From: Lanqing Liu <lanqing.liu@xxxxxxxxxxxxxx>
This patch adds the SPI controller driver for Spreadtrum SC9860 platform.
Signed-off-by: Lanqing Liu <lanqing.liu@xxxxxxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
Changes from v1:
- Enable the auto_runtime_pm of SPI core.
- Remove the sprd_spi_setup() function.
- Move the hardware SPI hardware initialization to transfer setup function.
- Modify the SPI speed calculation formula.
- Add one hw_speed_hz field to save the real SPI line speed.
- Optimize the method of the spi_max_speed variable initialization.
- Optimize the word delay time.
- Fix some coding style issues.
---
drivers/spi/Kconfig | 6 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-sprd.c | 745 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 752 insertions(+)
create mode 100644 drivers/spi/spi-sprd.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ad5d68e..c49c40c 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -596,6 +596,12 @@ config SPI_SIRF
help
SPI driver for CSR SiRFprimaII SoCs
+config SPI_SPRD
+ tristate "Spreadtrum SPI controller"
+ depends on ARCH_SPRD || COMPILE_TEST
+ help
+ SPI driver for Spreadtrum SoCs.
+
config SPI_SPRD_ADI
tristate "Spreadtrum ADI controller"
depends on ARCH_SPRD || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index cb1f437..5bb6b37 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_SPI_SH_HSPI) += spi-sh-hspi.o
obj-$(CONFIG_SPI_SH_MSIOF) += spi-sh-msiof.o
obj-$(CONFIG_SPI_SH_SCI) += spi-sh-sci.o
obj-$(CONFIG_SPI_SIRF) += spi-sirf.o
+obj-$(CONFIG_SPI_SPRD) += spi-sprd.o
obj-$(CONFIG_SPI_SPRD_ADI) += spi-sprd-adi.o
obj-$(CONFIG_SPI_STM32) += spi-stm32.o
obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o
diff --git a/drivers/spi/spi-sprd.c b/drivers/spi/spi-sprd.c
new file mode 100644
index 0000000..a9a6c5e
--- /dev/null
+++ b/drivers/spi/spi-sprd.c
@@ -0,0 +1,745 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+
+#define SPRD_SPI_TXD 0x0
+#define SPRD_SPI_CLKD 0x4
+#define SPRD_SPI_CTL0 0x8
+#define SPRD_SPI_CTL1 0xc
+#define SPRD_SPI_CTL2 0x10
+#define SPRD_SPI_CTL3 0x14
+#define SPRD_SPI_CTL4 0x18
+#define SPRD_SPI_CTL5 0x1c
+#define SPRD_SPI_INT_EN 0x20
+#define SPRD_SPI_INT_CLR 0x24
+#define SPRD_SPI_INT_RAW_STS 0x28
+#define SPRD_SPI_INT_MASK_STS 0x2c
+#define SPRD_SPI_STS1 0x30
+#define SPRD_SPI_STS2 0x34
+#define SPRD_SPI_DSP_WAIT 0x38
+#define SPRD_SPI_STS3 0x3c
+#define SPRD_SPI_CTL6 0x40
+#define SPRD_SPI_STS4 0x44
+#define SPRD_SPI_FIFO_RST 0x48
+#define SPRD_SPI_CTL7 0x4c
+#define SPRD_SPI_STS5 0x50
+#define SPRD_SPI_CTL8 0x54
+#define SPRD_SPI_CTL9 0x58
+#define SPRD_SPI_CTL10 0x5c
+#define SPRD_SPI_CTL11 0x60
+#define SPRD_SPI_CTL12 0x64
+#define SPRD_SPI_STS6 0x68
+#define SPRD_SPI_STS7 0x6c
+#define SPRD_SPI_STS8 0x70
+#define SPRD_SPI_STS9 0x74
+
+/* Bits & mask definition for register CTL0 */
+#define SPRD_SPI_SCK_REV BIT(13)
+#define SPRD_SPI_NG_TX BIT(1)
+#define SPRD_SPI_NG_RX BIT(0)
+#define SPRD_SPI_CHNL_LEN_MASK GENMASK(4, 0)
+#define SPRD_SPI_CSN_MASK GENMASK(11, 8)
+#define SPRD_SPI_CS0_VALID BIT(8)
