| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Maxime Ripard | 1804 | 81.78% | 1 | 9.09% |
| Alexandru Gagniuc | 243 | 11.02% | 1 | 9.09% |
| Michal Suchanek | 134 | 6.07% | 4 | 36.36% |
| Marcus Weseloh | 13 | 0.59% | 2 | 18.18% |
| Axel Lin | 9 | 0.41% | 1 | 9.09% |
| Thomas Gleixner | 2 | 0.09% | 1 | 9.09% |
| Takuo Koguchi | 1 | 0.05% | 1 | 9.09% |
| Total | 2206 | 11 |
// 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/clk.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/spi/spi.h> #define SUN4I_FIFO_DEPTH 64 #define SUN4I_RXDATA_REG 0x00 #define SUN4I_TXDATA_REG 0x04 #define SUN4I_CTL_REG 0x08 #define SUN4I_CTL_ENABLE BIT(0) #define SUN4I_CTL_MASTER BIT(1) #define SUN4I_CTL_CPHA BIT(2) #define SUN4I_CTL_CPOL BIT(3) #define SUN4I_CTL_CS_ACTIVE_LOW BIT(4) #define SUN4I_CTL_LMTF BIT(6) #define SUN4I_CTL_TF_RST BIT(8) #define SUN4I_CTL_RF_RST BIT(9) #define SUN4I_CTL_XCH BIT(10) #define SUN4I_CTL_CS_MASK 0x3000 #define SUN4I_CTL_CS(cs) (((cs) << 12) & SUN4I_CTL_CS_MASK) #define SUN4I_CTL_DHB BIT(15) #define SUN4I_CTL_CS_MANUAL BIT(16) #define SUN4I_CTL_CS_LEVEL BIT(17) #define SUN4I_CTL_TP BIT(18) #define SUN4I_INT_CTL_REG 0x0c #define SUN4I_INT_CTL_RF_F34 BIT(4) #define SUN4I_INT_CTL_TF_E34 BIT(12) #define SUN4I_INT_CTL_TC BIT(16) #define SUN4I_INT_STA_REG 0x10 #define SUN4I_DMA_CTL_REG 0x14 #define SUN4I_WAIT_REG 0x18 #define SUN4I_CLK_CTL_REG 0x1c #define SUN4I_CLK_CTL_CDR2_MASK 0xff #define SUN4I_CLK_CTL_CDR2(div) ((div) & SUN4I_CLK_CTL_CDR2_MASK) #define SUN4I_CLK_CTL_CDR1_MASK 0xf #define SUN4I_CLK_CTL_CDR1(div) (((div) & SUN4I_CLK_CTL_CDR1_MASK) << 8) #define SUN4I_CLK_CTL_DRS BIT(12) #define SUN4I_MAX_XFER_SIZE 0xffffff #define SUN4I_BURST_CNT_REG 0x20 #define SUN4I_BURST_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE) #define SUN4I_XMIT_CNT_REG 0x24 #define SUN4I_XMIT_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE) #define SUN4I_FIFO_STA_REG 0x28 #define SUN4I_FIFO_STA_RF_CNT_MASK 0x7f #define SUN4I_FIFO_STA_RF_CNT_BITS 0 #define SUN4I_FIFO_STA_TF_CNT_MASK 0x7f #define SUN4I_FIFO_STA_TF_CNT_BITS 16 struct sun4i_spi { struct spi_master *master; void __iomem *base_addr; struct clk *hclk; struct clk *mclk; struct completion done; const u8 *tx_buf; u8 *rx_buf; int len; }; static inline u32 sun4i_spi_read(struct sun4i_spi *sspi, u32 reg) { return readl(sspi->base_addr + reg); } static inline void sun4i_spi_write(struct sun4i_spi *sspi, u32 reg, u32 value) { writel(value, sspi->base_addr + reg); } static inline u32 sun4i_spi_get_tx_fifo_count(struct sun4i_spi *sspi) { u32 reg = sun4i_spi_read(sspi, SUN4I_FIFO_STA_REG); reg >>= SUN4I_FIFO_STA_TF_CNT_BITS; return reg & SUN4I_FIFO_STA_TF_CNT_MASK; } static inline void sun4i_spi_enable_interrupt(struct sun4i_spi *sspi, u32 mask) { u32 reg = sun4i_spi_read(sspi, SUN4I_INT_CTL_REG); reg |= mask; sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, reg); } static inline void sun4i_spi_disable_interrupt(struct sun4i_spi *sspi, u32 mask) { u32 reg = sun4i_spi_read(sspi, SUN4I_INT_CTL_REG); reg &= ~mask; sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, reg); } static inline void sun4i_spi_drain_fifo(struct sun4i_spi *sspi, int len) { u32 reg, cnt; u8 byte; /* See how much data is available */ reg = sun4i_spi_read(sspi, SUN4I_FIFO_STA_REG); reg &= SUN4I_FIFO_STA_RF_CNT_MASK; cnt = reg >> SUN4I_FIFO_STA_RF_CNT_BITS; if (len > cnt) len = cnt; while (len--) { byte = readb(sspi->base_addr + SUN4I_RXDATA_REG); if (sspi->rx_buf) *sspi->rx_buf++ = byte; } } static inline void sun4i_spi_fill_fifo(struct sun4i_spi *sspi, int len) { u32 cnt; u8 byte; /* See how much data we can fit */ cnt = SUN4I_FIFO_DEPTH - sun4i_spi_get_tx_fifo_count(sspi); len = min3(len, (int)cnt, sspi->len); while (len--) { byte = sspi->tx_buf ? *sspi->tx_buf++ : 0; writeb(byte, sspi->base_addr + SUN4I_TXDATA_REG); sspi->len--; } } static void sun4i_spi_set_cs(struct spi_device *spi, bool enable) { struct sun4i_spi *sspi = spi_master_get_devdata(spi->master); u32 reg; reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); reg &= ~SUN4I_CTL_CS_MASK; reg |= SUN4I_CTL_CS(spi->chip_select); /* We want to control the chip select manually */ reg |= SUN4I_CTL_CS_MANUAL; if (enable) reg |= SUN4I_CTL_CS_LEVEL; else reg &= ~SUN4I_CTL_CS_LEVEL; /* * Even though this looks irrelevant since we are supposed to * be controlling the chip select manually, this bit also * controls the levels of the chip select for inactive * devices. * * If we don't set it, the chip select level will go low by * default when the device is idle, which is not really * expected in the common case where the chip select is active * low. */ if (spi->mode & SPI_CS_HIGH) reg &= ~SUN4I_CTL_CS_ACTIVE_LOW; else reg |= SUN4I_CTL_CS_ACTIVE_LOW; sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); } static size_t sun4i_spi_max_transfer_size(struct spi_device *spi) { return SUN4I_FIFO_DEPTH - 1; } static int sun4i_spi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *tfr) { struct sun4i_spi *sspi = spi_master_get_devdata(master); unsigned int mclk_rate, div, timeout; unsigned int start, end, tx_time; unsigned int tx_len = 0; int ret = 0; u32 reg; /* We don't support transfer larger than the FIFO */ if (tfr->len > SUN4I_MAX_XFER_SIZE) return -EMSGSIZE; if (tfr->tx_buf && tfr->len >= SUN4I_MAX_XFER_SIZE) return -EMSGSIZE; reinit_completion(&sspi->done); sspi->tx_buf = tfr->tx_buf; sspi->rx_buf = tfr->rx_buf; sspi->len = tfr->len; /* Clear pending interrupts */ sun4i_spi_write(sspi, SUN4I_INT_STA_REG, ~0); reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); /* Reset FIFOs */ sun4i_spi_write(sspi, SUN4I_CTL_REG, reg | SUN4I_CTL_RF_RST | SUN4I_CTL_TF_RST); /* * Setup the transfer control register: Chip Select, * polarities, etc. */ if (spi->mode & SPI_CPOL) reg |= SUN4I_CTL_CPOL; else reg &= ~SUN4I_CTL_CPOL; if (spi->mode & SPI_CPHA) reg |= SUN4I_CTL_CPHA; else reg &= ~SUN4I_CTL_CPHA; if (spi->mode & SPI_LSB_FIRST) reg |= SUN4I_CTL_LMTF; else reg &= ~SUN4I_CTL_LMTF; /* * If it's a TX only transfer, we don't want to fill the RX * FIFO with bogus data */ if (sspi->rx_buf) reg &= ~SUN4I_CTL_DHB; else reg |= SUN4I_CTL_DHB; sun4i_spi_write(sspi, SUN4I_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 + 1)) * 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 = mclk_rate / (2 * tfr->speed_hz); if (div <= (SUN4I_CLK_CTL_CDR2_MASK + 1)) { if (div > 0) div--; reg = SUN4I_CLK_CTL_CDR2(div) | SUN4I_CLK_CTL_DRS; } else { div = ilog2(mclk_rate) - ilog2(tfr->speed_hz); reg = SUN4I_CLK_CTL_CDR1(div); } sun4i_spi_write(sspi, SUN4I_CLK_CTL_REG, reg); /* Setup the transfer now... */ if (sspi->tx_buf) tx_len = tfr->len; /* Setup the counters */ sun4i_spi_write(sspi, SUN4I_BURST_CNT_REG, SUN4I_BURST_CNT(tfr->len)); sun4i_spi_write(sspi, SUN4I_XMIT_CNT_REG, SUN4I_XMIT_CNT(tx_len)); /* * Fill the TX FIFO * Filling the FIFO fully causes timeout for some reason * at least on spi2 on A10s */ sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH - 1); /* Enable the interrupts */ sun4i_spi_enable_interrupt(sspi, SUN4I_INT_CTL_TC | SUN4I_INT_CTL_RF_F34); /* Only enable Tx FIFO interrupt if we really need it */ if (tx_len > SUN4I_FIFO_DEPTH) sun4i_spi_enable_interrupt(sspi, SUN4I_INT_CTL_TF_E34); /* Start the transfer */ reg = sun4i_spi_read(sspi, SUN4I_CTL_REG); sun4i_spi_write(sspi, SUN4I_CTL_REG, reg | SUN4I_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)); 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; goto