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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/spi/spi-rockchip.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--drivers/spi/spi-rockchip.c952
1 files changed, 952 insertions, 0 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
new file mode 100644
index 000000000..a9f97023d
--- /dev/null
+++ b/drivers/spi/spi-rockchip.c
@@ -0,0 +1,952 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ * Author: Addy Ke <addy.ke@rock-chips.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
+#include <linux/scatterlist.h>
+
+#define DRIVER_NAME "rockchip-spi"
+
+#define ROCKCHIP_SPI_CLR_BITS(reg, bits) \
+ writel_relaxed(readl_relaxed(reg) & ~(bits), reg)
+#define ROCKCHIP_SPI_SET_BITS(reg, bits) \
+ writel_relaxed(readl_relaxed(reg) | (bits), reg)
+
+/* SPI register offsets */
+#define ROCKCHIP_SPI_CTRLR0 0x0000
+#define ROCKCHIP_SPI_CTRLR1 0x0004
+#define ROCKCHIP_SPI_SSIENR 0x0008
+#define ROCKCHIP_SPI_SER 0x000c
+#define ROCKCHIP_SPI_BAUDR 0x0010
+#define ROCKCHIP_SPI_TXFTLR 0x0014
+#define ROCKCHIP_SPI_RXFTLR 0x0018
+#define ROCKCHIP_SPI_TXFLR 0x001c
+#define ROCKCHIP_SPI_RXFLR 0x0020
+#define ROCKCHIP_SPI_SR 0x0024
+#define ROCKCHIP_SPI_IPR 0x0028
+#define ROCKCHIP_SPI_IMR 0x002c
+#define ROCKCHIP_SPI_ISR 0x0030
+#define ROCKCHIP_SPI_RISR 0x0034
+#define ROCKCHIP_SPI_ICR 0x0038
+#define ROCKCHIP_SPI_DMACR 0x003c
+#define ROCKCHIP_SPI_DMATDLR 0x0040
+#define ROCKCHIP_SPI_DMARDLR 0x0044
+#define ROCKCHIP_SPI_VERSION 0x0048
+#define ROCKCHIP_SPI_TXDR 0x0400
+#define ROCKCHIP_SPI_RXDR 0x0800
+
+/* Bit fields in CTRLR0 */
+#define CR0_DFS_OFFSET 0
+#define CR0_DFS_4BIT 0x0
+#define CR0_DFS_8BIT 0x1
+#define CR0_DFS_16BIT 0x2
+
+#define CR0_CFS_OFFSET 2
+
+#define CR0_SCPH_OFFSET 6
+
+#define CR0_SCPOL_OFFSET 7
+
+#define CR0_CSM_OFFSET 8
+#define CR0_CSM_KEEP 0x0
+/* ss_n be high for half sclk_out cycles */
+#define CR0_CSM_HALF 0X1
+/* ss_n be high for one sclk_out cycle */
+#define CR0_CSM_ONE 0x2
+
+/* ss_n to sclk_out delay */
+#define CR0_SSD_OFFSET 10
+/*
+ * The period between ss_n active and
+ * sclk_out active is half sclk_out cycles
+ */
+#define CR0_SSD_HALF 0x0
+/*
+ * The period between ss_n active and
+ * sclk_out active is one sclk_out cycle
+ */
+#define CR0_SSD_ONE 0x1
+
+#define CR0_EM_OFFSET 11
+#define CR0_EM_LITTLE 0x0
+#define CR0_EM_BIG 0x1
+
+#define CR0_FBM_OFFSET 12
+#define CR0_FBM_MSB 0x0
+#define CR0_FBM_LSB 0x1
+
+#define CR0_BHT_OFFSET 13
+#define CR0_BHT_16BIT 0x0
+#define CR0_BHT_8BIT 0x1
+
+#define CR0_RSD_OFFSET 14
+#define CR0_RSD_MAX 0x3
+
+#define CR0_FRF_OFFSET 16
+#define CR0_FRF_SPI 0x0
+#define CR0_FRF_SSP 0x1
+#define CR0_FRF_MICROWIRE 0x2
+
+#define CR0_XFM_OFFSET 18
+#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET)
+#define CR0_XFM_TR 0x0
+#define CR0_XFM_TO 0x1
+#define CR0_XFM_RO 0x2
+
+#define CR0_OPM_OFFSET 20
+#define CR0_OPM_MASTER 0x0
+#define CR0_OPM_SLAVE 0x1
+
+#define CR0_MTM_OFFSET 0x21
+