+
+/* Bits & mask definition for register SPI_INT_EN */
+#define SPRD_SPI_TX_END_INT_EN BIT(8)
+#define SPRD_SPI_RX_END_INT_EN BIT(9)
+
+/* Bits & mask definition for register SPI_INT_RAW_STS */
+#define SPRD_SPI_TX_END_RAW BIT(8)
+#define SPRD_SPI_RX_END_RAW BIT(9)
+
+/* Bits & mask definition for register SPI_INT_CLR */
+#define SPRD_SPI_TX_END_CLR BIT(8)
+#define SPRD_SPI_RX_END_CLR BIT(9)
+
+/* Bits & mask definition for register INT_MASK_STS */
+#define SPRD_SPI_MASK_RX_END BIT(9)
+#define SPRD_SPI_MASK_TX_END BIT(8)
+
+/* Bits & mask definition for register STS2 */
+#define SPRD_SPI_TX_BUSY BIT(8)
+
+/* Bits & mask definition for register CTL1 */
+#define SPRD_SPI_RX_MODE BIT(12)
+#define SPRD_SPI_TX_MODE BIT(13)
+#define SPRD_SPI_RTX_MD_MASK GENMASK(13, 12)
+
+/* Bits & mask definition for register CTL2 */
+#define SPRD_SPI_DMA_EN BIT(6)
+
+/* Bits & mask definition for register CTL4 */
+#define SPRD_SPI_START_RX BIT(9)
+#define SPRD_SPI_ONLY_RECV_MASK GENMASK(8, 0)
+
+/* Bits & mask definition for register SPI_INT_CLR */
+#define SPRD_SPI_RX_END_INT_CLR BIT(9)
+#define SPRD_SPI_TX_END_INT_CLR BIT(8)
+
+/* Bits & mask definition for register SPI_INT_RAW */
+#define SPRD_SPI_RX_END_IRQ BIT(9)
+#define SPRD_SPI_TX_END_IRQ BIT(8)
+
+/* Bits & mask definition for register CTL12 */
+#define SPRD_SPI_SW_RX_REQ BIT(0)
+#define SPRD_SPI_SW_TX_REQ BIT(1)
+
+/* Bits & mask definition for register CTL7 */
+#define SPRD_SPI_DATA_LINE2_EN BIT(15)
+#define SPRD_SPI_MODE_MASK GENMASK(5, 3)
+#define SPRD_SPI_MODE_OFFSET 3
+#define SPRD_SPI_3WIRE_MODE 4
+#define SPRD_SPI_4WIRE_MODE 0
+
+/* Bits & mask definition for register CTL8 */
+#define SPRD_SPI_TX_MAX_LEN_MASK GENMASK(19, 0)
+#define SPRD_SPI_TX_LEN_H_MASK GENMASK(3, 0)
+#define SPRD_SPI_TX_LEN_H_OFFSET 16
+
+/* Bits & mask definition for register CTL9 */
+#define SPRD_SPI_TX_LEN_L_MASK GENMASK(15, 0)
+
+/* Bits & mask definition for register CTL10 */
+#define SPRD_SPI_RX_MAX_LEN_MASK GENMASK(19, 0)
+#define SPRD_SPI_RX_LEN_H_MASK GENMASK(3, 0)
+#define SPRD_SPI_RX_LEN_H_OFFSET 16
+
+/* Bits & mask definition for register CTL11 */
+#define SPRD_SPI_RX_LEN_L_MASK GENMASK(15, 0)
+
+/* Default & maximum word delay cycles */
+#define SPRD_SPI_MIN_DELAY_CYCLE 14
+#define SPRD_SPI_MAX_DELAY_CYCLE 130
+
+#define SPRD_SPI_FIFO_SIZE 32
+#define SPRD_SPI_CHIP_CS_NUM 0x4
+#define SPRD_SPI_CHNL_LEN 2
+#define SPRD_SPI_DEFAULT_SOURCE 26000000
+#define SPRD_SPI_MAX_SPEED_HZ 48000000
+#define SPRD_SPI_AUTOSUSPEND_DELAY 100
+
+struct sprd_spi {
+ void __iomem *base;
+ struct device *dev;
+ struct clk *clk;
+ u32 src_clk;
+ u32 hw_mode;
+ u32 trans_len;
+ u32 trans_mode;
+ u32 word_delay;
+ u32 hw_speed_hz;
+ u32 len;
+ int status;
+ const void *tx_buf;
+ void *rx_buf;
+ int (*read_bufs)(struct sprd_spi *ss, u32 len);
+ int (*write_bufs)(struct sprd_spi *ss, u32 len);
+};
+
+static u32 sprd_spi_transfer_max_timeout(struct sprd_spi *ss,
+ struct spi_transfer *t)
+{
+ /*
+ * The time spent on transmission of the full FIFO data is the maximum
+ * SPI transmission time.
