diff options
Diffstat (limited to 'drivers/spi/spi-sun6i.c')
-rw-r--r-- | drivers/spi/spi-sun6i.c | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c new file mode 100644 index 000000000..d79853ba7 --- /dev/null +++ b/drivers/spi/spi-sun6i.c @@ -0,0 +1,752 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2012 - 2014 Allwinner Tech + * Pan Nan <pannan@allwinnertech.com> + * + * Copyright (C) 2014 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/dmaengine.h> + +#include <linux/spi/spi.h> + +#define SUN6I_AUTOSUSPEND_TIMEOUT 2000 + +#define SUN6I_FIFO_DEPTH 128 +#define SUN8I_FIFO_DEPTH 64 + +#define SUN6I_GBL_CTL_REG 0x04 +#define SUN6I_GBL_CTL_BUS_ENABLE BIT(0) +#define SUN6I_GBL_CTL_MASTER BIT(1) +#define SUN6I_GBL_CTL_TP BIT(7) +#define SUN6I_GBL_CTL_RST BIT(31) + +#define SUN6I_TFR_CTL_REG 0x08 +#define SUN6I_TFR_CTL_CPHA BIT(0) +#define SUN6I_TFR_CTL_CPOL BIT(1) +#define SUN6I_TFR_CTL_SPOL BIT(2) +#define SUN6I_TFR_CTL_CS_MASK 0x30 +#define SUN6I_TFR_CTL_CS(cs) (((cs) << 4) & SUN6I_TFR_CTL_CS_MASK) +#define SUN6I_TFR_CTL_CS_MANUAL BIT(6) +#define SUN6I_TFR_CTL_CS_LEVEL BIT(7) +#define SUN6I_TFR_CTL_DHB BIT(8) +#define SUN6I_TFR_CTL_FBS BIT(12) +#define SUN6I_TFR_CTL_XCH BIT(31) + +#define SUN6I_INT_CTL_REG 0x10 +#define SUN6I_INT_CTL_RF_RDY BIT(0) +#define SUN6I_INT_CTL_TF_ERQ BIT(4) +#define SUN6I_INT_CTL_RF_OVF BIT(8) +#define SUN6I_INT_CTL_TC BIT(12) + +#define SUN6I_INT_STA_REG 0x14 + +#define SUN6I_FIFO_CTL_REG 0x18 +#define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_MASK 0xff +#define SUN6I_FIFO_CTL_RF_DRQ_EN BIT(8) +#define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS 0 +#define SUN6I_FIFO_CTL_RF_RST BIT(15) +#define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_MASK 0xff +#define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS 16 +#define SUN6I_FIFO_CTL_TF_DRQ_EN BIT(24) +#define SUN6I_FIFO_CTL_TF_RST BIT(31) + +#define SUN6I_FIFO_STA_REG 0x1c +#define SUN6I_FIFO_STA_RF_CNT_MASK GENMASK(7, 0) +#define SUN6I_FIFO_STA_TF_CNT_MASK GENMASK(23, 16) + +#define SUN6I_CLK_CTL_REG 0x24 +#define SUN6I_CLK_CTL_CDR2_MASK 0xff +#define SUN6I_CLK_CTL_CDR2(div) (((div) & SUN6I_CLK_CTL_CDR2_MASK) << 0) +#define SUN6I_CLK_CTL_CDR1_MASK 0xf +#define SUN6I_CLK_CTL_CDR1(div) (((div) & SUN6I_CLK_CTL_CDR1_MASK) << 8) +#define SUN6I_CLK_CTL_DRS BIT(12) + +#define SUN6I_MAX_XFER_SIZE 0xffffff + +#define SUN6I_BURST_CNT_REG 0x30 + +#define SUN6I_XMIT_CNT_REG 0x34 + +#define SUN6I_BURST_CTL_CNT_REG 0x38 + +#define SUN6I_TXDATA_REG 0x200 +#define SUN6I_RXDATA_REG 0x300 + +struct sun6i_spi { + struct spi_master *master; + void __iomem *base_addr; + dma_addr_t dma_addr_rx; + dma_addr_t dma_addr_tx; + struct clk *hclk; + struct clk *mclk; + struct reset_control *rstc; + + struct completion done; + struct completion dma_rx_done; + + const u8 *tx_buf; + u8 *rx_buf; + int len; + unsigned long fifo_depth; +}; + +static inline u32 sun6i_spi_read(struct sun6i_spi *sspi, u32 reg) +{ + return readl(sspi->base_addr + reg); +} + +static inline void sun6i_spi_write(struct sun6i_spi *sspi, u32 reg, u32 value) +{ + writel(value, sspi->base_addr + reg); +} + +static inline u32 sun6i_spi_get_rx_fifo_count(struct sun6i_spi *sspi) +{ + u32 reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG); + + return FIELD_GET(SUN6I_FIFO_STA_RF_CNT_MASK, reg); +} + +static inline u32 sun6i_spi_get_tx_fifo_count(struct sun6i_spi *sspi) +{ + u32 reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG); + + return FIELD_GET(SUN6I_FIFO_STA_TF_CNT_MASK, reg); +} + +static inline void sun6i_spi_disable_interrupt(struct sun6i_spi *sspi, u32 mask) +{ + u32 reg = sun6i_spi_read(sspi, SUN6I_INT_CTL_REG); + + reg &= ~mask; + sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg); +} + +static inline void sun6i_spi_drain_fifo(struct sun6i_spi *sspi) +{ + u32 len; + u8 byte; + + /* See how much data is available */ + len = sun6i_spi_get_rx_fifo_count(sspi); + + while (len--) { + byte = readb(sspi->base_addr + SUN6I_RXDATA_REG); + if (sspi->rx_buf) + *sspi->rx_buf++ = byte; + } +} + +static inline void sun6i_spi_fill_fifo(struct sun6i_spi *sspi) +{ + u32 cnt; + int len; + u8 byte; + + /* See how much data we can fit */ + cnt = sspi->fifo_depth - sun6i_spi_get_tx_fifo_count(sspi); + + len = min((int)cnt, sspi->len); + + while (len--) { + byte = sspi->tx_buf ? *sspi->tx_buf++ : 0; + writeb(byte, sspi->base_addr + SUN6I_TXDATA_REG); + sspi->len--; + } +} + +static void sun6i_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct sun6i_spi *sspi = spi_master_get_devdata(spi->master); + u32 reg; + + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + reg &= ~SUN6I_TFR_CTL_CS_MASK; + reg |= SUN6I_TFR_CTL_CS(spi->chip_select); + + if (enable) + reg |= SUN6I_TFR_CTL_CS_LEVEL; + else + reg &= ~SUN6I_TFR_CTL_CS_LEVEL; + + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg); +} + +static size_t sun6i_spi_max_transfer_size(struct spi_device *spi) +{ + return SUN6I_MAX_XFER_SIZE - 1; +} + +static void sun6i_spi_dma_rx_cb(void *param) +{ + struct sun6i_spi *sspi = param; + + complete(&sspi->dma_rx_done); +} + +static int sun6i_spi_prepare_dma(struct sun6i_spi *sspi, + struct spi_transfer *tfr) +{ + struct dma_async_tx_descriptor *rxdesc, *txdesc; + struct spi_master *master = sspi->master; + + rxdesc = NULL; + if (tfr->rx_buf) { + struct dma_slave_config rxconf = { + .direction = DMA_DEV_TO_MEM, + .src_addr = sspi->dma_addr_rx, + .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, + .src_maxburst = 8, + }; + + dmaengine_slave_config(master->dma_rx, &rxconf); + + rxdesc = dmaengine_prep_slave_sg(master->dma_rx, + tfr->rx_sg.sgl, + tfr->rx_sg.nents, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT); + if (!rxdesc) + return -EINVAL; + rxdesc->callback_param = sspi; + rxdesc->callback = sun6i_spi_dma_rx_cb; + } + + txdesc = NULL; + if (tfr->tx_buf) { + struct dma_slave_config txconf = { + .direction = DMA_MEM_TO_DEV, + .dst_addr = sspi->dma_addr_tx, + .