| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (C) 2018 Spreadtrum Communications Inc. |
| |
| #include <linux/clk.h> |
| #include <linux/dmaengine.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/dma/sprd-dma.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/iopoll.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/of_device.h> |
| #include <linux/of_dma.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/spi/spi.h> |
| |
| #define SPRD_SPI_TXD 0x0 |
| #define SPRD_SPI_CLKD 0x4 |
| #define SPRD_SPI_CTL0 0x8 |
| #define SPRD_SPI_CTL1 0xc |
| #define SPRD_SPI_CTL2 0x10 |
| #define SPRD_SPI_CTL3 0x14 |
| #define SPRD_SPI_CTL4 0x18 |
| #define SPRD_SPI_CTL5 0x1c |
| #define SPRD_SPI_INT_EN 0x20 |
| #define SPRD_SPI_INT_CLR 0x24 |
| #define SPRD_SPI_INT_RAW_STS 0x28 |
| #define SPRD_SPI_INT_MASK_STS 0x2c |
| #define SPRD_SPI_STS1 0x30 |
| #define SPRD_SPI_STS2 0x34 |
| #define SPRD_SPI_DSP_WAIT 0x38 |
| #define SPRD_SPI_STS3 0x3c |
| #define SPRD_SPI_CTL6 0x40 |
| #define SPRD_SPI_STS4 0x44 |
| #define SPRD_SPI_FIFO_RST 0x48 |
| #define SPRD_SPI_CTL7 0x4c |
| #define SPRD_SPI_STS5 0x50 |
| #define SPRD_SPI_CTL8 0x54 |
| #define SPRD_SPI_CTL9 0x58 |
| #define SPRD_SPI_CTL10 0x5c |
| #define SPRD_SPI_CTL11 0x60 |
| #define SPRD_SPI_CTL12 0x64 |
| #define SPRD_SPI_STS6 0x68 |
| #define SPRD_SPI_STS7 0x6c |
| #define SPRD_SPI_STS8 0x70 |
| #define SPRD_SPI_STS9 0x74 |
| |
| /* Bits & mask definition for register CTL0 */ |
| #define SPRD_SPI_SCK_REV BIT(13) |
| #define SPRD_SPI_NG_TX BIT(1) |
| #define SPRD_SPI_NG_RX BIT(0) |
| #define SPRD_SPI_CHNL_LEN_MASK GENMASK(4, 0) |
| #define SPRD_SPI_CSN_MASK GENMASK(11, 8) |
| #define SPRD_SPI_CS0_VALID BIT(8) |
| |
| /* Bits & mask definition for register SPI_INT_EN */ |
| #define SPRD_SPI_TX_END_INT_EN BIT(8) |
| #define SPRD_SPI_RX_END_INT_EN BIT(9) |
| |
| /* Bits & mask definition for register SPI_INT_RAW_STS */ |
| #define SPRD_SPI_TX_END_RAW BIT(8) |
| #define SPRD_SPI_RX_END_RAW BIT(9) |
| |
| /* Bits & mask definition for register SPI_INT_CLR */ |
| #define SPRD_SPI_TX_END_CLR BIT(8) |
| #define SPRD_SPI_RX_END_CLR BIT(9) |
| |
| /* Bits & mask definition for register INT_MASK_STS */ |
| #define SPRD_SPI_MASK_RX_END BIT(9) |
| #define SPRD_SPI_MASK_TX_END BIT(8) |
| |
| /* Bits & mask definition for register STS2 */ |
| #define SPRD_SPI_TX_BUSY BIT(8) |
| |
| /* Bits & mask definition for register CTL1 */ |
| #define SPRD_SPI_RX_MODE BIT(12) |
| #define SPRD_SPI_TX_MODE BIT(13) |
| #define SPRD_SPI_RTX_MD_MASK GENMASK(13, 12) |
| |
| /* Bits & mask definition for register CTL2 */ |
| #define SPRD_SPI_DMA_EN BIT(6) |
| |
| /* Bits & mask definition for register CTL4 */ |
| #define SPRD_SPI_START_RX BIT(9) |
| #define SPRD_SPI_ONLY_RECV_MASK GENMASK(8, 0) |
| |
| /* Bits & mask definition for register SPI_INT_CLR */ |
| #define SPRD_SPI_RX_END_INT_CLR BIT(9) |
| #define SPRD_SPI_TX_END_INT_CLR BIT(8) |
| |
| /* Bits & mask definition for register SPI_INT_RAW */ |
| #define SPRD_SPI_RX_END_IRQ BIT(9) |
| #define SPRD_SPI_TX_END_IRQ BIT(8) |
| |
| /* Bits & mask definition for register CTL12 */ |
| #define SPRD_SPI_SW_RX_REQ BIT(0) |
| #define SPRD_SPI_SW_TX_REQ BIT(1) |
| |
| /* Bits & mask definition for register CTL7 */ |
| #define SPRD_SPI_DATA_LINE2_EN BIT(15) |
| #define SPRD_SPI_MODE_MASK GENMASK(5, 3) |
| #define SPRD_SPI_MODE_OFFSET 3 |
| #define SPRD_SPI_3WIRE_MODE 4 |
| #define SPRD_SPI_4WIRE_MODE 0 |
| |
| /* Bits & mask definition for register CTL8 */ |
| #define SPRD_SPI_TX_MAX_LEN_MASK GENMASK(19, 0) |
| #define SPRD_SPI_TX_LEN_H_MASK GENMASK(3, 0) |
| #define SPRD_SPI_TX_LEN_H_OFFSET 16 |
| |
| /* Bits & mask definition for register CTL9 */ |
| #define SPRD_SPI_TX_LEN_L_MASK GENMASK(15, 0) |
| |
| /* Bits & mask definition for register CTL10 */ |
| #define SPRD_SPI_RX_MAX_LEN_MASK GENMASK(19, 0) |
