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-rw-r--r--drivers/spi/spi-omap2-mcspi.c1617
1 files changed, 1617 insertions, 0 deletions
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
new file mode 100644
index 000000000..6ba9b0d77
--- /dev/null
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -0,0 +1,1617 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OMAP2 McSPI controller driver
+ *
+ * Copyright (C) 2005, 2006 Nokia Corporation
+ * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
+ * Juha Yrjola <juha.yrjola@nokia.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/gcd.h>
+
+#include <linux/spi/spi.h>
+
+#include <linux/platform_data/spi-omap2-mcspi.h>
+
+#define OMAP2_MCSPI_MAX_FREQ 48000000
+#define OMAP2_MCSPI_MAX_DIVIDER 4096
+#define OMAP2_MCSPI_MAX_FIFODEPTH 64
+#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
+#define SPI_AUTOSUSPEND_TIMEOUT 2000
+
+#define OMAP2_MCSPI_REVISION 0x00
+#define OMAP2_MCSPI_SYSSTATUS 0x14
+#define OMAP2_MCSPI_IRQSTATUS 0x18
+#define OMAP2_MCSPI_IRQENABLE 0x1c
+#define OMAP2_MCSPI_WAKEUPENABLE 0x20
+#define OMAP2_MCSPI_SYST 0x24
+#define OMAP2_MCSPI_MODULCTRL 0x28
+#define OMAP2_MCSPI_XFERLEVEL 0x7c
+
+/* per-channel banks, 0x14 bytes each, first is: */
+#define OMAP2_MCSPI_CHCONF0 0x2c
+#define OMAP2_MCSPI_CHSTAT0 0x30
+#define OMAP2_MCSPI_CHCTRL0 0x34
+#define OMAP2_MCSPI_TX0 0x38
+#define OMAP2_MCSPI_RX0 0x3c
+
+/* per-register bitmasks: */
+#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
+
+#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
+#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
+#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
+
+#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
+#define OMAP2_MCSPI_CHCONF_POL BIT(1)
+#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
+#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
+#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
+#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
+#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
+#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
+#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
+#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
+#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
+#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
+#define OMAP2_MCSPI_CHCONF_IS BIT(18)
+#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
+#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
+#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
+#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
+#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
+
+#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
+#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
+#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
+#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
+
+#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
+#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
+
+#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
+
+/* We have 2 DMA channels per CS, one for RX and one for TX */
+struct omap2_mcspi_dma {
+ struct dma_chan *dma_tx;
+ struct dma_chan *dma_rx;
+
+ struct completion dma_tx_completion;
+ struct completion dma_rx_completion;
+
+ char dma_rx_ch_name[14];
+ char dma_tx_ch_name[14];
+};
+
+/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
+ * cache operations; better heuristics consider wordsize and bitrate.
+ */
+#define DMA_MIN_BYTES 160
+
+
+/*
+ * Used for context save and restore, structure members to be updated whenever
+ * corresponding registers are modified.
+ */
+struct omap2_mcspi_regs {
+ u32 modulctrl;
+ u32 wakeupenable;
+ struct list_head cs;
+};
+
+struct omap2_mcspi {
+ struct completion txdone;
+ struct spi_master *master;
+ /* Virtual base address of the controller */
+ void __iomem *base;
+ unsigned long phys;
+ /* SPI1 has 4 channels, while SPI2 has 2 */
+ struct omap2_mcspi_dma *dma_channels;
+ struct device *dev;
+ struct omap2_mcspi_regs ctx;
+ int fifo_depth;
+ bool slave_aborted;
+ unsigned int pin_dir:1;
+ size_t max_xfer_len;
+};
+
+struct omap2_mcspi_cs {
+ void __iomem *base;
+ unsigned long phys;
+ int word_len;
+ u16 mode;
+ struct list_head node;
+ /* Context save and restore shadow register */
+ u32 chconf0, chctrl0;
+};
+
+static inline void mcspi_write_reg(struct spi_master *master,
+ int idx, u32 val)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+
+ writel_relaxed(val, mcspi->base + idx);
+}
+
+static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+
+ return readl_relaxed(mcspi->base + idx);
+}
+
+static inline void mcspi_write_cs_reg(const struct spi_device *spi,
+ int idx, u32 val)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+
+ writel_relaxed(val, cs->base + idx);
+}
+
+static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+
+ return readl_relaxed(cs->base + idx);
+}
+
+static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+
+ return cs->chconf0;
+}
+
+static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+
+ cs->chconf0 = val;
+ mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
+}
+
+static inline int mcspi_bytes_per_word(int word_len)
+{
+ if (word_len <= 8)
+ return 1;
+ else if (word_len <= 16)
+ return 2;
+ else /* word_len <= 32 */
+ return 4;
+}
+
+static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
+ int is_read, int enable)
+{
+ u32 l, rw;
+
+ l = mcspi_cached_chconf0(spi);
+
+ if (is_read) /* 1 is read, 0 write */
+ rw = OMAP2_MCSPI_CHCONF_DMAR;
+ else
+ rw = OMAP2_MCSPI_CHCONF_DMAW;
+
+ if (enable)
+ l |= rw;
+ else
+ l &= ~rw;
+
+ mcspi_write_chconf0(spi, l);
+}
+
+static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ u32 l;
+
+ l = cs->chctrl0;
+ if (enable)
+ l |= OMAP2_MCSPI_CHCTRL_EN;
+ else
+ l &= ~OMAP2_MCSPI_CHCTRL_EN;
+ cs->chctrl0 = l;
+ mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
+ /* Flash post-writes */
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
+}
+
+static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ u32 l;
+
+ /* The controller handles the inverted chip selects
+ * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
+ * the inversion from the core spi_set_cs function.