+ */
+ u32 size = t->bits_per_word * SPRD_SPI_FIFO_SIZE;
+ u32 bit_time_us = DIV_ROUND_UP(USEC_PER_SEC, ss->hw_speed_hz);
+ u32 total_time_us = size * bit_time_us;
+ /*
+ * There is an interval between data and the data in our SPI hardware,
+ * so the total transmission time need add the interval time.
+ */
+ u32 interval_cycle = SPRD_SPI_FIFO_SIZE * ss->word_delay;
+ u32 interval_time_us = DIV_ROUND_UP(interval_cycle * USEC_PER_SEC,
+ ss->src_clk);
+
+ return total_time_us + interval_time_us;
+}
+
+static int sprd_spi_wait_for_tx_end(struct sprd_spi *ss, struct spi_transfer *t)
+{
+ u32 val, us;
+ int ret;
+
+ us = sprd_spi_transfer_max_timeout(ss, t);
+ ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val,
+ val & SPRD_SPI_TX_END_IRQ, 0, us);
+ if (ret) {
+ dev_err(ss->dev, "SPI error, spi send timeout!\n");
+ return ret;
+ }
+
+ ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_STS2, val,
+ !(val & SPRD_SPI_TX_BUSY), 0, us);
+ if (ret) {
+ dev_err(ss->dev, "SPI error, spi busy timeout!\n");
+ return ret;
+ }
+
+ writel_relaxed(SPRD_SPI_TX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR);
+
+ return 0;
+}
+
+static int sprd_spi_wait_for_rx_end(struct sprd_spi *ss, struct spi_transfer *t)
+{
+ u32 val, us;
+ int ret;
+
+ us = sprd_spi_transfer_max_timeout(ss, t);
+ ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val,
+ val & SPRD_SPI_RX_END_IRQ, 0, us);
+ if (ret) {
+ dev_err(ss->dev, "SPI error, spi rx timeout!\n");
+ return ret;
+ }
+
+ writel_relaxed(SPRD_SPI_RX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR);
+
+ return 0;
+}
+
+static void sprd_spi_tx_req(struct sprd_spi *ss)
+{
+ writel_relaxed(SPRD_SPI_SW_TX_REQ, ss->base + SPRD_SPI_CTL12);
+}
+
+static void sprd_spi_rx_req(struct sprd_spi *ss)
+{
+ writel_relaxed(SPRD_SPI_SW_RX_REQ, ss->base + SPRD_SPI_CTL12);
+}
+
+static void sprd_spi_enter_idle(struct sprd_spi *ss)
+{
+ u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL1);
+
+ val &= ~SPRD_SPI_RTX_MD_MASK;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL1);
+}
+
+static void sprd_spi_set_transfer_bits(struct sprd_spi *ss, u32 bits)
+{
+ u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL0);
+
+ /* Set the valid bits for every transaction */
+ val &= ~(SPRD_SPI_CHNL_LEN_MASK << SPRD_SPI_CHNL_LEN);
+ val |= bits << SPRD_SPI_CHNL_LEN;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
+}
+
+static void sprd_spi_set_tx_length(struct sprd_spi *ss, u32 length)
+{
+ u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL8);
+
+ length &= SPRD_SPI_TX_MAX_LEN_MASK;
+ val &= ~SPRD_SPI_TX_LEN_H_MASK;
+ val |= length >> SPRD_SPI_TX_LEN_H_OFFSET;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL8);
+
+ val = length & SPRD_SPI_TX_LEN_L_MASK;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL9);
+}
+
+static void sprd_spi_set_rx_length(struct sprd_spi *ss, u32 length)
+{
+ u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL10);
+
+ length &= SPRD_SPI_RX_MAX_LEN_MASK;
+ val &= ~SPRD_SPI_RX_LEN_H_MASK;
+ val |= length >> SPRD_SPI_RX_LEN_H_OFFSET;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL10);
+
+ val = length & SPRD_SPI_RX_LEN_L_MASK;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL11);
+}
+
