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path: root/drivers/spi/spi-img-spfi.c
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Diffstat (limited to 'drivers/spi/spi-img-spfi.c')
-rw-r--r--drivers/spi/spi-img-spfi.c768
1 files changed, 768 insertions, 0 deletions
diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c
new file mode 100644
index 000000000..bfd12247f
--- /dev/null
+++ b/drivers/spi/spi-img-spfi.c
@@ -0,0 +1,768 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * IMG SPFI controller driver
+ *
+ * Copyright (C) 2007,2008,2013 Imagination Technologies Ltd.
+ * Copyright (C) 2014 Google, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+
+#define SPFI_DEVICE_PARAMETER(x) (0x00 + 0x4 * (x))
+#define SPFI_DEVICE_PARAMETER_BITCLK_SHIFT 24
+#define SPFI_DEVICE_PARAMETER_BITCLK_MASK 0xff
+#define SPFI_DEVICE_PARAMETER_CSSETUP_SHIFT 16
+#define SPFI_DEVICE_PARAMETER_CSSETUP_MASK 0xff
+#define SPFI_DEVICE_PARAMETER_CSHOLD_SHIFT 8
+#define SPFI_DEVICE_PARAMETER_CSHOLD_MASK 0xff
+#define SPFI_DEVICE_PARAMETER_CSDELAY_SHIFT 0
+#define SPFI_DEVICE_PARAMETER_CSDELAY_MASK 0xff
+
+#define SPFI_CONTROL 0x14
+#define SPFI_CONTROL_CONTINUE BIT(12)
+#define SPFI_CONTROL_SOFT_RESET BIT(11)
+#define SPFI_CONTROL_SEND_DMA BIT(10)
+#define SPFI_CONTROL_GET_DMA BIT(9)
+#define SPFI_CONTROL_SE BIT(8)
+#define SPFI_CONTROL_TMODE_SHIFT 5
+#define SPFI_CONTROL_TMODE_MASK 0x7
+#define SPFI_CONTROL_TMODE_SINGLE 0
+#define SPFI_CONTROL_TMODE_DUAL 1
+#define SPFI_CONTROL_TMODE_QUAD 2
+#define SPFI_CONTROL_SPFI_EN BIT(0)
+
+#define SPFI_TRANSACTION 0x18
+#define SPFI_TRANSACTION_TSIZE_SHIFT 16
+#define SPFI_TRANSACTION_TSIZE_MASK 0xffff
+
+#define SPFI_PORT_STATE 0x1c
+#define SPFI_PORT_STATE_DEV_SEL_SHIFT 20
+#define SPFI_PORT_STATE_DEV_SEL_MASK 0x7
+#define SPFI_PORT_STATE_CK_POL(x) BIT(19 - (x))
+#define SPFI_PORT_STATE_CK_PHASE(x) BIT(14 - (x))
+
+#define SPFI_TX_32BIT_VALID_DATA 0x20
+#define SPFI_TX_8BIT_VALID_DATA 0x24
+#define SPFI_RX_32BIT_VALID_DATA 0x28
+#define SPFI_RX_8BIT_VALID_DATA 0x2c
+
+#define SPFI_INTERRUPT_STATUS 0x30
+#define SPFI_INTERRUPT_ENABLE 0x34
+#define SPFI_INTERRUPT_CLEAR 0x38
+#define SPFI_INTERRUPT_IACCESS BIT(12)
+#define SPFI_INTERRUPT_GDEX8BIT BIT(11)
+#define SPFI_INTERRUPT_ALLDONETRIG BIT(9)
+#define SPFI_INTERRUPT_GDFUL BIT(8)
+#define SPFI_INTERRUPT_GDHF BIT(7)
+#define SPFI_INTERRUPT_GDEX32BIT BIT(6)
+#define SPFI_INTERRUPT_GDTRIG BIT(5)
+#define SPFI_INTERRUPT_SDFUL BIT(3)
+#define SPFI_INTERRUPT_SDHF BIT(2)
+#define SPFI_INTERRUPT_SDE BIT(1)
+#define SPFI_INTERRUPT_SDTRIG BIT(0)
+
+/*
+ * There are four parallel FIFOs of 16 bytes each. The word buffer
+ * (*_32BIT_VALID_DATA) accesses all four FIFOs at once, resulting in an
+ * effective FIFO size of 64 bytes. The byte buffer (*_8BIT_VALID_DATA)
+ * accesses only a single FIFO, resulting in an effective FIFO size of
+ * 16 bytes.
