--- /dev/null
+/*
+ * SPI bus driver for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/of_gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/reset.h>
+
+#define DRIVER_NAME "sirfsoc_spi"
+
+#define SIRFSOC_SPI_CTRL 0x0000
+#define SIRFSOC_SPI_CMD 0x0004
+#define SIRFSOC_SPI_TX_RX_EN 0x0008
+#define SIRFSOC_SPI_INT_EN 0x000C
+#define SIRFSOC_SPI_INT_STATUS 0x0010
+#define SIRFSOC_SPI_TX_DMA_IO_CTRL 0x0100
+#define SIRFSOC_SPI_TX_DMA_IO_LEN 0x0104
+#define SIRFSOC_SPI_TXFIFO_CTRL 0x0108
+#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK 0x010C
+#define SIRFSOC_SPI_TXFIFO_OP 0x0110
+#define SIRFSOC_SPI_TXFIFO_STATUS 0x0114
+#define SIRFSOC_SPI_TXFIFO_DATA 0x0118
+#define SIRFSOC_SPI_RX_DMA_IO_CTRL 0x0120
+#define SIRFSOC_SPI_RX_DMA_IO_LEN 0x0124
+#define SIRFSOC_SPI_RXFIFO_CTRL 0x0128
+#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK 0x012C
+#define SIRFSOC_SPI_RXFIFO_OP 0x0130
+#define SIRFSOC_SPI_RXFIFO_STATUS 0x0134
+#define SIRFSOC_SPI_RXFIFO_DATA 0x0138
+#define SIRFSOC_SPI_DUMMY_DELAY_CTL 0x0144
+
+/* SPI CTRL register defines */
+#define SIRFSOC_SPI_SLV_MODE BIT(16)
+#define SIRFSOC_SPI_CMD_MODE BIT(17)
+#define SIRFSOC_SPI_CS_IO_OUT BIT(18)
+#define SIRFSOC_SPI_CS_IO_MODE BIT(19)
+#define SIRFSOC_SPI_CLK_IDLE_STAT BIT(20)
+#define SIRFSOC_SPI_CS_IDLE_STAT BIT(21)
+#define SIRFSOC_SPI_TRAN_MSB BIT(22)
+#define SIRFSOC_SPI_DRV_POS_EDGE BIT(23)
+#define SIRFSOC_SPI_CS_HOLD_TIME BIT(24)
+#define SIRFSOC_SPI_CLK_SAMPLE_MODE BIT(25)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8 (0 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12 (1 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16 (2 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32 (3 << 26)
+#define SIRFSOC_SPI_CMD_BYTE_NUM(x) ((x & 3) << 28)
+#define SIRFSOC_SPI_ENA_AUTO_CLR BIT(30)
+#define SIRFSOC_SPI_MUL_DAT_MODE BIT(31)
+
+/* Interrupt Enable */
+#define SIRFSOC_SPI_RX_DONE_INT_EN BIT(0)
+#define SIRFSOC_SPI_TX_DONE_INT_EN BIT(1)
+#define SIRFSOC_SPI_RX_OFLOW_INT_EN BIT(2)
+#define SIRFSOC_SPI_TX_UFLOW_INT_EN BIT(3)
+#define SIRFSOC_SPI_RX_IO_DMA_INT_EN BIT(4)
+#define SIRFSOC_SPI_TX_IO_DMA_INT_EN BIT(5)
+#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN BIT(6)
+#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN BIT(7)
+#define SIRFSOC_SPI_RXFIFO_THD_INT_EN BIT(8)
+#define SIRFSOC_SPI_TXFIFO_THD_INT_EN BIT(9)
+#define SIRFSOC_SPI_FRM_END_INT_EN BIT(10)
+
+#define SIRFSOC_SPI_INT_MASK_ALL 0x1FFF
+
+/* Interrupt status */
+#define SIRFSOC_SPI_RX_DONE BIT(0)
+#define SIRFSOC_SPI_TX_DONE BIT(1)
+#define SIRFSOC_SPI_RX_OFLOW BIT(2)
+#define SIRFSOC_SPI_TX_UFLOW BIT(3)
+#define SIRFSOC_SPI_RX_IO_DMA BIT(4)
+#define SIRFSOC_SPI_RX_FIFO_FULL BIT(6)
+#define SIRFSOC_SPI_TXFIFO_EMPTY BIT(7)
+#define SIRFSOC_SPI_RXFIFO_THD_REACH BIT(8)
+#define SIRFSOC_SPI_TXFIFO_THD_REACH BIT(9)
+#define SIRFSOC_SPI_FRM_END BIT(10)
+
+/* TX RX enable */
+#define SIRFSOC_SPI_RX_EN BIT(0)
+#define SIRFSOC_SPI_TX_EN BIT(1)
+#define SIRFSOC_SPI_CMD_TX_EN BIT(2)
+
+#define SIRFSOC_SPI_IO_MODE_SEL BIT(0)
+#define SIRFSOC_SPI_RX_DMA_FLUSH BIT(2)
+
+/* FIFO OPs */
+#define SIRFSOC_SPI_FIFO_RESET BIT(0)
+#define SIRFSOC_SPI_FIFO_START BIT(1)
+
+/* FIFO CTRL */
