/* * Marvell Armada-3700 SPI controller driver * * Copyright (C) 2016 Marvell Ltd. * * Author: Wilson Ding * Author: Romain Perier * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRIVER_NAME "armada_3700_spi" #define A3700_SPI_TIMEOUT 10 /* SPI Register Offest */ #define A3700_SPI_IF_CTRL_REG 0x00 #define A3700_SPI_IF_CFG_REG 0x04 #define A3700_SPI_DATA_OUT_REG 0x08 #define A3700_SPI_DATA_IN_REG 0x0C #define A3700_SPI_IF_INST_REG 0x10 #define A3700_SPI_IF_ADDR_REG 0x14 #define A3700_SPI_IF_RMODE_REG 0x18 #define A3700_SPI_IF_HDR_CNT_REG 0x1C #define A3700_SPI_IF_DIN_CNT_REG 0x20 #define A3700_SPI_IF_TIME_REG 0x24 #define A3700_SPI_INT_STAT_REG 0x28 #define A3700_SPI_INT_MASK_REG 0x2C /* A3700_SPI_IF_CTRL_REG */ #define A3700_SPI_EN BIT(16) #define A3700_SPI_ADDR_NOT_CONFIG BIT(12) #define A3700_SPI_WFIFO_OVERFLOW BIT(11) #define A3700_SPI_WFIFO_UNDERFLOW BIT(10) #define A3700_SPI_RFIFO_OVERFLOW BIT(9) #define A3700_SPI_RFIFO_UNDERFLOW BIT(8) #define A3700_SPI_WFIFO_FULL BIT(7) #define A3700_SPI_WFIFO_EMPTY BIT(6) #define A3700_SPI_RFIFO_FULL BIT(5) #define A3700_SPI_RFIFO_EMPTY BIT(4) #define A3700_SPI_WFIFO_RDY BIT(3) #define A3700_SPI_RFIFO_RDY BIT(2) #define A3700_SPI_XFER_RDY BIT(1) #define A3700_SPI_XFER_DONE BIT(0) /* A3700_SPI_IF_CFG_REG */ #define A3700_SPI_WFIFO_THRS BIT(28) #define A3700_SPI_RFIFO_THRS BIT(24) #define A3700_SPI_AUTO_CS BIT(20) #define A3700_SPI_DMA_RD_EN BIT(18) #define A3700_SPI_FIFO_MODE BIT(17) #define A3700_SPI_SRST BIT(16) #define A3700_SPI_XFER_START BIT(15) #define A3700_SPI_XFER_STOP BIT(14) #define A3700_SPI_INST_PIN BIT(13) #define A3700_SPI_ADDR_PIN BIT(12) #define A3700_SPI_DATA_PIN1 BIT(11) #define A3700_SPI_DATA_PIN0 BIT(10) #define A3700_SPI_FIFO_FLUSH BIT(9) #define A3700_SPI_RW_EN BIT(8) #define A3700_SPI_CLK_POL BIT(7) #define A3700_SPI_CLK_PHA BIT(6) #define A3700_SPI_BYTE_LEN BIT(5) #define A3700_SPI_CLK_PRESCALE BIT(0) #define A3700_SPI_CLK_PRESCALE_MASK (0x1f) #define A3700_SPI_WFIFO_THRS_BIT 28 #define A3700_SPI_RFIFO_THRS_BIT 24 #define A3700_SPI_FIFO_THRS_MASK 0x7 #define A3700_SPI_DATA_PIN_MASK 0x3 /* A3700_SPI_IF_HDR_CNT_REG */ #define A3700_SPI_DUMMY_CNT_BIT 12 #define A3700_SPI_DUMMY_CNT_MASK 0x7 #define A3700_SPI_RMODE_CNT_BIT 8 #define A3700_SPI_RMODE_CNT_MASK 0x3 #define A3700_SPI_ADDR_CNT_BIT 4 #define A3700_SPI_ADDR_CNT_MASK 0x7 #define A3700_SPI_INSTR_CNT_BIT 0 #define A3700_SPI_INSTR_CNT_MASK 0x3 /* A3700_SPI_IF_TIME_REG */ #define A3700_SPI_CLK_CAPT_EDGE BIT(7) /* Flags and macros for struct a3700_spi */ #define A3700_INSTR_CNT 1 #define A3700_ADDR_CNT 3 #define A3700_DUMMY_CNT 1 struct a3700_spi { struct spi_master *master; void __iomem *base; struct clk *clk; unsigned int irq; unsigned int flags; bool xmit_data; const u8 *tx_buf; u8 *rx_buf; size_t buf_len; u8 byte_len; u32 wait_mask; struct completion done; u32 addr_cnt; u32 instr_cnt; size_t hdr_cnt; }; static u32 spireg_read(struct a3700_spi *a3700_spi, u32 offset) { return readl(a3700_spi->base + offset); } static void spireg_write(struct a3700_spi *a3700_spi, u32 offset, u32 data) { writel(data, a3700_spi->base + offset); } static void a3700_spi_auto_cs_unset(struct a3700_spi *a3700_spi) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~A3700_SPI_AUTO_CS; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_activate_cs(struct a3700_spi *a3700_spi, unsigned int cs) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); val |= (A3700_SPI_EN << cs); spireg_write(a3700_spi, A3700_SPI_IF_CTRL_REG, val); } static void a3700_spi_deactivate_cs(struct a3700_spi *a3700_spi, unsigned int