+ */
+#define SPFI_32BIT_FIFO_SIZE 64
+#define SPFI_8BIT_FIFO_SIZE 16
+
+struct img_spfi {
+ struct device *dev;
+ struct spi_master *master;
+ spinlock_t lock;
+
+ void __iomem *regs;
+ phys_addr_t phys;
+ int irq;
+ struct clk *spfi_clk;
+ struct clk *sys_clk;
+
+ struct dma_chan *rx_ch;
+ struct dma_chan *tx_ch;
+ bool tx_dma_busy;
+ bool rx_dma_busy;
+};
+
+static inline u32 spfi_readl(struct img_spfi *spfi, u32 reg)
+{
+ return readl(spfi->regs + reg);
+}
+
+static inline void spfi_writel(struct img_spfi *spfi, u32 val, u32 reg)
+{
+ writel(val, spfi->regs + reg);
+}
+
+static inline void spfi_start(struct img_spfi *spfi)
+{
+ u32 val;
+
+ val = spfi_readl(spfi, SPFI_CONTROL);
+ val |= SPFI_CONTROL_SPFI_EN;
+ spfi_writel(spfi, val, SPFI_CONTROL);
+}
+
+static inline void spfi_reset(struct img_spfi *spfi)
+{
+ spfi_writel(spfi, SPFI_CONTROL_SOFT_RESET, SPFI_CONTROL);
+ spfi_writel(spfi, 0, SPFI_CONTROL);
+}
+
+static int spfi_wait_all_done(struct img_spfi *spfi)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(50);
+
+ while (time_before(jiffies, timeout)) {
+ u32 status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+
+ if (status & SPFI_INTERRUPT_ALLDONETRIG) {
+ spfi_writel(spfi, SPFI_INTERRUPT_ALLDONETRIG,
+ SPFI_INTERRUPT_CLEAR);
+ return 0;
+ }
+ cpu_relax();
+ }
+
+ dev_err(spfi->dev, "Timed out waiting for transaction to complete\n");
+ spfi_reset(spfi);
+
+ return -ETIMEDOUT;
+}
+
+static unsigned int spfi_pio_write32(struct img_spfi *spfi, const u32 *buf,
+ unsigned int max)
+{
+ unsigned int count = 0;
+ u32 status;
+
+ while (count < max / 4) {
+ spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR);
+ status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+ if (status & SPFI_INTERRUPT_SDFUL)
+ break;
+ spfi_writel(spfi, buf[count], SPFI_TX_32BIT_VALID_DATA);
+ count++;
+ }
+
+ return count * 4;
+}
+
+static unsigned int spfi_pio_write8(struct img_spfi *spfi, const u8 *buf,
+ unsigned int max)
+{
+ unsigned int count = 0;
+ u32 status;
+
+ while (count < max) {
+ spfi_writel(spfi, SPFI_INTERRUPT_SDFUL, SPFI_INTERRUPT_CLEAR);
+ status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+ if (status & SPFI_INTERRUPT_SDFUL)
+ break;
+ spfi_writel(spfi, buf[count], SPFI_TX_8BIT_VALID_DATA);
+ count++;
+ }
+
+ return count;
+}
+
+static unsigned int spfi_pio_read32(struct img_spfi *spfi, u32 *buf,
+ unsigned int max)
+{
+ unsigned int count = 0;
+ u32 status;
+
+ while (count < max / 4) {
+ spfi_writel(spfi, SPFI_INTERRUPT_GDEX32BIT,
+ SPFI_INTERRUPT_CLEAR);
+ status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+ if (!(status & SPFI_INTERRUPT_GDEX32BIT))
+ break;
+ buf[count] = spfi_readl(spfi, SPFI_RX_32BIT_VALID_DATA);
+ count++;
+ }
+
+ return count * 4;
+}
+
+static unsigned int spfi_pio_read8(struct img_spfi *spfi, u8 *buf,
+ unsigned int max)
+{
+ unsigned int count = 0;
+ u32 status;
+
+ while (count < max) {
+ spfi_writel(spfi, SPFI_INTERRUPT_GDEX8BIT,
+ SPFI_INTERRUPT_CLEAR);
+ status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+ if (!(status & SPFI_INTERRUPT_GDEX8BIT))
+ break;
+ buf[count] = spfi_readl(spfi, SPFI_RX_8BIT_VALID_DATA);
+ count++;
+ }
+
+ return count;
+}
+
+static int img_spfi_start_pio(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(spi->master);
+ unsigned int tx_bytes = 0, rx_bytes = 0;
+ const void *tx_buf = xfer->tx_buf;
+ void *rx_buf = xfer->rx_buf;
+ unsigned long timeout;
+ int ret;
+
+ if (tx_buf)
+ tx_bytes = xfer->len;
+ if (rx_buf)
+ rx_bytes = xfer->len;
+
+ spfi_start(spfi);
+
+ timeout = jiffies +