| #define SPRD_SPI_RX_LEN_H_MASK GENMASK(3, 0) |
| #define SPRD_SPI_RX_LEN_H_OFFSET 16 |
| |
| /* Bits & mask definition for register CTL11 */ |
| #define SPRD_SPI_RX_LEN_L_MASK GENMASK(15, 0) |
| |
| /* Default & maximum word delay cycles */ |
| #define SPRD_SPI_MIN_DELAY_CYCLE 14 |
| #define SPRD_SPI_MAX_DELAY_CYCLE 130 |
| |
| #define SPRD_SPI_FIFO_SIZE 32 |
| #define SPRD_SPI_CHIP_CS_NUM 0x4 |
| #define SPRD_SPI_CHNL_LEN 2 |
| #define SPRD_SPI_DEFAULT_SOURCE 26000000 |
| #define SPRD_SPI_MAX_SPEED_HZ 48000000 |
| #define SPRD_SPI_AUTOSUSPEND_DELAY 100 |
| #define SPRD_SPI_DMA_STEP 8 |
| |
| enum sprd_spi_dma_channel { |
| SPRD_SPI_RX, |
| SPRD_SPI_TX, |
| SPRD_SPI_MAX, |
| }; |
| |
| struct sprd_spi_dma { |
| bool enable; |
| struct dma_chan *dma_chan[SPRD_SPI_MAX]; |
| enum dma_slave_buswidth width; |
| u32 fragmens_len; |
| u32 rx_len; |
| }; |
| |
| struct sprd_spi { |
| void __iomem *base; |
| phys_addr_t phy_base; |
| struct device *dev; |
| struct clk *clk; |
| int irq; |
| u32 src_clk; |
| u32 hw_mode; |
| u32 trans_len; |
| u32 trans_mode; |
| u32 word_delay; |
| u32 hw_speed_hz; |
| u32 len; |
| int status; |
| struct sprd_spi_dma dma; |
| struct completion xfer_completion; |
| const void *tx_buf; |
| void *rx_buf; |
| int (*read_bufs)(struct sprd_spi *ss, u32 len); |
| int (*write_bufs)(struct sprd_spi *ss, u32 len); |
| }; |
| |
| static u32 sprd_spi_transfer_max_timeout(struct sprd_spi *ss, |
| struct spi_transfer *t) |
| { |
| /* |
| * The time spent on transmission of the full FIFO data is the maximum |
| * SPI transmission time. |
| */ |
| u32 size = t->bits_per_word * SPRD_SPI_FIFO_SIZE; |
| u32 bit_time_us = DIV_ROUND_UP(USEC_PER_SEC, ss->hw_speed_hz); |
| u32 total_time_us = size * bit_time_us; |
| /* |
| * There is an interval between data and the data in our SPI hardware, |
| * so the total transmission time need add the interval time. |
| */ |
| u32 interval_cycle = SPRD_SPI_FIFO_SIZE * ss->word_delay; |
| u32 interval_time_us = DIV_ROUND_UP(interval_cycle * USEC_PER_SEC, |
| ss->src_clk); |
| |
| return total_time_us + interval_time_us; |
| } |
| |
| static int sprd_spi_wait_for_tx_end(struct sprd_spi *ss, struct spi_transfer *t) |
| { |
| u32 val, us; |
| int ret; |
| |
| us = sprd_spi_transfer_max_timeout(ss, t); |
| ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val, |
| val & SPRD_SPI_TX_END_IRQ, 0, us); |
| if (ret) { |
| dev_err(ss->dev, "SPI error, spi send timeout!\n"); |
| return ret; |
| } |
| |
| ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_STS2, val, |
| !(val & SPRD_SPI_TX_BUSY), 0, us); |
| if (ret) { |
| dev_err(ss->dev, "SPI error, spi busy timeout!\n"); |
| return ret; |
| } |
| |
| writel_relaxed(SPRD_SPI_TX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR); |
| |
| return 0; |
| } |
| |
| static int sprd_spi_wait_for_rx_end(struct sprd_spi *ss, struct spi_transfer *t) |
| { |
| u32 val, us; |
| int ret; |
| |
| us = sprd_spi_transfer_max_timeout(ss, t); |
| ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val, |
| val & SPRD_SPI_RX_END_IRQ, 0, us); |
| if (ret) { |
| dev_err(ss->dev, "SPI error, spi rx timeout!\n"); |
| return ret; |
| } |
| |
| writel_relaxed(SPRD_SPI_RX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR); |
| |
| return 0; |
| } |
| |
| static void sprd_spi_tx_req(struct sprd_spi *ss) |
| { |
| writel_relaxed(SPRD_SPI_SW_TX_REQ, ss->base + SPRD_SPI_CTL12); |
| } |
| |
| static void sprd_spi_rx_req(struct sprd_spi *ss) |
| { |
| writel_relaxed(SPRD_SPI_SW_RX_REQ, ss->base + SPRD_SPI_CTL12); |
| } |
| |
| static void sprd_spi_enter_idle(struct sprd_spi *ss) |
| { |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL1); |
| |
| val &= ~SPRD_SPI_RTX_MD_MASK; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL1); |
| } |
| |
| static void sprd_spi_set_transfer_bits(struct sprd_spi *ss, u32 bits) |
