#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/spi/spi.h>
#define SP7021_DATA_RDY_REG 0x0044
#define SP7021_SLAVE_DMA_CTRL_REG 0x0048
#define SP7021_SLAVE_DMA_LENGTH_REG 0x004c
#define SP7021_SLAVE_DMA_ADDR_REG 0x004c
#define SP7021_SLAVE_DATA_RDY BIT(0)
#define SP7021_SLAVE_SW_RST BIT(1)
#define SP7021_SLA_DMA_W_INT BIT(8)
#define SP7021_SLAVE_CLR_INT BIT(8)
#define SP7021_SLAVE_DMA_EN BIT(0)
#define SP7021_SLAVE_DMA_RW BIT(6)
#define SP7021_SLAVE_DMA_CMD GENMASK(3, 2)
#define SP7021_FIFO_REG 0x0034
#define SP7021_SPI_STATUS_REG 0x0038
#define SP7021_SPI_CONFIG_REG 0x003c
#define SP7021_INT_BUSY_REG 0x004c
#define SP7021_DMA_CTRL_REG 0x0050
#define SP7021_SPI_START_FD BIT(0)
#define SP7021_FD_SW_RST BIT(1)
#define SP7021_TX_EMP_FLAG BIT(2)
#define SP7021_RX_EMP_FLAG BIT(4)
#define SP7021_RX_FULL_FLAG BIT(5)
#define SP7021_FINISH_FLAG BIT(6)
#define SP7021_TX_CNT_MASK GENMASK(11, 8)
#define SP7021_RX_CNT_MASK GENMASK(15, 12)
#define SP7021_TX_LEN_MASK GENMASK(23, 16)
#define SP7021_GET_LEN_MASK GENMASK(31, 24)
#define SP7021_SET_TX_LEN GENMASK(23, 16)
#define SP7021_SET_XFER_LEN GENMASK(31, 24)
#define SP7021_CPOL_FD BIT(0)
#define SP7021_CPHA_R BIT(1)
#define SP7021_CPHA_W BIT(2)
#define SP7021_LSB_SEL BIT(4)
#define SP7021_CS_POR BIT(5)
#define SP7021_FD_SEL BIT(6)
#define SP7021_RX_UNIT GENMASK(8, 7)
#define SP7021_TX_UNIT GENMASK(10, 9)
#define SP7021_TX_EMP_FLAG_MASK BIT(11)
#define SP7021_RX_FULL_FLAG_MASK BIT(14)
#define SP7021_FINISH_FLAG_MASK BIT(15)
#define SP7021_CLEAN_RW_BYTE GENMASK(10, 7)
#define SP7021_CLEAN_FLUG_MASK GENMASK(15, 11)
#define SP7021_CLK_MASK GENMASK(31, 16)
#define SP7021_INT_BYPASS BIT(3)
#define SP7021_CLR_MASTER_INT BIT(6)
#define SP7021_SPI_DATA_SIZE (255)
#define SP7021_FIFO_DATA_LEN (16)
enum {
SP7021_HOST_MODE = 0,
SP7021_TARGET_MODE = 1,
};
struct sp7021_spi_ctlr {
struct device *dev;
struct spi_controller *ctlr;
void __iomem *m_base;
void __iomem *s_base;
u32 xfer_conf;
int mode;
int m_irq;
int s_irq;
struct clk *spi_clk;
struct reset_control *rstc;
struct mutex buf_lock;
struct completion isr_done;
struct completion target_isr;
unsigned int rx_cur_len;
unsigned int tx_cur_len;
unsigned int data_unit;
const u8 *tx_buf;
u8 *rx_buf;
};
static irqreturn_t sp7021_spi_target_irq(int irq, void *dev)
{
struct sp7021_spi_ctlr *pspim = dev;
unsigned int data_status;
data_status = readl(pspim->s_base + SP7021_DATA_RDY_REG);
data_status |= SP7021_SLAVE_CLR_INT;
writel(data_status, pspim->s_base + SP7021_DATA_RDY_REG);
complete(&pspim->target_isr);
return IRQ_HANDLED;
}
static int sp7021_spi_target_abort(struct spi_controller *ctlr)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
complete(&pspim->target_isr);
complete(&pspim->isr_done);
return 0;
}
static int sp7021_spi_target_tx(struct spi_device *spi, struct spi_transfer *xfer)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
u32 value;
reinit_completion(&pspim->target_isr);
value = SP7021_SLAVE_DMA_EN | SP7021_SLAVE_DMA_RW | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
writel(xfer->tx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
value = readl(pspim->s_base + SP7021_DATA_RDY_REG);
value |= SP7021_SLAVE_DATA_RDY;
writel(value, pspim->s_base + SP7021_DATA_RDY_REG);
if (wait_for_completion_interruptible(&pspim->isr_done)) {
dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
return -EINTR;
}
return 0;
}
static int sp7021_spi_target_rx(struct spi_device *spi, struct spi_transfer *xfer)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
u32 value;
reinit_completion(&pspim->isr_done);
value = SP7021_SLAVE_DMA_EN | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
writel(xfer->rx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
if (wait_for_completion_interruptible(&pspim->isr_done)) {
dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
return -EINTR;
}
writel(SP7021_SLAVE_SW_RST, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
return 0;
}
static void sp7021_spi_host_rb(struct sp7021_spi_ctlr *pspim, unsigned int len)
{
int i;
for (i = 0; i < len; i++) {
pspim->rx_buf[pspim->rx_cur_len] =
readl(pspim->m_base + SP7021_FIFO_REG);
pspim->rx_cur_len++;
}
}
static void sp7021_spi_host_wb(struct sp7021_spi_ctlr *pspim, unsigned int len)
{
int i;
for (i = 0; i < len; i++) {
writel(pspim->tx_buf[pspim->tx_cur_len],
pspim->m_base + SP7021_FIFO_REG);
pspim->tx_cur_len++;
}
}
static irqreturn_t sp7021_spi_host_irq(int irq, void *dev)
{
struct sp7021_spi_ctlr *pspim = dev;
unsigned int tx_cnt, total_len;
unsigned int tx_len, rx_cnt;
unsigned int fd_status;
bool isrdone = false;
u32 value;
fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
tx_cnt = FIELD_GET(SP7021_TX_CNT_MASK, fd_status);
tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
if ((fd_status & SP7021_TX_EMP_FLAG) && (fd_status & SP7021_RX_EMP_FLAG) && total_len == 0)
return IRQ_NONE;
if (tx_len == 0 && total_len == 0)
return IRQ_NONE;
rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
if (fd_status & SP7021_RX_FULL_FLAG)
rx_cnt = pspim->data_unit;
tx_cnt = min(tx_len - pspim->tx_cur_len, pspim->data_unit - tx_cnt);
dev_dbg(pspim->dev, "fd_st=0x%x rx_c:%d tx_c:%d tx_l:%d",
fd_status, rx_cnt, tx_cnt, tx_len);
if (rx_cnt > 0)
sp7021_spi_host_rb(pspim, rx_cnt);
if (tx_cnt > 0)
sp7021_spi_host_wb(pspim, tx_cnt);
fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
if (fd_status & SP7021_FINISH_FLAG || tx_len == pspim->tx_cur_len) {
while (total_len != pspim->rx_cur_len) {
fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
if (fd_status & SP7021_RX_FULL_FLAG)
rx_cnt = pspim->data_unit;
else
rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
if (rx_cnt > 0)
sp7021_spi_host_rb(pspim, rx_cnt);
}
value = readl(pspim->m_base + SP7021_INT_BUSY_REG);
value |= SP7021_CLR_MASTER_INT;
writel(value, pspim->m_base + SP7021_INT_BUSY_REG);
writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
isrdone = true;
}
if (isrdone)
complete(&pspim->isr_done);
return IRQ_HANDLED;
}
static void sp7021_prep_transfer(struct spi_controller *ctlr, struct spi_device *spi)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
pspim->tx_cur_len = 0;
pspim->rx_cur_len = 0;
pspim->data_unit = SP7021_FIFO_DATA_LEN;
}
static int sp7021_spi_controller_prepare_message(struct spi_controller *ctlr,
struct spi_message *msg)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
struct spi_device *s = msg->spi;
u32 valus, rs = 0;
valus = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
valus |= SP7021_FD_SW_RST;
writel(valus, pspim->m_base + SP7021_SPI_STATUS_REG);
rs |= SP7021_FD_SEL;
if (s->mode & SPI_CPOL)
rs |= SP7021_CPOL_FD;
if (s->mode & SPI_LSB_FIRST)
rs |= SP7021_LSB_SEL;
if (s->mode & SPI_CS_HIGH)
rs |= SP7021_CS_POR;
if (s->mode & SPI_CPHA)
rs |= SP7021_CPHA_R;
else
rs |= SP7021_CPHA_W;
rs |= FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
pspim->xfer_conf = rs;
if (pspim->xfer_conf & SP7021_CPOL_FD)
writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
return 0;
}
static void sp7021_spi_setup_clk(struct spi_controller *ctlr, struct spi_transfer *xfer)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
u32 clk_rate, clk_sel, div;
clk_rate = clk_get_rate(pspim->spi_clk);
div = max(2U, clk_rate / xfer->speed_hz);
clk_sel = (div / 2) - 1;
pspim->xfer_conf &= ~SP7021_CLK_MASK;
pspim->xfer_conf |= FIELD_PREP(SP7021_CLK_MASK, clk_sel);
writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
}
static int sp7021_spi_host_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
struct spi_transfer *xfer)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
unsigned long timeout = msecs_to_jiffies(1000);
unsigned int xfer_cnt, xfer_len, last_len;
unsigned int i, len_temp;
u32 reg_temp;
xfer_cnt = xfer->len / SP7021_SPI_DATA_SIZE;
last_len = xfer->len % SP7021_SPI_DATA_SIZE;
for (i = 0; i <= xfer_cnt; i++) {
mutex_lock(&pspim->buf_lock);
sp7021_prep_transfer(ctlr, spi);
sp7021_spi_setup_clk(ctlr, xfer);
reinit_completion(&pspim->isr_done);
if (i == xfer_cnt)
xfer_len = last_len;
else
xfer_len = SP7021_SPI_DATA_SIZE;
pspim->tx_buf = xfer->tx_buf + i * SP7021_SPI_DATA_SIZE;
pspim->rx_buf = xfer->rx_buf + i * SP7021_SPI_DATA_SIZE;
if (pspim->tx_cur_len < xfer_len) {
len_temp = min(pspim->data_unit, xfer_len);
sp7021_spi_host_wb(pspim, len_temp);
}
reg_temp = readl(pspim->m_base + SP7021_SPI_CONFIG_REG);
reg_temp &= ~SP7021_CLEAN_RW_BYTE;
reg_temp &= ~SP7021_CLEAN_FLUG_MASK;
reg_temp |= SP7021_FD_SEL | SP7021_FINISH_FLAG_MASK |
SP7021_TX_EMP_FLAG_MASK | SP7021_RX_FULL_FLAG_MASK |
FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
writel(reg_temp, pspim->m_base + SP7021_SPI_CONFIG_REG);
reg_temp = FIELD_PREP(SP7021_SET_TX_LEN, xfer_len) |
FIELD_PREP(SP7021_SET_XFER_LEN, xfer_len) |
SP7021_SPI_START_FD;
writel(reg_temp, pspim->m_base + SP7021_SPI_STATUS_REG);
if (!wait_for_completion_interruptible_timeout(&pspim->isr_done, timeout)) {
dev_err(&spi->dev, "wait_for_completion err\n");
mutex_unlock(&pspim->buf_lock);
return -ETIMEDOUT;
}
reg_temp = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
if (reg_temp & SP7021_FINISH_FLAG) {
writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
writel(readl(pspim->m_base + SP7021_SPI_CONFIG_REG) &
SP7021_CLEAN_FLUG_MASK, pspim->m_base + SP7021_SPI_CONFIG_REG);
}
if (pspim->xfer_conf & SP7021_CPOL_FD)
writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
mutex_unlock(&pspim->buf_lock);
}
return 0;
}
static int sp7021_spi_target_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
struct spi_transfer *xfer)
{
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
struct device *dev = pspim->dev;
int ret;
if (xfer->tx_buf && !xfer->rx_buf) {
xfer->tx_dma = dma_map_single(dev, (void *)xfer->tx_buf,
xfer->len, DMA_TO_DEVICE);
if (dma_mapping_error(dev, xfer->tx_dma))
return -ENOMEM;
ret = sp7021_spi_target_tx(spi, xfer);
dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE);
} else if (xfer->rx_buf && !xfer->tx_buf) {
xfer->rx_dma = dma_map_single(dev, xfer->rx_buf, xfer->len,
DMA_FROM_DEVICE);
if (dma_mapping_error(dev, xfer->rx_dma))
return -ENOMEM;
ret = sp7021_spi_target_rx(spi, xfer);
dma_unmap_single(dev, xfer->rx_dma, xfer->len, DMA_FROM_DEVICE);
} else {
dev_dbg(&ctlr->dev, "%s() wrong command\n", __func__);
return -EINVAL;
}
spi_finalize_current_transfer(ctlr);
return ret;
}
static void sp7021_spi_disable_unprepare(void *data)
{
clk_disable_unprepare(data);
}
static void sp7021_spi_reset_control_assert(void *data)
{
reset_control_assert(data);
}
static int sp7021_spi_controller_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct sp7021_spi_ctlr *pspim;
struct spi_controller *ctlr;
int mode, ret;
pdev->id = of_alias_get_id(pdev->dev.of_node, "sp_spi");
if (device_property_read_bool(dev, "spi-slave"))
mode = SP7021_TARGET_MODE;
else
mode = SP7021_HOST_MODE;
if (mode == SP7021_TARGET_MODE)
ctlr = devm_spi_alloc_target(dev, sizeof(*pspim));
else
ctlr = devm_spi_alloc_host(dev, sizeof(*pspim));
if (!ctlr)
return -ENOMEM;
ctlr->bus_num = pdev->id;
ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
ctlr->auto_runtime_pm = true;
ctlr->prepare_message = sp7021_spi_controller_prepare_message;
if (mode == SP7021_TARGET_MODE) {
ctlr->transfer_one = sp7021_spi_target_transfer_one;
ctlr->target_abort = sp7021_spi_target_abort;
ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
} else {
ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
ctlr->min_speed_hz = 40000;
ctlr->max_speed_hz = 25000000;
ctlr->use_gpio_descriptors = true;
ctlr->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
ctlr->transfer_one = sp7021_spi_host_transfer_one;
}
platform_set_drvdata(pdev, ctlr);
pspim = spi_controller_get_devdata(ctlr);
pspim->mode = mode;
pspim->ctlr = ctlr;
pspim->dev = dev;
mutex_init(&pspim->buf_lock);
init_completion(&pspim->isr_done);
init_completion(&pspim->target_isr);
pspim->m_base = devm_platform_ioremap_resource_byname(pdev, "master");
if (IS_ERR(pspim->m_base))
return dev_err_probe(dev, PTR_ERR(pspim->m_base), "m_base get fail\n");
pspim->s_base = devm_platform_ioremap_resource_byname(pdev, "slave");
if (IS_ERR(pspim->s_base))
return dev_err_probe(dev, PTR_ERR(pspim->s_base), "s_base get fail\n");
pspim->m_irq = platform_get_irq_byname(pdev, "master_risc");
if (pspim->m_irq < 0)
return pspim->m_irq;
pspim->s_irq = platform_get_irq_byname(pdev, "slave_risc");
if (pspim->s_irq < 0)
return pspim->s_irq;
pspim->spi_clk = devm_clk_get(dev, NULL);
if (IS_ERR(pspim->spi_clk))
return dev_err_probe(dev, PTR_ERR(pspim->spi_clk), "clk get fail\n");
pspim->rstc = devm_reset_control_get_exclusive(dev, NULL);
if (IS_ERR(pspim->rstc))
return dev_err_probe(dev, PTR_ERR(pspim->rstc), "rst get fail\n");
ret = clk_prepare_enable(pspim->spi_clk);
if (ret)
return dev_err_probe(dev, ret, "failed to enable clk\n");
ret = devm_add_action_or_reset(dev, sp7021_spi_disable_unprepare, pspim->spi_clk);
if (ret)
return ret;
ret = reset_control_deassert(pspim->rstc);
if (ret)
return dev_err_probe(dev, ret, "failed to deassert reset\n");
ret = devm_add_action_or_reset(dev, sp7021_spi_reset_control_assert, pspim->rstc);
if (ret)
return ret;
ret = devm_request_irq(dev, pspim->m_irq, sp7021_spi_host_irq,
IRQF_TRIGGER_RISING, pdev->name, pspim);
if (ret)
return ret;
ret = devm_request_irq(dev, pspim->s_irq, sp7021_spi_target_irq,
IRQF_TRIGGER_RISING, pdev->name, pspim);
if (ret)
return ret;
pm_runtime_enable(dev);
ret = spi_register_controller(ctlr);
if (ret) {
pm_runtime_disable(dev);
return dev_err_probe(dev, ret, "spi_register_controller fail\n");
}
return 0;
}
static void sp7021_spi_controller_remove(struct platform_device *pdev)
{
struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
spi_unregister_controller(ctlr);
pm_runtime_disable(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
}
static int __maybe_unused sp7021_spi_controller_suspend(struct device *dev)
{
struct spi_controller *ctlr = dev_get_drvdata(dev);
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
return reset_control_assert(pspim->rstc);
}
static int __maybe_unused sp7021_spi_controller_resume(struct device *dev)
{
struct spi_controller *ctlr = dev_get_drvdata(dev);
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
reset_control_deassert(pspim->rstc);
return clk_prepare_enable(pspim->spi_clk);
}
#ifdef CONFIG_PM
static int sp7021_spi_runtime_suspend(struct device *dev)
{
struct spi_controller *ctlr = dev_get_drvdata(dev);
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
return reset_control_assert(pspim->rstc);
}
static int sp7021_spi_runtime_resume(struct device *dev)
{
struct spi_controller *ctlr = dev_get_drvdata(dev);
struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(ctlr);
return reset_control_deassert(pspim->rstc);
}
#endif
static const struct dev_pm_ops sp7021_spi_pm_ops = {
SET_RUNTIME_PM_OPS(sp7021_spi_runtime_suspend,
sp7021_spi_runtime_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(sp7021_spi_controller_suspend,
sp7021_spi_controller_resume)
};
static const struct of_device_id sp7021_spi_controller_ids[] = {
{ .compatible = "sunplus,sp7021-spi" },
{}
};
MODULE_DEVICE_TABLE(of, sp7021_spi_controller_ids);
static struct platform_driver sp7021_spi_controller_driver = {
.probe = sp7021_spi_controller_probe,
.remove = sp7021_spi_controller_remove,
.driver = {
.name = "sunplus,sp7021-spi-controller",
.of_match_table = sp7021_spi_controller_ids,
.pm = &sp7021_spi_pm_ops,
},
};
module_platform_driver(sp7021_spi_controller_driver);
MODULE_AUTHOR("Li-hao Kuo <lhjeff911@gmail.com>");
MODULE_DESCRIPTION("Sunplus SPI controller driver");
MODULE_LICENSE("GPL");