+static void sprd_spi_chipselect(struct spi_device *sdev, bool cs)
+{
+ struct spi_controller *sctlr = sdev->controller;
+ struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
+ u32 val;
+
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL0);
+ /* The SPI controller will pull down CS pin if cs is 0 */
+ if (!cs) {
+ val &= ~SPRD_SPI_CS0_VALID;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
+ } else {
+ val |= SPRD_SPI_CSN_MASK;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
+ }
+}
+
+static int sprd_spi_write_only_receive(struct sprd_spi *ss, u32 len)
+{
+ u32 val;
+
+ /* Clear the start receive bit and reset receive data number */
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
+ val &= ~(SPRD_SPI_START_RX | SPRD_SPI_ONLY_RECV_MASK);
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
+
+ /* Set the receive data length */
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
+ val |= len & SPRD_SPI_ONLY_RECV_MASK;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
+
+ /* Trigger to receive data */
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
+ val |= SPRD_SPI_START_RX;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
+
+ return len;
+}
+
+static int sprd_spi_write_bufs_u8(struct sprd_spi *ss, u32 len)
+{
+ u8 *tx_p = (u8 *)ss->tx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ writeb_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
+
+ ss->tx_buf += i;
+ return i;
+}
+
+static int sprd_spi_write_bufs_u16(struct sprd_spi *ss, u32 len)
+{
+ u16 *tx_p = (u16 *)ss->tx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ writew_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
+
+ ss->tx_buf += i << 1;
+ return i << 1;
+}
+
+static int sprd_spi_write_bufs_u32(struct sprd_spi *ss, u32 len)
+{
+ u32 *tx_p = (u32 *)ss->tx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ writel_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
+
+ ss->tx_buf += i << 2;
+ return i << 2;
+}
+
+static int sprd_spi_read_bufs_u8(struct sprd_spi *ss, u32 len)
+{
+ u8 *rx_p = (u8 *)ss->rx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ rx_p[i] = readb_relaxed(ss->base + SPRD_SPI_TXD);
+
+ ss->rx_buf += i;
+ return i;
+}
+
+static int sprd_spi_read_bufs_u16(struct sprd_spi *ss, u32 len)
+{
+ u16 *rx_p = (u16 *)ss->rx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ rx_p[i] = readw_relaxed(ss->base + SPRD_SPI_TXD);
+
+ ss->rx_buf += i << 1;
+ return i << 1;
+}
+
+static int sprd_spi_read_bufs_u32(struct sprd_spi *ss, u32 len)
+{
+ u32 *rx_p = (u32 *)ss->rx_buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ rx_p[i] = readl_relaxed(ss->base + SPRD_SPI_TXD);
+
+ ss->rx_buf += i << 2;
+ return i << 2;
+}
+
+static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t)
+{
+ struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller);
+ u32 trans_len = ss->trans_len, len;
+ int ret, write_size = 0;
+
+ while (trans_len) {
+ len = trans_len > SPRD_SPI_FIFO_SIZE ? SPRD_SPI_FIFO_SIZE :
+ trans_len;
+ if (ss->trans_mode & SPRD_SPI_TX_MODE) {
+ sprd_spi_set_tx_length(ss, len);
+ write_size += ss->write_bufs(ss, len);
+
+ /*
+ * For our 3 wires mode or dual TX line mode, we need
+ * to request the controller to transfer.