| { |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL0); |
| |
| /* Set the valid bits for every transaction */ |
| val &= ~(SPRD_SPI_CHNL_LEN_MASK << SPRD_SPI_CHNL_LEN); |
| val |= bits << SPRD_SPI_CHNL_LEN; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL0); |
| } |
| |
| static void sprd_spi_set_tx_length(struct sprd_spi *ss, u32 length) |
| { |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL8); |
| |
| length &= SPRD_SPI_TX_MAX_LEN_MASK; |
| val &= ~SPRD_SPI_TX_LEN_H_MASK; |
| val |= length >> SPRD_SPI_TX_LEN_H_OFFSET; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL8); |
| |
| val = length & SPRD_SPI_TX_LEN_L_MASK; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL9); |
| } |
| |
| static void sprd_spi_set_rx_length(struct sprd_spi *ss, u32 length) |
| { |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL10); |
| |
| length &= SPRD_SPI_RX_MAX_LEN_MASK; |
| val &= ~SPRD_SPI_RX_LEN_H_MASK; |
| val |= length >> SPRD_SPI_RX_LEN_H_OFFSET; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL10); |
| |
| val = length & SPRD_SPI_RX_LEN_L_MASK; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL11); |
| } |
| |
| static void sprd_spi_chipselect(struct spi_device *sdev, bool cs) |
| { |
| struct spi_controller *sctlr = sdev->controller; |
| struct sprd_spi *ss = spi_controller_get_devdata(sctlr); |
| u32 val; |
| |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL0); |
| /* The SPI controller will pull down CS pin if cs is 0 */ |
| if (!cs) { |
| val &= ~SPRD_SPI_CS0_VALID; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL0); |
| } else { |
| val |= SPRD_SPI_CSN_MASK; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL0); |
| } |
| } |
| |
| static int sprd_spi_write_only_receive(struct sprd_spi *ss, u32 len) |
| { |
| u32 val; |
| |
| /* Clear the start receive bit and reset receive data number */ |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL4); |
| val &= ~(SPRD_SPI_START_RX | SPRD_SPI_ONLY_RECV_MASK); |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL4); |
| |
| /* Set the receive data length */ |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL4); |
| val |= len & SPRD_SPI_ONLY_RECV_MASK; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL4); |
| |
| /* Trigger to receive data */ |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL4); |
| val |= SPRD_SPI_START_RX; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL4); |
| |
| return len; |
| } |
| |
| static int sprd_spi_write_bufs_u8(struct sprd_spi *ss, u32 len) |
| { |
| u8 *tx_p = (u8 *)ss->tx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| writeb_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); |
| |
| ss->tx_buf += i; |
| return i; |
| } |
| |
| static int sprd_spi_write_bufs_u16(struct sprd_spi *ss, u32 len) |
| { |
| u16 *tx_p = (u16 *)ss->tx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| writew_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); |
| |
| ss->tx_buf += i << 1; |
| return i << 1; |
| } |
| |
| static int sprd_spi_write_bufs_u32(struct sprd_spi *ss, u32 len) |
| { |
| u32 *tx_p = (u32 *)ss->tx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| writel_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD); |
| |
| ss->tx_buf += i << 2; |
| return i << 2; |
| } |
| |
| static int sprd_spi_read_bufs_u8(struct sprd_spi *ss, u32 len) |
| { |
| u8 *rx_p = (u8 *)ss->rx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| rx_p[i] = readb_relaxed(ss->base + SPRD_SPI_TXD); |
| |
| ss->rx_buf += i; |
| return i; |
| } |
| |
| static int sprd_spi_read_bufs_u16(struct sprd_spi *ss, u32 len) |
| { |
| u16 *rx_p = (u16 *)ss->rx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| rx_p[i] = readw_relaxed(ss->base + SPRD_SPI_TXD); |
| |
| ss->rx_buf += i << 1; |
| return i << 1; |
| } |
| |
| static int sprd_spi_read_bufs_u32(struct sprd_spi *ss, u32 len) |
| { |