+ */
+ if (spi->mode & SPI_CS_HIGH)
+ enable = !enable;
+
+ if (spi->controller_state) {
+ int err = pm_runtime_resume_and_get(mcspi->dev);
+ if (err < 0) {
+ dev_err(mcspi->dev, "failed to get sync: %d\n", err);
+ return;
+ }
+
+ l = mcspi_cached_chconf0(spi);
+
+ if (enable)
+ l &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ else
+ l |= OMAP2_MCSPI_CHCONF_FORCE;
+
+ mcspi_write_chconf0(spi, l);
+
+ pm_runtime_mark_last_busy(mcspi->dev);
+ pm_runtime_put_autosuspend(mcspi->dev);
+ }
+}
+
+static void omap2_mcspi_set_mode(struct spi_master *master)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ u32 l;
+
+ /*
+ * Choose master or slave mode
+ */
+ l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
+ l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
+ if (spi_controller_is_slave(master)) {
+ l |= (OMAP2_MCSPI_MODULCTRL_MS);
+ } else {
+ l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
+ l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
+ }
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
+
+ ctx->modulctrl = l;
+}
+
+static void omap2_mcspi_set_fifo(const struct spi_device *spi,
+ struct spi_transfer *t, int enable)
+{
+ struct spi_master *master = spi->master;
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ struct omap2_mcspi *mcspi;
+ unsigned int wcnt;
+ int max_fifo_depth, bytes_per_word;
+ u32 chconf, xferlevel;
+
+ mcspi = spi_master_get_devdata(master);
+
+ chconf = mcspi_cached_chconf0(spi);
+ if (enable) {
+ bytes_per_word = mcspi_bytes_per_word(cs->word_len);
+ if (t->len % bytes_per_word != 0)
+ goto disable_fifo;
+
+ if (t->rx_buf != NULL && t->tx_buf != NULL)
+ max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
+ else
+ max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
+
+ wcnt = t->len / bytes_per_word;
+ if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
+ goto disable_fifo;
+
+ xferlevel = wcnt << 16;
+ if (t->rx_buf != NULL) {
+ chconf |= OMAP2_MCSPI_CHCONF_FFER;
+ xferlevel |= (bytes_per_word - 1) << 8;
+ }
+
+ if (t->tx_buf != NULL) {
+ chconf |= OMAP2_MCSPI_CHCONF_FFET;
+ xferlevel |= bytes_per_word - 1;
+ }
+
+ mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
+ mcspi_write_chconf0(spi, chconf);
+ mcspi->fifo_depth = max_fifo_depth;
+
+ return;
+ }
+
+disable_fifo:
+ if (t->rx_buf != NULL)
+ chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
+
+ if (t->tx_buf != NULL)
+ chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
+
+ mcspi_write_chconf0(spi, chconf);
+ mcspi->fifo_depth = 0;
+}
+
+static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
+{
+ unsigned long timeout;
+
+ timeout = jiffies + msecs_to_jiffies(1000);
+ while (!(readl_relaxed(reg) & bit)) {
+ if (time_after(jiffies, timeout)) {
+ if (!(readl_relaxed(reg) & bit))
+ return -ETIMEDOUT;
+ else
+ return 0;
+ }
+ cpu_relax();
+ }
+ return 0;
+}
+
+static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi,
+ struct completion *x)
+{
+ if (spi_controller_is_slave(mcspi->master)) {
+ if (wait_for_completion_interruptible(x) ||
+ mcspi->slave_aborted)
+ return -EINTR;
+ } else {
+ wait_for_completion(x);
+ }
+
+ return 0;
+}
+
+static void omap2_mcspi_rx_callback(void *data)
+{
+ struct spi_device *spi = data;
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+
+ /* We must disable the DMA RX request */
+ omap2_mcspi_set_dma_req(spi, 1, 0);
+
+ complete(&mcspi_dma->dma_rx_completion);
+}
+
+static void omap2_mcspi_tx_callback(void *data)
+{
+ struct spi_device *spi = data;
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+
+ /* We must disable the DMA TX request */
+ omap2_mcspi_set_dma_req(spi, 0, 0);
+
+ complete(&mcspi_dma->dma_tx_completion);
+}
+
+static void omap2_mcspi_tx_dma(struct spi_device *spi,
+ struct spi_transfer *xfer,
+ struct dma_slave_config cfg)
+{
+ struct omap2_mcspi *mcspi;
+ struct omap2_mcspi_dma *mcspi_dma;
+ struct dma_async_tx_descriptor *tx;
+
+ mcspi = spi_master_get_devdata(spi->master);
+ mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+
+ dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
+
+ tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
+ xfer->tx_sg.nents,
+ DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (tx) {
+ tx->callback = omap2_mcspi_tx_callback;
+ tx->callback_param = spi;
+ dmaengine_submit(tx);
+ } else {
+ /* FIXME: fall back to PIO? */
+ }
+ dma_async_issue_pending(mcspi_dma->dma_tx);
+ omap2_mcspi_set_dma_req(spi, 0, 1);
+}
+
+static unsigned
+omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
+ struct dma_slave_config cfg,
+ unsigned es)
+{
+ struct omap2_mcspi *mcspi;
+ struct omap2_mcspi_dma *mcspi_dma;
+ unsigned int count, transfer_reduction = 0;
+ struct scatterlist *sg_out[2];
+ int nb_sizes = 0, out_mapped_nents[2], ret, x;
+ size_t sizes[2];
+ u32 l;
+ int elements = 0;
+ int word_len, element_count;
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
+ struct dma_async_tx_descriptor *tx;
+
+ mcspi = spi_master_get_devdata(spi->master);
+ mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+ count = xfer->len;
+
+ /*
+ * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
+ * it mentions reducing DMA transfer length by one element in master
+ * normal mode.