+ */
+ if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
+ sprd_spi_tx_req(ss);
+
+ ret = sprd_spi_wait_for_tx_end(ss, t);
+ } else {
+ sprd_spi_set_rx_length(ss, len);
+
+ /*
+ * For our 3 wires mode or dual TX line mode, we need
+ * to request the controller to read.
+ */
+ if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
+ sprd_spi_rx_req(ss);
+ else
+ write_size += ss->write_bufs(ss, len);
+
+ ret = sprd_spi_wait_for_rx_end(ss, t);
+ }
+
+ if (ret)
+ goto complete;
+
+ if (ss->trans_mode & SPRD_SPI_RX_MODE)
+ ss->read_bufs(ss, len);
+
+ trans_len -= len;
+ }
+
+ ret = write_size;
+
+complete:
+ sprd_spi_enter_idle(ss);
+
+ return ret;
+}
+
+static void sprd_spi_set_speed(struct sprd_spi *ss, u32 speed_hz)
+{
+ /*
+ * From SPI datasheet, the prescale calculation formula:
+ * prescale = SPI source clock / (2 * SPI_freq) - 1;
+ */
+ u32 clk_div = DIV_ROUND_UP(ss->src_clk, speed_hz << 1) - 1;
+
+ /* Save the real hardware speed */
+ ss->hw_speed_hz = (ss->src_clk >> 1) / (clk_div + 1);
+ writel_relaxed(clk_div, ss->base + SPRD_SPI_CLKD);
+}
+
+static void sprd_spi_init_hw(struct sprd_spi *ss, struct spi_transfer *t)
+{
+ u16 word_delay, interval;
+ u32 val;
+
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL7);
+ val &= ~(SPRD_SPI_SCK_REV | SPRD_SPI_NG_TX | SPRD_SPI_NG_RX);
+ /* Set default chip selection, clock phase and clock polarity */
+ val |= ss->hw_mode & SPI_CPHA ? SPRD_SPI_NG_RX : SPRD_SPI_NG_TX;
+ val |= ss->hw_mode & SPI_CPOL ? SPRD_SPI_SCK_REV : 0;
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
+
+ /*
+ * Set the intervals of two SPI frames, and the inteval calculation
+ * formula as below per datasheet:
+ * interval time (source clock cycles) = interval * 4 + 10.
+ */
+ word_delay = clamp_t(u16, t->word_delay, SPRD_SPI_MIN_DELAY_CYCLE,
+ SPRD_SPI_MAX_DELAY_CYCLE);
+ interval = DIV_ROUND_UP(word_delay - 10, 4);
+ ss->word_delay = interval * 4 + 10;
+ writel_relaxed(interval, ss->base + SPRD_SPI_CTL5);
+
+ /* Reset SPI fifo */
+ writel_relaxed(1, ss->base + SPRD_SPI_FIFO_RST);
+ writel_relaxed(0, ss->base + SPRD_SPI_FIFO_RST);
+
+ /* Set SPI work mode */
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL7);
+ val &= ~SPRD_SPI_MODE_MASK;
+
+ if (ss->hw_mode & SPI_3WIRE)
+ val |= SPRD_SPI_3WIRE_MODE << SPRD_SPI_MODE_OFFSET;
+ else
+ val |= SPRD_SPI_4WIRE_MODE << SPRD_SPI_MODE_OFFSET;
+
+ if (ss->hw_mode & SPI_TX_DUAL)
+ val |= SPRD_SPI_DATA_LINE2_EN;
+ else
+ val &= ~SPRD_SPI_DATA_LINE2_EN;
+
+ writel_relaxed(val, ss->base + SPRD_SPI_CTL7);
+}
+
+static int sprd_spi_setup_transfer(struct spi_device *sdev,
+ struct spi_transfer *t)
+{
+ struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller);
+ u8 bits_per_word = t->bits_per_word;
+ u32 val, mode = 0;
+
+ ss->len = t->len;
+ ss->tx_buf = t->tx_buf;
+ ss->rx_buf = t->rx_buf;
+
+ ss->hw_mode = sdev->mode;