| u32 *rx_p = (u32 *)ss->rx_buf; |
| int i; |
| |
| for (i = 0; i < len; i++) |
| rx_p[i] = readl_relaxed(ss->base + SPRD_SPI_TXD); |
| |
| ss->rx_buf += i << 2; |
| return i << 2; |
| } |
| |
| static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t) |
| { |
| struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller); |
| u32 trans_len = ss->trans_len, len; |
| int ret, write_size = 0, read_size = 0; |
| |
| while (trans_len) { |
| len = trans_len > SPRD_SPI_FIFO_SIZE ? SPRD_SPI_FIFO_SIZE : |
| trans_len; |
| if (ss->trans_mode & SPRD_SPI_TX_MODE) { |
| sprd_spi_set_tx_length(ss, len); |
| write_size += ss->write_bufs(ss, len); |
| |
| /* |
| * For our 3 wires mode or dual TX line mode, we need |
| * to request the controller to transfer. |
| */ |
| if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) |
| sprd_spi_tx_req(ss); |
| |
| ret = sprd_spi_wait_for_tx_end(ss, t); |
| } else { |
| sprd_spi_set_rx_length(ss, len); |
| |
| /* |
| * For our 3 wires mode or dual TX line mode, we need |
| * to request the controller to read. |
| */ |
| if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) |
| sprd_spi_rx_req(ss); |
| else |
| write_size += ss->write_bufs(ss, len); |
| |
| ret = sprd_spi_wait_for_rx_end(ss, t); |
| } |
| |
| if (ret) |
| goto complete; |
| |
| if (ss->trans_mode & SPRD_SPI_RX_MODE) |
| read_size += ss->read_bufs(ss, len); |
| |
| trans_len -= len; |
| } |
| |
| if (ss->trans_mode & SPRD_SPI_TX_MODE) |
| ret = write_size; |
| else |
| ret = read_size; |
| complete: |
| sprd_spi_enter_idle(ss); |
| |
| return ret; |
| } |
| |
| static void sprd_spi_irq_enable(struct sprd_spi *ss) |
| { |
| u32 val; |
| |
| /* Clear interrupt status before enabling interrupt. */ |
| writel_relaxed(SPRD_SPI_TX_END_CLR | SPRD_SPI_RX_END_CLR, |
| ss->base + SPRD_SPI_INT_CLR); |
| /* Enable SPI interrupt only in DMA mode. */ |
| val = readl_relaxed(ss->base + SPRD_SPI_INT_EN); |
| writel_relaxed(val | SPRD_SPI_TX_END_INT_EN | |
| SPRD_SPI_RX_END_INT_EN, |
| ss->base + SPRD_SPI_INT_EN); |
| } |
| |
| static void sprd_spi_irq_disable(struct sprd_spi *ss) |
| { |
| writel_relaxed(0, ss->base + SPRD_SPI_INT_EN); |
| } |
| |
| static void sprd_spi_dma_enable(struct sprd_spi *ss, bool enable) |
| { |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL2); |
| |
| if (enable) |
| val |= SPRD_SPI_DMA_EN; |
| else |
| val &= ~SPRD_SPI_DMA_EN; |
| |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL2); |
| } |
| |
| static int sprd_spi_dma_submit(struct dma_chan *dma_chan, |
| struct dma_slave_config *c, |
| struct sg_table *sg, |
| enum dma_transfer_direction dir) |
| { |
| struct dma_async_tx_descriptor *desc; |
| dma_cookie_t cookie; |
| unsigned long flags; |
| int ret; |
| |
| ret = dmaengine_slave_config(dma_chan, c); |
| if (ret < 0) |
| return ret; |
| |
| flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG, |
| SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT); |
| desc = dmaengine_prep_slave_sg(dma_chan, sg->sgl, sg->nents, dir, flags); |
| if (!desc) |
| return -ENODEV; |
| |
| cookie = dmaengine_submit(desc); |
| if (dma_submit_error(cookie)) |
| return dma_submit_error(cookie); |
| |
| dma_async_issue_pending(dma_chan); |
| |
| return 0; |
| } |
| |
| static int sprd_spi_dma_rx_config(struct sprd_spi *ss, struct spi_transfer *t) |
| { |
| struct dma_chan *dma_chan = ss->dma.dma_chan[SPRD_SPI_RX]; |
| struct dma_slave_config config = { |
| .src_addr = ss->phy_base, |
| .src_addr_width = ss->dma.width, |
| .dst_addr_width = ss->dma.width, |
| .dst_maxburst = ss->dma.fragmens_len, |
| }; |
| int ret; |
| |
| ret = sprd_spi_dma_submit(dma_chan, &config, &t->rx_sg, DMA_DEV_TO_MEM); |
| if (ret) |
| return ret; |
| |
| return ss->dma.rx_len; |
| } |
| |
| static int sprd_spi_dma_tx_config(struct sprd_spi *ss, struct spi_transfer *t) |
| { |