+ */
+ if (mcspi->fifo_depth == 0)
+ transfer_reduction = es;
+
+ word_len = cs->word_len;
+ l = mcspi_cached_chconf0(spi);
+
+ if (word_len <= 8)
+ element_count = count;
+ else if (word_len <= 16)
+ element_count = count >> 1;
+ else /* word_len <= 32 */
+ element_count = count >> 2;
+
+
+ dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
+
+ /*
+ * Reduce DMA transfer length by one more if McSPI is
+ * configured in turbo mode.
+ */
+ if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
+ transfer_reduction += es;
+
+ if (transfer_reduction) {
+ /* Split sgl into two. The second sgl won't be used. */
+ sizes[0] = count - transfer_reduction;
+ sizes[1] = transfer_reduction;
+ nb_sizes = 2;
+ } else {
+ /*
+ * Don't bother splitting the sgl. This essentially
+ * clones the original sgl.
+ */
+ sizes[0] = count;
+ nb_sizes = 1;
+ }
+
+ ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
+ sizes, sg_out, out_mapped_nents, GFP_KERNEL);
+
+ if (ret < 0) {
+ dev_err(&spi->dev, "sg_split failed\n");
+ return 0;
+ }
+
+ tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
+ out_mapped_nents[0], DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (tx) {
+ tx->callback = omap2_mcspi_rx_callback;
+ tx->callback_param = spi;
+ dmaengine_submit(tx);
+ } else {
+ /* FIXME: fall back to PIO? */
+ }
+
+ dma_async_issue_pending(mcspi_dma->dma_rx);
+ omap2_mcspi_set_dma_req(spi, 1, 1);
+
+ ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
+ if (ret || mcspi->slave_aborted) {
+ dmaengine_terminate_sync(mcspi_dma->dma_rx);
+ omap2_mcspi_set_dma_req(spi, 1, 0);
+ return 0;
+ }
+
+ for (x = 0; x < nb_sizes; x++)
+ kfree(sg_out[x]);
+
+ if (mcspi->fifo_depth > 0)
+ return count;
+
+ /*
+ * Due to the DMA transfer length reduction the missing bytes must
+ * be read manually to receive all of the expected data.
+ */
+ omap2_mcspi_set_enable(spi, 0);
+
+ elements = element_count - 1;
+
+ if (l & OMAP2_MCSPI_CHCONF_TURBO) {
+ elements--;
+
+ if (!mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS)) {
+ u32 w;
+
+ w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
+ if (word_len <= 8)
+ ((u8 *)xfer->rx_buf)[elements++] = w;
+ else if (word_len <= 16)
+ ((u16 *)xfer->rx_buf)[elements++] = w;
+ else /* word_len <= 32 */
+ ((u32 *)xfer->rx_buf)[elements++] = w;
+ } else {
+ int bytes_per_word = mcspi_bytes_per_word(word_len);
+ dev_err(&spi->dev, "DMA RX penultimate word empty\n");
+ count -= (bytes_per_word << 1);
+ omap2_mcspi_set_enable(spi, 1);
+ return count;
+ }
+ }
+ if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
+ u32 w;
+
+ w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
+ if (word_len <= 8)
+ ((u8 *)xfer->rx_buf)[elements] = w;
+ else if (word_len <= 16)
+ ((u16 *)xfer->rx_buf)[elements] = w;
+ else /* word_len <= 32 */
+ ((u32 *)xfer->rx_buf)[elements] = w;
+ } else {
+ dev_err(&spi->dev, "DMA RX last word empty\n");
+ count -= mcspi_bytes_per_word(word_len);
+ }
+ omap2_mcspi_set_enable(spi, 1);
+ return count;
+}
+
+static unsigned
+omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
+{
+ struct omap2_mcspi *mcspi;
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ struct omap2_mcspi_dma *mcspi_dma;
+ unsigned int count;
+ u8 *rx;
+ const u8 *tx;
+ struct dma_slave_config cfg;
+ enum dma_slave_buswidth width;
+ unsigned es;
+ void __iomem *chstat_reg;
+ void __iomem *irqstat_reg;
+ int wait_res;
+
+ mcspi = spi_master_get_devdata(spi->master);
+ mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+
+ if (cs->word_len <= 8) {
+ width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ es = 1;
+ } else if (cs->word_len <= 16) {
+ width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ es = 2;
+ } else {
+ width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ es = 4;
+ }
+
+ count = xfer->len;
+
+ memset(&cfg, 0, sizeof(cfg));
+ cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
+ cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
+ cfg.src_addr_width = width;
+ cfg.dst_addr_width = width;
+ cfg.src_maxburst = 1;
+ cfg.dst_maxburst = 1;
+
+ rx = xfer->rx_buf;
+ tx = xfer->tx_buf;
+
+ mcspi->slave_aborted = false;
+ reinit_completion(&mcspi_dma->dma_tx_completion);
+ reinit_completion(&mcspi_dma->dma_rx_completion);
+ reinit_completion(&mcspi->txdone);
+ if (tx) {
+ /* Enable EOW IRQ to know end of tx in slave mode */
+ if (spi_controller_is_slave(spi->master))
+ mcspi_write_reg(spi->master,
+ OMAP2_MCSPI_IRQENABLE,
+ OMAP2_MCSPI_IRQSTATUS_EOW);
+ omap2_mcspi_tx_dma(spi, xfer, cfg);
+ }
+
+ if (rx != NULL)
+ count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
+
+ if (tx != NULL) {
+ int ret;
+
+ ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
+ if (ret || mcspi->slave_aborted) {
+ dmaengine_terminate_sync(mcspi_dma->dma_tx);
+ omap2_mcspi_set_dma_req(spi, 0, 0);
+ return 0;
+ }
+
+ if (spi_controller_is_slave(mcspi->master)) {
+ ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
+ if (ret || mcspi->slave_aborted)
+ return 0;
+ }
+
+ if (mcspi->fifo_depth > 0) {
+ irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
+
+ if (mcspi_wait_for_reg_bit(irqstat_reg,
+ OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
+ dev_err(&spi->dev, "EOW timed out\n");
+
+ mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
+ OMAP2_MCSPI_IRQSTATUS_EOW);
+ }
+
+ /* for TX_ONLY mode, be sure all words have shifted out */
+ if (rx == NULL) {
+ chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
+ if (mcspi->fifo_depth > 0) {
+ wait_res = mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXFFE);
+ if (wait_res < 0)
+ dev_err(&spi->dev, "TXFFE timed out\n");
+ } else {
+ wait_res = mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXS);
+ if (wait_res < 0)
+ dev_err(&spi->dev, "TXS timed out\n");
+ }
+ if (wait_res >= 0 &&
+ (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_EOT) < 0))
+ dev_err(&spi->dev, "EOT timed out\n");
+ }
+ }
+ return count;
+}
+
+static unsigned
+omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ unsigned int count, c;
+ u32 l;
+ void __iomem *base = cs->base;
+ void __iomem *tx_reg;
+ void __iomem *rx_reg;
+ void __iomem *chstat_reg;
+ int word_len;
+
+ count = xfer->len;
+ c = count;
+ word_len = cs->word_len;
+
+ l = mcspi_cached_chconf0(spi);
+
+ /* We store the pre-calculated register addresses on stack to speed
+ * up the transfer loop. */
+ tx_reg = base + OMAP2_MCSPI_TX0;
+ rx_reg = base + OMAP2_MCSPI_RX0;
+ chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
+
+ if (c < (word_len>>3))
+ return 0;
+
+ if (word_len <= 8) {
+ u8 *rx;
+ const u8 *tx;
+
+ rx = xfer->rx_buf;
+ tx = xfer->tx_buf;
+
+ do {
+ c -= 1;
+ if (tx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXS) < 0) {
+ dev_err(&spi->dev, "TXS timed out\n");
+ goto out;
+ }
+ dev_vdbg(&spi->dev, "write-%d %02x\n",
+ word_len, *tx);
+ writel_relaxed(*tx++, tx_reg);
+ }
+ if (rx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev, "RXS timed out\n");
+ goto out;
+ }
+
+ if (c == 1 && tx == NULL &&
+ (l & OMAP2_MCSPI_CHCONF_TURBO)) {
+ omap2_mcspi_set_enable(spi, 0);
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %02x\n",
+ word_len, *(rx - 1));
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev,
+ "RXS timed out\n");
+ goto out;
+ }
+ c = 0;
+ } else if (c == 0 && tx == NULL) {
+ omap2_mcspi_set_enable(spi, 0);
+ }
+
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %02x\n",
+ word_len, *(rx - 1));
+ }
+ /* Add word delay between each word */
+ spi_delay_exec(&xfer->word_delay, xfer);
+ } while (c);
+ } else if (word_len <= 16) {
+ u16 *rx;
+ const u16 *tx;
+
+ rx = xfer->rx_buf;
+ tx = xfer->tx_buf;
+ do {
+ c -= 2;
+ if (tx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXS) < 0) {
+ dev_err(&spi->dev, "TXS timed out\n");
+ goto out;
+ }
+ dev_vdbg(&spi->dev, "write-%d %04x\n",
+ word_len, *tx);
+ writel_relaxed(*tx++, tx_reg);
+ }
+ if (rx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev, "RXS timed out\n");
+ goto out;
+ }
+
+ if (c == 2 && tx == NULL &&
+ (l & OMAP2_MCSPI_CHCONF_TURBO)) {
+ omap2_mcspi_set_enable(spi, 0);
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %04x\n",
+ word_len, *(rx - 1));
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev,
+ "RXS timed out\n");
+ goto out;
+ }
+ c = 0;
+ } else if (c == 0 && tx == NULL) {
+ omap2_mcspi_set_enable(spi, 0);
+ }
+
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %04x\n",
+ word_len, *(rx - 1));
+ }
+ /* Add word delay between each word */
+ spi_delay_exec(&xfer->word_delay, xfer);
+ } while (c >= 2);
+ } else if (word_len <= 32) {
+ u32 *rx;
+ const u32 *tx;
+
+ rx = xfer->rx_buf;
+ tx = xfer->tx_buf;
+ do {
+ c -= 4;
+ if (tx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXS) < 0) {
+ dev_err(&spi->dev, "TXS timed out\n");
+ goto out;
+ }
+ dev_vdbg(&spi->dev, "write-%d %08x\n",
+ word_len, *tx);
+ writel_relaxed(*tx++, tx_reg);
+ }
+ if (rx != NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev, "RXS timed out\n");
+ goto out;
+ }
+
+ if (c == 4 && tx == NULL &&
+ (l & OMAP2_MCSPI_CHCONF_TURBO)) {
+ omap2_mcspi_set_enable(spi, 0);
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %08x\n",
+ word_len, *(rx - 1));
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_RXS) < 0) {
+ dev_err(&spi->dev,
+ "RXS timed out\n");
+ goto out;
+ }
+ c = 0;
+ } else if (c == 0 && tx == NULL) {
+ omap2_mcspi_set_enable(spi, 0);
+ }
+
+ *rx++ = readl_relaxed(rx_reg);
+ dev_vdbg(&spi->dev, "read-%d %08x\n",
+ word_len, *(rx - 1));
+ }
+ /* Add word delay between each word */
+ spi_delay_exec(&xfer->word_delay, xfer);
+ } while (c >= 4);
+ }
+
+ /* for TX_ONLY mode, be sure all words have shifted out */
+ if (xfer->rx_buf == NULL) {
+ if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_TXS) < 0) {
+ dev_err(&spi->dev, "TXS timed out\n");
+ } else if (mcspi_wait_for_reg_bit(chstat_reg,
+ OMAP2_MCSPI_CHSTAT_EOT) < 0)
+ dev_err(&spi->dev, "EOT timed out\n");
+
+ /* disable chan to purge rx datas received in TX_ONLY transfer,
+ * otherwise these rx datas will affect the direct following
+ * RX_ONLY transfer.