+#define SIRFSOC_SPI_FIFO_WIDTH_BYTE (0 << 0)
+#define SIRFSOC_SPI_FIFO_WIDTH_WORD (1 << 0)
+#define SIRFSOC_SPI_FIFO_WIDTH_DWORD (2 << 0)
+
+/* FIFO Status */
+#define SIRFSOC_SPI_FIFO_LEVEL_MASK 0xFF
+#define SIRFSOC_SPI_FIFO_FULL BIT(8)
+#define SIRFSOC_SPI_FIFO_EMPTY BIT(9)
+
+/* 256 bytes rx/tx FIFO */
+#define SIRFSOC_SPI_FIFO_SIZE 256
+#define SIRFSOC_SPI_DAT_FRM_LEN_MAX (64 * 1024)
+
+#define SIRFSOC_SPI_FIFO_SC(x) ((x) & 0x3F)
+#define SIRFSOC_SPI_FIFO_LC(x) (((x) & 0x3F) << 10)
+#define SIRFSOC_SPI_FIFO_HC(x) (((x) & 0x3F) << 20)
+#define SIRFSOC_SPI_FIFO_THD(x) (((x) & 0xFF) << 2)
+
+/*
+ * only if the rx/tx buffer and transfer size are 4-bytes aligned, we use dma
+ * due to the limitation of dma controller
+ */
+
+#define ALIGNED(x) (!((u32)x & 0x3))
+#define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \
+ ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE))
+
+#define SIRFSOC_MAX_CMD_BYTES 4
+#define SIRFSOC_SPI_DEFAULT_FRQ 1000000
+
+struct sirfsoc_spi {
+ struct spi_bitbang bitbang;
+ struct completion rx_done;
+ struct completion tx_done;
+
+ void __iomem *base;
+ u32 ctrl_freq; /* SPI controller clock speed */
+ struct clk *clk;
+
+ /* rx & tx bufs from the spi_transfer */
+ const void *tx;
+ void *rx;
+
+ /* place received word into rx buffer */
+ void (*rx_word) (struct sirfsoc_spi *);
+ /* get word from tx buffer for sending */
+ void (*tx_word) (struct sirfsoc_spi *);
+
+ /* number of words left to be tranmitted/received */
+ unsigned int left_tx_word;
+ unsigned int left_rx_word;
+
+ /* rx & tx DMA channels */
+ struct dma_chan *rx_chan;
+ struct dma_chan *tx_chan;
+ dma_addr_t src_start;
+ dma_addr_t dst_start;
+ void *dummypage;
+ int word_width; /* in bytes */
+
+ /*
+ * if tx size is not more than 4 and rx size is NULL, use
+ * command model
+ */
+ bool tx_by_cmd;
+ bool hw_cs;
+};
+
+static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
+{
+ u32 data;
+ u8 *rx = sspi->rx;
+
+ data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+ if (rx) {
+ *rx++ = (u8) data;
+ sspi->rx = rx;
+ }
+
+ sspi->left_rx_word--;
+}
+
+static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
+{
+ u32 data = 0;
+ const u8 *tx = sspi->tx;
+
+ if (tx) {
+ data = *tx++;
+ sspi->tx = tx;
+ }
+
+ writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+ sspi->left_tx_word--;
+}
+
+static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
+{
+ u32 data;
+ u16 *rx = sspi->rx;
+
+ data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+ if (rx) {
+ *rx++ = (u16) data;
+ sspi->rx = rx;
+ }
+
+ sspi->left_rx_word--;
+}
+
+static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
+{
+ u32 data = 0;
+ const u16 *tx = sspi->tx;
+
+ if (tx) {
+ data = *tx++;
+ sspi->tx = tx;
+ }
+
+ writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+ sspi->left_tx_word--;
+}
+
+static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
+{
+ u32 data;
+ u32 *rx = sspi->rx;
+
+ data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+ if (rx) {
+ *rx++ = (u32) data;
+ sspi->rx = rx;
+ }
+
+ sspi->left_rx_word--;
+
+}
+
+static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
+{
+ u32 data = 0;
+ const u32 *tx = sspi->tx;