| struct dma_chan *dma_chan = ss->dma.dma_chan[SPRD_SPI_TX]; |
| struct dma_slave_config config = { |
| .dst_addr = ss->phy_base, |
| .src_addr_width = ss->dma.width, |
| .dst_addr_width = ss->dma.width, |
| .src_maxburst = ss->dma.fragmens_len, |
| }; |
| int ret; |
| |
| ret = sprd_spi_dma_submit(dma_chan, &config, &t->tx_sg, DMA_MEM_TO_DEV); |
| if (ret) |
| return ret; |
| |
| return t->len; |
| } |
| |
| static int sprd_spi_dma_request(struct sprd_spi *ss) |
| { |
| ss->dma.dma_chan[SPRD_SPI_RX] = dma_request_chan(ss->dev, "rx_chn"); |
| if (IS_ERR_OR_NULL(ss->dma.dma_chan[SPRD_SPI_RX])) { |
| if (PTR_ERR(ss->dma.dma_chan[SPRD_SPI_RX]) == -EPROBE_DEFER) |
| return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_RX]); |
| |
| dev_err(ss->dev, "request RX DMA channel failed!\n"); |
| return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_RX]); |
| } |
| |
| ss->dma.dma_chan[SPRD_SPI_TX] = dma_request_chan(ss->dev, "tx_chn"); |
| if (IS_ERR_OR_NULL(ss->dma.dma_chan[SPRD_SPI_TX])) { |
| if (PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]) == -EPROBE_DEFER) |
| return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]); |
| |
| dev_err(ss->dev, "request TX DMA channel failed!\n"); |
| dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]); |
| return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]); |
| } |
| |
| return 0; |
| } |
| |
| static void sprd_spi_dma_release(struct sprd_spi *ss) |
| { |
| if (ss->dma.dma_chan[SPRD_SPI_RX]) |
| dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]); |
| |
| if (ss->dma.dma_chan[SPRD_SPI_TX]) |
| dma_release_channel(ss->dma.dma_chan[SPRD_SPI_TX]); |
| } |
| |
| static int sprd_spi_dma_txrx_bufs(struct spi_device *sdev, |
| struct spi_transfer *t) |
| { |
| struct sprd_spi *ss = spi_master_get_devdata(sdev->master); |
| u32 trans_len = ss->trans_len; |
| int ret, write_size = 0; |
| |
| reinit_completion(&ss->xfer_completion); |
| sprd_spi_irq_enable(ss); |
| if (ss->trans_mode & SPRD_SPI_TX_MODE) { |
| write_size = sprd_spi_dma_tx_config(ss, t); |
| sprd_spi_set_tx_length(ss, trans_len); |
| |
| /* |
| * For our 3 wires mode or dual TX line mode, we need |
| * to request the controller to transfer. |
| */ |
| if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) |
| sprd_spi_tx_req(ss); |
| } else { |
| sprd_spi_set_rx_length(ss, trans_len); |
| |
| /* |
| * For our 3 wires mode or dual TX line mode, we need |
| * to request the controller to read. |
| */ |
| if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL) |
| sprd_spi_rx_req(ss); |
| else |
| write_size = ss->write_bufs(ss, trans_len); |
| } |
| |
| if (write_size < 0) { |
| ret = write_size; |
| dev_err(ss->dev, "failed to write, ret = %d\n", ret); |
| goto trans_complete; |
| } |
| |
| if (ss->trans_mode & SPRD_SPI_RX_MODE) { |
| /* |
| * Set up the DMA receive data length, which must be an |
| * integral multiple of fragment length. But when the length |
| * of received data is less than fragment length, DMA can be |
| * configured to receive data according to the actual length |
| * of received data. |
| */ |
| ss->dma.rx_len = t->len > ss->dma.fragmens_len ? |
| (t->len - t->len % ss->dma.fragmens_len) : |
| t->len; |
| ret = sprd_spi_dma_rx_config(ss, t); |
| if (ret < 0) { |
| dev_err(&sdev->dev, |
| "failed to configure rx DMA, ret = %d\n", ret); |
| goto trans_complete; |
| } |
| } |
| |
| sprd_spi_dma_enable(ss, true); |
| wait_for_completion(&(ss->xfer_completion)); |
| |
| if (ss->trans_mode & SPRD_SPI_TX_MODE) |
| ret = write_size; |
| else |
| ret = ss->dma.rx_len; |
| |
| trans_complete: |
| sprd_spi_dma_enable(ss, false); |
| sprd_spi_enter_idle(ss); |
| sprd_spi_irq_disable(ss); |
| |
| return ret; |
| } |
| |
| static void sprd_spi_set_speed(struct sprd_spi *ss, u32 speed_hz) |
| { |
| /* |
| * From SPI datasheet, the prescale calculation formula: |