cs) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); val &= ~(A3700_SPI_EN << cs); spireg_write(a3700_spi, A3700_SPI_IF_CTRL_REG, val); } static int a3700_spi_pin_mode_set(struct a3700_spi *a3700_spi, unsigned int pin_mode) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~(A3700_SPI_INST_PIN | A3700_SPI_ADDR_PIN); val &= ~(A3700_SPI_DATA_PIN0 | A3700_SPI_DATA_PIN1); switch (pin_mode) { case 1: break; case 2: val |= A3700_SPI_DATA_PIN0; break; case 4: val |= A3700_SPI_DATA_PIN1; break; default: dev_err(&a3700_spi->master->dev, "wrong pin mode %u", pin_mode); return -EINVAL; } spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); return 0; } static void a3700_spi_fifo_mode_set(struct a3700_spi *a3700_spi) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= A3700_SPI_FIFO_MODE; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_mode_set(struct a3700_spi *a3700_spi, unsigned int mode_bits) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (mode_bits & SPI_CPOL) val |= A3700_SPI_CLK_POL; else val &= ~A3700_SPI_CLK_POL; if (mode_bits & SPI_CPHA) val |= A3700_SPI_CLK_PHA; else val &= ~A3700_SPI_CLK_PHA; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_clock_set(struct a3700_spi *a3700_spi, unsigned int speed_hz, u16 mode) { u32 val; u32 prescale; prescale = DIV_ROUND_UP(clk_get_rate(a3700_spi->clk), speed_hz); val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val = val & ~A3700_SPI_CLK_PRESCALE_MASK; val = val | (prescale & A3700_SPI_CLK_PRESCALE_MASK); spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); if (prescale <= 2) { val = spireg_read(a3700_spi, A3700_SPI_IF_TIME_REG); val |= A3700_SPI_CLK_CAPT_EDGE; spireg_write(a3700_spi, A3700_SPI_IF_TIME_REG, val); } val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~(A3700_SPI_CLK_POL | A3700_SPI_CLK_PHA); if (mode & SPI_CPOL) val |= A3700_SPI_CLK_POL; if (mode & SPI_CPHA) val |= A3700_SPI_CLK_PHA; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_bytelen_set(struct a3700_spi *a3700_spi, unsigned int len) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (len == 4) val |= A3700_SPI_BYTE_LEN; else val &= ~A3700_SPI_BYTE_LEN; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); a3700_spi->byte_len = len; } static int a3700_spi_fifo_flush(struct a3700_spi *a3700_spi) { int timeout = A3700_SPI_TIMEOUT; u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= A3700_SPI_FIFO_FLUSH; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); while (--timeout) { val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (!(val & A3700_SPI_FIFO_FLUSH)) return 0; udelay(1); } return -ETIMEDOUT; } static int a3700_spi_init(struct a3700_spi *a3700_spi) { struct spi_master *master = a3700_spi->master; u32 val; int i, ret = 0; /* Reset SPI unit */ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= A3700_SPI_SRST; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); udelay(A3700_SPI_TIMEOUT); val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~A3700_SPI_SRST; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); /* Disable AUTO_CS and deactivate all chip-selects */ a3700_spi_auto_cs_unset(a3700_spi); for (i = 0; i < master->num_chipselect; i++) a3700_spi_deactivate_cs(a3700_spi, i); /* Enable FIFO mode */ a3700_spi_fifo_mode_set(a3700_spi); /* Set SPI mode */ a3700_spi_mode_set(a3700_spi, master->mode_bits); /* Reset counters */ spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, 0); spireg_write(a3700_spi, A3700_SPI_IF_DIN_CNT_REG, 0); /* Mask the interrupts and clear cause bits */ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0); spireg_write(a3700_spi, A3700_SPI_INT_STAT_REG, ~0U); return ret; } static irqreturn_t a3700_spi_interrupt(int irq, void *dev_id) { struct spi_master *master = dev_id; struct a3700_spi *a3700_spi; u32 cause; a3700_spi = spi_master_get_devdata(master); /* Get interrupt causes */ cause = spireg_read(a3700_spi, A3700_SPI_INT_STAT_REG); if (!cause || !