+ msecs_to_jiffies(xfer->len * 8 * 1000 / xfer->speed_hz + 100);
+ while ((tx_bytes > 0 || rx_bytes > 0) &&
+ time_before(jiffies, timeout)) {
+ unsigned int tx_count, rx_count;
+
+ if (tx_bytes >= 4)
+ tx_count = spfi_pio_write32(spfi, tx_buf, tx_bytes);
+ else
+ tx_count = spfi_pio_write8(spfi, tx_buf, tx_bytes);
+
+ if (rx_bytes >= 4)
+ rx_count = spfi_pio_read32(spfi, rx_buf, rx_bytes);
+ else
+ rx_count = spfi_pio_read8(spfi, rx_buf, rx_bytes);
+
+ tx_buf += tx_count;
+ rx_buf += rx_count;
+ tx_bytes -= tx_count;
+ rx_bytes -= rx_count;
+
+ cpu_relax();
+ }
+
+ if (rx_bytes > 0 || tx_bytes > 0) {
+ dev_err(spfi->dev, "PIO transfer timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ ret = spfi_wait_all_done(spfi);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static void img_spfi_dma_rx_cb(void *data)
+{
+ struct img_spfi *spfi = data;
+ unsigned long flags;
+
+ spfi_wait_all_done(spfi);
+
+ spin_lock_irqsave(&spfi->lock, flags);
+ spfi->rx_dma_busy = false;
+ if (!spfi->tx_dma_busy)
+ spi_finalize_current_transfer(spfi->master);
+ spin_unlock_irqrestore(&spfi->lock, flags);
+}
+
+static void img_spfi_dma_tx_cb(void *data)
+{
+ struct img_spfi *spfi = data;
+ unsigned long flags;
+
+ spfi_wait_all_done(spfi);
+
+ spin_lock_irqsave(&spfi->lock, flags);
+ spfi->tx_dma_busy = false;
+ if (!spfi->rx_dma_busy)
+ spi_finalize_current_transfer(spfi->master);
+ spin_unlock_irqrestore(&spfi->lock, flags);
+}
+
+static int img_spfi_start_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(spi->master);
+ struct dma_async_tx_descriptor *rxdesc = NULL, *txdesc = NULL;
+ struct dma_slave_config rxconf, txconf;
+
+ spfi->rx_dma_busy = false;
+ spfi->tx_dma_busy = false;
+
+ if (xfer->rx_buf) {
+ rxconf.direction = DMA_DEV_TO_MEM;
+ if (xfer->len % 4 == 0) {
+ rxconf.src_addr = spfi->phys + SPFI_RX_32BIT_VALID_DATA;
+ rxconf.src_addr_width = 4;
+ rxconf.src_maxburst = 4;
+ } else {
+ rxconf.src_addr = spfi->phys + SPFI_RX_8BIT_VALID_DATA;
+ rxconf.src_addr_width = 1;
+ rxconf.src_maxburst = 4;
+ }
+ dmaengine_slave_config(spfi->rx_ch, &rxconf);
+
+ rxdesc = dmaengine_prep_slave_sg(spfi->rx_ch, xfer->rx_sg.sgl,
+ xfer->rx_sg.nents,
+ DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT);
+ if (!rxdesc)
+ goto stop_dma;
+
+ rxdesc->callback = img_spfi_dma_rx_cb;
+ rxdesc->callback_param = spfi;
+ }
+
+ if (xfer->tx_buf) {
+ txconf.direction = DMA_MEM_TO_DEV;
+ if (xfer->len % 4 == 0) {
+ txconf.dst_addr = spfi->phys + SPFI_TX_32BIT_VALID_DATA;
+ txconf.dst_addr_width = 4;
+ txconf.dst_maxburst = 4;
+ } else {
+ txconf.dst_addr = spfi->phys + SPFI_TX_8BIT_VALID_DATA;
+ txconf.dst_addr_width = 1;
+ txconf.dst_maxburst = 4;
+ }
+ dmaengine_slave_config(spfi->tx_ch, &txconf);
+
+ txdesc = dmaengine_prep_slave_sg(spfi->tx_ch, xfer->tx_sg.sgl,
+ xfer->tx_sg.nents,
+ DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT);
+ if (!txdesc)
+ goto stop_dma;
+
+ txdesc->callback = img_spfi_dma_tx_cb;
+ txdesc->callback_param = spfi;
+ }
+
+ if (xfer->rx_buf) {
+ spfi->rx_dma_busy = true;
+ dmaengine_submit(rxdesc);
+ dma_async_issue_pending(spfi->rx_ch);
+ }
+
+ spfi_start(spfi);
+
+ if (xfer->tx_buf) {
+ spfi->tx_dma_busy = true;
+ dmaengine_submit(txdesc);
+ dma_async_issue_pending(spfi->tx_ch);
+ }
+
+ return 1;
+
+stop_dma:
+ dmaengine_terminate_all(spfi->rx_ch);
+ dmaengine_terminate_all(spfi->tx_ch);
+ return -EIO;
+}
+
+static void img_spfi_handle_err(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+ unsigned long flags;
+
+ /*
+ * Stop all DMA and reset the controller if the previous transaction
+ * timed-out and never completed it's DMA.
+ */
+ spin_lock_irqsave(&spfi->lock, flags);
+ if (spfi->tx_dma_busy || spfi->rx_dma_busy) {
+ spfi->tx_dma_busy = false;
+ spfi->rx_dma_busy = false;
+
+ dmaengine_terminate_all(spfi->tx_ch);
+ dmaengine_terminate_all(spfi->rx_ch);
+ }
+ spin_unlock_irqrestore(&spfi->lock, flags);
+}
+
+static int img_spfi_prepare(struct spi_master *master, struct spi_message *msg)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+ u32 val;
+
+ val = spfi_readl(spfi, SPFI_PORT_STATE);
+ val &= ~(SPFI_PORT_STATE_DEV_SEL_MASK <<
+ SPFI_PORT_STATE_DEV_SEL_SHIFT);
+ val |= msg->spi->chip_select << SPFI_PORT_STATE_DEV_SEL_SHIFT;
+ if (msg->spi->mode & SPI_CPHA)
+ val |= SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
+ else
+ val &= ~SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
+ if (msg->spi->mode & SPI_CPOL)
+ val |= SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
+ else
+ val &= ~SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
+ spfi_writel(spfi, val, SPFI_PORT_STATE);
+
+ return 0;
+}
+
+static int img_spfi_unprepare(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+
+ spfi_reset(spfi);
+
+ return 0;
+}
+
+static void img_spfi_config(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(spi->master);
+ u32 val, div;
+
+ /*
+ * output = spfi_clk * (BITCLK / 512), where BITCLK must be a
+ * power of 2 up to 128
+ */
+ div = DIV_ROUND_UP(clk_get_rate(spfi->spfi_clk), xfer->speed_hz);
+ div = clamp(512 / (1 << get_count_order(div)), 1, 128);
+
+ val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(spi->chip_select));
+ val &= ~(SPFI_DEVICE_PARAMETER_BITCLK_MASK <<
+ SPFI_DEVICE_PARAMETER_BITCLK_SHIFT);
+ val |= div << SPFI_DEVICE_PARAMETER_BITCLK_SHIFT;
+ spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(spi->chip_select));
+
+ spfi_writel(spfi, xfer->len << SPFI_TRANSACTION_TSIZE_SHIFT,
+ SPFI_TRANSACTION);
+
+ val = spfi_readl(spfi, SPFI_CONTROL);
+ val &= ~(SPFI_CONTROL_SEND_DMA | SPFI_CONTROL_GET_DMA);
+ if (xfer->tx_buf)
+ val |= SPFI_CONTROL_SEND_DMA;
+ if (xfer->rx_buf)
+ val |= SPFI_CONTROL_GET_DMA;
+ val &= ~(SPFI_CONTROL_TMODE_MASK << SPFI_CONTROL_TMODE_SHIFT);
+ if (xfer->tx_nbits == SPI_NBITS_DUAL &&
+ xfer->rx_nbits == SPI_NBITS_DUAL)
+ val |= SPFI_CONTROL_TMODE_DUAL << SPFI_CONTROL_TMODE_SHIFT;
+ else if (xfer->tx_nbits == SPI_NBITS_QUAD &&
+ xfer->rx_nbits == SPI_NBITS_QUAD)
+ val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT;
+ val |= SPFI_CONTROL_SE;
+ spfi_writel(spfi, val, SPFI_CONTROL);
+}
+
+static int img_spfi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct img_spfi *spfi = spi_master_get_devdata(spi->master);
+ int ret;
+
+ if (xfer->len > SPFI_TRANSACTION_TSIZE_MASK) {
+ dev_err(spfi->dev,
+ "Transfer length (%d) is greater than the max supported (%d)",
+ xfer->len, SPFI_TRANSACTION_TSIZE_MASK);
+ return -EINVAL;
+ }
+
+ img_spfi_config(master, spi, xfer);
+ if (master->can_dma && master->can_dma(master, spi, xfer))