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, + .dst_maxburst = 8, + }; + + dmaengine_slave_config(master->dma_tx, &txconf); + + txdesc = dmaengine_prep_slave_sg(master->dma_tx, + tfr->tx_sg.sgl, + tfr->tx_sg.nents, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT); + if (!txdesc) { + if (rxdesc) + dmaengine_terminate_sync(master->dma_rx); + return -EINVAL; + } + } + + if (tfr->rx_buf) { + dmaengine_submit(rxdesc); + dma_async_issue_pending(master->dma_rx); + } + + if (tfr->tx_buf) { + dmaengine_submit(txdesc); + dma_async_issue_pending(master->dma_tx); + } + + return 0; +} + +static int sun6i_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *tfr) +{ + struct sun6i_spi *sspi = spi_master_get_devdata(master); + unsigned int mclk_rate, div, div_cdr1, div_cdr2, timeout; + unsigned int start, end, tx_time; + unsigned int trig_level; + unsigned int tx_len = 0, rx_len = 0; + bool use_dma; + int ret = 0; + u32 reg; + + if (tfr->len > SUN6I_MAX_XFER_SIZE) + return -EINVAL; + + reinit_completion(&sspi->done); + reinit_completion(&sspi->dma_rx_done); + sspi->tx_buf = tfr->tx_buf; + sspi->rx_buf = tfr->rx_buf; + sspi->len = tfr->len; + use_dma = master->can_dma ? master->can_dma(master, spi, tfr) : false; + + /* Clear pending interrupts */ + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, ~0); + + /* Reset FIFO */ + sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG, + SUN6I_FIFO_CTL_RF_RST | SUN6I_FIFO_CTL_TF_RST); + + reg = 0; + + if (!use_dma) { + /* + * Setup FIFO interrupt trigger level + * Here we choose 3/4 of the full fifo depth, as it's + * the hardcoded value used in old generation of Allwinner + * SPI controller. (See spi-sun4i.c) + */ + trig_level = sspi->fifo_depth / 4 * 3; + } else { + /* + * Setup FIFO DMA request trigger level + * We choose 1/2 of the full fifo depth, that value will + * be used as DMA burst length. + */ + trig_level = sspi->fifo_depth / 2; + + if (tfr->tx_buf) + reg |= SUN6I_FIFO_CTL_TF_DRQ_EN; + if (tfr->rx_buf) + reg |= SUN6I_FIFO_CTL_RF_DRQ_EN; + } + + reg |= (trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS) | + (trig_level << SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS); + + sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG, reg); + + /* + * Setup the transfer control register: Chip Select, + * polarities, etc. + */ + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + + if (spi->mode & SPI_CPOL) + reg |= SUN6I_TFR_CTL_CPOL; + else + reg &= ~SUN6I_TFR_CTL_CPOL; + + if (spi->mode & SPI_CPHA) + reg |= SUN6I_TFR_CTL_CPHA; + else + reg &= ~SUN6I_TFR_CTL_CPHA; + + if (spi->mode & SPI_LSB_FIRST) + reg |= SUN6I_TFR_CTL_FBS; + else + reg &= ~SUN6I_TFR_CTL_FBS; + + /* + * If it's a TX only transfer, we don't want to fill the RX + * FIFO with bogus data + */ + if (sspi->rx_buf) { + reg &= ~SUN6I_TFR_CTL_DHB; + rx_len = tfr->len; + } else { + reg |= SUN6I_TFR_CTL_DHB; + } + + /* We want to control the chip select manually */ + reg |= SUN6I_TFR_CTL_CS_MANUAL; + + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg); + + /* Ensure that we have a parent clock fast enough */ + mclk_rate = clk_get_rate(sspi->mclk); + if (mclk_rate < (2 * tfr->speed_hz)) { + clk_set_rate(sspi->mclk, 2 * tfr->speed_hz); + mclk_rate = clk_get_rate(sspi->mclk); + } + + /* + * Setup clock divider. + * + * We have two choices there. Either we can use the clock + * divide rate 1, which is calculated thanks to this formula: + * SPI_CLK = MOD_CLK / (2 ^ cdr) + * Or we can use CDR2, which is calculated with the formula: + * SPI_CLK = MOD_CLK / (2 * (cdr + 1)) + * Wether we use the former or the latter is set through the + * DRS bit. + * + * First try CDR2, and if we can't reach the