+ */
+ omap2_mcspi_set_enable(spi, 0);
+ }
+out:
+ omap2_mcspi_set_enable(spi, 1);
+ return count - c;
+}
+
+static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
+{
+ u32 div;
+
+ for (div = 0; div < 15; div++)
+ if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
+ return div;
+
+ return 15;
+}
+
+/* called only when no transfer is active to this device */
+static int omap2_mcspi_setup_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+ struct omap2_mcspi *mcspi;
+ u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
+ u8 word_len = spi->bits_per_word;
+ u32 speed_hz = spi->max_speed_hz;
+
+ mcspi = spi_master_get_devdata(spi->master);
+
+ if (t != NULL && t->bits_per_word)
+ word_len = t->bits_per_word;
+
+ cs->word_len = word_len;
+
+ if (t && t->speed_hz)
+ speed_hz = t->speed_hz;
+
+ speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
+ if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
+ clkd = omap2_mcspi_calc_divisor(speed_hz);
+ speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
+ clkg = 0;
+ } else {
+ div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
+ speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
+ clkd = (div - 1) & 0xf;
+ extclk = (div - 1) >> 4;
+ clkg = OMAP2_MCSPI_CHCONF_CLKG;
+ }
+
+ l = mcspi_cached_chconf0(spi);
+
+ /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
+ * REVISIT: this controller could support SPI_3WIRE mode.
+ */
+ if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
+ l &= ~OMAP2_MCSPI_CHCONF_IS;
+ l &= ~OMAP2_MCSPI_CHCONF_DPE1;
+ l |= OMAP2_MCSPI_CHCONF_DPE0;
+ } else {
+ l |= OMAP2_MCSPI_CHCONF_IS;
+ l |= OMAP2_MCSPI_CHCONF_DPE1;
+ l &= ~OMAP2_MCSPI_CHCONF_DPE0;
+ }
+
+ /* wordlength */
+ l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
+ l |= (word_len - 1) << 7;
+
+ /* set chipselect polarity; manage with FORCE */
+ if (!(spi->mode & SPI_CS_HIGH))
+ l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
+ else
+ l &= ~OMAP2_MCSPI_CHCONF_EPOL;
+
+ /* set clock divisor */
+ l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
+ l |= clkd << 2;
+
+ /* set clock granularity */
+ l &= ~OMAP2_MCSPI_CHCONF_CLKG;
+ l |= clkg;
+ if (clkg) {
+ cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
+ cs->chctrl0 |= extclk << 8;
+ mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
+ }
+
+ /* set SPI mode 0..3 */
+ if (spi->mode & SPI_CPOL)
+ l |= OMAP2_MCSPI_CHCONF_POL;
+ else
+ l &= ~OMAP2_MCSPI_CHCONF_POL;
+ if (spi->mode & SPI_CPHA)
+ l |= OMAP2_MCSPI_CHCONF_PHA;
+ else
+ l &= ~OMAP2_MCSPI_CHCONF_PHA;
+
+ mcspi_write_chconf0(spi, l);
+
+ cs->mode = spi->mode;
+
+ dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
+ speed_hz,
+ (spi->mode & SPI_CPHA) ? "trailing" : "leading",
+ (spi->mode & SPI_CPOL) ? "inverted" : "normal");
+
+ return 0;
+}
+
+/*
+ * Note that we currently allow DMA only if we get a channel
+ * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
+ */
+static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
+ struct omap2_mcspi_dma *mcspi_dma)
+{
+ int ret = 0;
+
+ mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
+ mcspi_dma->dma_rx_ch_name);
+ if (IS_ERR(mcspi_dma->dma_rx)) {
+ ret = PTR_ERR(mcspi_dma->dma_rx);
+ mcspi_dma->dma_rx = NULL;
+ goto no_dma;
+ }
+
+ mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
+ mcspi_dma->dma_tx_ch_name);
+ if (IS_ERR(mcspi_dma->dma_tx)) {
+ ret = PTR_ERR(mcspi_dma->dma_tx);
+ mcspi_dma->dma_tx = NULL;
+ dma_release_channel(mcspi_dma->dma_rx);
+ mcspi_dma->dma_rx = NULL;
+ }
+
+ init_completion(&mcspi_dma->dma_rx_completion);
