diff options
Diffstat (limited to 'drivers/spi/spi-fsl-lpspi.c')
| -rw-r--r-- | drivers/spi/spi-fsl-lpspi.c | 992 |
1 files changed, 992 insertions, 0 deletions
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c new file mode 100644 index 000000000..c5ff6e8c4 --- /dev/null +++ b/drivers/spi/spi-fsl-lpspi.c @@ -0,0 +1,992 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Freescale i.MX7ULP LPSPI driver +// +// Copyright 2016 Freescale Semiconductor, Inc. +// Copyright 2018 NXP Semiconductors + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/platform_data/dma-imx.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_bitbang.h> +#include <linux/types.h> + +#define DRIVER_NAME "fsl_lpspi" + +#define FSL_LPSPI_RPM_TIMEOUT 50 /* 50ms */ + +/* The maximum bytes that edma can transfer once.*/ +#define FSL_LPSPI_MAX_EDMA_BYTES ((1 << 15) - 1) + +/* i.MX7ULP LPSPI registers */ +#define IMX7ULP_VERID 0x0 +#define IMX7ULP_PARAM 0x4 +#define IMX7ULP_CR 0x10 +#define IMX7ULP_SR 0x14 +#define IMX7ULP_IER 0x18 +#define IMX7ULP_DER 0x1c +#define IMX7ULP_CFGR0 0x20 +#define IMX7ULP_CFGR1 0x24 +#define IMX7ULP_DMR0 0x30 +#define IMX7ULP_DMR1 0x34 +#define IMX7ULP_CCR 0x40 +#define IMX7ULP_FCR 0x58 +#define IMX7ULP_FSR 0x5c +#define IMX7ULP_TCR 0x60 +#define IMX7ULP_TDR 0x64 +#define IMX7ULP_RSR 0x70 +#define IMX7ULP_RDR 0x74 + +/* General control register field define */ +#define CR_RRF BIT(9) +#define CR_RTF BIT(8) +#define CR_RST BIT(1) +#define CR_MEN BIT(0) +#define SR_MBF BIT(24) +#define SR_TCF BIT(10) +#define SR_FCF BIT(9) +#define SR_RDF BIT(1) +#define SR_TDF BIT(0) +#define IER_TCIE BIT(10) +#define IER_FCIE BIT(9) +#define IER_RDIE BIT(1) +#define IER_TDIE BIT(0) +#define DER_RDDE BIT(1) +#define DER_TDDE BIT(0) +#define CFGR1_PCSCFG BIT(27) +#define CFGR1_PINCFG (BIT(24)|BIT(25)) +#define CFGR1_PCSPOL BIT(8) +#define CFGR1_NOSTALL BIT(3) +#define CFGR1_MASTER BIT(0) +#define FSR_TXCOUNT (0xFF) +#define RSR_RXEMPTY BIT(1) +#define TCR_CPOL BIT(31) +#define TCR_CPHA BIT(30) +#define TCR_CONT BIT(21) +#define TCR_CONTC BIT(20) +#define TCR_RXMSK BIT(19) +#define TCR_TXMSK BIT(18) + +struct lpspi_config { + u8 bpw; + u8 chip_select; + u8 prescale; + u16 mode; + u32 speed_hz; +}; + +struct fsl_lpspi_data { + struct device *dev; + void __iomem *base; + unsigned long base_phys; + struct clk *clk_ipg; + struct clk *clk_per; + bool is_slave; + bool is_only_cs1; + bool is_first_byte; + + void *rx_buf; + const void *tx_buf; + void (*tx)(struct fsl_lpspi_data *); + void (*rx)(struct fsl_lpspi_data *); + + u32 remain; + u8 watermark; + u8 txfifosize; + u8 rxfifosize; + + struct lpspi_config config; + struct completion xfer_done; + + bool slave_aborted; + + /* DMA */ + bool usedma; + struct completion dma_rx_completion; + struct completion dma_tx_completion; +}; + +static const struct of_device_id fsl_lpspi_dt_ids[] = { + { .compatible = "fsl,imx7ulp-spi", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, fsl_lpspi_dt_ids); + +#define LPSPI_BUF_RX(type) \ +static void fsl_lpspi_buf_rx_##type(struct fsl_lpspi_data *fsl_lpspi) \ +{ \ + unsigned int val = readl(fsl_lpspi->base + IMX7ULP_RDR); \ + \ + if (fsl_lpspi->rx_buf) { \ + *(type *)fsl_lpspi->rx_buf = val; \ + fsl_lpspi->rx_buf += sizeof(type); \ + } \ +} + +#define LPSPI_BUF_TX(type) \ +static void fsl_lpspi_buf_tx_##type(struct fsl_lpspi_data *fsl_lpspi) \ +{ \ + type val = 0; \ + \ + if (fsl_lpspi->tx_buf) { \ + val = *(type *)fsl_lpspi->tx_buf; \ + fsl_lpspi->tx_buf += sizeof(type); \ + } \ + \ + fsl_lpspi->remain -= sizeof(type); \ + writel(val, fsl_lpspi->base + IMX7ULP_TDR); \ +} + +LPSPI_BUF_RX(u8) +LPSPI_BUF_TX(u8) +LPSPI_BUF_RX(u16) +LPSPI_BUF_TX(u16) +LPSPI_BUF_RX(u32) +LPSPI_BUF_TX(u32) + +static void fsl_lpspi_intctrl(struct fsl_lpspi_data *fsl_lpspi, + unsigned int enable) +{ + writel(enable, fsl_lpspi->base + IMX7ULP_IER); +} + +static int fsl_lpspi_bytes_per_word(const int bpw) +{ + return DIV_ROUND_UP(bpw, BITS_PER_BYTE); +} + +static bool fsl_lpspi_can_dma(struct spi_controller *controller, + struct spi_device *spi, + struct spi_transfer *transfer) +{ + unsigned int bytes_per_word; + + if (!controller->dma_rx) + return false; + + bytes_per_word = fsl_lpspi_bytes_per_word(transfer->bits_per_word); + + switch (bytes_per_word) { + case 1: + case 2: + case 4: + break; + default: + return false; + } + + return true; +} + +static int lpspi_prepare_xfer_hardware(struct spi_controller *controller) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + int ret; + + ret = pm_runtime_resume_and_get(fsl_lpspi->dev); + if (ret < 0) { + dev_err(fsl_lpspi->dev, "failed to enable clock\n"); + return ret; + } + + return 0; +} + +static int lpspi_unprepare_xfer_hardware(struct spi_controller *controller) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + + pm_runtime_mark_last_busy(fsl_lpspi->dev); + pm_runtime_put_autosuspend(fsl_lpspi->dev); + + return 0; +} + +static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi) +{ + u8 txfifo_cnt; + u32 temp; + + txfifo_cnt = readl(fsl_lpspi->base + IMX7ULP_FSR) & 0xff; + + while (txfifo_cnt < fsl_lpspi->txfifosize) { + if (!fsl_lpspi->remain) + break; + fsl_lpspi->tx(fsl_lpspi); + txfifo_cnt++; + } + + if (txfifo_cnt < fsl_lpspi->txfifosize) { + if (!fsl_lpspi->is_slave) { + temp = readl(fsl_lpspi->base + IMX7ULP_TCR); + temp &= ~TCR_CONTC; + writel(temp, fsl_lpspi->base + IMX7ULP_TCR); + } + + fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE); + } else + fsl_lpspi_intctrl(fsl_lpspi, IER_TDIE); +} + +static void fsl_lpspi_read_rx_fifo(struct fsl_lpspi_data *fsl_lpspi) +{ + while (!(readl(fsl_lpspi->base + IMX7ULP_RSR) & RSR_RXEMPTY)) + fsl_lpspi->rx(fsl_lpspi); +} + +static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi) +{ + u32 temp = 0; + + temp |= fsl_lpspi->config.bpw - 1; + temp |= (fsl_lpspi->config.mode & 0x3) << 30; + temp |= (fsl_lpspi->config.chip_select & 0x3) << 24; + if (!fsl_lpspi->is_slave) { + temp |= fsl_lpspi->config.prescale << 27; + /* + * Set TCR_CONT will keep SS asserted after current transfer. + * For the first transfer, clear TCR_CONTC to assert SS. + * For subsequent transfer, set TCR_CONTC to keep SS asserted. + */ + if (!fsl_lpspi->usedma) { + temp |= TCR_CONT; + if (fsl_lpspi->is_first_byte) + temp &= ~TCR_CONTC; + else + temp |= TCR_CONTC; + } + } + writel(temp, fsl_lpspi->base + IMX7ULP_TCR); + + dev_dbg(fsl_lpspi->dev, "TCR=0x%x\n", temp); +} + +static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi) +{ + u32 temp; + + if (!fsl_lpspi->usedma) + temp = fsl_lpspi->watermark >> 1 | + (fsl_lpspi->watermark >> 1) << 16; + else + temp = fsl_lpspi->watermark >> 1; + + writel(temp, fsl_lpspi->base + IMX7ULP_FCR); + + dev_dbg(fsl_lpspi->dev, "FCR=0x%x\n", temp); +} + +static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi) +{ + struct lpspi_config config = fsl_lpspi->config; + unsigned int perclk_rate, scldiv; + u8 prescale; + + perclk_rate = clk_get_rate(fsl_lpspi->clk_per); + + if (config.speed_hz > perclk_rate / 2) { + dev_err(fsl_lpspi->dev, + "per-clk should be at least two times of transfer speed"); + return -EINVAL; + } + + for (prescale = 0; prescale < 8; prescale++) { + scldiv = perclk_rate / config.speed_hz / (1 << prescale) - 2; + if (scldiv < 256) { + fsl_lpspi->config.prescale = prescale; + break; + } + } + + if (scldiv >= 256) + return -EINVAL; + + writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16), + fsl_lpspi->base + IMX7ULP_CCR); + + dev_dbg(fsl_lpspi->dev, "perclk=%d, speed=%d, prescale=%d, scldiv=%d\n", + perclk_rate, config.speed_hz, prescale, scldiv); + + return 0; +} + +static int fsl_lpspi_dma_configure(struct spi_controller *controller) +{ + int ret; + enum dma_slave_buswidth buswidth; + struct dma_slave_config rx = {}, tx = {}; + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + + switch (fsl_lpspi_bytes_per_word(fsl_lpspi->config.bpw)) { + case 4: + buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + case 2: + buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + case 1: + buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + default: + return -EINVAL; + } + + tx.direction = DMA_MEM_TO_DEV; + tx.dst_addr = fsl_lpspi->base_phys + IMX7ULP_TDR; + tx.dst_addr_width = buswidth; + tx.dst_maxburst = 1; + ret = dmaengine_slave_config(controller->dma_tx, &tx); + if (ret) { + dev_err(fsl_lpspi->dev, "TX dma configuration failed with %d\n", + ret); + return ret; + } + + rx.direction = DMA_DEV_TO_MEM; + rx.src_addr = fsl_lpspi->base_phys + IMX7ULP_RDR; + rx.src_addr_width = buswidth; + rx.src_maxburst = 1; + ret = dmaengine_slave_config(controller->dma_rx, &rx); + if (ret) { + dev_err(fsl_lpspi->dev, "RX dma configuration failed with %d\n", + ret); + return ret; + } + + return 0; +} + +static int fsl_lpspi_config(struct fsl_lpspi_data *fsl_lpspi) +{ + u32 temp; + int ret; + + if (!fsl_lpspi->is_slave) { + ret = fsl_lpspi_set_bitrate(fsl_lpspi); + if (ret) + return ret; + } + + fsl_lpspi_set_watermark(fsl_lpspi); + + if (!fsl_lpspi->is_slave) + temp = CFGR1_MASTER; + else + temp = CFGR1_PINCFG; + if (fsl_lpspi->config.mode & SPI_CS_HIGH) + temp |= CFGR1_PCSPOL; + writel(temp, fsl_lpspi->base + IMX7ULP_CFGR1); + + temp = readl(fsl_lpspi->base + IMX7ULP_CR); + temp |= CR_RRF | CR_RTF | CR_MEN; + writel(temp, fsl_lpspi->base + IMX7ULP_CR); + + temp = 0; + if (fsl_lpspi->usedma) + temp = DER_TDDE | DER_RDDE; + writel(temp, fsl_lpspi->base + IMX7ULP_DER); + + return 0; +} + +static int fsl_lpspi_setup_transfer(struct spi_controller *controller, + struct spi_device *spi, + struct spi_transfer *t) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(spi->controller); + + if (t == NULL) + return -EINVAL; + + fsl_lpspi->config.mode = spi->mode; + fsl_lpspi->config.bpw = t->bits_per_word; + fsl_lpspi->config.speed_hz = t->speed_hz; + if (fsl_lpspi->is_only_cs1) + fsl_lpspi->config.chip_select = 1; + else + fsl_lpspi->config.chip_select = spi->chip_select; + + if (!fsl_lpspi->config.speed_hz) + fsl_lpspi->config.speed_hz = spi->max_speed_hz; + if (!fsl_lpspi->config.bpw) + fsl_lpspi->config.bpw = spi->bits_per_word; + + /* Initialize the functions for transfer */ + if (fsl_lpspi->config.bpw <= 8) { + fsl_lpspi->rx = fsl_lpspi_buf_rx_u8; + fsl_lpspi->tx = fsl_lpspi_buf_tx_u8; + } else if (fsl_lpspi->config.bpw <= 16) { + fsl_lpspi->rx = fsl_lpspi_buf_rx_u16; + fsl_lpspi->tx = fsl_lpspi_buf_tx_u16; + } else { + fsl_lpspi->rx = fsl_lpspi_buf_rx_u32; + fsl_lpspi->tx = fsl_lpspi_buf_tx_u32; + } + + if (t->len <= fsl_lpspi->txfifosize) + fsl_lpspi->watermark = t->len; + else + fsl_lpspi->watermark = fsl_lpspi->txfifosize; + + if (fsl_lpspi_can_dma(controller, spi, t)) + fsl_lpspi->usedma = true; + else + fsl_lpspi->usedma = false; + + return fsl_lpspi_config(fsl_lpspi); +} + +static int fsl_lpspi_slave_abort(struct spi_controller *controller) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + + fsl_lpspi->slave_aborted = true; + if (!fsl_lpspi->usedma) + complete(&fsl_lpspi->xfer_done); + else { + complete(&fsl_lpspi->dma_tx_completion); + complete(&fsl_lpspi->dma_rx_completion); + } + + return 0; +} + +static int fsl_lpspi_wait_for_completion(struct spi_controller *controller) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + + if (fsl_lpspi->is_slave) { + if (wait_for_completion_interruptible(&fsl_lpspi->xfer_done) || + fsl_lpspi->slave_aborted) { + dev_dbg(fsl_lpspi->dev, "interrupted\n"); + return -EINTR; + } + } else { + if (!wait_for_completion_timeout(&fsl_lpspi->xfer_done, HZ)) { + dev_dbg(fsl_lpspi->dev, "wait for completion timeout\n"); + return -ETIMEDOUT; + } + } + + return 0; +} + +static int fsl_lpspi_reset(struct fsl_lpspi_data *fsl_lpspi) +{ + u32 temp; + + if (!fsl_lpspi->usedma) { + /* Disable all interrupt */ + fsl_lpspi_intctrl(fsl_lpspi, 0); + } + + /* W1C for all flags in SR */ + temp = 0x3F << 8; + writel(temp, fsl_lpspi->base + IMX7ULP_SR); + + /* Clear FIFO and disable module */ + temp = CR_RRF | CR_RTF; + writel(temp, fsl_lpspi->base + IMX7ULP_CR); + + return 0; +} + +static void fsl_lpspi_dma_rx_callback(void *cookie) +{ + struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie; + + complete(&fsl_lpspi->dma_rx_completion); +} + +static void fsl_lpspi_dma_tx_callback(void *cookie) +{ + struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie; + + complete(&fsl_lpspi->dma_tx_completion); +} + +static int fsl_lpspi_calculate_timeout(struct fsl_lpspi_data *fsl_lpspi, + int size) +{ + unsigned long timeout = 0; + + /* Time with actual data transfer and CS change delay related to HW */ + timeout = (8 + 4) * size / fsl_lpspi->config.speed_hz; + + /* Add extra second for scheduler related activities */ + timeout += 1; + + /* Double calculated timeout */ + return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC); +} + +static int fsl_lpspi_dma_transfer(struct spi_controller *controller, + struct fsl_lpspi_data *fsl_lpspi, + struct spi_transfer *transfer) +{ + struct dma_async_tx_descriptor *desc_tx, *desc_rx; + unsigned long transfer_timeout; + unsigned long timeout; + struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg; + int ret; + + ret = fsl_lpspi_dma_configure(controller); + if (ret) + return ret; + + desc_rx = dmaengine_prep_slave_sg(controller->dma_rx, + rx->sgl, rx->nents, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_rx) + return -EINVAL; + + desc_rx->callback = fsl_lpspi_dma_rx_callback; + desc_rx->callback_param = (void *)fsl_lpspi; + dmaengine_submit(desc_rx); + reinit_completion(&fsl_lpspi->dma_rx_completion); + dma_async_issue_pending(controller->dma_rx); + + desc_tx = dmaengine_prep_slave_sg(controller->dma_tx, + tx->sgl, tx->nents, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc_tx) { + dmaengine_terminate_all(controller->dma_tx); + return -EINVAL; + } + + desc_tx->callback = fsl_lpspi_dma_tx_callback; + desc_tx->callback_param = (void *)fsl_lpspi; + dmaengine_submit(desc_tx); + reinit_completion(&fsl_lpspi->dma_tx_completion); + dma_async_issue_pending(controller->dma_tx); + + fsl_lpspi->slave_aborted = false; + + if (!fsl_lpspi->is_slave) { + transfer_timeout = fsl_lpspi_calculate_timeout(fsl_lpspi, + transfer->len); + + /* Wait eDMA to finish the data transfer.*/ + timeout = wait_for_completion_timeout(&fsl_lpspi->dma_tx_completion, + transfer_timeout); + if (!timeout) { + dev_err(fsl_lpspi->dev, "I/O Error in DMA TX\n"); + dmaengine_terminate_all(controller->dma_tx); + dmaengine_terminate_all(controller->dma_rx); + fsl_lpspi_reset(fsl_lpspi); + return -ETIMEDOUT; + } + + timeout = wait_for_completion_timeout(&fsl_lpspi->dma_rx_completion, + transfer_timeout); + if (!timeout) { + dev_err(fsl_lpspi->dev, "I/O Error in DMA RX\n"); + dmaengine_terminate_all(controller->dma_tx); + dmaengine_terminate_all(controller->dma_rx); + fsl_lpspi_reset(fsl_lpspi); + return -ETIMEDOUT; + } + } else { + if (wait_for_completion_interruptible(&fsl_lpspi->dma_tx_completion) || + fsl_lpspi->slave_aborted) { + dev_dbg(fsl_lpspi->dev, + "I/O Error in DMA TX interrupted\n"); + dmaengine_terminate_all(controller->dma_tx); + dmaengine_terminate_all(controller->dma_rx); + fsl_lpspi_reset(fsl_lpspi); + return -EINTR; + } + + if (wait_for_completion_interruptible(&fsl_lpspi->dma_rx_completion) || + fsl_lpspi->slave_aborted) { + dev_dbg(fsl_lpspi->dev, + "I/O Error in DMA RX