| * prescale = SPI source clock / (2 * SPI_freq) - 1; |
| */ |
| u32 clk_div = DIV_ROUND_UP(ss->src_clk, speed_hz << 1) - 1; |
| |
| /* Save the real hardware speed */ |
| ss->hw_speed_hz = (ss->src_clk >> 1) / (clk_div + 1); |
| writel_relaxed(clk_div, ss->base + SPRD_SPI_CLKD); |
| } |
| |
| static int sprd_spi_init_hw(struct sprd_spi *ss, struct spi_transfer *t) |
| { |
| struct spi_delay *d = &t->word_delay; |
| u16 word_delay, interval; |
| u32 val; |
| |
| if (d->unit != SPI_DELAY_UNIT_SCK) |
| return -EINVAL; |
| |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL7); |
| val &= ~(SPRD_SPI_SCK_REV | SPRD_SPI_NG_TX | SPRD_SPI_NG_RX); |
| /* Set default chip selection, clock phase and clock polarity */ |
| val |= ss->hw_mode & SPI_CPHA ? SPRD_SPI_NG_RX : SPRD_SPI_NG_TX; |
| val |= ss->hw_mode & SPI_CPOL ? SPRD_SPI_SCK_REV : 0; |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL0); |
| |
| /* |
| * Set the intervals of two SPI frames, and the inteval calculation |
| * formula as below per datasheet: |
| * interval time (source clock cycles) = interval * 4 + 10. |
| */ |
| word_delay = clamp_t(u16, d->value, SPRD_SPI_MIN_DELAY_CYCLE, |
| SPRD_SPI_MAX_DELAY_CYCLE); |
| interval = DIV_ROUND_UP(word_delay - 10, 4); |
| ss->word_delay = interval * 4 + 10; |
| writel_relaxed(interval, ss->base + SPRD_SPI_CTL5); |
| |
| /* Reset SPI fifo */ |
| writel_relaxed(1, ss->base + SPRD_SPI_FIFO_RST); |
| writel_relaxed(0, ss->base + SPRD_SPI_FIFO_RST); |
| |
| /* Set SPI work mode */ |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL7); |
| val &= ~SPRD_SPI_MODE_MASK; |
| |
| if (ss->hw_mode & SPI_3WIRE) |
| val |= SPRD_SPI_3WIRE_MODE << SPRD_SPI_MODE_OFFSET; |
| else |
| val |= SPRD_SPI_4WIRE_MODE << SPRD_SPI_MODE_OFFSET; |
| |
| if (ss->hw_mode & SPI_TX_DUAL) |
| val |= SPRD_SPI_DATA_LINE2_EN; |
| else |
| val &= ~SPRD_SPI_DATA_LINE2_EN; |
| |
| writel_relaxed(val, ss->base + SPRD_SPI_CTL7); |
| |
| return 0; |
| } |
| |
| static int sprd_spi_setup_transfer(struct spi_device *sdev, |
| struct spi_transfer *t) |
| { |
| struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller); |
| u8 bits_per_word = t->bits_per_word; |
| u32 val, mode = 0; |
| int ret; |
| |
| ss->len = t->len; |
| ss->tx_buf = t->tx_buf; |
| ss->rx_buf = t->rx_buf; |
| |
| ss->hw_mode = sdev->mode; |
| ret = sprd_spi_init_hw(ss, t); |
| if (ret) |
| return ret; |
| |
| /* Set tansfer speed and valid bits */ |
| sprd_spi_set_speed(ss, t->speed_hz); |
| sprd_spi_set_transfer_bits(ss, bits_per_word); |
| |
| if (bits_per_word > 16) |
| bits_per_word = round_up(bits_per_word, 16); |
| else |
| bits_per_word = round_up(bits_per_word, 8); |
| |
| switch (bits_per_word) { |
| case 8: |
| ss->trans_len = t->len; |
| ss->read_bufs = sprd_spi_read_bufs_u8; |
| ss->write_bufs = sprd_spi_write_bufs_u8; |
| ss->dma.width = DMA_SLAVE_BUSWIDTH_1_BYTE; |
| ss->dma.fragmens_len = SPRD_SPI_DMA_STEP; |
| break; |
| case 16: |
| ss->trans_len = t->len >> 1; |
| ss->read_bufs = sprd_spi_read_bufs_u16; |
| ss->write_bufs = sprd_spi_write_bufs_u16; |
| ss->dma.width = DMA_SLAVE_BUSWIDTH_2_BYTES; |
| ss->dma.fragmens_len = SPRD_SPI_DMA_STEP << 1; |
| break; |
| case 32: |
| ss->trans_len = t->len >> 2; |
| ss->read_bufs = sprd_spi_read_bufs_u32; |
| ss->write_bufs = sprd_spi_write_bufs_u32; |
| ss->dma.width = DMA_SLAVE_BUSWIDTH_4_BYTES; |
| ss->dma.fragmens_len = SPRD_SPI_DMA_STEP << 2; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| /* Set transfer read or write mode */ |
| val = readl_relaxed(ss->base + SPRD_SPI_CTL1); |
| val &= ~SPRD_SPI_RTX_MD_MASK; |
| if (t->tx_buf) |
| mode |= SPRD_SPI_TX_MODE; |
| if (t->rx_buf) |
| mode |= SPRD_SPI_RX_MODE; |
| |
| writel_relaxed(val | mode, ss->base + SPRD_SPI_CTL1); |
| |
| ss->trans_mode = mode; |
| |
| /* |
| * If in only receive mode, we need to trigger the SPI controller to |
| * receive data automatically. |