expected + * frequency, fall back to CDR1. + */ + div_cdr1 = DIV_ROUND_UP(mclk_rate, tfr->speed_hz); + div_cdr2 = DIV_ROUND_UP(div_cdr1, 2); + if (div_cdr2 <= (SUN6I_CLK_CTL_CDR2_MASK + 1)) { + reg = SUN6I_CLK_CTL_CDR2(div_cdr2 - 1) | SUN6I_CLK_CTL_DRS; + tfr->effective_speed_hz = mclk_rate / (2 * div_cdr2); + } else { + div = min(SUN6I_CLK_CTL_CDR1_MASK, order_base_2(div_cdr1)); + reg = SUN6I_CLK_CTL_CDR1(div); + tfr->effective_speed_hz = mclk_rate / (1 << div); + } + + sun6i_spi_write(sspi, SUN6I_CLK_CTL_REG, reg); + /* Finally enable the bus - doing so before might raise SCK to HIGH */ + reg = sun6i_spi_read(sspi, SUN6I_GBL_CTL_REG); + reg |= SUN6I_GBL_CTL_BUS_ENABLE; + sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG, reg); + + /* Setup the transfer now... */ + if (sspi->tx_buf) + tx_len = tfr->len; + + /* Setup the counters */ + sun6i_spi_write(sspi, SUN6I_BURST_CNT_REG, tfr->len); + sun6i_spi_write(sspi, SUN6I_XMIT_CNT_REG, tx_len); + sun6i_spi_write(sspi, SUN6I_BURST_CTL_CNT_REG, tx_len); + + if (!use_dma) { + /* Fill the TX FIFO */ + sun6i_spi_fill_fifo(sspi); + } else { + ret = sun6i_spi_prepare_dma(sspi, tfr); + if (ret) { + dev_warn(&master->dev, + "%s: prepare DMA failed, ret=%d", + dev_name(&spi->dev), ret); + return ret; + } + } + + /* Enable the interrupts */ + reg = SUN6I_INT_CTL_TC; + + if (!use_dma) { + if (rx_len > sspi->fifo_depth) + reg |= SUN6I_INT_CTL_RF_RDY; + if (tx_len > sspi->fifo_depth) + reg |= SUN6I_INT_CTL_TF_ERQ; + } + + sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg); + + /* Start the transfer */ + reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG); + sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg | SUN6I_TFR_CTL_XCH); + + tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U); + start = jiffies; + timeout = wait_for_completion_timeout(&sspi->done, + msecs_to_jiffies(tx_time)); + + if (!use_dma) { + sun6i_spi_drain_fifo(sspi); + } else { + if (timeout && rx_len) { + /* + * Even though RX on the peripheral side has finished + * RX DMA might still be in flight + */ + timeout = wait_for_completion_timeout(&sspi->dma_rx_done, + timeout); + if (!timeout) + dev_warn(&master->dev, "RX DMA timeout\n"); + } + } + + end = jiffies; + if (!timeout) { + dev_warn(&master->dev, + "%s: timeout transferring %u bytes@%iHz for %i(%i)ms", + dev_name(&spi->dev), tfr->len, tfr->speed_hz, + jiffies_to_msecs(end - start), tx_time); + ret = -ETIMEDOUT; + } + + sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0); + + if (ret && use_dma) { + dmaengine_terminate_sync(master->dma_rx); + dmaengine_terminate_sync(master->dma_tx); + } + + return ret; +} + +static irqreturn_t sun6i_spi_handler(int irq, void *dev_id) +{ + struct sun6i_spi *sspi = dev_id; + u32 status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG); + + /* Transfer complete */ + if (status & SUN6I_INT_CTL_TC) { + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TC); + complete(&sspi->done); + return IRQ_HANDLED; + } + + /* Receive FIFO 3/4 full */ + if (status & SUN6I_INT_CTL_RF_RDY) { + sun6i_spi_drain_fifo(sspi); + /* Only clear the interrupt _after_ draining the FIFO */ + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_RF_RDY); + return