+ sprd_spi_init_hw(ss, t);
+
+ /* Set tansfer speed and valid bits */
+ sprd_spi_set_speed(ss, t->speed_hz);
+ sprd_spi_set_transfer_bits(ss, bits_per_word);
+
+ if (bits_per_word > 16)
+ bits_per_word = round_up(bits_per_word, 16);
+ else
+ bits_per_word = round_up(bits_per_word, 8);
+
+ switch (bits_per_word) {
+ case 8:
+ ss->trans_len = t->len;
+ ss->read_bufs = sprd_spi_read_bufs_u8;
+ ss->write_bufs = sprd_spi_write_bufs_u8;
+ break;
+ case 16:
+ ss->trans_len = t->len >> 1;
+ ss->read_bufs = sprd_spi_read_bufs_u16;
+ ss->write_bufs = sprd_spi_write_bufs_u16;
+ break;
+ case 32:
+ ss->trans_len = t->len >> 2;
+ ss->read_bufs = sprd_spi_read_bufs_u32;
+ ss->write_bufs = sprd_spi_write_bufs_u32;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* Set transfer read or write mode */
+ val = readl_relaxed(ss->base + SPRD_SPI_CTL1);
+ val &= ~SPRD_SPI_RTX_MD_MASK;
+ if (t->tx_buf)
+ mode |= SPRD_SPI_TX_MODE;
+ if (t->rx_buf)
+ mode |= SPRD_SPI_RX_MODE;
+
+ writel_relaxed(val | mode, ss->base + SPRD_SPI_CTL1);
+
+ ss->trans_mode = mode;
+
+ /*
+ * If in only receive mode, we need to trigger the SPI controller to
+ * receive data automatically.
+ */
+ if (ss->trans_mode == SPRD_SPI_RX_MODE)
+ ss->write_bufs = sprd_spi_write_only_receive;
+
+ return 0;
+}
+
+static int sprd_spi_transfer_one(struct spi_controller *sctlr,
+ struct spi_device *sdev,
+ struct spi_transfer *t)
+{
+ int ret;
+
+ ret = sprd_spi_setup_transfer(sdev, t);
+ if (ret)
+ goto setup_err;
+
+ ret = sprd_spi_txrx_bufs(sdev, t);
+ if (ret == t->len)
+ ret = 0;
+ else if (ret >= 0)
+ ret = -EREMOTEIO;
+
+setup_err:
+ spi_finalize_current_transfer(sctlr);
+
+ return ret;
+}
+
+static int sprd_spi_clk_init(struct platform_device *pdev, struct sprd_spi *ss)
+{
+ struct clk *clk_spi, *clk_parent;
+
+ clk_spi = devm_clk_get(&pdev->dev, "spi");
+ if (IS_ERR(clk_spi)) {
+ dev_warn(&pdev->dev, "can't get the spi clock\n");
+ clk_spi = NULL;
+ }
+
+ clk_parent = devm_clk_get(&pdev->dev, "source");
+ if (IS_ERR(clk_parent)) {
+ dev_warn(&pdev->dev, "can't get the source clock\n");
+ clk_parent = NULL;
+ }
+
+ ss->clk = devm_clk_get(&pdev->dev, "enable");
+ if (IS_ERR(ss->clk)) {
+ dev_err(&pdev->dev, "can't get the enable clock\n");
+ return PTR_ERR(ss->clk);
+ }
+
+ if (!clk_set_parent(clk_spi, clk_parent))
+ ss->src_clk = clk_get_rate(clk_spi);
+ else
+ ss->src_clk = SPRD_SPI_DEFAULT_SOURCE;
+
+ return 0;
+}
+
+static int sprd_spi_probe(struct platform_device *pdev)
+{
+ struct spi_controller *sctlr;
+ struct resource *res;
+ struct sprd_spi *ss;
+ int ret;
+
+ pdev->id = of_alias_get_id(pdev->dev.of_node, "spi");
+ sctlr = spi_alloc_master(&pdev->dev, sizeof(*ss));
+ if (!sctlr)
+ return -ENOMEM;
+
+ ss = spi_controller_get_devdata(sctlr);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ss->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ss->base)) {
