| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Romain Perier | 3089 | 86.92% | 2 | 8.33% |
| Maxime Chevallier | 304 | 8.55% | 9 | 37.50% |
| Yang Yingliang | 71 | 2.00% | 1 | 4.17% |
| Zachary Zhang | 27 | 0.76% | 1 | 4.17% |
| Miquel Raynal | 20 | 0.56% | 1 | 4.17% |
| Noam | 10 | 0.28% | 1 | 4.17% |
| Herve Codina via Alsa-devel | 10 | 0.28% | 1 | 4.17% |
| Colin Ian King | 8 | 0.23% | 1 | 4.17% |
| Wolfram Sang | 4 | 0.11% | 1 | 4.17% |
| Yue haibing | 3 | 0.08% | 1 | 4.17% |
| Li Zetao | 3 | 0.08% | 1 | 4.17% |
| Thomas Gleixner | 2 | 0.06% | 1 | 4.17% |
| Dan Carpenter | 1 | 0.03% | 1 | 4.17% |
| Rob Herring | 1 | 0.03% | 1 | 4.17% |
| Jason Yan | 1 | 0.03% | 1 | 4.17% |
| Total | 3554 | 24 |
// SPDX-License-Identifier: GPL-2.0-only /* * Marvell Armada-3700 SPI controller driver * * Copyright (C) 2016 Marvell Ltd. * * Author: Wilson Ding <dingwei@marvell.com> * Author: Romain Perier <romain.perier@free-electrons.com> */ #include <linux/clk.h> #include <linux/completion.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pinctrl/consumer.h> #include <linux/spi/spi.h> #define DRIVER_NAME "armada_3700_spi" #define A3700_SPI_MAX_SPEED_HZ 100000000 #define A3700_SPI_MAX_PRESCALE 30 #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_CLK_EVEN_OFFS (0x10) #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) struct a3700_spi { struct spi_controller *host; 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; }; 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, bool receiving) { 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 SPI_NBITS_SINGLE: break; case SPI_NBITS_DUAL: val |= A3700_SPI_DATA_PIN0; break; case SPI_NBITS_QUAD: val |= A3700_SPI_DATA_PIN1; /* RX during address reception uses 4-pin */ if (receiving) val |= A3700_SPI_ADDR_PIN; break; default: dev_err(&a3700_spi->host->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, bool enable) { u32 val; val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG); if (enable) val |= A3700_SPI_FIFO_MODE; else 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) { u32 val; u32 prescale; prescale = DIV_ROUND_UP(clk_get_rate(a3700_spi->clk), speed_hz); /* For prescaler values over 15, we can only set it by steps of 2. * Starting from A3700_SPI_CLK_EVEN_OFFS, we set values from 0 up to * 30. We only use this range from 16 to 30. */ if (prescale > 15) prescale = A3700_SPI_CLK_EVEN_OFFS + DIV_ROUND_UP(prescale, 2); 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); } } 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 void a3700_spi_init(struct a3700_spi *a3700_spi) { struct spi_controller *host = a3700_spi->host; u32 val; int i; /* 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 < host->num_chipselect; i++) a3700_spi_deactivate_cs(a3700_spi, i); /* Enable FIFO mode */ a3700_spi_fifo_mode_set(a3700_spi, true); /* Set SPI mode */ a3700_spi_mode_set(a3700_spi, host->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); } static irqreturn_t a3700_spi_interrupt(int irq, void *dev_id) { struct spi_controller *host = dev_id; struct a3700_spi *a3700_spi; u32 cause; a3700_spi = spi_controller_get_devdata(host); /* 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 */ complete(&a3700_spi->done); return IRQ_HANDLED; } static bool a3700_spi_wait_completion(struct spi_device *spi) { struct a3700_spi *a3700_spi; unsigned long time_left; unsigned int ctrl_reg; unsigned long timeout_jiffies; a3700_spi = spi_controller_get_devdata(spi->controller); /* 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); time_left = wait_for_completion_timeout(&a3700_spi->done, timeout_jiffies); a3700_spi->wait_mask = 0; if (time_left) 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); /* Timeout was reached */ return false; } static bool a3700_spi_transfer_wait(struct spi_device *spi, unsigned int bit_mask) { struct a3700_spi *a3700_spi; a3700_spi = spi_controller_get_devdata(spi->controller); 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; a3700_spi = spi_controller_get_devdata(spi->controller); a3700_spi_clock_set(a3700_spi, xfer->speed_hz); /* Use 4 bytes long transfers. Each transfer method has its way to deal * with the remaining bytes for non 4-bytes aligned transfers. */ a3700_spi_bytelen_set(a3700_spi, 4); /* Initialize the working buffers */ a3700_spi->tx_buf = xfer->tx_buf; a3700_spi->rx_buf = xfer->rx_buf; a3700_spi->buf_len = xfer->len; } static void a3700_spi_set_cs(struct spi_device *spi, bool enable) { struct a3700_spi *a3700_spi = spi_controller_get_devdata(spi->controller); if (!enable) a3700_spi_activate_cs(a3700_spi, spi_get_chipselect(spi, 0)); else a3700_spi_deactivate_cs(a3700_spi, spi_get_chipselect(spi, 0)); } static void a3700_spi_header_set(struct a3700_spi *a3700_spi) { unsigned int addr_cnt; 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); spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, 0); /* Set header counters */ if (a3700_spi->tx_buf) { /* * when tx data is not 4 bytes aligned, there will be unexpected * bytes out of SPI output register, since it always shifts out * as whole 4 bytes. This might cause incorrect transaction with * some devices. To avoid that, use SPI header count feature to * transfer up to 3 bytes of data first, and then make the rest * of data 4-byte aligned. */ addr_cnt = a3700_spi->buf_len % 4; if (addr_cnt) { val = (addr_cnt & A3700_SPI_ADDR_CNT_MASK) << A3700_SPI_ADDR_CNT_BIT; spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, val); /* Update the buffer length to be transferred */ a3700_spi->buf_len -= addr_cnt; /* transfer 1~3 bytes through address count */ 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; while (!a3700_is_wfifo_full(a3700_spi) && a3700_spi->buf_len) { val = *(u32 *)a3700_spi->tx_buf; spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, cpu_to_le32(val)); a3700_spi->buf_len -= 4; a3700_spi->tx_buf += 4; } 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) { val = le32_to_cpu(val); memcpy(a3700_spi->rx_buf, &val, 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_controller *host, struct spi_message *message) { struct a3700_spi *a3700_spi = spi_controller_get_devdata(host); 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_mode_set(a3700_spi, spi->mode); return 0; } static int a3700_spi_transfer_one_fifo(struct spi_controller *host, struct spi_device *spi, struct spi_transfer *xfer) { struct a3700_spi *a3700_spi = spi_controller_get_devdata(host); int ret = 0, timeout = A3700_SPI_TIMEOUT; unsigned int nbits = 0, byte_len; u32 val; /* Make sure we use FIFO mode */ a3700_spi_fifo_mode_set(a3700_spi, true); /* Configure FIFO thresholds */ byte_len = xfer->bits_per_word >> 3; a3700_spi_fifo_thres_set(a3700_spi, byte_len); 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, xfer->rx_buf ? true : false); /* Flush the FIFOs */ a3700_spi_fifo_flush(a3700_spi); /* Transfer first bytes of data when buffer is not 4-byte aligned */ a3700_spi_header_set(a3700_spi); if (xfer->rx_buf) { /* Clear WFIFO, since it's last 2 bytes are shifted out during * a read operation */ spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, 0); /* 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; } } 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(host); return ret; } static