+/* Bit fields in SER, 2bit */
+#define SER_MASK 0x3
+
+/* Bit fields in BAUDR */
+#define BAUDR_SCKDV_MIN 2
+#define BAUDR_SCKDV_MAX 65534
+
+/* Bit fields in SR, 5bit */
+#define SR_MASK 0x1f
+#define SR_BUSY (1 << 0)
+#define SR_TF_FULL (1 << 1)
+#define SR_TF_EMPTY (1 << 2)
+#define SR_RF_EMPTY (1 << 3)
+#define SR_RF_FULL (1 << 4)
+
+/* Bit fields in ISR, IMR, ISR, RISR, 5bit */
+#define INT_MASK 0x1f
+#define INT_TF_EMPTY (1 << 0)
+#define INT_TF_OVERFLOW (1 << 1)
+#define INT_RF_UNDERFLOW (1 << 2)
+#define INT_RF_OVERFLOW (1 << 3)
+#define INT_RF_FULL (1 << 4)
+
+/* Bit fields in ICR, 4bit */
+#define ICR_MASK 0x0f
+#define ICR_ALL (1 << 0)
+#define ICR_RF_UNDERFLOW (1 << 1)
+#define ICR_RF_OVERFLOW (1 << 2)
+#define ICR_TF_OVERFLOW (1 << 3)
+
+/* Bit fields in DMACR */
+#define RF_DMA_EN (1 << 0)
+#define TF_DMA_EN (1 << 1)
+
+/* Driver state flags */
+#define RXDMA (1 << 0)
+#define TXDMA (1 << 1)
+
+/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
+#define MAX_SCLK_OUT 50000000U
+
+/*
+ * SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However,
+ * the controller seems to hang when given 0x10000, so stick with this for now.
+ */
+#define ROCKCHIP_SPI_MAX_TRANLEN 0xffff
+
+#define ROCKCHIP_SPI_MAX_CS_NUM 2
+#define ROCKCHIP_SPI_VER2_TYPE1 0x05EC0002
+#define ROCKCHIP_SPI_VER2_TYPE2 0x00110002
+
+struct rockchip_spi {
+ struct device *dev;
+
+ struct clk *spiclk;
+ struct clk *apb_pclk;
+
+ void __iomem *regs;
+ dma_addr_t dma_addr_rx;
+ dma_addr_t dma_addr_tx;
+
+ const void *tx;
+ void *rx;
+ unsigned int tx_left;
+ unsigned int rx_left;
+
+ atomic_t state;
+
+ /*depth of the FIFO buffer */
+ u32 fifo_len;
+ /* frequency of spiclk */
+ u32 freq;
+
+ u8 n_bytes;
+ u8 rsd;
+
+ bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM];
+
+ bool slave_abort;
+};
+
+static inline void spi_enable_chip(struct rockchip_spi *rs, bool enable)
+{
+ writel_relaxed((enable ? 1U : 0U), rs->regs + ROCKCHIP_SPI_SSIENR);
+}
+
+static inline void wait_for_idle(struct rockchip_spi *rs)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(5);
+
+ do {
+ if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
+ return;
+ } while (!time_after(jiffies, timeout));
+
+ dev_warn(rs->dev, "spi controller is in busy state!\n");
+}
+
+static u32 get_fifo_len(struct rockchip_spi *rs)
+{
+ u32 ver;
+
+ ver = readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION);
+
+ switch (ver) {
+ case ROCKCHIP_SPI_VER2_TYPE1:
+ case ROCKCHIP_SPI_VER2_TYPE2:
+ return 64;
+ default:
+ return 32;
+ }
+}
+
+static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct spi_controller *ctlr = spi->controller;
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+ bool cs_asserted = !enable;
+
+ /* Return immediately for no-op */
+ if (cs_asserted == rs->cs_asserted[spi->chip_select])
+ return;
+
+ if (cs_asserted) {
+ /* Keep things powered as long as CS is asserted */
+ pm_runtime_get_sync(rs->dev);
+
+ ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER,