interrupted\n"); + dmaengine_terminate_all(controller->dma_tx); + dmaengine_terminate_all(controller->dma_rx); + fsl_lpspi_reset(fsl_lpspi); + return -EINTR; + } + } + + fsl_lpspi_reset(fsl_lpspi); + + return 0; +} + +static void fsl_lpspi_dma_exit(struct spi_controller *controller) +{ + if (controller->dma_rx) { + dma_release_channel(controller->dma_rx); + controller->dma_rx = NULL; + } + + if (controller->dma_tx) { + dma_release_channel(controller->dma_tx); + controller->dma_tx = NULL; + } +} + +static int fsl_lpspi_dma_init(struct device *dev, + struct fsl_lpspi_data *fsl_lpspi, + struct spi_controller *controller) +{ + int ret; + + /* Prepare for TX DMA: */ + controller->dma_tx = dma_request_chan(dev, "tx"); + if (IS_ERR(controller->dma_tx)) { + ret = PTR_ERR(controller->dma_tx); + dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret); + controller->dma_tx = NULL; + goto err; + } + + /* Prepare for RX DMA: */ + controller->dma_rx = dma_request_chan(dev, "rx"); + if (IS_ERR(controller->dma_rx)) { + ret = PTR_ERR(controller->dma_rx); + dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret); + controller->dma_rx = NULL; + goto err; + } + + init_completion(&fsl_lpspi->dma_rx_completion); + init_completion(&fsl_lpspi->dma_tx_completion); + controller->can_dma = fsl_lpspi_can_dma; + controller->max_dma_len = FSL_LPSPI_MAX_EDMA_BYTES; + + return 0; +err: + fsl_lpspi_dma_exit(controller); + return ret; +} + +static int fsl_lpspi_pio_transfer(struct spi_controller *controller, + struct spi_transfer *t) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + int ret; + + fsl_lpspi->tx_buf = t->tx_buf; + fsl_lpspi->rx_buf = t->rx_buf; + fsl_lpspi->remain = t->len; + + reinit_completion(&fsl_lpspi->xfer_done); + fsl_lpspi->slave_aborted = false; + + fsl_lpspi_write_tx_fifo(fsl_lpspi); + + ret = fsl_lpspi_wait_for_completion(controller); + if (ret) + return ret; + + fsl_lpspi_reset(fsl_lpspi); + + return 0; +} + +static int fsl_lpspi_transfer_one(struct spi_controller *controller, + struct spi_device *spi, + struct spi_transfer *t) +{ + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + int ret; + + fsl_lpspi->is_first_byte = true; + ret = fsl_lpspi_setup_transfer(controller, spi, t); + if (ret < 0) + return ret; + + fsl_lpspi_set_cmd(fsl_lpspi); + fsl_lpspi->is_first_byte = false; + + if (fsl_lpspi->usedma) + ret = fsl_lpspi_dma_transfer(controller, fsl_lpspi, t); + else + ret = fsl_lpspi_pio_transfer(controller, t); + if (ret < 0) + return ret; + + return 0; +} + +static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id) +{ + u32 temp_SR, temp_IER; + struct fsl_lpspi_data *fsl_lpspi = dev_id; + + temp_IER = readl(fsl_lpspi->base + IMX7ULP_IER); + fsl_lpspi_intctrl(fsl_lpspi, 0); + temp_SR = readl(fsl_lpspi->base + IMX7ULP_SR); + + fsl_lpspi_read_rx_fifo(fsl_lpspi); + + if ((temp_SR & SR_TDF) && (temp_IER & IER_TDIE)) { + fsl_lpspi_write_tx_fifo(fsl_lpspi); + return IRQ_HANDLED; + } + + if (temp_SR & SR_MBF || + readl(fsl_lpspi->base + IMX7ULP_FSR) & FSR_TXCOUNT) { + writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR); + fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE); + return