diff options
Diffstat (limited to 'drivers/spi/ftssp010_spi.c')
| -rw-r--r-- | drivers/spi/ftssp010_spi.c | 508 |
1 files changed, 508 insertions, 0 deletions
diff --git a/drivers/spi/ftssp010_spi.c b/drivers/spi/ftssp010_spi.c new file mode 100644 index 0000000..aa3b5a0 --- /dev/null +++ b/drivers/spi/ftssp010_spi.c @@ -0,0 +1,508 @@ +/* + * (C) Copyright 2013 + * Faraday Technology Corporation. <http://www.faraday-tech.com/tw/> + * Kuo-Jung Su <dantesu@gmail.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <linux/compat.h> +#include <asm/io.h> +#include <malloc.h> +#include <spi.h> + +#ifndef CONFIG_FTSSP010_BASE_LIST +#define CONFIG_FTSSP010_BASE_LIST { CONFIG_FTSSP010_BASE } +#endif + +#ifndef CONFIG_FTSSP010_GPIO_BASE +#define CONFIG_FTSSP010_GPIO_BASE 0 +#endif + +#ifndef CONFIG_FTSSP010_GPIO_LIST +#define CONFIG_FTSSP010_GPIO_LIST { CONFIG_FTSSP010_GPIO_BASE } +#endif + +#ifndef CONFIG_FTSSP010_CLOCK +#define CONFIG_FTSSP010_CLOCK clk_get_rate("SSP"); +#endif + +#ifndef CONFIG_FTSSP010_TIMEOUT +#define CONFIG_FTSSP010_TIMEOUT 100 +#endif + +/* FTSSP010 chip registers */ +struct ftssp010_regs { + uint32_t cr[3];/* control register */ + uint32_t sr; /* status register */ + uint32_t icr; /* interrupt control register */ + uint32_t isr; /* interrupt status register */ + uint32_t dr; /* data register */ + uint32_t rsvd[17]; + uint32_t revr; /* revision register */ + uint32_t fear; /* feature register */ +}; + +/* Control Register 0 */ +#define CR0_FFMT_MASK (7 << 12) +#define CR0_FFMT_SSP (0 << 12) +#define CR0_FFMT_SPI (1 << 12) +#define CR0_FFMT_MICROWIRE (2 << 12) +#define CR0_FFMT_I2S (3 << 12) +#define CR0_FFMT_AC97 (4 << 12) +#define CR0_FLASH (1 << 11) +#define CR0_FSDIST(x) (((x) & 0x03) << 8) +#define CR0_LOOP (1 << 7) /* loopback mode */ +#define CR0_LSB (1 << 6) /* LSB */ +#define CR0_FSPO (1 << 5) /* fs atcive low (I2S only) */ +#define CR0_FSJUSTIFY (1 << 4) +#define CR0_OPM_SLAVE (0 << 2) +#define CR0_OPM_MASTER (3 << 2) +#define CR0_OPM_I2S_MSST (3 << 2) /* master stereo mode */ +#define CR0_OPM_I2S_MSMO (2 << 2) /* master mono mode */ +#define CR0_OPM_I2S_SLST (1 << 2) /* slave stereo mode */ +#define CR0_OPM_I2S_SLMO (0 << 2) /* slave mono mode */ +#define CR0_SCLKPO (1 << 1) /* clock polarity */ +#define CR0_SCLKPH (1 << 0) /* clock phase */ + +/* Control Register 1 */ +#define CR1_PDL(x) (((x) & 0xff) << 24) /* padding length */ +#define CR1_SDL(x) ((((x) - 1) & 0x1f) << 16) /* data length */ +#define CR1_DIV(x) (((x) - 1) & 0xffff) /* clock divider */ + +/* Control Register 2 */ +#define CR2_CS(x) (((x) & 3) << 10) /* CS/FS select */ +#define CR2_FS (1 << 9) /* CS/FS signal level */ +#define CR2_TXEN (1 << 8) /* tx enable */ +#define CR2_RXEN (1 << 7) /* rx enable */ +#define CR2_RESET (1 << 6) /* chip reset */ +#define CR2_TXFC (1 << 3) /* tx fifo Clear */ +#define CR2_RXFC (1 << 2) /* rx fifo Clear */ +#define CR2_TXDOE (1 << 1) /* tx data output enable */ +#define CR2_EN (1 << 0) /* chip enable */ + +/* Status Register */ +#define SR_RFF (1 << 0) /* rx fifo full */ +#define SR_TFNF (1 << 1) /* tx fifo not full */ +#define SR_BUSY (1 << 2) /* chip busy */ +#define SR_RFVE(reg) (((reg) >> 4) & 0x1f) /* rx fifo