+
+ if (tx) {
+ data = *tx++;
+ sspi->tx = tx;
+ }
+
+ writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+ sspi->left_tx_word--;
+}
+
+static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
+{
+ struct sirfsoc_spi *sspi = dev_id;
+ u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);
+ if (sspi->tx_by_cmd && (spi_stat & SIRFSOC_SPI_FRM_END)) {
+ complete(&sspi->tx_done);
+ writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_INT_MASK_ALL,
+ sspi->base + SIRFSOC_SPI_INT_STATUS);
+ return IRQ_HANDLED;
+ }
+
+ /* Error Conditions */
+ if (spi_stat & SIRFSOC_SPI_RX_OFLOW ||
+ spi_stat & SIRFSOC_SPI_TX_UFLOW) {
+ complete(&sspi->tx_done);
+ complete(&sspi->rx_done);
+ writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_INT_MASK_ALL,
+ sspi->base + SIRFSOC_SPI_INT_STATUS);
+ return IRQ_HANDLED;
+ }
+ if (spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY)
+ complete(&sspi->tx_done);
+ while (!(readl(sspi->base + SIRFSOC_SPI_INT_STATUS) &
+ SIRFSOC_SPI_RX_IO_DMA))
+ cpu_relax();
+ complete(&sspi->rx_done);
+ writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_INT_MASK_ALL,
+ sspi->base + SIRFSOC_SPI_INT_STATUS);
+
+ return IRQ_HANDLED;
+}
+
+static void spi_sirfsoc_dma_fini_callback(void *data)
+{
+ struct completion *dma_complete = data;
+
+ complete(dma_complete);
+}
+
+static void spi_sirfsoc_cmd_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct sirfsoc_spi *sspi;
+ int timeout = t->len * 10;
+ u32 cmd;
+
+ sspi = spi_master_get_devdata(spi->master);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ memcpy(&cmd, sspi->tx, t->len);
+ if (sspi->word_width == 1 && !(spi->mode & SPI_LSB_FIRST))
+ cmd = cpu_to_be32(cmd) >>
+ ((SIRFSOC_MAX_CMD_BYTES - t->len) * 8);
+ if (sspi->word_width == 2 && t->len == 4 &&
+ (!(spi->mode & SPI_LSB_FIRST)))
+ cmd = ((cmd & 0xffff) << 16) | (cmd >> 16);
+ writel(cmd, sspi->base + SIRFSOC_SPI_CMD);
+ writel(SIRFSOC_SPI_FRM_END_INT_EN,
+ sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_CMD_TX_EN,
+ sspi->base + SIRFSOC_SPI_TX_RX_EN);
+ if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) {
+ dev_err(&spi->dev, "cmd transfer timeout\n");
+ return;
+ }
+ sspi->left_rx_word -= t->len;
+}
+
+static void spi_sirfsoc_dma_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct sirfsoc_spi *sspi;
+ struct dma_async_tx_descriptor *rx_desc, *tx_desc;
+ int timeout = t->len * 10;
+
+ sspi = spi_master_get_devdata(spi->master);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
+ if (sspi->left_tx_word < SIRFSOC_SPI_DAT_FRM_LEN_MAX) {
+ writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
+ SIRFSOC_SPI_ENA_AUTO_CLR | SIRFSOC_SPI_MUL_DAT_MODE,
+ sspi->base + SIRFSOC_SPI_CTRL);
+ writel(sspi->left_tx_word - 1,
+ sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+ writel(sspi->left_tx_word - 1,
+ sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+ } else {
+ writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
+ sspi->base + SIRFSOC_SPI_CTRL);
+ writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+ writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+ }
+ sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len,
+ (t->tx_buf != t->rx_buf) ?