IRQ_HANDLED; + } + + if (temp_SR & SR_FCF && (temp_IER & IER_FCIE)) { + writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR); + complete(&fsl_lpspi->xfer_done); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +#ifdef CONFIG_PM +static int fsl_lpspi_runtime_resume(struct device *dev) +{ + struct spi_controller *controller = dev_get_drvdata(dev); + struct fsl_lpspi_data *fsl_lpspi; + int ret; + + fsl_lpspi = spi_controller_get_devdata(controller); + + ret = clk_prepare_enable(fsl_lpspi->clk_per); + if (ret) + return ret; + + ret = clk_prepare_enable(fsl_lpspi->clk_ipg); + if (ret) { + clk_disable_unprepare(fsl_lpspi->clk_per); + return ret; + } + + return 0; +} + +static int fsl_lpspi_runtime_suspend(struct device *dev) +{ + struct spi_controller *controller = dev_get_drvdata(dev); + struct fsl_lpspi_data *fsl_lpspi; + + fsl_lpspi = spi_controller_get_devdata(controller); + + clk_disable_unprepare(fsl_lpspi->clk_per); + clk_disable_unprepare(fsl_lpspi->clk_ipg); + + return 0; +} +#endif + +static int fsl_lpspi_init_rpm(struct fsl_lpspi_data *fsl_lpspi) +{ + struct device *dev = fsl_lpspi->dev; + + pm_runtime_enable(dev); + pm_runtime_set_autosuspend_delay(dev, FSL_LPSPI_RPM_TIMEOUT); + pm_runtime_use_autosuspend(dev); + + return 0; +} + +static int fsl_lpspi_probe(struct platform_device *pdev) +{ + struct fsl_lpspi_data *fsl_lpspi; + struct spi_controller *controller; + struct resource *res; + int ret, irq; + u32 temp; + bool is_slave; + + is_slave = of_property_read_bool((&pdev->dev)->of_node, "spi-slave"); + if (is_slave) + controller = spi_alloc_slave(&pdev->dev, + sizeof(struct fsl_lpspi_data)); + else + controller = spi_alloc_master(&pdev->dev, + sizeof(struct fsl_lpspi_data)); + + if (!controller) + return -ENOMEM; + + platform_set_drvdata(pdev, controller); + + fsl_lpspi = spi_controller_get_devdata(controller); + fsl_lpspi->dev = &pdev->dev; + fsl_lpspi->is_slave = is_slave; + fsl_lpspi->is_only_cs1 = of_property_read_bool((&pdev->dev)->of_node, + "fsl,spi-only-use-cs1-sel"); + + controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32); + controller->transfer_one = fsl_lpspi_transfer_one; + controller->prepare_transfer_hardware = lpspi_prepare_xfer_hardware; + controller->unprepare_transfer_hardware = lpspi_unprepare_xfer_hardware; + controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + controller->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX; + controller->dev.of_node = pdev->dev.of_node; + controller->bus_num = pdev->id; + controller->slave_abort = fsl_lpspi_slave_abort; + if (!fsl_lpspi->is_slave) + controller->use_gpio_descriptors = true; + + init_completion(&fsl_lpspi->xfer_done); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + fsl_lpspi->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(fsl_lpspi->base)) { + ret = PTR_ERR(fsl_lpspi->base); + goto out_controller_put; + } + fsl_lpspi->base_phys = res->start; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = irq; + goto