| */ |
| if (ss->trans_mode == SPRD_SPI_RX_MODE) |
| ss->write_bufs = sprd_spi_write_only_receive; |
| |
| return 0; |
| } |
| |
| static int sprd_spi_transfer_one(struct spi_controller *sctlr, |
| struct spi_device *sdev, |
| struct spi_transfer *t) |
| { |
| int ret; |
| |
| ret = sprd_spi_setup_transfer(sdev, t); |
| if (ret) |
| goto setup_err; |
| |
| if (sctlr->can_dma(sctlr, sdev, t)) |
| ret = sprd_spi_dma_txrx_bufs(sdev, t); |
| else |
| ret = sprd_spi_txrx_bufs(sdev, t); |
| |
| if (ret == t->len) |
| ret = 0; |
| else if (ret >= 0) |
| ret = -EREMOTEIO; |
| |
| setup_err: |
| spi_finalize_current_transfer(sctlr); |
| |
| return ret; |
| } |
| |
| static irqreturn_t sprd_spi_handle_irq(int irq, void *data) |
| { |
| struct sprd_spi *ss = (struct sprd_spi *)data; |
| u32 val = readl_relaxed(ss->base + SPRD_SPI_INT_MASK_STS); |
| |
| if (val & SPRD_SPI_MASK_TX_END) { |
| writel_relaxed(SPRD_SPI_TX_END_CLR, ss->base + SPRD_SPI_INT_CLR); |
| if (!(ss->trans_mode & SPRD_SPI_RX_MODE)) |
| complete(&ss->xfer_completion); |
| |
| return IRQ_HANDLED; |
| } |
| |
| if (val & SPRD_SPI_MASK_RX_END) { |
| writel_relaxed(SPRD_SPI_RX_END_CLR, ss->base + SPRD_SPI_INT_CLR); |
| if (ss->dma.rx_len < ss->len) { |
| ss->rx_buf += ss->dma.rx_len; |
| ss->dma.rx_len += |
| ss->read_bufs(ss, ss->len - ss->dma.rx_len); |
| } |
| complete(&ss->xfer_completion); |
| |
| return IRQ_HANDLED; |
| } |
| |
| return IRQ_NONE; |
| } |
| |
| static int sprd_spi_irq_init(struct platform_device *pdev, struct sprd_spi *ss) |
| { |
| int ret; |
| |
| ss->irq = platform_get_irq(pdev, 0); |
| if (ss->irq < 0) |
| return ss->irq; |
| |
| ret = devm_request_irq(&pdev->dev, ss->irq, sprd_spi_handle_irq, |
| 0, pdev->name, ss); |
| if (ret) |
| dev_err(&pdev->dev, "failed to request spi irq %d, ret = %d\n", |
| ss->irq, ret); |
| |
| return ret; |
| } |
| |
| static int sprd_spi_clk_init(struct platform_device *pdev, struct sprd_spi *ss) |
| { |
| struct clk *clk_spi, *clk_parent; |
| |
| clk_spi = devm_clk_get(&pdev->dev, "spi"); |
| if (IS_ERR(clk_spi)) { |
| dev_warn(&pdev->dev, "can't get the spi clock\n"); |
| clk_spi = NULL; |
| } |
| |
| clk_parent = devm_clk_get(&pdev->dev, "source"); |
| if (IS_ERR(clk_parent)) { |
| dev_warn(&pdev->dev, "can't get the source clock\n"); |
| clk_parent = NULL; |
| } |
| |
| ss->clk = devm_clk_get(&pdev->dev, "enable"); |
| if (IS_ERR(ss->clk)) { |
| dev_err(&pdev->dev, "can't get the enable clock\n"); |
| return PTR_ERR(ss->clk); |
| } |
| |
| if (!clk_set_parent(clk_spi, clk_parent)) |
| ss->src_clk = clk_get_rate(clk_spi); |
| else |
| ss->src_clk = SPRD_SPI_DEFAULT_SOURCE; |
| |
| return 0; |
| } |
| |
| static bool sprd_spi_can_dma(struct spi_controller *sctlr, |
| struct spi_device *spi, struct spi_transfer *t) |
| { |
| struct sprd_spi *ss = spi_controller_get_devdata(sctlr); |
| |
| return ss->dma.enable && (t->len > SPRD_SPI_FIFO_SIZE); |
| } |
| |
| static int sprd_spi_dma_init(struct platform_device *pdev, struct sprd_spi *ss) |
| { |
| int ret; |
| |
| ret = sprd_spi_dma_request(ss); |
| if (ret) { |
| if (ret == -EPROBE_DEFER) |
| return ret; |
| |
| dev_warn(&pdev->dev, |
| "failed to request dma, enter no dma mode, ret = %d\n", |
| ret); |
| |
| return 0; |
| } |
| |
| ss->dma.enable = true; |
| |
| return 0; |
| } |
| |
| static int sprd_spi_probe(struct platform_device *pdev) |
| { |
| struct spi_controller *sctlr; |
| struct resource *res; |
| struct sprd_spi *ss; |
| int ret; |
| |
| pdev->id = of_alias_get_id(pdev->dev.of_node, "spi"); |
| sctlr = spi_alloc_master(&pdev->dev, sizeof(*ss)); |
| if (!sctlr) |
| return -ENOMEM; |
| |
| ss = spi_controller_get_devdata(sctlr); |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| ss->base = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(ss->base)) { |
| ret = PTR_ERR(ss->base); |
| goto free_controller; |