+ init_completion(&mcspi_dma->dma_tx_completion);
+
+no_dma:
+ return ret;
+}
+
+static void omap2_mcspi_release_dma(struct spi_master *master)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_dma *mcspi_dma;
+ int i;
+
+ for (i = 0; i < master->num_chipselect; i++) {
+ mcspi_dma = &mcspi->dma_channels[i];
+
+ if (mcspi_dma->dma_rx) {
+ dma_release_channel(mcspi_dma->dma_rx);
+ mcspi_dma->dma_rx = NULL;
+ }
+ if (mcspi_dma->dma_tx) {
+ dma_release_channel(mcspi_dma->dma_tx);
+ mcspi_dma->dma_tx = NULL;
+ }
+ }
+}
+
+static void omap2_mcspi_cleanup(struct spi_device *spi)
+{
+ struct omap2_mcspi_cs *cs;
+
+ if (spi->controller_state) {
+ /* Unlink controller state from context save list */
+ cs = spi->controller_state;
+ list_del(&cs->node);
+
+ kfree(cs);
+ }
+}
+
+static int omap2_mcspi_setup(struct spi_device *spi)
+{
+ bool initial_setup = false;
+ int ret;
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ struct omap2_mcspi_cs *cs = spi->controller_state;
+
+ if (!cs) {
+ cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+ if (!cs)
+ return -ENOMEM;
+ cs->base = mcspi->base + spi->chip_select * 0x14;
+ cs->phys = mcspi->phys + spi->chip_select * 0x14;
+ cs->mode = 0;
+ cs->chconf0 = 0;
+ cs->chctrl0 = 0;
+ spi->controller_state = cs;
+ /* Link this to context save list */
+ list_add_tail(&cs->node, &ctx->cs);
+ initial_setup = true;
+ }
+
+ ret = pm_runtime_resume_and_get(mcspi->dev);
+ if (ret < 0) {
+ if (initial_setup)
+ omap2_mcspi_cleanup(spi);
+
+ return ret;
+ }
+
+ ret = omap2_mcspi_setup_transfer(spi, NULL);
+ if (ret && initial_setup)
+ omap2_mcspi_cleanup(spi);
+
+ pm_runtime_mark_last_busy(mcspi->dev);
+ pm_runtime_put_autosuspend(mcspi->dev);
+
+ return ret;
+}
+
+static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
+{
+ struct omap2_mcspi *mcspi = data;
+ u32 irqstat;
+
+ irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
+ if (!irqstat)
+ return IRQ_NONE;
+
+ /* Disable IRQ and wakeup slave xfer task */
+ mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
+ if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
+ complete(&mcspi->txdone);
+
+ return IRQ_HANDLED;
+}
+
+static int omap2_mcspi_slave_abort(struct spi_master *master)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
+
+ mcspi->slave_aborted = true;
+ complete(&mcspi_dma->dma_rx_completion);
+ complete(&mcspi_dma->dma_tx_completion);
+ complete(&mcspi->txdone);
+
+ return 0;
+}
+
+static int omap2_mcspi_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
+{
+
+ /* We only enable one channel at a time -- the one whose message is
+ * -- although this controller would gladly
+ * arbitrate among multiple channels. This corresponds to "single
+ * channel" master mode. As a side effect, we need to manage the
+ * chipselect with the FORCE bit ... CS != channel enable.
+ */
+
+ struct omap2_mcspi *mcspi;
+ struct omap2_mcspi_dma *mcspi_dma;
+ struct omap2_mcspi_cs *cs;
+ struct omap2_mcspi_device_config *cd;
+ int par_override = 0;
+ int status = 0;
+ u32 chconf;
+
+ mcspi = spi_master_get_devdata(master);
+ mcspi_dma = mcspi->dma_channels + spi->chip_select;
+ cs = spi->controller_state;
+ cd = spi->controller_data;
+
+ /*
+ * The slave driver could have changed spi->mode in which case
+ * it will be different from cs->mode (the current hardware setup).
+ * If so, set par_override (even though its not a parity issue) so
+ * omap2_mcspi_setup_transfer will be called to configure the hardware
+ * with the correct mode on the first iteration of the loop below.
