ if (!is_polling(sdd) && (xfer->len > fifo_len) &&
+ sdd->rx_dma.ch && sdd->tx_dma.ch) {
+ use_dma = 1;
+
+ } else if (is_polling(sdd) && xfer->len > fifo_len) {
+ tx_buf = xfer->tx_buf;
+ rx_buf = xfer->rx_buf;
+ origin_len = xfer->len;
+
+ target_len = xfer->len;
+ if (xfer->len > fifo_len)
+ xfer->len = fifo_len;
+ }
+
+ do {
+ spin_lock_irqsave(&sdd->lock, flags);
+
+ /* Pending only which is to be done */
+ sdd->state &= ~RXBUSY;
+ sdd->state &= ~TXBUSY;
+
+ /* Start the signals */
+ s3c64xx_spi_set_cs(spi, true);
+
+ status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
+
+ spin_unlock_irqrestore(&sdd->lock, flags);
+
+ if (status) {
+ dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
+ break;
+ }
+
+ if (use_dma)
+ status = s3c64xx_wait_for_dma(sdd, xfer);
+ else
+ status = s3c64xx_wait_for_pio(sdd, xfer);
+
+ if (status) {
+ dev_err(&spi->dev,
+ "I/O Error: rx-%d tx-%d rx-%c tx-%c len-%d dma-%d res-(%d)\n",
+ xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
+ (sdd->state & RXBUSY) ? 'f' : 'p',
+ (sdd->state & TXBUSY) ? 'f' : 'p',
+ xfer->len, use_dma ? 1 : 0, status);
+
+ if (use_dma) {
+ struct dma_tx_state s;
+
+ if (xfer->tx_buf && (sdd->state & TXBUSY)) {
+ dmaengine_pause(sdd->tx_dma.ch);
+ dmaengine_tx_status(sdd->tx_dma.ch, sdd->tx_dma.cookie, &s);
+ dmaengine_terminate_all(sdd->tx_dma.ch);
+ dev_err(&spi->dev, "TX residue: %d\n", s.residue);
+
+ }
+ if (xfer->rx_buf && (sdd->state & RXBUSY)) {
+ dmaengine_pause(sdd->rx_dma.ch);
+ dmaengine_tx_status(sdd->rx_dma.ch, sdd->rx_dma.cookie, &s);
+ dmaengine_terminate_all(sdd->rx_dma.ch);
+ dev_err(&spi->dev, "RX residue: %d\n", s.residue);
+ }
+ }
+ } else {
+ s3c64xx_flush_fifo(sdd);
+ }
+ if (target_len > 0) {
+ target_len -= xfer->len;
+
+ if (xfer->tx_buf)
+ xfer->tx_buf += xfer->len;
+
+ if (xfer->rx_buf)
+ xfer->rx_buf += xfer->len;
+
+ if (target_len > fifo_len)
+ xfer->len = fifo_len;
+ else
+ xfer->len = target_len;
+ }
+ } while (target_len > 0);
+
+ if (origin_len) {
+ /* Restore original xfer buffers and length */
+ xfer->tx_buf = tx_buf;
+ xfer->rx_buf = rx_buf;
+ xfer->len = origin_len;
+ }
+
+ 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;
+ u32 fb_delay = 0;
+
+ 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);
+ }
+
+ 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;
+ int err;
+
+ sdd = spi_master_get_devdata(spi->master);
+ if (spi->dev.of_node) {
+ cs = s3c64xx_get_slave_ctrldata(spi);
+ spi->controller_data = cs;
+ } else if (cs) {
+ /* On non-DT platforms the SPI core will set spi->cs_gpio
+ * to -ENOENT. The GPIO pin used to drive the chip select
+ * is defined by using platform data so spi->cs_gpio value
+ * has to be override to have the proper GPIO pin number.
+ */
+ spi->cs_gpio = cs->line;
+ }
+
+ 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)) {
+ if (gpio_is_valid(spi->cs_gpio)) {
+ err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
+ dev_name(&spi->dev));
+ if (err) {
+ dev_err(&spi->dev,
+ "Failed to get /CS gpio [%d]: %d\n",
+ spi->cs_gpio, err);
+ goto err_gpio_req;
+ }
+ }
+
+ spi_set_ctldata(spi, cs);
+ }
+
+ 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_mark_last_busy(&sdd->pdev->dev);
+ pm_runtime_put_autosuspend(&sdd->pdev->dev);
+ s3c64xx_spi_set_cs(spi, false);
+
+ return 0;
+
+setup_exit:
+ pm_runtime_mark_last_busy(&sdd->pdev->dev);
+ pm_runtime_put_autosuspend(&sdd->pdev->dev);
+ /* setup() returns with device de-selected */
+ s3c64xx_spi_set_cs(spi, false);
+
+ if (gpio_is_valid(spi->cs_gpio))
+ gpio_free(spi->cs_gpio);
+ 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);
+
+ if (gpio_is_valid(spi->cs_gpio)) {
+ gpio_free(spi->cs_gpio);
+ if (spi->dev.of_node)
+ kfree(cs);
+ else {
+ /* On non-DT platforms, the SPI core sets
+ * spi->cs_gpio to -ENOENT and .setup()
+ * overrides it with the GPIO pin value
+ * passed using platform data.