| } |
| |
| ss->phy_base = res->start; |
| ss->dev = &pdev->dev; |
| sctlr->dev.of_node = pdev->dev.of_node; |
| sctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE | SPI_TX_DUAL; |
| sctlr->bus_num = pdev->id; |
| sctlr->set_cs = sprd_spi_chipselect; |
| sctlr->transfer_one = sprd_spi_transfer_one; |
| sctlr->can_dma = sprd_spi_can_dma; |
| sctlr->auto_runtime_pm = true; |
| sctlr->max_speed_hz = min_t(u32, ss->src_clk >> 1, |
| SPRD_SPI_MAX_SPEED_HZ); |
| |
| init_completion(&ss->xfer_completion); |
| platform_set_drvdata(pdev, sctlr); |
| ret = sprd_spi_clk_init(pdev, ss); |
| if (ret) |
| goto free_controller; |
| |
| ret = sprd_spi_irq_init(pdev, ss); |
| if (ret) |
| goto free_controller; |
| |
| ret = sprd_spi_dma_init(pdev, ss); |
| if (ret) |
| goto free_controller; |
| |
| ret = clk_prepare_enable(ss->clk); |
| if (ret) |
| goto release_dma; |
| |
| ret = pm_runtime_set_active(&pdev->dev); |
| if (ret < 0) |
| goto disable_clk; |
| |
| pm_runtime_set_autosuspend_delay(&pdev->dev, |
| SPRD_SPI_AUTOSUSPEND_DELAY); |
| pm_runtime_use_autosuspend(&pdev->dev); |
| pm_runtime_enable(&pdev->dev); |
| ret = pm_runtime_get_sync(&pdev->dev); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "failed to resume SPI controller\n"); |
| goto err_rpm_put; |
| } |
| |
| ret = devm_spi_register_controller(&pdev->dev, sctlr); |
| if (ret) |
| goto err_rpm_put; |
| |
| pm_runtime_mark_last_busy(&pdev->dev); |
| pm_runtime_put_autosuspend(&pdev->dev); |
| |
| return 0; |
| |
| err_rpm_put: |
| pm_runtime_put_noidle(&pdev->dev); |
| pm_runtime_disable(&pdev->dev); |
| disable_clk: |
| clk_disable_unprepare(ss->clk); |
| release_dma: |
| sprd_spi_dma_release(ss); |
| free_controller: |
| spi_controller_put(sctlr); |
| |
| return ret; |
| } |
| |
| static int sprd_spi_remove(struct platform_device *pdev) |
| { |
| struct spi_controller *sctlr = platform_get_drvdata(pdev); |
| struct sprd_spi *ss = spi_controller_get_devdata(sctlr); |
| int ret; |
| |
| ret = pm_runtime_get_sync(ss->dev); |
| if (ret < 0) { |
| dev_err(ss->dev, "failed to resume SPI controller\n"); |
| return ret; |
| } |
| |
| spi_controller_suspend(sctlr); |
| |
| if (ss->dma.enable) |
| sprd_spi_dma_release(ss); |
| clk_disable_unprepare(ss->clk); |
| pm_runtime_put_noidle(&pdev->dev); |
| pm_runtime_disable(&pdev->dev); |
| |
| return 0; |
| } |
| |
| static int __maybe_unused sprd_spi_runtime_suspend(struct device *dev) |
| { |
| struct spi_controller *sctlr = dev_get_drvdata(dev); |
| struct sprd_spi *ss = spi_controller_get_devdata(sctlr); |
| |
| if (ss->dma.enable) |
| sprd_spi_dma_release(ss); |
| |
| clk_disable_unprepare(ss->clk); |
| |
| return 0; |
| } |
| |
| static int __maybe_unused sprd_spi_runtime_resume(struct device *dev) |
| { |
| struct spi_controller *sctlr = dev_get_drvdata(dev); |
| struct sprd_spi *ss = spi_controller_get_devdata(sctlr); |
| int ret; |
| |
| ret = clk_prepare_enable(ss->clk); |
| if (ret) |
| return ret; |
| |
| if (!ss->dma.enable) |
| return 0; |
| |
| ret = sprd_spi_dma_request(ss); |
| if (ret) |
| clk_disable_unprepare(ss->clk); |
| |
| return ret; |
| } |
| |
| static const struct dev_pm_ops sprd_spi_pm_ops = { |
| SET_RUNTIME_PM_OPS(sprd_spi_runtime_suspend, |
| sprd_spi_runtime_resume, NULL) |
| }; |
| |
| static const struct of_device_id sprd_spi_of_match[] = { |
| { .compatible = "sprd,sc9860-spi", }, |
| { /* sentinel */ } |
| }; |
| |
| static struct platform_driver sprd_spi_driver = { |
| .driver = { |
| .name = "sprd-spi", |
| .of_match_table = sprd_spi_of_match, |
| .pm = &sprd_spi_pm_ops, |
| }, |
| .probe = sprd_spi_probe, |
| .remove = sprd_spi_remove, |
| }; |
| |
| module_platform_driver(sprd_spi_driver); |
| |
| MODULE_DESCRIPTION("Spreadtrum SPI Controller driver"); |
| MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>"); |
| MODULE_LICENSE("GPL v2"); |