+ ret = img_spfi_start_dma(master, spi, xfer);
+ else
+ ret = img_spfi_start_pio(master, spi, xfer);
+
+ return ret;
+}
+
+static bool img_spfi_can_dma(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ if (xfer->len > SPFI_32BIT_FIFO_SIZE)
+ return true;
+ return false;
+}
+
+static irqreturn_t img_spfi_irq(int irq, void *dev_id)
+{
+ struct img_spfi *spfi = (struct img_spfi *)dev_id;
+ u32 status;
+
+ status = spfi_readl(spfi, SPFI_INTERRUPT_STATUS);
+ if (status & SPFI_INTERRUPT_IACCESS) {
+ spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_CLEAR);
+ dev_err(spfi->dev, "Illegal access interrupt");
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static int img_spfi_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct img_spfi *spfi;
+ struct resource *res;
+ int ret;
+ u32 max_speed_hz;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*spfi));
+ if (!master)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, master);
+
+ spfi = spi_master_get_devdata(master);
+ spfi->dev = &pdev->dev;
+ spfi->master = master;
+ spin_lock_init(&spfi->lock);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ spfi->regs = devm_ioremap_resource(spfi->dev, res);
+ if (IS_ERR(spfi->regs)) {
+ ret = PTR_ERR(spfi->regs);
+ goto put_spi;
+ }
+ spfi->phys = res->start;
+
+ spfi->irq = platform_get_irq(pdev, 0);
+ if (spfi->irq < 0) {
+ ret = spfi->irq;
+ goto put_spi;
+ }
+ ret = devm_request_irq(spfi->dev, spfi->irq, img_spfi_irq,
+ IRQ_TYPE_LEVEL_HIGH, dev_name(spfi->dev), spfi);
+ if (ret)
+ goto put_spi;
+
+ spfi->sys_clk = devm_clk_get(spfi->dev, "sys");
+ if (IS_ERR(spfi->sys_clk)) {
+ ret = PTR_ERR(spfi->sys_clk);
+ goto put_spi;
+ }
+ spfi->spfi_clk = devm_clk_get(spfi->dev, "spfi");
+ if (IS_ERR(spfi->spfi_clk)) {
+ ret = PTR_ERR(spfi->spfi_clk);
+ goto put_spi;
+ }
+
+ ret = clk_prepare_enable(spfi->sys_clk);
+ if (ret)
+ goto put_spi;
+ ret = clk_prepare_enable(spfi->spfi_clk);
+ if (ret)
+ goto disable_pclk;
+
+ spfi_reset(spfi);
+ /*
+ * Only enable the error (IACCESS) interrupt. In PIO mode we'll
+ * poll the status of the FIFOs.
+ */
+ spfi_writel(spfi, SPFI_INTERRUPT_IACCESS, SPFI_INTERRUPT_ENABLE);
+
+ master->auto_runtime_pm = true;
+ master->bus_num = pdev->id;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_DUAL | SPI_RX_DUAL;
+ if (of_property_read_bool(spfi->dev->of_node, "img,supports-quad-mode"))
+ master->mode_bits |= SPI_TX_QUAD | SPI_RX_QUAD;
+ master->dev.of_node = pdev->dev.of_node;
+ master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(8);
+ master->max_speed_hz = clk_get_rate(spfi->spfi_clk) / 4;
+ master->min_speed_hz = clk_get_rate(spfi->spfi_clk) / 512;
+
+ /*
+ * Maximum speed supported by spfi is limited to the lower value
+ * between 1/4 of the SPFI clock or to "spfi-max-frequency"
+ * defined in the device tree.
+ * If no value is defined in the device tree assume the maximum
+ * speed supported to be 1/4 of the SPFI clock.
+ */
+ if (!of_property_read_u32(spfi->dev->of_node, "spfi-max-frequency",
+ &max_speed_hz)) {
+ if (master->max_speed_hz > max_speed_hz)
+ master->max_speed_hz = max_speed_hz;
+ }
+
+ master->transfer_one = img_spfi_transfer_one;
+ master->prepare_message = img_spfi_prepare;
+ master->unprepare_message = img_spfi_unprepare;
+ master->handle_err = img_spfi_handle_err;
+ master->use_gpio_descriptors = true;
+
+ spfi->tx_ch = dma_request_chan(spfi->dev, "tx");
+ if (IS_ERR(spfi->tx_ch)) {
+ ret = PTR_ERR(spfi->tx_ch);
+ spfi->tx_ch = NULL;
+ if (ret == -EPROBE_DEFER)
+ goto disable_pm;
+ }
+
+ spfi->rx_ch = dma_request_chan(spfi->dev, "rx");
+ if (IS_ERR(spfi->rx_ch)) {
+ ret = PTR_ERR(spfi->rx_ch);
+ spfi->rx_ch = NULL;
+ if (ret == -EPROBE_DEFER)
+ goto disable_pm;
+ }
+
+ if (!spfi->tx_ch || !spfi->rx_ch) {
+ if (spfi->tx_ch)
+ dma_release_channel(spfi->tx_ch);
+ if (spfi->rx_ch)
+ dma_release_channel(spfi->rx_ch);
+ spfi->tx_ch = NULL;
+ spfi->rx_ch = NULL;
+ dev_warn(spfi->dev, "Failed to get DMA channels, falling back to PIO mode\n");
+ } else {
+ master->dma_tx = spfi->tx_ch;
+ master->dma_rx = spfi->rx_ch;
+ master->can_dma = img_spfi_can_dma;
+ }
+
+ pm_runtime_set_active(spfi->dev);
+ pm_runtime_enable(spfi->dev);
+
+ ret = devm_spi_register_master(spfi->dev, master);
+ if (ret)
+ goto disable_pm;
+
+ return 0;
+
+disable_pm:
+ pm_runtime_disable(spfi->dev);
+ if (spfi->rx_ch)
+ dma_release_channel(spfi->rx_ch);
+ if (spfi->tx_ch)
+ dma_release_channel(spfi->tx_ch);
+ clk_disable_unprepare(spfi->spfi_clk);
+disable_pclk:
+ clk_disable_unprepare(spfi->sys_clk);
+put_spi:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int img_spfi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+
+ if (spfi->tx_ch)
+ dma_release_channel(spfi->tx_ch);
+ if (spfi->rx_ch)
+ dma_release_channel(spfi->rx_ch);
+
+ pm_runtime_disable(spfi->dev);
+ if (!pm_runtime_status_suspended(spfi->dev)) {
+ clk_disable_unprepare(spfi->spfi_clk);
+ clk_disable_unprepare(spfi->sys_clk);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int img_spfi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+
+ clk_disable_unprepare(spfi->spfi_clk);
+ clk_disable_unprepare(spfi->sys_clk);
+
+ return 0;
+}
+
+static int img_spfi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = clk_prepare_enable(spfi->sys_clk);
+ if (ret)
+ return ret;
+ ret = clk_prepare_enable(spfi->spfi_clk);
+ if (ret) {
+ clk_disable_unprepare(spfi->sys_clk);
+ return ret;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+#ifdef CONFIG_PM_SLEEP
+static int img_spfi_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+
+ return spi_master_suspend(master);
+}
+
+static int img_spfi_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct img_spfi *spfi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret < 0)
+ return ret;
+ spfi_reset(spfi);
+ pm_runtime_put(dev);
+
+ return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops img_spfi_pm_ops = {
+ SET_RUNTIME_PM_OPS(img_spfi_runtime_suspend, img_spfi_runtime_resume,
+ NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(img_spfi_suspend, img_spfi_resume)
+};
+
+static const struct of_device_id img_spfi_of_match[] = {
+ { .compatible = "img,spfi", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, img_spfi_of_match);
+
+static struct platform_driver img_spfi_driver = {
+ .driver = {
+ .name = "img-spfi",
+ .pm = &img_spfi_pm_ops,
+ .of_match_table = of_match_ptr(img_spfi_of_match),
+ },
+ .probe = img_spfi_probe,
+ .remove = img_spfi_remove,
+};
+module_platform_driver(img_spfi_driver);
+
+MODULE_DESCRIPTION("IMG SPFI controller driver");
+MODULE_AUTHOR("Andrew Bresticker <abrestic@chromium.org>");
+MODULE_LICENSE("GPL v2");