IRQ_HANDLED; + } + + /* Transmit FIFO 3/4 empty */ + if (status & SUN6I_INT_CTL_TF_ERQ) { + sun6i_spi_fill_fifo(sspi); + + if (!sspi->len) + /* nothing left to transmit */ + sun6i_spi_disable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ); + + /* Only clear the interrupt _after_ re-seeding the FIFO */ + sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TF_ERQ); + + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int sun6i_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun6i_spi *sspi = spi_master_get_devdata(master); + int ret; + + ret = clk_prepare_enable(sspi->hclk); + if (ret) { + dev_err(dev, "Couldn't enable AHB clock\n"); + goto out; + } + + ret = clk_prepare_enable(sspi->mclk); + if (ret) { + dev_err(dev, "Couldn't enable module clock\n"); + goto err; + } + + ret = reset_control_deassert(sspi->rstc); + if (ret) { + dev_err(dev, "Couldn't deassert the device from reset\n"); + goto err2; + } + + sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG, + SUN6I_GBL_CTL_MASTER | SUN6I_GBL_CTL_TP); + + return 0; + +err2: + clk_disable_unprepare(sspi->mclk); +err: + clk_disable_unprepare(sspi->hclk); +out: + return ret; +} + +static int sun6i_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct sun6i_spi *sspi = spi_master_get_devdata(master); + + reset_control_assert(sspi->rstc); + clk_disable_unprepare(sspi->mclk); + clk_disable_unprepare(sspi->hclk); + + return 0; +} + +static bool sun6i_spi_can_dma(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct sun6i_spi *sspi = spi_master_get_devdata(master); + + /* + * If the number of spi words to transfer is less or equal than + * the fifo length we can just fill the fifo and wait for a single + * irq, so don't bother setting up dma + */ + return xfer->len > sspi->fifo_depth; +} + +static int sun6i_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct sun6i_spi *sspi; + struct resource *mem; + int ret = 0, irq; + + master = spi_alloc_master(&pdev->dev, sizeof(struct sun6i_spi)); + if (!master) { + dev_err(&pdev->dev, "Unable to allocate SPI Master\n"); + return -ENOMEM; + } + + platform_set_drvdata(pdev, master); + sspi = spi_master_get_devdata(master); + + sspi->base_addr = devm_platform_get_and_ioremap_resource(pdev, 0, &mem); + if (IS_ERR(sspi->base_addr)) { + ret = PTR_ERR(sspi->base_addr); + goto err_free_master; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = -ENXIO; + goto err_free_master; + } + + ret = devm_request_irq(&pdev->dev, irq, sun6i_spi_handler, + 0, "sun6i-spi", sspi); + if (ret) { + dev_err(&pdev->dev, "Cannot request IRQ\n"); + goto err_free_master; + } + + sspi->master = master; + sspi->fifo_depth = (unsigned long)of_device_get_match_data(&pdev->dev); + + master->max_speed_hz = 100 * 1000 * 1000; + master->min_speed_hz = 3 * 1000; + master->use_gpio_descriptors = true; + master->set_cs = sun6i_spi_set_cs; + master->transfer_one = sun6i_spi_transfer_one; + master->num_chipselect = 4; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->dev.of_node = pdev->dev.of_node; + master->auto_runtime_pm = true; + master->max_transfer_size = sun6i_spi_max_transfer_size; + + sspi->hclk = devm_clk_get(&pdev->dev, "ahb"); + if (IS_ERR(sspi->hclk)) { + dev_err(&pdev->dev, "Unable