valid entries */ +#define SR_TFVE(reg) (((reg) >> 12) & 0x1f) /* tx fifo valid entries */ + +/* Feature Register */ +#define FEAR_BITS(reg) ((((reg) >> 0) & 0xff) + 1) /* data width */ +#define FEAR_RFSZ(reg) ((((reg) >> 8) & 0xff) + 1) /* rx fifo size */ +#define FEAR_TFSZ(reg) ((((reg) >> 16) & 0xff) + 1) /* tx fifo size */ +#define FEAR_AC97 (1 << 24) +#define FEAR_I2S (1 << 25) +#define FEAR_SPI_MWR (1 << 26) +#define FEAR_SSP (1 << 27) +#define FEAR_SPDIF (1 << 28) + +/* FTGPIO010 chip registers */ +struct ftgpio010_regs { + uint32_t out; /* 0x00: Data Output */ + uint32_t in; /* 0x04: Data Input */ + uint32_t dir; /* 0x08: Direction */ + uint32_t bypass; /* 0x0c: Bypass */ + uint32_t set; /* 0x10: Data Set */ + uint32_t clr; /* 0x14: Data Clear */ + uint32_t pull_up; /* 0x18: Pull-Up Enabled */ + uint32_t pull_st; /* 0x1c: Pull State (0=pull-down, 1=pull-up) */ +}; + +struct ftssp010_gpio { + struct ftgpio010_regs *regs; + uint32_t pin; +}; + +struct ftssp010_spi { + struct spi_slave slave; + struct ftssp010_gpio gpio; + struct ftssp010_regs *regs; + uint32_t fifo; + uint32_t mode; + uint32_t div; + uint32_t clk; + uint32_t speed; + uint32_t revision; +}; + +static inline struct ftssp010_spi *to_ftssp010_spi(struct spi_slave *slave) +{ + return container_of(slave, struct ftssp010_spi, slave); +} + +static int get_spi_chip(int bus, struct ftssp010_spi *chip) +{ + uint32_t fear, base[] = CONFIG_FTSSP010_BASE_LIST; + + if (bus >= ARRAY_SIZE(base) || !base[bus]) + return -1; + + chip->regs = (struct ftssp010_regs *)base[bus]; + + chip->revision = readl(&chip->regs->revr); + + fear = readl(&chip->regs->fear); + chip->fifo = min_t(uint32_t, FEAR_TFSZ(fear), FEAR_RFSZ(fear)); + + return 0; +} + +static int get_spi_gpio(int bus, struct ftssp010_gpio *chip) +{ + uint32_t base[] = CONFIG_FTSSP010_GPIO_LIST; + + if (bus >= ARRAY_SIZE(base) || !base[bus]) + return -1; + + chip->regs = (struct ftgpio010_regs *)(base[bus] & 0xfff00000); + chip->pin = base[bus] & 0x1f; + + /* make it an output pin */ + setbits_le32(&chip->regs->dir, 1 << chip->pin); + + return 0; +} + +static int ftssp010_wait(struct ftssp010_spi *chip) +{ + struct ftssp010_regs *regs = chip->regs; + int ret = -1; + ulong t; + + /* wait until device idle */ + for (t = get_timer(0); get_timer(t) < CONFIG_FTSSP010_TIMEOUT; ) { + if (readl(®s->sr) & SR_BUSY) + continue; + ret = 0; + break; + } + + if (ret) + puts("ftspi010: busy timeout\n"); + + return ret; +} + +static int ftssp010_wait_tx(struct ftssp010_spi *chip) +{ + struct ftssp010_regs *regs = chip->regs; + int ret = -1; + ulong t; + + /* wait until tx fifo not full */ + for (t = get_timer(0); get_timer(t) < CONFIG_FTSSP010_TIMEOUT; ) { + if (!(readl(®s->sr) & SR_TFNF)) + continue; + ret = 0; + break; + } + + if (ret) + puts("ftssp010: tx timeout\n"); + + return ret; +} + +static int ftssp010_wait_rx(struct ftssp010_spi *chip) +{ + struct ftssp010_regs *regs = chip->regs; + int ret = -1; + ulong t; + + /* wait until rx fifo not empty */ + for (t = get_timer(0); get_timer(t) < CONFIG_FTSSP010_TIMEOUT; ) { + if (!SR_RFVE(readl(®s->sr))) + continue; + ret = 0; + break; + } + + if (ret) + puts("ftssp010: rx timeout\n"); + + return ret; +} + +static int ftssp010_spi_work_transfer_v2(struct ftssp010_spi *chip, + const void *tx_buf, void *rx_buf, int len, uint flags) +{ + struct ftssp010_regs *regs = chip->regs; + const uint8_t *txb = tx_buf; + uint8_t *rxb = rx_buf; + + while (len > 0) { + int i, depth = min(chip->fifo >> 2, len); + uint32_t xmsk = 0; + + if (tx_buf) { + for (i = 0; i < depth; ++i) { + ftssp010_wait_tx(chip); + writel(*txb++, ®s->dr); + } + xmsk |= CR2_TXEN | CR2_TXDOE; + if ((readl(®s->cr[2]) & xmsk) != xmsk) + setbits_le32(®s->cr[2], xmsk); + } + if (rx_buf) { + xmsk |= CR2_RXEN; + if ((readl(®s->cr[2]) & xmsk) != xmsk) + setbits_le32(®s->cr[2], xmsk); + for (i = 0; i < depth; ++i) { + ftssp010_wait_rx(chip); + *rxb++ = (uint8_t)readl(®s->dr); + } + } + + len -= depth; + } + + return 0; +} + +static int ftssp010_spi_work_transfer_v1(struct ftssp010_spi *chip, + const void *tx_buf, void *rx_buf, int len, uint flags) +{ + struct ftssp010_regs *regs = chip->regs; + const uint8_t *txb = tx_buf; + uint8_t *rxb = rx_buf; + + while (len > 0) { + int i, depth = min(chip->fifo >> 2, len); + uint32_t tmp; + + for (i = 0; i < depth; ++i) { + ftssp010_wait_tx(chip); + writel(txb ? (*txb++) : 0, ®s->dr); + } + for (i = 0; i < depth; ++i) { + ftssp010_wait_rx(chip); + tmp = readl(®s->dr); + if (rxb) + *rxb++ = (uint8_t)tmp; + } + + len -= depth; + } + + return 0; +} + +static void ftssp010_cs_set(struct ftssp010_spi *chip, int high) +{ + struct ftssp010_regs *regs = chip->regs; + struct ftssp010_gpio *gpio = &chip->gpio; + uint32_t mask; + + /* cs pull high/low */ + if (chip->revision >= 0x11900) { + mask = CR2_CS(chip->slave.cs) | (high ? CR2_FS : 0); + writel(mask, ®s->cr[2]); + } else if (gpio->regs) { + mask = 1 << gpio->pin; + if (high) + writel(mask, &gpio->regs->set); + else + writel(mask, &gpio->regs->clr); + } + + /* extra delay for signal propagation */ + udelay_masked(1); +} + +/* + * Determine if a SPI chipselect is valid. + * This function is provided by the board if the low-level SPI driver + * needs it to determine if a given chipselect is actually valid. + * + * Returns: 1 if bus:cs identifies a valid chip on this board, 0 + * otherwise. + */ +int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ + struct ftssp010_spi chip; + + if (get_spi_chip(bus, &chip)) + return 0; + + if (!cs) + return 1; + else if ((cs < 4) && (chip.revision >= 0x11900)) + return 1; + + return 0; +} + +/* + * Activate a SPI chipselect. + * This function is provided by the board code when using a driver + * that can't control its chipselects automatically (e.g. + * common/soft_spi.c). When called, it should activate the chip select + * to the device identified by "slave". + */ +void spi_cs_activate(struct spi_slave *slave) +{ + struct ftssp010_spi *chip = to_ftssp010_spi(slave); + struct ftssp010_regs *regs = chip->regs; + + /* cs pull */ + if (chip->mode & SPI_CS_HIGH) + ftssp010_cs_set(chip, 1); + else + ftssp010_cs_set(chip, 0); + + /* chip enable + fifo clear */ + setbits_le32(®s->cr[2], CR2_EN | CR2_TXFC | CR2_RXFC); +} + +/* + * Deactivate a SPI chipselect. + * This function is provided by the board code when using a driver + * that can't control its chipselects automatically (e.g. + * common/soft_spi.c). When called, it should deactivate the chip + * select to the device identified by "slave". + */ +void spi_cs_deactivate(struct spi_slave *slave) +{ + struct ftssp010_spi *chip = to_ftssp010_spi(slave); + + /* wait until chip idle */ + ftssp010_wait(chip); + + /* cs pull */ + if (chip->mode & SPI_CS_HIGH) + ftssp010_cs_set(chip, 0); + else + ftssp010_cs_set(chip, 1); +} + +void spi_init(void) +{ + /* nothing to do */ +} + +struct spi_slave *spi_setup_slave(uint bus, uint cs, uint max_hz, uint mode) +{ + struct ftssp010_spi *chip; + + if (mode & SPI_3WIRE) { + puts("ftssp010: can't do 3-wire\n"); + return NULL; + } + + if (mode & SPI_SLAVE) { + puts("ftssp010: can't do slave mode\n"); + return NULL; + } + + if (mode & SPI_PREAMBLE) { + puts("ftssp010: can't skip preamble bytes\n"); + return NULL; + } + + if (!spi_cs_is_valid(bus, cs)) { + puts("ftssp010: invalid (bus, cs)\n"); + return NULL; + } + + chip = spi_alloc_slave(struct ftssp010_spi, bus, cs); + if (!chip) + return NULL; + + if (get_spi_chip(bus, chip)) + goto free_out; + + if (chip->revision < 0x11900 && get_spi_gpio(bus, &chip->gpio)) { + puts("ftssp010: Before revision 1.19.0, its clock & cs are\n" + "controlled by tx engine which is not synced with rx engine,\n" + "so the clock & cs might be shutdown before rx engine\n" + "finishs its jobs.\n" + "If possible, please add a dedicated gpio for it.\n"); + } + + chip->mode = mode; + chip->clk = CONFIG_FTSSP010_CLOCK; + chip->div = 2; + if (max_hz) { + while (chip->div < 0xffff) { + if ((chip->clk / (2 * chip->div)) <= max_hz) + break; + chip->div += 1; + } + } + chip->speed = chip->clk / (2 * chip->div); + + return &chip->slave; + +free_out: + free(chip); + return NULL; +} + +void spi_free_slave(struct spi_slave *slave) +{ + free(slave); +} + +int spi_claim_bus(struct spi_slave *slave) +{ + struct ftssp010_spi *chip = to_ftssp010_spi(slave); + struct ftssp010_regs *regs = chip->regs; + + writel(CR1_SDL(8) | CR1_DIV(chip->div), ®s->cr[1]); + + if (chip->revision >= 0x11900) { + writel(CR0_OPM_MASTER | CR0_FFMT_SPI | CR0_FSPO | CR0_FLASH, + ®s->cr[0]); + writel(CR2_TXFC | CR2_RXFC, + ®s->cr[2]); + } else { + writel(CR0_OPM_MASTER | CR0_FFMT_SPI | CR0_FSPO, + ®s->cr[0]); + writel(CR2_TXFC | CR2_RXFC | CR2_EN | CR2_TXDOE, + ®s->cr[2]); + } + + if (chip->mode & SPI_LOOP) + setbits_le32(®s->cr[0], CR0_LOOP); + + if (chip->mode & SPI_CPOL) + setbits_le32(®s->cr[0], CR0_SCLKPO); + + if (chip->mode & SPI_CPHA) + setbits_le32(®s->cr[0], CR0_SCLKPH); + + spi_cs_deactivate(slave); + + return 0; +} + +void spi_release_bus(struct spi_slave *slave) +{ + struct ftssp010_spi *chip = to_ftssp010_spi(slave); + struct ftssp010_regs *regs = chip->regs; + + writel(0, ®s->cr[2]); +} + +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct ftssp010_spi *chip = to_ftssp010_spi(slave); + uint32_t len = bitlen >> 3; + + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(slave); + + if (chip->revision >= 0x11900) + ftssp010_spi_work_transfer_v2(chip, dout, din, len, flags); + else + ftssp010_spi_work_transfer_v1(chip, dout, din, len, flags); + + if (flags & SPI_XFER_END) + spi_cs_deactivate(slave); + + return 0; +} |