lkml.org 
[lkml]   [2014]   [Jun]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 2/2] spi: add driver for Rockchip RK3xxx SoCs integrated SPI
Date
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:
such as SPI_CTRLRO in rockchip SPI controller:
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);
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@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

drivers/spi/Kconfig | 11 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-rockchip.c | 822 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 834 insertions(+)
create mode 100644 drivers/spi/spi-rockchip.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 60f2b41..5b51ab2 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -375,6 +375,17 @@ config SPI_PXA2XX
config SPI_PXA2XX_PCI
def_tristate SPI_PXA2XX && PCI

+config SPI_ROCKCHIP
+ tristate "Rockchip SPI controller driver"
+ 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..72fb287
--- /dev/null
+++ b/drivers/spi/spi-rockchip.c
@@ -0,0 +1,822 @@
+/*
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ * Author: addy ke <addy.ke@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;
+
+ 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 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;
+
+ if (spi->mode & SPI_CS_HIGH) {
+ dev_err(rs->dev, "spi_cs_hign: not support\n");
+ return -EINVAL;
+ }
+
+ 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);
+
+ 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);
+
+ 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;
+
+ 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;
+
+ /* Delay until the FIFO data completely */
+ if (xfer->tx_buf)
+ xfer->delay_usecs
+ = rs->fifo_len * rs->bpw * 1000000 / rs->speed;
+
+ 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) {
+ dev_err(&pdev->dev, "No memory for spi_master\n");
+ 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_CS_HIGH | 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;
+ }
+
+ dev_info(&pdev->dev, "Rockchip SPI controller initialized\n");
+
+ 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", },
+ { },
+};
+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@rock-chips.com>");
+MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
+MODULE_LICENSE("GPL v2");
--
1.8.3.2



\
 
 \ /
  Last update: 2014-07-01 03:21    [W:0.186 / U:27.336 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site