int a3700_spi_transfer_one_full_duplex(struct spi_controller *host, struct spi_device *spi, struct spi_transfer *xfer) { struct a3700_spi *a3700_spi = spi_controller_get_devdata(host); u32 val; /* Disable FIFO mode */ a3700_spi_fifo_mode_set(a3700_spi, false); while (a3700_spi->buf_len) { /* When we have less than 4 bytes to transfer, switch to 1 byte * mode. This is reset after each transfer */ if (a3700_spi->buf_len < 4) a3700_spi_bytelen_set(a3700_spi, 1); if (a3700_spi->byte_len == 1) val = *a3700_spi->tx_buf; else val = *(u32 *)a3700_spi->tx_buf; spireg_write(a3700_spi, A3700_SPI_DATA_OUT_REG, val); /* Wait for all the data to be shifted in / out */ while (!(spireg_read(a3700_spi, A3700_SPI_IF_CTRL_REG) & A3700_SPI_XFER_DONE)) cpu_relax(); val = spireg_read(a3700_spi, A3700_SPI_DATA_IN_REG); memcpy(a3700_spi->rx_buf, &val, a3700_spi->byte_len); a3700_spi->buf_len -= a3700_spi->byte_len; a3700_spi->tx_buf += a3700_spi->byte_len; a3700_spi->rx_buf += a3700_spi->byte_len; } spi_finalize_current_transfer(host); return 0; } static int a3700_spi_transfer_one(struct spi_controller *host, struct spi_device *spi, struct spi_transfer *xfer) { a3700_spi_transfer_setup(spi, xfer); if (xfer->tx_buf && xfer->rx_buf) return a3700_spi_transfer_one_full_duplex(host, spi, xfer); return a3700_spi_transfer_one_fifo(host, spi, xfer); } static int a3700_spi_unprepare_message(struct spi_controller *host, struct spi_message *message) { struct a3700_spi *a3700_spi = spi_controller_get_devdata(host); 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 spi_controller *host; struct a3700_spi *spi; u32 num_cs = 0; int irq, ret = 0; host = spi_alloc_host(dev, sizeof(*spi)); if (!host) { dev_err(dev, "host 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; } host->bus_num = pdev->id; host->dev.of_node = of_node; host->mode_bits = SPI_MODE_3; host->num_chipselect = num_cs; host->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(32); host->prepare_message = a3700_spi_prepare_message; host->transfer_one = a3700_spi_transfer_one; host->unprepare_message = a3700_spi_unprepare_message; host->set_cs = a3700_spi_set_cs; host->mode_bits |= (SPI_RX_DUAL | SPI_TX_DUAL | SPI_RX_QUAD | SPI_TX_QUAD); platform_set_drvdata(pdev, host); spi = spi_controller_get_devdata(host); spi->host = host; spi->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(spi->base)) { ret = PTR_ERR(spi->base); goto error; } irq = platform_get_irq(pdev, 0); if (irq < 0) { ret = -ENXIO; goto error; } spi->irq = irq; init_completion(&spi->done); spi->clk = devm_clk_get_prepared(dev, NULL); if (IS_ERR(spi->clk)) { dev_err(dev, "could not find clk: %ld\n", PTR_ERR(spi->clk)); goto error; } host->max_speed_hz = min_t(unsigned long, A3700_SPI_MAX_SPEED_HZ, clk_get_rate(spi->clk)); host->min_speed_hz = DIV_ROUND_UP(clk_get_rate(spi->clk), A3700_SPI_MAX_PRESCALE); a3700_spi_init(spi); ret = devm_request_irq(dev, spi->irq, a3700_spi_interrupt, 0, dev_name(dev), host); if (ret) { dev_err(dev, "could not request IRQ: %d\n", ret); goto error; } ret = devm_spi_register_controller(dev, host); if (ret) { dev_err(dev, "Failed to register host\n"); goto error; } return 0; error: spi_controller_put(host); out: return ret; } static struct platform_driver a3700_spi_driver = { .driver = { .name = DRIVER_NAME, .of_match_table = of_match_ptr(a3700_spi_dt_ids), }, .probe = a3700_spi_probe, }; module_platform_driver(a3700_spi_driver); MODULE_DESCRIPTION("Armada-3700 SPI driver"); MODULE_AUTHOR("Wilson Ding <dingwei@marvell.com>"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DRIVER_NAME);
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