+ BIT(spi->chip_select));
+ } else {
+ ROCKCHIP_SPI_CLR_BITS(rs->regs + ROCKCHIP_SPI_SER,
+ BIT(spi->chip_select));
+
+ /* Drop reference from when we first asserted CS */
+ pm_runtime_put(rs->dev);
+ }
+
+ rs->cs_asserted[spi->chip_select] = cs_asserted;
+}
+
+static void rockchip_spi_handle_err(struct spi_controller *ctlr,
+ struct spi_message *msg)
+{
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ /* stop running spi transfer
+ * this also flushes both rx and tx fifos
+ */
+ spi_enable_chip(rs, false);
+
+ /* make sure all interrupts are masked */
+ writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR);
+
+ if (atomic_read(&rs->state) & TXDMA)
+ dmaengine_terminate_async(ctlr->dma_tx);
+
+ if (atomic_read(&rs->state) & RXDMA)
+ dmaengine_terminate_async(ctlr->dma_rx);
+}
+
+static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
+{
+ u32 tx_free = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
+ u32 words = min(rs->tx_left, tx_free);
+
+ rs->tx_left -= words;
+ for (; words; words--) {
+ u32 txw;
+
+ if (rs->n_bytes == 1)
+ txw = *(u8 *)rs->tx;
+ else
+ txw = *(u16 *)rs->tx;
+
+ writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
+ rs->tx += rs->n_bytes;
+ }
+}
+
+static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
+{
+ u32 words = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
+ u32 rx_left = (rs->rx_left > words) ? rs->rx_left - words : 0;
+
+ /* the hardware doesn't allow us to change fifo threshold
+ * level while spi is enabled, so instead make sure to leave
+ * enough words in the rx fifo to get the last interrupt
+ * exactly when all words have been received
+ */
+ if (rx_left) {
+ u32 ftl = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFTLR) + 1;
+
+ if (rx_left < ftl) {
+ rx_left = ftl;
+ words = rs->rx_left - rx_left;
+ }
+ }
+
+ rs->rx_left = rx_left;
+ for (; words; words--) {
+ u32 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
+
+ if (!rs->rx)
+ continue;
+
+ if (rs->n_bytes == 1)
+ *(u8 *)rs->rx = (u8)rxw;
+ else
+ *(u16 *)rs->rx = (u16)rxw;
+ rs->rx += rs->n_bytes;
+ }
+}
+
+static irqreturn_t rockchip_spi_isr(int irq, void *dev_id)
+{
+ struct spi_controller *ctlr = dev_id;
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ if (rs->tx_left)
+ rockchip_spi_pio_writer(rs);
+
+ rockchip_spi_pio_reader(rs);
+ if (!rs->rx_left) {
+ spi_enable_chip(rs, false);
+ writel_relaxed(0, rs->regs + ROCKCHIP_SPI_IMR);
+ spi_finalize_current_transfer(ctlr);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int rockchip_spi_prepare_irq(struct rockchip_spi *rs,
+ struct spi_transfer *xfer)
+{
+ rs->tx = xfer->tx_buf;
+ rs->rx = xfer->rx_buf;
+ rs->tx_left = rs->tx ? xfer->len / rs->n_bytes : 0;
+ rs->rx_left = xfer->len / rs->n_bytes;
+
+ writel_relaxed(INT_RF_FULL, rs->regs + ROCKCHIP_SPI_IMR);
+ spi_enable_chip(rs, true);
+
+ if (rs->tx_left)
+ rockchip_spi_pio_writer(rs);
+
+ /* 1 means the transfer is in progress */
+ return 1;
+}
+