to acquire AHB clock\n"); + ret = PTR_ERR(sspi->hclk); + goto err_free_master; + } + + sspi->mclk = devm_clk_get(&pdev->dev, "mod"); + if (IS_ERR(sspi->mclk)) { + dev_err(&pdev->dev, "Unable to acquire module clock\n"); + ret = PTR_ERR(sspi->mclk); + goto err_free_master; + } + + init_completion(&sspi->done); + init_completion(&sspi->dma_rx_done); + + sspi->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (IS_ERR(sspi->rstc)) { + dev_err(&pdev->dev, "Couldn't get reset controller\n"); + ret = PTR_ERR(sspi->rstc); + goto err_free_master; + } + + master->dma_tx = dma_request_chan(&pdev->dev, "tx"); + if (IS_ERR(master->dma_tx)) { + /* Check tx to see if we need defer probing driver */ + if (PTR_ERR(master->dma_tx) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto err_free_master; + } + dev_warn(&pdev->dev, "Failed to request TX DMA channel\n"); + master->dma_tx = NULL; + } + + master->dma_rx = dma_request_chan(&pdev->dev, "rx"); + if (IS_ERR(master->dma_rx)) { + if (PTR_ERR(master->dma_rx) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto err_free_dma_tx; + } + dev_warn(&pdev->dev, "Failed to request RX DMA channel\n"); + master->dma_rx = NULL; + } + + if (master->dma_tx && master->dma_rx) { + sspi->dma_addr_tx = mem->start + SUN6I_TXDATA_REG; + sspi->dma_addr_rx = mem->start + SUN6I_RXDATA_REG; + master->can_dma = sun6i_spi_can_dma; + } + + /* + * This wake-up/shutdown pattern is to be able to have the + * device woken up, even if runtime_pm is disabled + */ + ret = sun6i_spi_runtime_resume(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, "Couldn't resume the device\n"); + goto err_free_dma_rx; + } + + pm_runtime_set_autosuspend_delay(&pdev->dev, SUN6I_AUTOSUSPEND_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "cannot register SPI master\n"); + goto err_pm_disable; + } + + return 0; + +err_pm_disable: + pm_runtime_disable(&pdev->dev); + sun6i_spi_runtime_suspend(&pdev->dev); +err_free_dma_rx: + if (master->dma_rx) + dma_release_channel(master->dma_rx); +err_free_dma_tx: + if (master->dma_tx) + dma_release_channel(master->dma_tx); +err_free_master: + spi_master_put(master); + return ret; +} + +static int sun6i_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + + pm_runtime_force_suspend(&pdev->dev); + + if (master->dma_tx) + dma_release_channel(master->dma_tx); + if (master->dma_rx) + dma_release_channel(master->dma_rx); + return 0; +} + +static const struct of_device_id sun6i_spi_match[] = { + { .compatible = "allwinner,sun6i-a31-spi", .data = (void *)SUN6I_FIFO_DEPTH }, + { .compatible = "allwinner,sun8i-h3-spi", .data = (void *)SUN8I_FIFO_DEPTH }, + {} +}; +MODULE_DEVICE_TABLE(of, sun6i_spi_match); + +static const struct dev_pm_ops sun6i_spi_pm_ops = { + .runtime_resume = sun6i_spi_runtime_resume, + .runtime_suspend = sun6i_spi_runtime_suspend, +}; + +static struct platform_driver sun6i_spi_driver = { + .probe = sun6i_spi_probe, + .remove = sun6i_spi_remove, + .driver = { + .name = "sun6i-spi", + .of_match_table = sun6i_spi_match, + .pm = &sun6i_spi_pm_ops, + }, +}; +module_platform_driver(sun6i_spi_driver); + +MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner A31 SPI controller driver"); +MODULE_LICENSE("GPL"); |