(a3700_spi->wait_mask & cause)) return IRQ_NONE; /* mask and acknowledge the SPI interrupts */ spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0); spireg_write(a3700_spi, A3700_SPI_INT_STAT_REG, cause); /* Wake up the transfer */ if (a3700_spi->wait_mask & cause) complete(&a3700_spi->done); return IRQ_HANDLED; } static bool a3700_spi_wait_completion(struct spi_device *spi) { struct a3700_spi *a3700_spi; unsigned int timeout; unsigned int ctrl_reg; unsigned long timeout_jiffies; a3700_spi = spi_master_get_devdata(spi->master); /* SPI interrupt is edge-triggered, which means an interrupt will * be generated only when detecting a specific status bit changed * from '0' to '1'. So when we start waiting for a interrupt, we * need to check status bit in control reg first, if it is already 1, * then we do not need to wait for interrupt */ ctrl_reg = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); if (a3700_spi->wait_mask & ctrl_reg) return true; reinit_completion(&a3700_spi->done); spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, a3700_spi->wait_mask); timeout_jiffies = msecs_to_jiffies(A3700_SPI_TIMEOUT); timeout = wait_for_completion_timeout(&a3700_spi->done, timeout_jiffies); a3700_spi->wait_mask = 0; if (timeout) return true; /* there might be the case that right after we checked the * status bits in this routine and before start to wait for * interrupt by wait_for_completion_timeout, the interrupt * happens, to avoid missing it we need to double check * status bits in control reg, if it is already 1, then * consider that we have the interrupt successfully and * return true. */ ctrl_reg = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); if (a3700_spi->wait_mask & ctrl_reg) return true; spireg_write(a3700_spi, A3700_SPI_INT_MASK_REG, 0); return true; } static bool a3700_spi_transfer_wait(struct spi_device *spi, unsigned int bit_mask) { struct a3700_spi *a3700_spi; a3700_spi = spi_master_get_devdata(spi->master); a3700_spi->wait_mask = bit_mask; return a3700_spi_wait_completion(spi); } static void a3700_spi_fifo_thres_set(struct a3700_spi *a3700_spi, unsigned int bytes) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~(A3700_SPI_FIFO_THRS_MASK << A3700_SPI_RFIFO_THRS_BIT); val |= (bytes - 1) << A3700_SPI_RFIFO_THRS_BIT; val &= ~(A3700_SPI_FIFO_THRS_MASK << A3700_SPI_WFIFO_THRS_BIT); val |= (7 - bytes) << A3700_SPI_WFIFO_THRS_BIT; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static void a3700_spi_transfer_setup(struct spi_device *spi, struct spi_transfer *xfer) { struct a3700_spi *a3700_spi; unsigned int byte_len; a3700_spi = spi_master_get_devdata(spi->master); a3700_spi_clock_set(a3700_spi, xfer->speed_hz, spi->mode); byte_len = xfer->bits_per_word >> 3; a3700_spi_fifo_thres_set(a3700_spi, byte_len); } static void a3700_spi_set_cs(struct spi_device *spi, bool enable) { struct a3700_spi *a3700_spi = spi_master_get_devdata(spi->master); if (!enable) a3700_spi_activate_cs(a3700_spi, spi->chip_select); else a3700_spi_deactivate_cs(a3700_spi, spi->chip_select); } static void a3700_spi_header_set(struct a3700_spi *a3700_spi) { u32 instr_cnt = 0, addr_cnt = 0, dummy_cnt = 0; u32 val = 0; /* Clear the header registers */ spireg_write(a3700_spi, A3700_SPI_IF_INST_REG, 