+ DMA_FROM_DEVICE : DMA_BIDIRECTIONAL);
+ rx_desc = dmaengine_prep_slave_single(sspi->rx_chan,
+ sspi->dst_start, t->len, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ rx_desc->callback = spi_sirfsoc_dma_fini_callback;
+ rx_desc->callback_param = &sspi->rx_done;
+
+ sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len,
+ (t->tx_buf != t->rx_buf) ?
+ DMA_TO_DEVICE : DMA_BIDIRECTIONAL);
+ tx_desc = dmaengine_prep_slave_single(sspi->tx_chan,
+ sspi->src_start, t->len, DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ tx_desc->callback = spi_sirfsoc_dma_fini_callback;
+ tx_desc->callback_param = &sspi->tx_done;
+
+ dmaengine_submit(tx_desc);
+ dmaengine_submit(rx_desc);
+ dma_async_issue_pending(sspi->tx_chan);
+ dma_async_issue_pending(sspi->rx_chan);
+ writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN,
+ sspi->base + SIRFSOC_SPI_TX_RX_EN);
+ if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0) {
+ dev_err(&spi->dev, "transfer timeout\n");
+ dmaengine_terminate_all(sspi->rx_chan);
+ } else
+ sspi->left_rx_word = 0;
+ /*
+ * we only wait tx-done event if transferring by DMA. for PIO,
+ * we get rx data by writing tx data, so if rx is done, tx has
+ * done earlier
+ */
+ if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) {
+ dev_err(&spi->dev, "transfer timeout\n");
+ dmaengine_terminate_all(sspi->tx_chan);
+ }
+ dma_unmap_single(&spi->dev, sspi->src_start, t->len, DMA_TO_DEVICE);
+ dma_unmap_single(&spi->dev, sspi->dst_start, t->len, DMA_FROM_DEVICE);
+ /* TX, RX FIFO stop */
+ writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ if (sspi->left_tx_word >= SIRFSOC_SPI_DAT_FRM_LEN_MAX)
+ writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
+}
+
+static void spi_sirfsoc_pio_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct sirfsoc_spi *sspi;
+ int timeout = t->len * 10;
+
+ sspi = spi_master_get_devdata(spi->master);
+ do {
+ writel(SIRFSOC_SPI_FIFO_RESET,
+ sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_RESET,
+ sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START,
+ sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START,
+ sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_INT_MASK_ALL,
+ sspi->base + SIRFSOC_SPI_INT_STATUS);
+ writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
+ SIRFSOC_SPI_MUL_DAT_MODE | SIRFSOC_SPI_ENA_AUTO_CLR,
+ sspi->base + SIRFSOC_SPI_CTRL);
+ writel(min(sspi->left_tx_word, (u32)(256 / sspi->word_width))
+ - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+ writel(min(sspi->left_rx_word, (u32)(256 / sspi->word_width))
+ - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+ while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS)
+ & SIRFSOC_SPI_FIFO_FULL)) && sspi->left_tx_word)
+ sspi->tx_word(sspi);
+ writel(SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN |
+ SIRFSOC_SPI_TX_UFLOW_INT_EN |
+ SIRFSOC_SPI_RX_OFLOW_INT_EN |
+ SIRFSOC_SPI_RX_IO_DMA_INT_EN,
+ sspi->base + SIRFSOC_SPI_INT_EN);
+ writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN,
+ sspi->base + SIRFSOC_SPI_TX_RX_EN);
+ if (!wait_for_completion_timeout(&sspi->tx_done, timeout) ||
+ !wait_for_completion_timeout(&sspi->rx_done, timeout)) {
+ dev_err(&spi->dev, "transfer timeout\n");
+ break;
+ }
+ while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
+ & SIRFSOC_SPI_FIFO_EMPTY)) && sspi->left_rx_word)
+ sspi->rx_word(sspi);
+ writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ } while (sspi->left_tx_word != 0 || sspi->left_rx_word != 0);
+}
+
+static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
+{
+ struct sirfsoc_spi *sspi;
+ sspi = spi_master_get_devdata(spi->master);
+
+ sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage;
+ sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage;
+ sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width;
+ reinit_completion(&sspi->rx_done);
+ reinit_completion(&sspi->tx_done);
+ /*
+ * in the transfer, if transfer data using command register with rx_buf
+ * null, just fill command data into command register and wait for its
+ * completion.
