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drivers/spi/spi-armada-3700.c
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/* * 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> * * 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 <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/of_irq.h> #include <linux/of_device.h> #include <linux/pinctrl/consumer.h> #include <linux/spi/spi.h> #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) |
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#define A3700_SPI_CLK_EVEN_OFFS (0x10) |
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#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) |
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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; |
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}; 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, |
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unsigned int pin_mode, bool receiving) |
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{ 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) { |
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case SPI_NBITS_SINGLE: |
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break; |
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case SPI_NBITS_DUAL: |
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val |= A3700_SPI_DATA_PIN0; break; |
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case SPI_NBITS_QUAD: |
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val |= A3700_SPI_DATA_PIN1; |
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/* RX during address reception uses 4-pin */ if (receiving) val |= A3700_SPI_ADDR_PIN; |
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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); |
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/* 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); |
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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 */ |
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complete(&a3700_spi->done); |
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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); |
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/* Timeout was reached */ return false; |
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} 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, |
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struct spi_transfer *xfer) |
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{ 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) { |
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unsigned int addr_cnt; |
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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); |
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spireg_write(a3700_spi, A3700_SPI_IF_HDR_CNT_REG, 0); |
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/* Set header counters */ if (a3700_spi->tx_buf) { |
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/* * 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); |
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} |
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} |
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} 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; |
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while (!a3700_is_wfifo_full(a3700_spi) && a3700_spi->buf_len) { |
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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; |
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} 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); |
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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 ", 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; |
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if (xfer->tx_buf) nbits = xfer->tx_nbits; else if (xfer->rx_buf) nbits = xfer->rx_nbits; |
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a3700_spi_pin_mode_set(a3700_spi, nbits, xfer->rx_buf ? true : false); |
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/* 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); |
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if (xfer->rx_buf) { |
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/* 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); |
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625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 |
/* 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 "); 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 "); 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 "); return -ETIMEDOUT; } |
6fd6fd68c spi: armada-3700:... |
705 706 707 708 709 710 |
} if (!a3700_spi_transfer_wait(spi, A3700_SPI_XFER_RDY)) { dev_err(&spi->dev, "wait xfer ready timed out "); return -ETIMEDOUT; |
5762ab71e spi: Add support ... |
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} 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 "); 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; |
f6f0083cc spi: armada-3700:... |
769 |
int irq, ret = 0; |
5762ab71e spi: Add support ... |
770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 |
master = spi_alloc_master(dev, sizeof(*spi)); if (!master) { dev_err(dev, "master allocation failed "); ret = -ENOMEM; goto out; } if (of_property_read_u32(of_node, "num-cs", &num_cs)) { dev_err(dev, "could not find num-cs "); 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; |
42cd4ed88 spi: armada-3700:... |
796 |
master->mode_bits |= (SPI_RX_DUAL | SPI_TX_DUAL | |
5762ab71e spi: Add support ... |
797 798 799 800 801 802 803 804 |
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; |
5762ab71e spi: Add support ... |
805 806 807 808 809 810 811 |
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; } |
f6f0083cc spi: armada-3700:... |
812 813 814 815 |
irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_err(dev, "could not get irq: %d ", irq); |
5762ab71e spi: Add support ... |
816 817 818 |
ret = -ENXIO; goto error; } |
f6f0083cc spi: armada-3700:... |
819 |
spi->irq = irq; |
5762ab71e spi: Add support ... |
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init_completion(&spi->done); spi->clk = devm_clk_get(dev, NULL); if (IS_ERR(spi->clk)) { dev_err(dev, "could not find clk: %ld ", PTR_ERR(spi->clk)); goto error; } ret = clk_prepare(spi->clk); if (ret) { dev_err(dev, "could not prepare clk: %d ", 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 ", ret); goto error_clk; } ret = devm_spi_register_master(dev, master); if (ret) { dev_err(dev, "Failed to register master "); 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); |
5762ab71e spi: Add support ... |
872 873 874 875 876 877 878 |
return 0; } static struct platform_driver a3700_spi_driver = { .driver = { .name = DRIVER_NAME, |
5762ab71e spi: Add support ... |
879 880 881 882 883 884 885 886 887 888 889 890 |
.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 <dingwei@marvell.com>"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DRIVER_NAME); |