+ */
+ if (spi->mode != cs->mode)
+ par_override = 1;
+
+ omap2_mcspi_set_enable(spi, 0);
+
+ if (spi->cs_gpiod)
+ omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
+
+ if (par_override ||
+ (t->speed_hz != spi->max_speed_hz) ||
+ (t->bits_per_word != spi->bits_per_word)) {
+ par_override = 1;
+ status = omap2_mcspi_setup_transfer(spi, t);
+ if (status < 0)
+ goto out;
+ if (t->speed_hz == spi->max_speed_hz &&
+ t->bits_per_word == spi->bits_per_word)
+ par_override = 0;
+ }
+ if (cd && cd->cs_per_word) {
+ chconf = mcspi->ctx.modulctrl;
+ chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
+ mcspi->ctx.modulctrl =
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
+ }
+
+ chconf = mcspi_cached_chconf0(spi);
+ chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
+ chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
+
+ if (t->tx_buf == NULL)
+ chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
+ else if (t->rx_buf == NULL)
+ chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
+
+ if (cd && cd->turbo_mode && t->tx_buf == NULL) {
+ /* Turbo mode is for more than one word */
+ if (t->len > ((cs->word_len + 7) >> 3))
+ chconf |= OMAP2_MCSPI_CHCONF_TURBO;
+ }
+
+ mcspi_write_chconf0(spi, chconf);
+
+ if (t->len) {
+ unsigned count;
+
+ if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
+ master->cur_msg_mapped &&
+ master->can_dma(master, spi, t))
+ omap2_mcspi_set_fifo(spi, t, 1);
+
+ omap2_mcspi_set_enable(spi, 1);
+
+ /* RX_ONLY mode needs dummy data in TX reg */
+ if (t->tx_buf == NULL)
+ writel_relaxed(0, cs->base
+ + OMAP2_MCSPI_TX0);
+
+ if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
+ master->cur_msg_mapped &&
+ master->can_dma(master, spi, t))
+ count = omap2_mcspi_txrx_dma(spi, t);
+ else
+ count = omap2_mcspi_txrx_pio(spi, t);
+
+ if (count != t->len) {
+ status = -EIO;
+ goto out;
+ }
+ }
+
+ omap2_mcspi_set_enable(spi, 0);
+
+ if (mcspi->fifo_depth > 0)
+ omap2_mcspi_set_fifo(spi, t, 0);
+
+out:
+ /* Restore defaults if they were overriden */
+ if (par_override) {
+ par_override = 0;
+ status = omap2_mcspi_setup_transfer(spi, NULL);
+ }
+
+ if (cd && cd->cs_per_word) {
+ chconf = mcspi->ctx.modulctrl;
+ chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
+ mcspi->ctx.modulctrl =
+ mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
+ }
+
+ omap2_mcspi_set_enable(spi, 0);
+
+ if (spi->cs_gpiod)
+ omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
+
+ if (mcspi->fifo_depth > 0 && t)
+ omap2_mcspi_set_fifo(spi, t, 0);
+
+ return status;
+}
+
+static int omap2_mcspi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ struct omap2_mcspi_cs *cs;
+
+ /* Only a single channel can have the FORCE bit enabled
+ * in its chconf0 register.
+ * Scan all channels and disable them except the current one.
+ * A FORCE can remain from a last transfer having cs_change enabled
+ */
+ list_for_each_entry(cs, &ctx->cs, node) {
+ if (msg->spi->controller_state == cs)
+ continue;
+
+ if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
+ cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ writel_relaxed(cs->chconf0,
+ cs->base + OMAP2_MCSPI_CHCONF0);
+ readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
+ }
+ }
+
+ return 0;
+}
+
+static bool omap2_mcspi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ struct omap2_mcspi_dma *mcspi_dma =
+ &mcspi->dma_channels[spi->chip_select];
+
+ if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
+ return false;
+
+ if (spi_controller_is_slave(master))
+ return true;
+
+ master->dma_rx = mcspi_dma->dma_rx;
+ master->dma_tx = mcspi_dma->dma_tx;
+
+ return (xfer->len >= DMA_MIN_BYTES);
+}
+
+static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
+{
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
+ struct omap2_mcspi_dma *mcspi_dma =
+ &mcspi->dma_channels[spi->chip_select];
+
+ if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
+ return mcspi->max_xfer_len;
+
+ return SIZE_MAX;
+}
+
+static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
+{
+ struct spi_master *master = mcspi->master;
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ int ret = 0;
+
+ ret = pm_runtime_resume_and_get(mcspi->dev);
+ if (ret < 0)
+ return ret;
+
+ mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
+ OMAP2_MCSPI_WAKEUPENABLE_WKEN);
+ ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
+
+ omap2_mcspi_set_mode(master);
+ pm_runtime_mark_last_busy(mcspi->dev);
+ pm_runtime_put_autosuspend(mcspi->dev);
+ return 0;
+}
+
+static int omap_mcspi_runtime_suspend(struct device *dev)
+{
+ int error;
+
+ error = pinctrl_pm_select_idle_state(dev);
+ if (error)
+ dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
+
+ return 0;
+}
+
+/*
+ * When SPI wake up from off-mode, CS is in activate state. If it was in
+ * inactive state when driver was suspend, then force it to inactive state at
+ * wake up.
+ */
+static int omap_mcspi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ struct omap2_mcspi_regs *ctx = &mcspi->ctx;
+ struct omap2_mcspi_cs *cs;
+ int error;
+
+ error = pinctrl_pm_select_default_state(dev);
+ if (error)
+ dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
+
+ /* McSPI: context restore */
+ mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
+ mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
+
+ list_for_each_entry(cs, &ctx->cs, node) {
+ /*
+ * We need to toggle CS state for OMAP take this
+ * change in account.