+ */
+ if (sspi->tx_by_cmd)
+ spi_sirfsoc_cmd_transfer(spi, t);
+ else if (IS_DMA_VALID(t))
+ spi_sirfsoc_dma_transfer(spi, t);
+ else
+ spi_sirfsoc_pio_transfer(spi, t);
+
+ return t->len - sspi->left_rx_word * sspi->word_width;
+}
+
+static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
+{
+ struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
+
+ if (sspi->hw_cs) {
+ u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
+ switch (value) {
+ case BITBANG_CS_ACTIVE:
+ if (spi->mode & SPI_CS_HIGH)
+ regval |= SIRFSOC_SPI_CS_IO_OUT;
+ else
+ regval &= ~SIRFSOC_SPI_CS_IO_OUT;
+ break;
+ case BITBANG_CS_INACTIVE:
+ if (spi->mode & SPI_CS_HIGH)
+ regval &= ~SIRFSOC_SPI_CS_IO_OUT;
+ else
+ regval |= SIRFSOC_SPI_CS_IO_OUT;
+ break;
+ }
+ writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
+ } else {
+ switch (value) {
+ case BITBANG_CS_ACTIVE:
+ gpio_direction_output(spi->cs_gpio,
+ spi->mode & SPI_CS_HIGH ? 1 : 0);
+ break;
+ case BITBANG_CS_INACTIVE:
+ gpio_direction_output(spi->cs_gpio,
+ spi->mode & SPI_CS_HIGH ? 0 : 1);
+ break;
+ }
+ }
+}
+
+static int
+spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
+{
+ struct sirfsoc_spi *sspi;
+ u8 bits_per_word = 0;
+ int hz = 0;
+ u32 regval;
+ u32 txfifo_ctrl, rxfifo_ctrl;
+ u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;
+
+ sspi = spi_master_get_devdata(spi->master);
+
+ bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word;
+ hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
+
+ regval = (sspi->ctrl_freq / (2 * hz)) - 1;
+ if (regval > 0xFFFF || regval < 0) {
+ dev_err(&spi->dev, "Speed %d not supported\n", hz);
+ return -EINVAL;
+ }
+
+ switch (bits_per_word) {
+ case 8:
+ regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
+ sspi->rx_word = spi_sirfsoc_rx_word_u8;
+ sspi->tx_word = spi_sirfsoc_tx_word_u8;
+ break;
+ case 12:
+ case 16:
+ regval |= (bits_per_word == 12) ?
+ SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
+ SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
+ sspi->rx_word = spi_sirfsoc_rx_word_u16;
+ sspi->tx_word = spi_sirfsoc_tx_word_u16;
+ break;
+ case 32:
+ regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
+ sspi->rx_word = spi_sirfsoc_rx_word_u32;
+ sspi->tx_word = spi_sirfsoc_tx_word_u32;
+ break;
+ default:
+ BUG();
+ }
+
+ sspi->word_width = DIV_ROUND_UP(bits_per_word, 8);
+ txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
+ (sspi->word_width >> 1);
+ rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
+ (sspi->word_width >> 1);
+
+ if (!(spi->mode & SPI_CS_HIGH))
+ regval |= SIRFSOC_SPI_CS_IDLE_STAT;
+ if (!(spi->mode & SPI_LSB_FIRST))
+ regval |= SIRFSOC_SPI_TRAN_MSB;
+ if (spi->mode & SPI_CPOL)
+ regval |= SIRFSOC_SPI_CLK_IDLE_STAT;
+
+ /*
+ * Data should be driven at least 1/2 cycle before the fetch edge
+ * to make sure that data gets stable at the fetch edge.
+ */
+ if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
+ (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
+ regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
+ else
+ regval |= SIRFSOC_SPI_DRV_POS_EDGE;
+
+ writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) |
+ SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
+ SIRFSOC_SPI_FIFO_HC(2),
+ sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
+ writel(SIRFSOC_SPI_FIFO_SC(2) |
+ SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
+ SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
+ sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
+ writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
+ writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);
+
+ if (t && t->tx_buf && !t->rx_buf && (t->len <= SIRFSOC_MAX_CMD_BYTES)) {
+ regval |= (SIRFSOC_SPI_CMD_BYTE_NUM((t->len - 1)) |
+ SIRFSOC_SPI_CMD_MODE);
+ sspi->tx_by_cmd = true;
+ } else {
+ regval &= ~SIRFSOC_SPI_CMD_MODE;
+ sspi->tx_by_cmd = false;
+ }
+ /*
+ * it should never set to hardware cs mode because in hardware cs mode,
+ * cs signal can't controlled by driver.
+ */
+ regval |= SIRFSOC_SPI_CS_IO_MODE;
+ writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
+
+ if (IS_DMA_VALID(t)) {
+ /* Enable DMA mode for RX, TX */
+ writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
+ writel(SIRFSOC_SPI_RX_DMA_FLUSH,
+ sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
+ } else {
+ /* Enable IO mode for RX, TX */
+ writel(SIRFSOC_SPI_IO_MODE_SEL,
+ sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
+ writel(SIRFSOC_SPI_IO_MODE_SEL,
+ sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
+ }
+
+ return 0;
+}
+
+static int spi_sirfsoc_setup(struct spi_device *spi)
+{
+ struct sirfsoc_spi *sspi;
+
+ sspi = spi_master_get_devdata(spi->master);
+
+ if (spi->cs_gpio == -ENOENT)
+ sspi->hw_cs = true;
+ else
+ sspi->hw_cs = false;
+ return spi_sirfsoc_setup_transfer(spi, NULL);
+}
+
+static int spi_sirfsoc_probe(struct platform_device *pdev)
+{
+ struct sirfsoc_spi *sspi;
+ struct spi_master *master;
+ struct resource *mem_res;
+ int irq;
+ int i, ret;
+
+ ret = device_reset(&pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "SPI reset failed!\n");
+ return ret;
+ }
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*sspi));
+ if (!master) {
+ dev_err(&pdev->dev, "Unable to allocate SPI master\n");
+ return -ENOMEM;
+ }
+ platform_set_drvdata(pdev, master);
+ sspi = spi_master_get_devdata(master);
+
+ mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sspi->base = devm_ioremap_resource(&pdev->dev, mem_res);
+ if (IS_ERR(sspi->base)) {
+ ret = PTR_ERR(sspi->base);
+ goto free_master;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = -ENXIO;
+ goto free_master;
+ }
+ ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
+ DRIVER_NAME, sspi);
+ if (ret)
+ goto free_master;
+
+ sspi->bitbang.master = master;
+ sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
+ sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
+ sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
+ sspi->bitbang.master->setup = spi_sirfsoc_setup;
+ master->bus_num = pdev->id;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH;
+ master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(12) |
+ SPI_BPW_MASK(16) | SPI_BPW_MASK(32);
+ master->max_speed_hz = SIRFSOC_SPI_DEFAULT_FRQ;
+ sspi->bitbang.master->dev.of_node = pdev->dev.of_node;
+
+ /* request DMA channels */
+ sspi->rx_chan = dma_request_slave_channel(&pdev->dev, "rx");
+ if (!sspi->rx_chan) {
+ dev_err(&pdev->dev, "can not allocate rx dma channel\n");
+ ret = -ENODEV;
+ goto free_master;
+ }
+ sspi->tx_chan = dma_request_slave_channel(&pdev->dev, "tx");
+ if (!sspi->tx_chan) {
+ dev_err(&pdev->dev, "can not allocate tx dma channel\n");
+ ret = -ENODEV;
+ goto free_rx_dma;
+ }
+
+ sspi->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(sspi->clk)) {
+ ret = PTR_ERR(sspi->clk);
+ goto free_tx_dma;
+ }
+ clk_prepare_enable(sspi->clk);
+ sspi->ctrl_freq = clk_get_rate(sspi->clk);
+
+ init_completion(&sspi->rx_done);
+ init_completion(&sspi->tx_done);
+
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ /* We are not using dummy delay between command and data */
+ writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);
+
+ sspi->dummypage = kmalloc(2 * PAGE_SIZE, GFP_KERNEL);
+ if (!sspi->dummypage) {
+ ret = -ENOMEM;
+ goto free_clk;
+ }
+
+ ret = spi_bitbang_start(&sspi->bitbang);
+ if (ret)
+ goto free_dummypage;
+ for (i = 0; master->cs_gpios && i < master->num_chipselect; i++) {
+ if (master->cs_gpios[i] == -ENOENT)
+ continue;
+ if (!gpio_is_valid(master->cs_gpios[i])) {
+ dev_err(&pdev->dev, "no valid gpio\n");
+ ret = -EINVAL;
+ goto free_dummypage;
+ }
+ ret = devm_gpio_request(&pdev->dev,
+ master->cs_gpios[i], DRIVER_NAME);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request gpio\n");
+ goto free_dummypage;
+ }
+ }
+ dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);
+
+ return 0;
+free_dummypage:
+ kfree(sspi->dummypage);
+free_clk:
+ clk_disable_unprepare(sspi->clk);
+ clk_put(sspi->clk);
+free_tx_dma:
+ dma_release_channel(sspi->tx_chan);
+free_rx_dma:
+ dma_release_channel(sspi->rx_chan);
+free_master:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int spi_sirfsoc_remove(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct sirfsoc_spi *sspi;
+
+ master = platform_get_drvdata(pdev);
+ sspi = spi_master_get_devdata(master);
+
+ spi_bitbang_stop(&sspi->bitbang);
+ kfree(sspi->dummypage);
+ clk_disable_unprepare(sspi->clk);
+ clk_put(sspi->clk);
+ dma_release_channel(sspi->rx_chan);
+ dma_release_channel(sspi->tx_chan);
+ spi_master_put(master);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int spi_sirfsoc_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = spi_master_suspend(master);
+ if (ret)
+ return ret;
+
+ clk_disable(sspi->clk);
+ return 0;
+}
+
+static int spi_sirfsoc_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
+
+ clk_enable(sspi->clk);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+ writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+
+ return spi_master_resume(master);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(spi_sirfsoc_pm_ops, spi_sirfsoc_suspend,
+ spi_sirfsoc_resume);
+
+static const struct of_device_id spi_sirfsoc_of_match[] = {
+ { .compatible = "sirf,prima2-spi", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, spi_sirfsoc_of_match);
+
+static struct platform_driver spi_sirfsoc_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .pm = &spi_sirfsoc_pm_ops,
+ .of_match_table = spi_sirfsoc_of_match,
+ },
+ .probe = spi_sirfsoc_probe,
+ .remove = spi_sirfsoc_remove,
+};
+module_platform_driver(spi_sirfsoc_driver);
+MODULE_DESCRIPTION("SiRF SoC SPI master driver");
+MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>");
+MODULE_AUTHOR("Barry Song <Baohua.Song@csr.com>");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff