[PATCH v3 2/2] spi: add driver for Rockchip RK3xxx SoCs integrated SPI
Addy Ke
addy.ke at rock-chips.com
Mon Jul 7 18:53:17 PDT 2014
In order to facilitate understanding, rockchip SPI controller IP design
looks similar in its registers to designware. But IC implementation
is different from designware, So we need a dedicated driver for Rockchip
RK3XXX SoCs integrated SPI. The main differences:
- dma request line: rockchip SPI controller have two DMA request line
for tx and rx.
- Register offset:
RK3288 DW
SPI_CTRLR0 0x0000 0x0000
SPI_CTRLR1 0x0004 0x0004
SPI_SSIENR 0x0008 0x0008
SPI_MWCR NONE 0x000c
SPI_SER 0x000c 0x0010
SPI_BAUDR 0x0010 0x0014
SPI_TXFTLR 0x0014 0x0018
SPI_RXFTLR 0x0018 0x001c
SPI_TXFLR 0x001c 0x0020
SPI_RXFLR 0x0020 0x0024
SPI_SR 0x0024 0x0028
SPI_IPR 0x0028 NONE
SPI_IMR 0x002c 0x002c
SPI_ISR 0x0030 0x0030
SPI_RISR 0x0034 0x0034
SPI_TXOICR NONE 0x0038
SPI_RXOICR NONE 0x003c
SPI_RXUICR NONE 0x0040
SPI_MSTICR NONE 0x0044
SPI_ICR 0x0038 0x0048
SPI_DMACR 0x003c 0x004c
SPI_DMATDLR 0x0040 0x0050
SPI_DMARDLR 0x0044 0x0054
SPI_TXDR 0x0400 NONE
SPI_RXDR 0x0800 NONE
SPI_IDR NONE 0x0058
SPI_VERSION NONE 0x005c
SPI_DR NONE 0x0060
- register configuration:
RK3288 DW
- SPI_CTROL0:
control frame size bit[5:2] bit[15:12]
shift register loop NONE bit[11]
transfer mode bit[19:18] bit[9:8]
frame format bit[17:16] bit[5:4]
data frame size bit[1:0] bit[3:0]
For more information, see RK3288 chip manual.
- Wait for idle: Must ensure that the FIFO data has been sent out
before the next transfer.
Signed-off-by: Addy Ke <addy.ke at rock-chips.com>
---
changes since v1:
- more specific about the differences according to comments from Mark Brown
- not to cast away "const" according to comments from Mark Brown
- add set_cs() operation provided to the core
- change rockchip_spi_hw_init() to get_fifo_len()
- remove spi_setup() and spi_clean() operations
- remove wait_for_dma(), replaced by calling spi_finalize_current_transfer() when done
- remove wait_for_not_busy(), replaced by setting xfer->delay_usecs
- remove interrupt handler
- call clk_disable_unprepare() if spi_master_resume() failed
changes since v2:
- Kconfig: add "depends on (ARCH_ROCKCHIP || COMPILE_TEST)" for SPI_ROCKCHIP
- use wait_for_idle and do not set xfer->delay_uses suggested by Mark Brown
- master->mode_bits: remove SPI_CS_HIGH bit, according to comments from Jonas Gorski
- remove some log information suggested by Mark Brown
- remove Unneeded semicolon
- add compatible strings for RK3188 and RK3288
- improve differences between RK3288 and DW, provided by IC engineer.
- fixed some warning checked by "./scripts/checkpatch.pl --strict"
drivers/spi/Kconfig | 12 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-rockchip.c | 837 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 850 insertions(+)
create mode 100644 drivers/spi/spi-rockchip.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 60f2b41..c4e307b 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -375,6 +375,18 @@ config SPI_PXA2XX
config SPI_PXA2XX_PCI
def_tristate SPI_PXA2XX && PCI
+config SPI_ROCKCHIP
+ tristate "Rockchip SPI controller driver"
+ depends on (ARCH_ROCKCHIP || COMPILE_TEST)
+ help
+ This selects a driver for Rockchip SPI controller.
+
+ If you say yes to this option, support will be included for
+ RK3066, RK3188 and RK3288 families of SPI controller.
+ Rockchip SPI controller support DMA transport and PIO mode.
+ The main usecase of this controller is to use spi flash as boot
+ device.
+
config SPI_RSPI
tristate "Renesas RSPI/QSPI controller"
depends on (SUPERH && SH_DMAE_BASE) || ARCH_SHMOBILE
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index bd79266..361fbf3 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -60,6 +60,7 @@ spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o
obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o
obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o
obj-$(CONFIG_SPI_QUP) += spi-qup.o
+obj-$(CONFIG_SPI_ROCKCHIP) += spi-rockchip.o
obj-$(CONFIG_SPI_RSPI) += spi-rspi.o
obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o
spi-s3c24xx-hw-y := spi-s3c24xx.o
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
new file mode 100644
index 0000000..488a7b8
--- /dev/null
+++ b/drivers/spi/spi-rockchip.c
@@ -0,0 +1,837 @@
+/*
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ * Author: Addy Ke <addy.ke at rock-chips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/scatterlist.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+#include <linux/io.h>
+#include <linux/scatterlist.h>
+#include <linux/dmaengine.h>
+
+#define DRIVER_NAME "rockchip-spi"
+
+/* 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_TXDR 0x0400
+#define ROCKCHIP_SPI_RXDR 0x0800
+
+/* Bit fields in CTRLR0 */
+#define CR0_DFS_OFFSET 0
+
+#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_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 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)
+
+#define RXBUSY (1 << 0)
+#define TXBUSY (1 << 1)
+
+enum rockchip_ssi_type {
+ SSI_MOTO_SPI = 0,
+ SSI_TI_SSP,
+ SSI_NS_MICROWIRE,
+};
+
+struct rockchip_spi_dma_data {
+ struct dma_chan *ch;
+ enum dma_transfer_direction direction;
+ dma_addr_t addr;
+};
+
+struct rockchip_spi {
+ struct device *dev;
+ struct spi_master *master;
+
+ struct clk *spiclk;
+ struct clk *apb_pclk;
+
+ void __iomem *regs;
+ /*depth of the FIFO buffer */
+ u32 fifo_len;
+ /* max bus freq supported */
+ u32 max_freq;
+ /* supported slave numbers */
+ enum rockchip_ssi_type type;
+
+ u16 mode;
+ u8 tmode;
+ u8 bpw;
+ u8 n_bytes;
+ unsigned len;
+ u32 speed;
+
+ const void *tx;
+ const void *tx_end;
+ void *rx;
+ void *rx_end;
+
+ u32 state;
+ /* protect state */
+ spinlock_t lock;
+
+ struct completion xfer_completion;
+
+ u32 use_dma;
+ struct sg_table tx_sg;
+ struct sg_table rx_sg;
+ struct rockchip_spi_dma_data dma_rx;
+ struct rockchip_spi_dma_data dma_tx;
+};
+
+static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
+{
+ writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
+}
+
+static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
+{
+ writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
+}
+
+static inline void flush_fifo(struct rockchip_spi *rs)
+{
+ while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR))
+ readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
+}
+
+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_before(jiffies, timeout));
+
+ dev_warn(rs->dev, "spi controller is in busy state!\n");
+}
+
+static u32 get_fifo_len(struct rockchip_spi *rs)
+{
+ u32 fifo;
+
+ for (fifo = 2; fifo < 32; fifo++) {
+ writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
+ if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
+ break;
+ }
+ writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
+
+ return (fifo == 31) ? 0 : fifo;
+}
+
+static inline u32 tx_max(struct rockchip_spi *rs)
+{
+ u32 tx_left, tx_room;
+
+ tx_left = (rs->tx_end - rs->tx) / rs->n_bytes;
+ tx_room = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
+
+ return min(tx_left, tx_room);
+}
+
+static inline u32 rx_max(struct rockchip_spi *rs)
+{
+ u32 rx_left = (rs->rx_end - rs->rx) / rs->n_bytes;
+ u32 rx_room = (u32)readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
+
+ return min(rx_left, rx_room);
+}
+
+static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ u32 ser;
+ struct rockchip_spi *rs = spi_master_get_devdata(spi->master);
+
+ ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK;
+
+ /*
+ * drivers/spi/spi.c:
+ * static void spi_set_cs(struct spi_device *spi, bool enable)
+ * {
+ * if (spi->mode & SPI_CS_HIGH)
+ * enable = !enable;
+ *
+ * if (spi->cs_gpio >= 0)
+ * gpio_set_value(spi->cs_gpio, !enable);
+ * else if (spi->master->set_cs)
+ * spi->master->set_cs(spi, !enable);
+ * }
+ *
+ * Note: enable(rockchip_spi_set_cs) = !enable(spi_set_cs)
+ */
+ if (!enable)
+ ser |= 1 << spi->chip_select;
+ else
+ ser &= ~(1 << spi->chip_select);
+
+ writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER);
+}
+
+static int rockchip_spi_prepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+ struct spi_device *spi = msg->spi;
+
+ rs->mode = spi->mode;
+
+ return 0;
+}
+
+static int rockchip_spi_unprepare_message(struct spi_master *master,
+ struct spi_message *msg)
+{
+ unsigned long flags;
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ spin_lock_irqsave(&rs->lock, flags);
+
+ /*
+ * For DMA mode, we need terminate DMA channel and flush
+ * fifo for the next transfer if DMA thansfer timeout.
+ * unprepare_message() was called by core if transfer complete
+ * or timeout. Maybe it is reasonable for error handling here.
+ */
+ if (rs->use_dma) {
+ if (rs->state & RXBUSY) {
+ dmaengine_terminate_all(rs->dma_rx.ch);
+ flush_fifo(rs);
+ }
+
+ if (rs->state & TXBUSY)
+ dmaengine_terminate_all(rs->dma_tx.ch);
+ }
+
+ spin_unlock_irqrestore(&rs->lock, flags);
+
+ return 0;
+}
+
+static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
+{
+ u32 max = tx_max(rs);
+ u32 txw = 0;
+
+ while (max--) {
+ 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 max = rx_max(rs);
+ u32 rxw;
+
+ while (max--) {
+ rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
+ if (rs->n_bytes == 1)
+ *(u8 *)(rs->rx) = (u8)rxw;
+ else
+ *(u16 *)(rs->rx) = (u16)rxw;
+ rs->rx += rs->n_bytes;
+ }
+}
+
+static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
+{
+ int remain = 0;
+
+ do {
+ if (rs->tx) {
+ remain = rs->tx_end - rs->tx;
+ rockchip_spi_pio_writer(rs);
+ }
+
+ if (rs->rx) {
+ remain = rs->rx_end - rs->rx;
+ rockchip_spi_pio_reader(rs);
+ }
+
+ cpu_relax();
+ } while (remain);
+
+ /* If tx, wait until the FIFO data completely. */
+ if (rs->tx)
+ wait_for_idle(rs);
+
+ return 0;
+}
+
+static void rockchip_spi_dma_rxcb(void *data)
+{
+ unsigned long flags;
+ struct rockchip_spi *rs = data;
+
+ spin_lock_irqsave(&rs->lock, flags);
+
+ rs->state &= ~RXBUSY;
+ if (!(rs->state & TXBUSY))
+ spi_finalize_current_transfer(rs->master);
+
+ spin_unlock_irqrestore(&rs->lock, flags);
+}
+
+static void rockchip_spi_dma_txcb(void *data)
+{
+ unsigned long flags;
+ struct rockchip_spi *rs = data;
+
+ /* Wait until the FIFO data completely. */
+ wait_for_idle(rs);
+
+ spin_lock_irqsave(&rs->lock, flags);
+
+ rs->state &= ~TXBUSY;
+ if (!(rs->state & RXBUSY))
+ spi_finalize_current_transfer(rs->master);
+
+ spin_unlock_irqrestore(&rs->lock, flags);
+}
+
+static int rockchip_spi_dma_transfer(struct rockchip_spi *rs)
+{
+ unsigned long flags;
+ struct dma_slave_config rxconf, txconf;
+ struct dma_async_tx_descriptor *rxdesc, *txdesc;
+
+ spin_lock_irqsave(&rs->lock, flags);
+ rs->state &= ~RXBUSY;
+ rs->state &= ~TXBUSY;
+ spin_unlock_irqrestore(&rs->lock, flags);
+
+ if (rs->rx) {
+ rxconf.direction = rs->dma_rx.direction;
+ rxconf.src_addr = rs->dma_rx.addr;
+ rxconf.src_addr_width = rs->n_bytes;
+ rxconf.src_maxburst = rs->n_bytes;
+ dmaengine_slave_config(rs->dma_rx.ch, &rxconf);
+
+ rxdesc = dmaengine_prep_slave_sg(
+ rs->dma_rx.ch,
+ rs->rx_sg.sgl, rs->rx_sg.nents,
+ rs->dma_rx.direction, DMA_PREP_INTERRUPT);
+
+ rxdesc->callback = rockchip_spi_dma_rxcb;
+ rxdesc->callback_param = rs;
+ }
+
+ if (rs->tx) {
+ txconf.direction = rs->dma_tx.direction;
+ txconf.dst_addr = rs->dma_tx.addr;
+ txconf.dst_addr_width = rs->n_bytes;
+ txconf.dst_maxburst = rs->n_bytes;
+ dmaengine_slave_config(rs->dma_tx.ch, &txconf);
+
+ txdesc = dmaengine_prep_slave_sg(
+ rs->dma_tx.ch,
+ rs->tx_sg.sgl, rs->tx_sg.nents,
+ rs->dma_tx.direction, DMA_PREP_INTERRUPT);
+
+ txdesc->callback = rockchip_spi_dma_txcb;
+ txdesc->callback_param = rs;
+ }
+
+ /* rx must be started before tx due to spi instinct */
+ if (rs->rx) {
+ spin_lock_irqsave(&rs->lock, flags);
+ rs->state |= RXBUSY;
+ spin_unlock_irqrestore(&rs->lock, flags);
+ dmaengine_submit(rxdesc);
+ dma_async_issue_pending(rs->dma_rx.ch);
+ }
+
+ if (rs->tx) {
+ spin_lock_irqsave(&rs->lock, flags);
+ rs->state |= TXBUSY;
+ spin_unlock_irqrestore(&rs->lock, flags);
+ dmaengine_submit(txdesc);
+ dma_async_issue_pending(rs->dma_tx.ch);
+ }
+
+ return 1;
+}
+
+static void rockchip_spi_config(struct rockchip_spi *rs)
+{
+ u32 div = 0;
+ u32 dmacr = 0;
+
+ u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET)
+ | (CR0_SSD_ONE << CR0_SSD_OFFSET);
+
+ cr0 |= (rs->n_bytes << CR0_DFS_OFFSET);
+ cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET);
+ cr0 |= (rs->tmode << CR0_XFM_OFFSET);
+ cr0 |= (rs->type << CR0_FRF_OFFSET);
+
+ if (rs->use_dma) {
+ if (rs->tx)
+ dmacr |= TF_DMA_EN;
+ if (rs->rx)
+ dmacr |= RF_DMA_EN;
+ }
+
+ /* div doesn't support odd number */
+ div = rs->max_freq / rs->speed;
+ div = (div + 1) & 0xfffe;
+
+ spi_enable_chip(rs, 0);
+
+ writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
+
+ writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
+ writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR);
+ writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
+
+ writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR);
+ writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
+ writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
+
+ spi_set_clk(rs, div);
+
+ dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div);
+
+ spi_enable_chip(rs, 1);
+}
+
+static int rockchip_spi_transfer_one(
+ struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ int ret = 0;
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ WARN_ON((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;
+ }
+
+ rs->speed = xfer->speed_hz;
+ rs->bpw = xfer->bits_per_word;
+ rs->n_bytes = rs->bpw >> 3;
+
+ rs->tx = xfer->tx_buf;
+ rs->tx_end = rs->tx + xfer->len;
+ rs->rx = xfer->rx_buf;
+ rs->rx_end = rs->rx + xfer->len;
+ rs->len = xfer->len;
+
+ rs->tx_sg = xfer->tx_sg;
+ rs->rx_sg = xfer->rx_sg;
+
+ if (rs->tx && rs->rx)
+ rs->tmode = CR0_XFM_TR;
+ else if (rs->tx)
+ rs->tmode = CR0_XFM_TO;
+ else if (rs->rx)
+ rs->tmode = CR0_XFM_RO;
+
+ if (master->can_dma && master->can_dma(master, spi, xfer))
+ rs->use_dma = 1;
+ else
+ rs->use_dma = 0;
+
+ rockchip_spi_config(rs);
+
+ if (rs->use_dma)
+ ret = rockchip_spi_dma_transfer(rs);
+ else
+ ret = rockchip_spi_pio_transfer(rs);
+
+ return ret;
+}
+
+static bool rockchip_spi_can_dma(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *xfer)
+{
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ return (xfer->len > rs->fifo_len);
+}
+
+static int rockchip_spi_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct rockchip_spi *rs;
+ struct spi_master *master;
+ struct resource *mem;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
+ if (!master)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, master);
+
+ rs = spi_master_get_devdata(master);
+ memset(rs, 0, sizeof(struct rockchip_spi));
+
+ /* 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)) {
+ dev_err(&pdev->dev, "Failed to map SPI region\n");
+ ret = PTR_ERR(rs->regs);
+ goto err_ioremap_resource;
+ }
+
+ 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_ioremap_resource;
+ }
+
+ 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_ioremap_resource;
+ }
+
+ ret = clk_prepare_enable(rs->apb_pclk);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
+ goto err_ioremap_resource;
+ }
+
+ ret = clk_prepare_enable(rs->spiclk);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to enable spi_clk\n");
+ goto err_spiclk_enable;
+ }
+
+ spi_enable_chip(rs, 0);
+
+ rs->type = SSI_MOTO_SPI;
+ rs->master = master;
+ rs->dev = &pdev->dev;
+ rs->max_freq = clk_get_rate(rs->spiclk);
+
+ rs->fifo_len = get_fifo_len(rs);
+ if (!rs->fifo_len) {
+ dev_err(&pdev->dev, "Failed to get fifo length\n");
+ goto err_get_fifo_len;
+ }
+
+ spin_lock_init(&rs->lock);
+
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
+ master->auto_runtime_pm = true;
+ master->bus_num = pdev->id;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
+ master->num_chipselect = 2;
+ master->dev.of_node = pdev->dev.of_node;
+ master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
+
+ master->set_cs = rockchip_spi_set_cs;
+ master->prepare_message = rockchip_spi_prepare_message;
+ master->unprepare_message = rockchip_spi_unprepare_message;
+ master->transfer_one = rockchip_spi_transfer_one;
+
+ rs->dma_tx.ch = dma_request_slave_channel(rs->dev, "tx");
+ if (!rs->dma_tx.ch)
+ dev_warn(rs->dev, "Failed to request TX DMA channel\n");
+
+ rs->dma_rx.ch = dma_request_slave_channel(rs->dev, "rx");
+ if (!rs->dma_rx.ch) {
+ if (rs->dma_tx.ch) {
+ dma_release_channel(rs->dma_tx.ch);
+ rs->dma_tx.ch = NULL;
+ }
+ dev_warn(rs->dev, "Failed to request RX DMA channel\n");
+ }
+
+ if (rs->dma_tx.ch && rs->dma_rx.ch) {
+ rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
+ rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
+ rs->dma_tx.direction = DMA_MEM_TO_DEV;
+ rs->dma_tx.direction = DMA_DEV_TO_MEM;
+
+ master->can_dma = rockchip_spi_can_dma;
+ master->dma_tx = rs->dma_tx.ch;
+ master->dma_rx = rs->dma_rx.ch;
+ }
+
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to register master\n");
+ goto err_register_master;
+ }
+
+ return 0;
+
+err_register_master:
+ if (rs->dma_tx.ch)
+ dma_release_channel(rs->dma_tx.ch);
+ if (rs->dma_rx.ch)
+ dma_release_channel(rs->dma_rx.ch);
+err_get_fifo_len:
+ clk_disable_unprepare(rs->spiclk);
+err_spiclk_enable:
+ clk_disable_unprepare(rs->apb_pclk);
+err_ioremap_resource:
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int rockchip_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ pm_runtime_disable(&pdev->dev);
+
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+
+ if (rs->dma_tx.ch)
+ dma_release_channel(rs->dma_tx.ch);
+ if (rs->dma_rx.ch)
+ dma_release_channel(rs->dma_rx.ch);
+
+ spi_master_put(master);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int rockchip_spi_suspend(struct device *dev)
+{
+ int ret = 0;
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ ret = spi_master_suspend(rs->master);
+ if (ret)
+ return ret;
+
+ if (!pm_runtime_suspended(dev)) {
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+ }
+
+ return ret;
+}
+
+static int rockchip_spi_resume(struct device *dev)
+{
+ int ret = 0;
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ if (!pm_runtime_suspended(dev)) {
+ 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 ret;
+ }
+ }
+
+ ret = spi_master_resume(rs->master);
+ if (ret < 0) {
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);
+ }
+
+ return ret;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_RUNTIME
+static int rockchip_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ 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_master *master = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+ ret = clk_prepare_enable(rs->apb_pclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(rs->spiclk);
+ if (ret)
+ clk_disable_unprepare(rs->apb_pclk);
+
+ return ret;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
+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,rk3066-spi", },
+ { .compatible = "rockchip,rk3188-spi", },
+ { .compatible = "rockchip,rk3288-spi", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
+
+static struct platform_driver rockchip_spi_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .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 at rock-chips.com>");
+MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
+MODULE_LICENSE("GPL v2");
--
1.8.3.2
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