+ */
+ spi->cs_gpio = -ENOENT;
+ }
+ }
+
+ 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)
+{
+ struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
+ void __iomem *regs = sdd->regs;
+ unsigned int val;
+
+ sdd->cur_speed = 0;
+
+ if (sci->no_cs)
+ writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
+ else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
+ writel(S3C64XX_SPI_CS_SIG_INACT, sdd->regs + S3C64XX_SPI_CS_REG);
+
+ /* 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);
+
+ s3c64xx_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;
+ }
+
+ sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
+
+ 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 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;
+ if (pdev->dev.of_node) {
+ 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 err_deref_master;
+ }
+ sdd->port_id = ret;
+ } else {
+ sdd->port_id = pdev->id;
+ }
+
+ sdd->cur_bpw = 8;
+
+ 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->max_transfer_size = s3c64xx_spi_max_transfer_size;
+ 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 err_deref_master;
+ }
+
+ if (sci->cfg_gpio && sci->cfg_gpio()) {
+ dev_err(&pdev->dev, "Unable to config gpio\n");
+ ret = -EBUSY;
+ goto err_deref_master;
+ }
+
+ /* 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 err_deref_master;
+ }
+
+ ret = clk_prepare_enable(sdd->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
+ goto err_deref_master;
+ }
+
+ 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 err_disable_clk;
+ }
+
+ ret = clk_prepare_enable(sdd->src_clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
+ goto err_disable_clk;
+ }
+
+ if (sdd->port_conf->clk_ioclk) {
+ sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
+ if (IS_ERR(sdd->ioclk)) {
+ dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
+ ret = PTR_ERR(sdd->ioclk);
+ goto err_disable_src_clk;
+ }
+
+ ret = clk_prepare_enable(sdd->ioclk);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
+ goto err_disable_src_clk;
+ }
+ }
+
+ if (!is_polling(sdd)) {
+ /* Acquire DMA channels */
+ sdd->rx_dma.ch = dma_request_chan(&pdev->dev, "rx");
+ if (IS_ERR(sdd->rx_dma.ch)) {
+ dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
+ ret = PTR_ERR(sdd->rx_dma.ch);
+ goto err_disable_io_clk;
+ }
+ sdd->tx_dma.ch = dma_request_chan(&pdev->dev, "tx");
+ if (IS_ERR(sdd->tx_dma.ch)) {
+ dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
+ ret = PTR_ERR(sdd->tx_dma.ch);
+ goto err_release_rx_dma;
+ }
+ }
+
+ pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+
+ /* Setup Deufult Mode */
+ s3c64xx_spi_hwinit(sdd);
+
+ 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 err_pm_put;
+ }
+
+ 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);
+
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
+ goto err_pm_put;
+ }
+
+ 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]\tFIFO %dbytes\n",
+ mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
+ return 0;
+
+err_pm_put:
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+
+ if (!is_polling(sdd))
+ dma_release_channel(sdd->tx_dma.ch);
+err_release_rx_dma:
+ if (!is_polling(sdd))
+ dma_release_channel(sdd->rx_dma.ch);
+err_disable_io_clk:
+ clk_disable_unprepare(sdd->ioclk);
+err_disable_src_clk:
+ clk_disable_unprepare(sdd->src_clk);
+err_disable_clk:
+ clk_disable_unprepare(sdd->clk);
+err_deref_master:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int s3c64xx_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+ pm_runtime_get_sync(&pdev->dev);
+
+ writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
+
+ if (!is_polling(sdd)) {
+ dma_release_channel(sdd->rx_dma.ch);
+ dma_release_channel(sdd->tx_dma.ch);
+ }
+
+ clk_disable_unprepare(sdd->ioclk);
+
+ clk_disable_unprepare(sdd->src_clk);
+
+ clk_disable_unprepare(sdd->clk);
+
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+
+ 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;
+
+ ret = pm_runtime_force_suspend(dev);
+ if (ret < 0)
+ return ret;
+
+ 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;
+ int ret;
+
+ if (sci->cfg_gpio)
+ sci->cfg_gpio();
+
+ ret = pm_runtime_force_resume(dev);
+ if (ret < 0)
+ return ret;
+
+ return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+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);
+ clk_disable_unprepare(sdd->ioclk);
+
+ 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;
+
+ if (sdd->port_conf->clk_ioclk) {
+ ret = clk_prepare_enable(sdd->ioclk);
+ if (ret != 0)
+ return ret;
+ }
+
+ ret = clk_prepare_enable(sdd->src_clk);
+ if (ret != 0)
+ goto err_disable_ioclk;
+
+ ret = clk_prepare_enable(sdd->clk);
+ if (ret != 0)
+ goto err_disable_src_clk;
+
+ s3c64xx_spi_hwinit(sdd);
+
+ 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);
+
+ return 0;
+
+err_disable_src_clk:
+ clk_disable_unprepare(sdd->src_clk);
+err_disable_ioclk:
+ clk_disable_unprepare(sdd->ioclk);
+
+ return ret;
+}
+#endif /* CONFIG_PM */
+
+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,
+ .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
+ .fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
+ .rx_lvl_offset = 15,
+ .tx_st_done = 25,
+ .high_speed = true,
+ .clk_from_cmu = true,
+ .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
+ .fifo_lvl_mask = { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
+ .rx_lvl_offset = 15,
+ .tx_st_done = 25,
+ .high_speed = true,
+ .clk_from_cmu = true,
+ .clk_ioclk = true,
+ .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static const 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,
+ },
+ { },
+};
+
+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,exynos7-spi",
+ .data = (void *)&exynos7_spi_port_config,
+ },
+ { .compatible = "samsung,exynos5433-spi",
+ .data = (void *)&exynos5433_spi_port_config,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
+
+static struct platform_driver s3c64xx_spi_driver = {
+ .driver = {
+ .name = "s3c64xx-spi",
+ .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 <jassi.brar@samsung.com>");
+MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
+MODULE_LICENSE("GPL");