out_controller_put; + } + + ret = devm_request_irq(&pdev->dev, irq, fsl_lpspi_isr, 0, + dev_name(&pdev->dev), fsl_lpspi); + if (ret) { + dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret); + goto out_controller_put; + } + + fsl_lpspi->clk_per = devm_clk_get(&pdev->dev, "per"); + if (IS_ERR(fsl_lpspi->clk_per)) { + ret = PTR_ERR(fsl_lpspi->clk_per); + goto out_controller_put; + } + + fsl_lpspi->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(fsl_lpspi->clk_ipg)) { + ret = PTR_ERR(fsl_lpspi->clk_ipg); + goto out_controller_put; + } + + /* enable the clock */ + ret = fsl_lpspi_init_rpm(fsl_lpspi); + if (ret) + goto out_controller_put; + + ret = pm_runtime_get_sync(fsl_lpspi->dev); + if (ret < 0) { + dev_err(fsl_lpspi->dev, "failed to enable clock\n"); + goto out_pm_get; + } + + temp = readl(fsl_lpspi->base + IMX7ULP_PARAM); + fsl_lpspi->txfifosize = 1 << (temp & 0x0f); + fsl_lpspi->rxfifosize = 1 << ((temp >> 8) & 0x0f); + + ret = fsl_lpspi_dma_init(&pdev->dev, fsl_lpspi, controller); + if (ret == -EPROBE_DEFER) + goto out_pm_get; + if (ret < 0) + dev_err(&pdev->dev, "dma setup error %d, use pio\n", ret); + else + /* + * disable LPSPI module IRQ when enable DMA mode successfully, + * to prevent the unexpected LPSPI module IRQ events. + */ + disable_irq(irq); + + ret = devm_spi_register_controller(&pdev->dev, controller); + if (ret < 0) { + dev_err(&pdev->dev, "spi_register_controller error.\n"); + goto out_pm_get; + } + + pm_runtime_mark_last_busy(fsl_lpspi->dev); + pm_runtime_put_autosuspend(fsl_lpspi->dev); + + return 0; + +out_pm_get: + pm_runtime_dont_use_autosuspend(fsl_lpspi->dev); + pm_runtime_put_sync(fsl_lpspi->dev); + pm_runtime_disable(fsl_lpspi->dev); +out_controller_put: + spi_controller_put(controller); + + return ret; +} + +static int fsl_lpspi_remove(struct platform_device *pdev) +{ + struct spi_controller *controller = platform_get_drvdata(pdev); + struct fsl_lpspi_data *fsl_lpspi = + spi_controller_get_devdata(controller); + + pm_runtime_disable(fsl_lpspi->dev); + return 0; +} + +static int __maybe_unused fsl_lpspi_suspend(struct device *dev) +{ + int ret; + + pinctrl_pm_select_sleep_state(dev); + ret = pm_runtime_force_suspend(dev); + return ret; +} + +static int __maybe_unused fsl_lpspi_resume(struct device *dev) +{ + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret) { + dev_err(dev, "Error in resume: %d\n", ret); + return ret; + } + + pinctrl_pm_select_default_state(dev); + + return 0; +} + +static const struct dev_pm_ops fsl_lpspi_pm_ops = { + SET_RUNTIME_PM_OPS(fsl_lpspi_runtime_suspend, + fsl_lpspi_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(fsl_lpspi_suspend, fsl_lpspi_resume) +}; + +static struct platform_driver fsl_lpspi_driver = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = fsl_lpspi_dt_ids, + .pm = &fsl_lpspi_pm_ops, + }, + .probe = fsl_lpspi_probe, + .remove = fsl_lpspi_remove, +}; +module_platform_driver(fsl_lpspi_driver); + +MODULE_DESCRIPTION("LPSPI Controller driver"); +MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>"); +MODULE_LICENSE("GPL"); |