0); spireg_write(a3700_spi, A3700_SPI_IF_ADDR_REG, 0); spireg_write(a3700_spi, A3700_SPI_IF_RMODE_REG, 0); /* Set header counters */ if (a3700_spi->tx_buf) { if (a3700_spi->buf_len <= a3700_spi->instr_cnt) { instr_cnt = a3700_spi->buf_len; } else if (a3700_spi->buf_len <= (a3700_spi->instr_cnt + a3700_spi->addr_cnt)) { instr_cnt = a3700_spi->instr_cnt; addr_cnt = a3700_spi->buf_len - instr_cnt; } else if (a3700_spi->buf_len <= a3700_spi->hdr_cnt) { instr_cnt = a3700_spi->instr_cnt; addr_cnt = a3700_spi->addr_cnt; /* Need to handle the normal write case with 1 byte * data */ if (!a3700_spi->tx_buf[instr_cnt + addr_cnt]) dummy_cnt = a3700_spi->buf_len - instr_cnt - addr_cnt; } val |= ((instr_cnt & A3700_SPI_INSTR_CNT_MASK) << A3700_SPI_INSTR_CNT_BIT); val |= ((addr_cnt & A3700_SPI_ADDR_CNT_MASK) << A3700_SPI_ADDR_CNT_BIT); val |= ((dummy_cnt & A3700_SPI_DUMMY_CNT_MASK) << A3700_SPI_DUMMY_CNT_BIT); } spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, val); /* Update the buffer length to be transferred */ a3700_spi->buf_len -= (instr_cnt + addr_cnt + dummy_cnt); /* Set Instruction */ val = 0; while (instr_cnt--) { val = (val << 8) | a3700_spi->tx_buf[0]; a3700_spi->tx_buf++; } spireg_write(a3700_spi, A3700_SPI_IF_INST_REG, val); /* Set Address */ val = 0; while (addr_cnt--) { val = (val << 8) | a3700_spi->tx_buf[0]; a3700_spi->tx_buf++; } spireg_write(a3700_spi, A3700_SPI_IF_ADDR_REG, val); } static int a3700_is_wfifo_full(struct a3700_spi *a3700_spi) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); return (val & A3700_SPI_WFIFO_FULL); } static int a3700_spi_fifo_write(struct a3700_spi *a3700_spi) { u32 val; int i = 0; while (!a3700_is_wfifo_full(a3700_spi) && a3700_spi->buf_len) { val = 0; if (a3700_spi->buf_len >= 4) { val = cpu_to_le32(*(u32 *)a3700_spi->tx_buf); spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val); a3700_spi->buf_len -= 4; a3700_spi->tx_buf += 4; } else { /* * If the remained buffer length is less than 4-bytes, * we should pad the write buffer with all ones. So that * it avoids overwrite the unexpected bytes following * the last one. */ val = GENMASK(31, 0); while (a3700_spi->buf_len) { val &= ~(0xff << (8 * i)); val |= *a3700_spi->tx_buf++ << (8 * i); i++; a3700_spi->buf_len--; spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val); } break; } } return 0; } static int a3700_is_rfifo_empty(struct a3700_spi *a3700_spi) { u32 val = spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG); return (val & A3700_SPI_RFIFO_EMPTY); } static int a3700_spi_fifo_read(struct a3700_spi *a3700_spi) { u32 val; while (!a3700_is_rfifo_empty(a3700_spi) && a3700_spi->buf_len) { val = spireg_read(a3700_spi, A3700_SPI_DATA_IN_REG); if (a3700_spi->buf_len >= 4) { u32 data = le32_to_cpu(val); memcpy(a3700_spi->rx_buf, &data, 4); a3700_spi->buf_len -= 4; a3700_spi->rx_buf += 4; } else { /* * When remain bytes is not larger than 4, we should * avoid memory overwriting and just write the left rx * buffer bytes. */ while (a3700_spi->buf_len) { *a3700_spi->rx_buf = val & 0xff; val >>= 8; a3700_spi->buf_len--; a3700_spi->rx_buf++; } } } return 0; } static void a3700_spi_transfer_abort_fifo(struct a3700_spi *a3700_spi) { int timeout = A3700_SPI_TIMEOUT; u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= A3700_SPI_XFER_STOP; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); while (--timeout) { val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (!(val & A3700_SPI_XFER_START)) break; udelay(1); } a3700_spi_fifo_flush(a3700_spi); val &= ~A3700_SPI_XFER_STOP; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } static int a3700_spi_prepare_message(struct spi_master *master, struct spi_message *message) { struct a3700_spi *a3700_spi = spi_master_get_devdata(master); struct spi_device *spi = message->spi; int ret; ret = clk_enable(a3700_spi->clk); if (ret) { dev_err(&spi->dev, "failed to enable clk with error %d\n", ret); return ret; } /* Flush the FIFOs */ ret = a3700_spi_fifo_flush(a3700_spi); if (ret) return ret; a3700_spi_bytelen_set(a3700_spi, 4); return 0; } static int a3700_spi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { struct a3700_spi *a3700_spi = spi_master_get_devdata(master); int ret = 0, timeout = A3700_SPI_TIMEOUT; unsigned int nbits = 0; u32 val; a3700_spi_transfer_setup(spi, xfer); a3700_spi->tx_buf = xfer->tx_buf; a3700_spi->rx_buf = xfer->rx_buf; a3700_spi->buf_len = xfer->len; /* SPI transfer headers */ a3700_spi_header_set(a3700_spi); if (xfer->tx_buf) nbits = xfer->tx_nbits; else if (xfer->rx_buf) nbits = xfer->rx_nbits; a3700_spi_pin_mode_set(a3700_spi, nbits); if (xfer->rx_buf) { /* Set read data length */ spireg_write(a3700_spi, A3700_SPI_IF_DIN_CNT_REG, a3700_spi->buf_len); /* Start READ transfer */ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val &= ~A3700_SPI_RW_EN; val |= A3700_SPI_XFER_START; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } else if (xfer->tx_buf) { /* Start Write transfer */ val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= (A3700_SPI_XFER_START | A3700_SPI_RW_EN); spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); /* * If there are data to be written to the SPI device, xmit_data * flag is set true; otherwise the instruction in SPI_INSTR does * not require data to be written to the SPI device, then * xmit_data flag is set false. */ a3700_spi->xmit_data = (a3700_spi->buf_len != 0); } while (a3700_spi->buf_len) { if (a3700_spi->tx_buf) { /* Wait wfifo ready */ if (!a3700_spi_transfer_wait(spi, A3700_SPI_WFIFO_RDY)) { dev_err(&spi->dev, "wait wfifo ready timed out\n"); ret = -ETIMEDOUT; goto error; } /* Fill up the wfifo */ ret = a3700_spi_fifo_write(a3700_spi); if (ret) goto error; } else if (a3700_spi->rx_buf) { /* Wait rfifo ready */ if (!a3700_spi_transfer_wait(spi, A3700_SPI_RFIFO_RDY)) { dev_err(&spi->dev, "wait rfifo ready timed out\n"); ret = -ETIMEDOUT; goto error; } /* Drain out the rfifo */ ret = a3700_spi_fifo_read(a3700_spi); if (ret) goto error; } } /* * Stop a write transfer in fifo mode: * - wait all the bytes in wfifo to be shifted out * - set XFER_STOP bit * - wait XFER_START bit clear * - clear XFER_STOP bit * Stop a read transfer in fifo mode: * - the hardware is to reset the XFER_START bit * after the number of bytes indicated in DIN_CNT * register * - just wait XFER_START bit clear */ if (a3700_spi->tx_buf) { if (a3700_spi->xmit_data) { /* * If there are data written to the SPI device, wait * until SPI_WFIFO_EMPTY is 1 to wait for all data to * transfer out of write FIFO. */ if (!a3700_spi_transfer_wait(spi, A3700_SPI_WFIFO_EMPTY)) { dev_err(&spi->dev, "wait wfifo empty timed out\n"); return -ETIMEDOUT; } } else { /* * If the instruction in SPI_INSTR does not require data * to be written to the SPI device, wait until SPI_RDY * is 1 for the SPI interface to be in idle. */ if (!a3700_spi_transfer_wait(spi, A3700_SPI_XFER_RDY)) { dev_err(&spi->dev, "wait xfer ready timed out\n"); return -ETIMEDOUT; } } val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); val |= A3700_SPI_XFER_STOP; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); } while (--timeout) { val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (!(val & A3700_SPI_XFER_START)) break; udelay(1); } if (timeout == 0) { dev_err(&spi->dev, "wait transfer start clear timed out\n"); ret = -ETIMEDOUT; goto error; } val &= ~A3700_SPI_XFER_STOP; spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val); goto out; error: a3700_spi_transfer_abort_fifo(a3700_spi); out: spi_finalize_current_transfer(master); return ret; } static int a3700_spi_unprepare_message(struct spi_master *master, struct spi_message *message) { struct a3700_spi *a3700_spi = spi_master_get_devdata(master); clk_disable(a3700_spi->clk); return 0; } static const struct of_device_id a3700_spi_dt_ids[] = { { .compatible = "marvell,armada-3700-spi", .data = NULL }, {}, }; MODULE_DEVICE_TABLE(of, a3700_spi_dt_ids); static int a3700_spi_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *of_node = dev->of_node; struct resource *res; struct spi_master *master; struct a3700_spi *spi; u32 num_cs = 0; int ret = 0; master = spi_alloc_master(dev, sizeof(*spi)); if (!master) { dev_err(dev, "master allocation failed\n"); ret = -ENOMEM; goto out; } if (of_property_read_u32(of_node, "num-cs", &num_cs)) { dev_err(dev, "could not find num-cs\n"); ret = -ENXIO; goto error; } master->bus_num = pdev->id; master->dev.of_node = of_node; master->mode_bits = SPI_MODE_3; master->num_chipselect = num_cs; master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(32); master->prepare_message = a3700_spi_prepare_message; master->transfer_one = a3700_spi_transfer_one; master->unprepare_message = a3700_spi_unprepare_message; master->set_cs = a3700_spi_set_cs; master->flags = SPI_MASTER_HALF_DUPLEX; master->mode_bits |= (SPI_RX_DUAL | SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_QUAD); platform_set_drvdata(pdev, master); spi = spi_master_get_devdata(master); memset(spi, 0, sizeof(struct a3700_spi)); spi->master = master; spi->instr_cnt = A3700_INSTR_CNT; spi->addr_cnt = A3700_ADDR_CNT; spi->hdr_cnt = A3700_INSTR_CNT + A3700_ADDR_CNT + A3700_DUMMY_CNT; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); spi->base = devm_ioremap_resource(dev, res); if (IS_ERR(spi->base)) { ret = PTR_ERR(spi->base); goto error; } spi->irq = platform_get_irq(pdev, 0); if (spi->irq < 0) { dev_err(dev, "could not get irq: %d\n", spi->irq); ret = -ENXIO; goto error; } init_completion(&spi->done); spi->clk = devm_clk_get(dev, NULL); if (IS_ERR(spi->clk)) { dev_err(dev, "could not find clk: %ld\n", PTR_ERR(spi->clk)); goto error; } ret = clk_prepare(spi->clk); if (ret) { dev_err(dev, "could not prepare clk: %d\n", ret); goto error; } ret = a3700_spi_init(spi); if (ret) goto error_clk; ret = devm_request_irq(dev, spi->irq, a3700_spi_interrupt, 0, dev_name(dev), master); if (ret) { dev_err(dev, "could not request IRQ: %d\n", ret); goto error_clk; } ret = devm_spi_register_master(dev, master); if (ret) { dev_err(dev, "Failed to register master\n"); goto error_clk; } return 0; error_clk: clk_disable_unprepare(spi->clk); error: spi_master_put(master); out: return ret; } static int a3700_spi_remove(struct platform_device *pdev) { struct spi_master *master = platform_get_drvdata(pdev); struct a3700_spi *spi = spi_master_get_devdata(master); clk_unprepare(spi->clk); spi_master_put(master); return 0; } static struct platform_driver a3700_spi_driver = { .driver = { .name = DRIVER_NAME, .owner = THIS_MODULE, .of_match_table = of_match_ptr(a3700_spi_dt_ids), }, .probe = a3700_spi_probe, .remove = a3700_spi_remove, }; module_platform_driver(a3700_spi_driver); MODULE_DESCRIPTION("Armada-3700 SPI driver"); MODULE_AUTHOR("Wilson Ding "); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DRIVER_NAME);