+ ret = PTR_ERR(ss->base);
+ goto free_controller;
+ }
+
+ ss->dev = &pdev->dev;
+ sctlr->dev.of_node = pdev->dev.of_node;
+ sctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE | SPI_TX_DUAL;
+ sctlr->bus_num = pdev->id;
+ sctlr->set_cs = sprd_spi_chipselect;
+ sctlr->transfer_one = sprd_spi_transfer_one;
+ sctlr->auto_runtime_pm = true;
+ sctlr->max_speed_hz = min_t(u32, ss->src_clk >> 1,
+ SPRD_SPI_MAX_SPEED_HZ);
+
+ platform_set_drvdata(pdev, sctlr);
+ ret = sprd_spi_clk_init(pdev, ss);
+ if (ret)
+ goto free_controller;
+
+ ret = clk_prepare_enable(ss->clk);
+ if (ret)
+ goto free_controller;
+
+ ret = pm_runtime_set_active(&pdev->dev);
+ if (ret < 0)
+ goto disable_clk;
+
+ pm_runtime_set_autosuspend_delay(&pdev->dev,
+ SPRD_SPI_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to resume SPI controller\n");
+ goto err_rpm_put;
+ }
+
+ ret = devm_spi_register_controller(&pdev->dev, sctlr);
+ if (ret)
+ goto err_rpm_put;
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
+ return 0;
+
+err_rpm_put:
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+disable_clk:
+ clk_disable_unprepare(ss->clk);
+free_controller:
+ spi_controller_put(sctlr);
+
+ return ret;
+}
+
+static int __exit sprd_spi_remove(struct platform_device *pdev)
+{
+ struct spi_controller *sctlr = platform_get_drvdata(pdev);
+ struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
+ int ret;
+
+ ret = pm_runtime_get_sync(ss->dev);
+ if (ret < 0) {
+ dev_err(ss->dev, "failed to resume SPI controller\n");
+ return ret;
+ }
+
+ clk_disable_unprepare(ss->clk);
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static int __maybe_unused sprd_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_controller *sctlr = dev_get_drvdata(dev);
+ struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
+
+ clk_disable_unprepare(ss->clk);
+
+ return 0;
+}
+
+static int __maybe_unused sprd_spi_runtime_resume(struct device *dev)
+{
+ struct spi_controller *sctlr = dev_get_drvdata(dev);
+ struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
+ int ret;
+
+ ret = clk_prepare_enable(ss->clk);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct dev_pm_ops sprd_spi_pm_ops = {
+ SET_RUNTIME_PM_OPS(sprd_spi_runtime_suspend,
+ sprd_spi_runtime_resume, NULL)
+};
+
+static const struct of_device_id sprd_spi_of_match[] = {
+ { .compatible = "sprd,sc9860-spi", },
+ { /* sentinel */ }
+};
+
+static struct platform_driver sprd_spi_driver = {
+ .driver = {
+ .name = "sprd-spi",
+ .of_match_table = sprd_spi_of_match,
+ .pm = &sprd_spi_pm_ops,
+ },
+ .probe = sprd_spi_probe,
+ .remove = sprd_spi_remove,
+};
+
+module_platform_driver(sprd_spi_driver);
+
+MODULE_DESCRIPTION("Spreadtrum SPI Controller driver");
+MODULE_AUTHOR("Lanqing Liu <lanqing.liu@xxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