+ */
+ if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
+ cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
+ writel_relaxed(cs->chconf0,
+ cs->base + OMAP2_MCSPI_CHCONF0);
+ cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
+ writel_relaxed(cs->chconf0,
+ cs->base + OMAP2_MCSPI_CHCONF0);
+ } else {
+ writel_relaxed(cs->chconf0,
+ cs->base + OMAP2_MCSPI_CHCONF0);
+ }
+ }
+
+ return 0;
+}
+
+static struct omap2_mcspi_platform_config omap2_pdata = {
+ .regs_offset = 0,
+};
+
+static struct omap2_mcspi_platform_config omap4_pdata = {
+ .regs_offset = OMAP4_MCSPI_REG_OFFSET,
+};
+
+static struct omap2_mcspi_platform_config am654_pdata = {
+ .regs_offset = OMAP4_MCSPI_REG_OFFSET,
+ .max_xfer_len = SZ_4K - 1,
+};
+
+static const struct of_device_id omap_mcspi_of_match[] = {
+ {
+ .compatible = "ti,omap2-mcspi",
+ .data = &omap2_pdata,
+ },
+ {
+ .compatible = "ti,omap4-mcspi",
+ .data = &omap4_pdata,
+ },
+ {
+ .compatible = "ti,am654-mcspi",
+ .data = &am654_pdata,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
+
+static int omap2_mcspi_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ const struct omap2_mcspi_platform_config *pdata;
+ struct omap2_mcspi *mcspi;
+ struct resource *r;
+ int status = 0, i;
+ u32 regs_offset = 0;
+ struct device_node *node = pdev->dev.of_node;
+ const struct of_device_id *match;
+
+ if (of_property_read_bool(node, "spi-slave"))
+ master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
+ else
+ master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
+ if (!master)
+ return -ENOMEM;
+
+ /* the spi->mode bits understood by this driver: */
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+ master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
+ master->setup = omap2_mcspi_setup;
+ master->auto_runtime_pm = true;
+ master->prepare_message = omap2_mcspi_prepare_message;
+ master->can_dma = omap2_mcspi_can_dma;
+ master->transfer_one = omap2_mcspi_transfer_one;
+ master->set_cs = omap2_mcspi_set_cs;
+ master->cleanup = omap2_mcspi_cleanup;
+ master->slave_abort = omap2_mcspi_slave_abort;
+ master->dev.of_node = node;
+ master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
+ master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
+ master->use_gpio_descriptors = true;
+
+ platform_set_drvdata(pdev, master);
+
+ mcspi = spi_master_get_devdata(master);
+ mcspi->master = master;
+
+ match = of_match_device(omap_mcspi_of_match, &pdev->dev);
+ if (match) {
+ u32 num_cs = 1; /* default number of chipselect */
+ pdata = match->data;
+
+ of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
+ master->num_chipselect = num_cs;
+ if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
+ mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
+ } else {
+ pdata = dev_get_platdata(&pdev->dev);
+ master->num_chipselect = pdata->num_cs;
+ mcspi->pin_dir = pdata->pin_dir;
+ }
+ regs_offset = pdata->regs_offset;
+ if (pdata->max_xfer_len) {
+ mcspi->max_xfer_len = pdata->max_xfer_len;
+ master->max_transfer_size = omap2_mcspi_max_xfer_size;
+ }
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mcspi->base = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(mcspi->base)) {
+ status = PTR_ERR(mcspi->base);
+ goto free_master;
+ }
+ mcspi->phys = r->start + regs_offset;
+ mcspi->base += regs_offset;
+
+ mcspi->dev = &pdev->dev;
+
+ INIT_LIST_HEAD(&mcspi->ctx.cs);
+
+ mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
+ sizeof(struct omap2_mcspi_dma),
+ GFP_KERNEL);
+ if (mcspi->dma_channels == NULL) {
+ status = -ENOMEM;
+ goto free_master;
+ }
+
+ for (i = 0; i < master->num_chipselect; i++) {
+ sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
+ sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
+
+ status = omap2_mcspi_request_dma(mcspi,
+ &mcspi->dma_channels[i]);
+ if (status == -EPROBE_DEFER)
+ goto free_master;
+ }
+
+ status = platform_get_irq(pdev, 0);
+ if (status < 0) {
+ dev_err_probe(&pdev->dev, status, "no irq resource found\n");
+ goto free_master;
+ }
+ init_completion(&mcspi->txdone);
+ status = devm_request_irq(&pdev->dev, status,
+ omap2_mcspi_irq_handler, 0, pdev->name,
+ mcspi);
+ if (status) {
+ dev_err(&pdev->dev, "Cannot request IRQ");
+ goto free_master;
+ }
+
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
+ pm_runtime_enable(&pdev->dev);
+
+ status = omap2_mcspi_controller_setup(mcspi);
+ if (status < 0)
+ goto disable_pm;
+
+ status = devm_spi_register_controller(&pdev->dev, master);
+ if (status < 0)
+ goto disable_pm;
+
+ return status;
+
+disable_pm:
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+free_master:
+ omap2_mcspi_release_dma(master);
+ spi_master_put(master);
+ return status;
+}
+
+static int omap2_mcspi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+
+ omap2_mcspi_release_dma(master);
+
+ pm_runtime_dont_use_autosuspend(mcspi->dev);
+ pm_runtime_put_sync(mcspi->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:omap2_mcspi");
+
+static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ int error;
+
+ error = pinctrl_pm_select_sleep_state(dev);
+ if (error)
+ dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
+ __func__, error);
+
+ error = spi_master_suspend(master);
+ if (error)
+ dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
+ __func__, error);
+
+ return pm_runtime_force_suspend(dev);
+}
+
+static int __maybe_unused omap2_mcspi_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
+ int error;
+
+ error = spi_master_resume(master);
+ if (error)
+ dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
+ __func__, error);
+
+ return pm_runtime_force_resume(dev);
+}
+
+static const struct dev_pm_ops omap2_mcspi_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
+ omap2_mcspi_resume)
+ .runtime_suspend = omap_mcspi_runtime_suspend,
+ .runtime_resume = omap_mcspi_runtime_resume,
+};
+
+static struct platform_driver omap2_mcspi_driver = {
+ .driver = {
+ .name = "omap2_mcspi",
+ .pm = &omap2_mcspi_pm_ops,
+ .of_match_table = omap_mcspi_of_match,
+ },
+ .probe = omap2_mcspi_probe,
+ .remove = omap2_mcspi_remove,
+};
+
+module_platform_driver(omap2_mcspi_driver);
+MODULE_LICENSE("GPL");