+static void rockchip_spi_dma_rxcb(void *data)
+{
+ struct spi_controller *ctlr = data;
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+ int state = atomic_fetch_andnot(RXDMA, &rs->state);
+
+ if (state & TXDMA && !rs->slave_abort)
+ return;
+
+ spi_enable_chip(rs, false);
+ spi_finalize_current_transfer(ctlr);
+}
+
+static void rockchip_spi_dma_txcb(void *data)
+{
+ struct spi_controller *ctlr = data;
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+ int state = atomic_fetch_andnot(TXDMA, &rs->state);
+
+ if (state & RXDMA && !rs->slave_abort)
+ return;
+
+ /* Wait until the FIFO data completely. */
+ wait_for_idle(rs);
+
+ spi_enable_chip(rs, false);
+ spi_finalize_current_transfer(ctlr);
+}
+
+static u32 rockchip_spi_calc_burst_size(u32 data_len)
+{
+ u32 i;
+
+ /* burst size: 1, 2, 4, 8 */
+ for (i = 1; i < 8; i <<= 1) {
+ if (data_len & i)
+ break;
+ }
+
+ return i;
+}
+
+static int rockchip_spi_prepare_dma(struct rockchip_spi *rs,
+ struct spi_controller *ctlr, struct spi_transfer *xfer)
+{
+ struct dma_async_tx_descriptor *rxdesc, *txdesc;
+
+ atomic_set(&rs->state, 0);
+
+ rxdesc = NULL;
+ if (xfer->rx_buf) {
+ struct dma_slave_config rxconf = {
+ .direction = DMA_DEV_TO_MEM,
+ .src_addr = rs->dma_addr_rx,
+ .src_addr_width = rs->n_bytes,
+ .src_maxburst = rockchip_spi_calc_burst_size(xfer->len /
+ rs->n_bytes),
+ };
+
+ dmaengine_slave_config(ctlr->dma_rx, &rxconf);
+
+ rxdesc = dmaengine_prep_slave_sg(
+ ctlr->dma_rx,
+ xfer->rx_sg.sgl, xfer->rx_sg.nents,
+ DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
+ if (!rxdesc)
+ return -EINVAL;
+
+ rxdesc->callback = rockchip_spi_dma_rxcb;
+ rxdesc->callback_param = ctlr;
+ }
+
+ txdesc = NULL;
+ if (xfer->tx_buf) {
+ struct dma_slave_config txconf = {
+ .direction = DMA_MEM_TO_DEV,
+ .dst_addr = rs->dma_addr_tx,
+ .dst_addr_width = rs->n_bytes,
+ .dst_maxburst = rs->fifo_len / 4,
+ };
+
+ dmaengine_slave_config(ctlr->dma_tx, &txconf);
+
+ txdesc = dmaengine_prep_slave_sg(
+ ctlr->dma_tx,
+ xfer->tx_sg.sgl, xfer->tx_sg.nents,
+ DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
+ if (!txdesc) {
+ if (rxdesc)
+ dmaengine_terminate_sync(ctlr->dma_rx);
+ return -EINVAL;
+ }
+
+ txdesc->callback = rockchip_spi_dma_txcb;
+ txdesc->callback_param = ctlr;
+ }
+
+ /* rx must be started before tx due to spi instinct */
+ if (rxdesc) {
+ atomic_or(RXDMA, &rs->state);
+ dmaengine_submit(rxdesc);
+ dma_async_issue_pending(ctlr->dma_rx);
+ }
+
+ spi_enable_chip(rs, true);
+
+ if (txdesc) {
+ atomic_or(TXDMA, &rs->state);
+ dmaengine_submit(txdesc);
+ dma_async_issue_pending(ctlr->dma_tx);
+ }
+
+ /* 1 means the transfer is in progress */
+ return 1;
+}
+
+static int rockchip_spi_config(struct rockchip_spi *rs,
+ struct spi_device *spi, struct spi_transfer *xfer,
+ bool use_dma, bool slave_mode)
+{
+ u32 cr0 = CR0_FRF_SPI << CR0_FRF_OFFSET
+ | CR0_BHT_8BIT << CR0_BHT_OFFSET
+ | CR0_SSD_ONE << CR0_SSD_OFFSET
+ | CR0_EM_BIG << CR0_EM_OFFSET;
+ u32 cr1;
+ u32 dmacr = 0;
+
+ if (slave_mode)
+ cr0 |= CR0_OPM_SLAVE << CR0_OPM_OFFSET;
+ rs->slave_abort = false;
+
+ cr0 |= rs->rsd << CR0_RSD_OFFSET;
+ cr0 |= (spi->mode & 0x3U) << CR0_SCPH_OFFSET;
+ if (spi->mode & SPI_LSB_FIRST)
+ cr0 |= CR0_FBM_LSB << CR0_FBM_OFFSET;
+
+ if (xfer->rx_buf && xfer->tx_buf)
+ cr0 |= CR0_XFM_TR << CR0_XFM_OFFSET;
+ else if (xfer->rx_buf)
+ cr0 |= CR0_XFM_RO << CR0_XFM_OFFSET;
+ else if (use_dma)
+ cr0 |= CR0_XFM_TO << CR0_XFM_OFFSET;
+
+ switch (xfer->bits_per_word) {
+ case 4:
+ cr0 |= CR0_DFS_4BIT << CR0_DFS_OFFSET;
+ cr1 = xfer->len - 1;
+ break;
+ case 8:
+ cr0 |= CR0_DFS_8BIT << CR0_DFS_OFFSET;
+ cr1 = xfer->len - 1;
+ break;
+ case 16:
+ cr0 |= CR0_DFS_16BIT << CR0_DFS_OFFSET;
+ cr1 = xfer->len / 2 - 1;
+ break;
+ default:
+ /* we only whitelist 4, 8 and 16 bit words in
+ * ctlr->bits_per_word_mask, so this shouldn't
+ * happen
+ */
+ dev_err(rs->dev, "unknown bits per word: %d\n",
+ xfer->bits_per_word);
+ return -EINVAL;
+ }
+
+ if (use_dma) {
+ if (xfer->tx_buf)
+ dmacr |= TF_DMA_EN;
+ if (xfer->rx_buf)
+ dmacr |= RF_DMA_EN;
+ }
+
+ writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
+ writel_relaxed(cr1, rs->regs + ROCKCHIP_SPI_CTRLR1);
+
+ /* unfortunately setting the fifo threshold level to generate an
+ * interrupt exactly when the fifo is full doesn't seem to work,
+ * so we need the strict inequality here
+ */
+ if (xfer->len < rs->fifo_len)
+ writel_relaxed(xfer->len - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
+ else
+ writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
+
+ writel_relaxed(rs->fifo_len / 2, rs->regs + ROCKCHIP_SPI_DMATDLR);
+ writel_relaxed(rockchip_spi_calc_burst_size(xfer->len / rs->n_bytes) - 1,
+ rs->regs + ROCKCHIP_SPI_DMARDLR);
+ writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
+
+ /* the hardware only supports an even clock divisor, so
+ * round divisor = spiclk / speed up to nearest even number
+ * so that the resulting speed is <= the requested speed
+ */
+ writel_relaxed(2 * DIV_ROUND_UP(rs->freq, 2 * xfer->speed_hz),
+ rs->regs + ROCKCHIP_SPI_BAUDR);
+
+ return 0;
+}
+
+static size_t rockchip_spi_max_transfer_size(struct spi_device *spi)
+{
+ return ROCKCHIP_SPI_MAX_TRANLEN;
+}
+
+static int rockchip_spi_slave_abort(struct spi_controller *ctlr)
+{
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ if (atomic_read(&rs->state) & RXDMA)
+ dmaengine_terminate_sync(ctlr->dma_rx);
+ if (atomic_read(&rs->state) & TXDMA)
+ dmaengine_terminate_sync(ctlr->dma_tx);
+ atomic_set(&rs->state, 0);
+ spi_enable_chip(rs, false);
+ rs->slave_abort = true;
+ complete(&ctlr->xfer_completion);
+
+ return 0;
+}
+
+static int rockchip_spi_transfer_one(
+ struct spi_controller *ctlr,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+ int ret;
+ bool use_dma;
+
+ /* Zero length transfers won't trigger an interrupt on completion */
+ if (!xfer->len) {
+ spi_finalize_current_transfer(ctlr);
+ return 1;
+ }
+
+ WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
+ (readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
+
+ if (!xfer->tx_buf && !xfer->rx_buf) {
+ dev_err(rs->dev, "No buffer for transfer\n");
+ return -EINVAL;
+ }
+
+ if (xfer->len > ROCKCHIP_SPI_MAX_TRANLEN) {
+ dev_err(rs->dev, "Transfer is too long (%d)\n", xfer->len);
+ return -EINVAL;
+ }
+
+ rs->n_bytes = xfer->bits_per_word <= 8 ? 1 : 2;
+
+ use_dma = ctlr->can_dma ? ctlr->can_dma(ctlr, spi, xfer) : false;
+
+ ret = rockchip_spi_config(rs, spi, xfer, use_dma, ctlr->slave);
+ if (ret)
+ return ret;
+
+ if (use_dma)
+ return rockchip_spi_prepare_dma(rs, ctlr, xfer);
+
+ return rockchip_spi_prepare_irq(rs, xfer);
+}
+
+static bool rockchip_spi_can_dma(struct spi_controller *ctlr,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+ unsigned int bytes_per_word = xfer->bits_per_word <= 8 ? 1 : 2;
+
+ /* if the numbor of spi words to transfer is less than the fifo
+ * length we can just fill the fifo and wait for a single irq,
+ * so don't bother setting up dma
+ */
+ return xfer->len / bytes_per_word >= rs->fifo_len;
+}
+
+static int rockchip_spi_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct rockchip_spi *rs;
+ struct spi_controller *ctlr;
+ struct resource *mem;
+ struct device_node *np = pdev->dev.of_node;
+ u32 rsd_nsecs, num_cs;
+ bool slave_mode;
+
+ slave_mode = of_property_read_bool(np, "spi-slave");
+
+ if (slave_mode)
+ ctlr = spi_alloc_slave(&pdev->dev,
+ sizeof(struct rockchip_spi));
+ else
+ ctlr = spi_alloc_master(&pdev->dev,
+ sizeof(struct rockchip_spi));
+
+ if (!ctlr)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ctlr);
+
+ rs = spi_controller_get_devdata(ctlr);
+ ctlr->slave = slave_mode;
+
+ /* Get basic io resource and map it */
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rs->regs = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(rs->regs)) {
+ ret = PTR_ERR(rs->regs);
+ goto err_put_ctlr;
+ }
+
+ rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
+ if (IS_ERR(rs->apb_pclk)) {
+ dev_err(&pdev->dev, "Failed to get apb_pclk\n");
+ ret = PTR_ERR(rs->apb_pclk);
+ goto err_put_ctlr;
+ }
+
+ rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
+ if (IS_ERR(rs->spiclk)) {
+ dev_err(&pdev->dev, "Failed to get spi_pclk\n");
+ ret = PTR_ERR(rs->spiclk);
+ goto err_put_ctlr;
+ }
+
+ ret = clk_prepare_enable(rs->apb_pclk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
+ goto err_put_ctlr;
+ }
+
+ ret = clk_prepare_enable(rs->spiclk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to enable spi_clk\n");
+ goto err_disable_apbclk;
+ }
+
+ spi_enable_chip(rs, false);
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ goto err_disable_spiclk;
+
+ ret = devm_request_threaded_irq(&pdev->dev, ret, rockchip_spi_isr, NULL,
+ IRQF_ONESHOT, dev_name(&pdev->dev), ctlr);
+ if (ret)
+ goto err_disable_spiclk;
+
+ rs->dev = &pdev->dev;
+ rs->freq = clk_get_rate(rs->spiclk);
+
+ if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
+ &rsd_nsecs)) {
+ /* rx sample delay is expressed in parent clock cycles (max 3) */
+ u32 rsd = DIV_ROUND_CLOSEST(rsd_nsecs * (rs->freq >> 8),
+ 1000000000 >> 8);
+ if (!rsd) {
+ dev_warn(rs->dev, "%u Hz are too slow to express %u ns delay\n",
+ rs->freq, rsd_nsecs);
+ } else if (rsd > CR0_RSD_MAX) {
+ rsd = CR0_RSD_MAX;
+ dev_warn(rs->dev, "%u Hz are too fast to express %u ns delay, clamping at %u ns\n",
+ rs->freq, rsd_nsecs,
+ CR0_RSD_MAX * 1000000000U / rs->freq);
+ }
+ rs->rsd = rsd;
+ }
+
+ rs->fifo_len = get_fifo_len(rs);
+ if (!rs->fifo_len) {
+ dev_err(&pdev->dev, "Failed to get fifo length\n");
+ ret = -EINVAL;
+ goto err_disable_spiclk;
+ }
+
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
+ ctlr->auto_runtime_pm = true;
+ ctlr->bus_num = pdev->id;
+ ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_LSB_FIRST;
+ if (slave_mode) {
+ ctlr->mode_bits |= SPI_NO_CS;
+ ctlr->slave_abort = rockchip_spi_slave_abort;
+ } else {
+ ctlr->flags = SPI_MASTER_GPIO_SS;
+ ctlr->max_native_cs = ROCKCHIP_SPI_MAX_CS_NUM;
+ /*
+ * rk spi0 has two native cs, spi1..5 one cs only
+ * if num-cs is missing in the dts, default to 1
+ */
+ if (of_property_read_u32(np, "num-cs", &num_cs))
+ num_cs = 1;
+ ctlr->num_chipselect = num_cs;
+ ctlr->use_gpio_descriptors = true;
+ }
+ ctlr->dev.of_node = pdev->dev.of_node;
+ ctlr->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8) | SPI_BPW_MASK(4);
+ ctlr->min_speed_hz = rs->freq / BAUDR_SCKDV_MAX;
+ ctlr->max_speed_hz = min(rs->freq / BAUDR_SCKDV_MIN, MAX_SCLK_OUT);
+
+ ctlr->set_cs = rockchip_spi_set_cs;
+ ctlr->transfer_one = rockchip_spi_transfer_one;
+ ctlr->max_transfer_size = rockchip_spi_max_transfer_size;
+ ctlr->handle_err = rockchip_spi_handle_err;
+
+ ctlr->dma_tx = dma_request_chan(rs->dev, "tx");
+ if (IS_ERR(ctlr->dma_tx)) {
+ /* Check tx to see if we need defer probing driver */
+ if (PTR_ERR(ctlr->dma_tx) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto err_disable_pm_runtime;
+ }
+ dev_warn(rs->dev, "Failed to request TX DMA channel\n");
+ ctlr->dma_tx = NULL;
+ }
+
+ ctlr->dma_rx = dma_request_chan(rs->dev, "rx");
+ if (IS_ERR(ctlr->dma_rx)) {
+ if (PTR_ERR(ctlr->dma_rx) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto err_free_dma_tx;
+ }
+ dev_warn(rs->dev, "Failed to request RX DMA channel\n");
+ ctlr->dma_rx = NULL;
+ }
+
+ if (ctlr->dma_tx && ctlr->dma_rx) {
+ rs->dma_addr_tx = mem->start + ROCKCHIP_SPI_TXDR;
+ rs->dma_addr_rx = mem->start + ROCKCHIP_SPI_RXDR;
+ ctlr->can_dma = rockchip_spi_can_dma;
+ }
+
+ ret = devm_spi_register_controller(&pdev->dev, ctlr);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to register controller\n");
+ goto err_free_dma_rx;
+ }
+
+ return 0;
+
+err_free_dma_rx:
+ if (ctlr->dma_rx)
+ dma_release_channel(ctlr->dma_rx);
+err_free_dma_tx:
+ if (ctlr->dma_tx)
+ dma_release_channel(ctlr->dma_tx);
+err_disable_pm_runtime:
+ pm_runtime_disable(&pdev->dev);
+err_disable_spiclk:
+ clk_disable_unprepare(rs->spiclk);
+err_disable_apbclk:
+ clk_disable_unprepare(rs->apb_pclk);
+err_put_ctlr:
+ spi_controller_put(ctlr);
+
+ return ret;
+}
+
+static int rockchip_spi_remove(struct platform_device *pdev)
+{
+ struct spi_controller *ctlr = spi_controller_get(platform_get_drvdata(pdev));
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ pm_runtime_get_sync(&pdev->dev);
+
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+
+ if (ctlr->dma_tx)
+ dma_release_channel(ctlr->dma_tx);
+ if (ctlr->dma_rx)
+ dma_release_channel(ctlr->dma_rx);
+
+ spi_controller_put(ctlr);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int rockchip_spi_suspend(struct device *dev)
+{
+ int ret;
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+
+ ret = spi_controller_suspend(ctlr);
+ if (ret < 0)
+ return ret;
+
+ ret = pm_runtime_force_suspend(dev);
+ if (ret < 0)
+ return ret;
+
+ pinctrl_pm_select_sleep_state(dev);
+
+ return 0;
+}
+
+static int rockchip_spi_resume(struct device *dev)
+{
+ int ret;
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ pinctrl_pm_select_default_state(dev);
+
+ ret = pm_runtime_force_resume(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = spi_controller_resume(ctlr);
+ if (ret < 0) {
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+ }
+
+ return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int rockchip_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+
+ return 0;
+}
+
+static int rockchip_spi_runtime_resume(struct device *dev)
+{
+ int ret;
+ struct spi_controller *ctlr = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);
+
+ ret = clk_prepare_enable(rs->apb_pclk);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_prepare_enable(rs->spiclk);
+ if (ret < 0)
+ clk_disable_unprepare(rs->apb_pclk);
+
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops rockchip_spi_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
+ SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
+ rockchip_spi_runtime_resume, NULL)
+};
+
+static const struct of_device_id rockchip_spi_dt_match[] = {
+ { .compatible = "rockchip,px30-spi", },
+ { .compatible = "rockchip,rk3036-spi", },
+ { .compatible = "rockchip,rk3066-spi", },
+ { .compatible = "rockchip,rk3188-spi", },
+ { .compatible = "rockchip,rk3228-spi", },
+ { .compatible = "rockchip,rk3288-spi", },
+ { .compatible = "rockchip,rk3308-spi", },
+ { .compatible = "rockchip,rk3328-spi", },
+ { .compatible = "rockchip,rk3368-spi", },
+ { .compatible = "rockchip,rk3399-spi", },
+ { .compatible = "rockchip,rv1108-spi", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
+
+static struct platform_driver rockchip_spi_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .pm = &rockchip_spi_pm,
+ .of_match_table = of_match_ptr(rockchip_spi_dt_match),
+ },
+ .probe = rockchip_spi_probe,
+ .remove = rockchip_spi_remove,
+};
+
+module_platform_driver(rockchip_spi_driver);
+
+MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
+MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
+MODULE_LICENSE("GPL v2");