out; } out: sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, 0); return ret; } static irqreturn_t sun4i_spi_handler(int irq, void *dev_id) { struct sun4i_spi *sspi = dev_id; u32 status = sun4i_spi_read(sspi, SUN4I_INT_STA_REG); /* Transfer complete */ if (status & SUN4I_INT_CTL_TC) { sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_TC); sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH); complete(&sspi->done); return IRQ_HANDLED; } /* Receive FIFO 3/4 full */ if (status & SUN4I_INT_CTL_RF_F34) { sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH); /* Only clear the interrupt _after_ draining the FIFO */ sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_RF_F34); return IRQ_HANDLED; } /* Transmit FIFO 3/4 empty */ if (status & SUN4I_INT_CTL_TF_E34) { sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH); if (!sspi->len) /* nothing left to transmit */ sun4i_spi_disable_interrupt(sspi, SUN4I_INT_CTL_TF_E34); /* Only clear the interrupt _after_ re-seeding the FIFO */ sun4i_spi_write(sspi, SUN4I_INT_STA_REG, SUN4I_INT_CTL_TF_E34); return IRQ_HANDLED; } return IRQ_NONE; } static int sun4i_spi_runtime_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct sun4i_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; } sun4i_spi_write(sspi, SUN4I_CTL_REG, SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER | SUN4I_CTL_TP); return 0; err: clk_disable_unprepare(sspi->hclk); out: return ret; } static int sun4i_spi_runtime_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct sun4i_spi *sspi = spi_master_get_devdata(master); clk_disable_unprepare(sspi->mclk); clk_disable_unprepare(sspi->hclk); return 0; } static int sun4i_spi_probe(struct platform_device *pdev) { struct spi_master *master; struct sun4i_spi *sspi; struct resource *res; int ret = 0, irq; master = spi_alloc_master(&pdev->dev, sizeof(struct sun4i_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); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); sspi->base_addr = devm_ioremap_resource(&pdev->dev, res); 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) { dev_err(&pdev->dev, "No spi IRQ specified\n"); ret = -ENXIO; goto err_free_master; } ret = devm_request_irq(&pdev->dev, irq, sun4i_spi_handler, 0, "sun4i-spi", sspi); if (ret) { dev_err(&pdev->dev, "Cannot request IRQ\n"); goto err_free_master; } sspi->master = master; master->max_speed_hz = 100 * 1000 * 1000; master->min_speed_hz = 3 * 1000; master->set_cs = sun4i_spi_set_cs; master->transfer_one = sun4i_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 = sun4i_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); /* * This wake-up/shutdown pattern is to be able to have the * device woken up, even if runtime_pm is disabled */ ret = sun4i_spi_runtime_resume(&pdev->dev); if (ret) { dev_err(&pdev->dev, "Couldn't resume the device\n"); goto err_free_master; } pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); pm_runtime_idle(&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); sun4i_spi_runtime_suspend(&pdev->dev); err_free_master: spi_master_put(master); return ret; } static int sun4i_spi_remove(struct platform_device *pdev) { pm_runtime_force_suspend(&pdev->dev); return 0; } static const struct of_device_id sun4i_spi_match[] = { { .compatible = "allwinner,sun4i-a10-spi", }, {} }; MODULE_DEVICE_TABLE(of, sun4i_spi_match); static const struct dev_pm_ops sun4i_spi_pm_ops = { .runtime_resume = sun4i_spi_runtime_resume, .runtime_suspend = sun4i_spi_runtime_suspend, }; static struct platform_driver sun4i_spi_driver = { .probe = sun4i_spi_probe, .remove = sun4i_spi_remove, .driver = { .name = "sun4i-spi", .of_match_table = sun4i_spi_match, .pm = &sun4i_spi_pm_ops, }, }; module_platform_driver(sun4i_spi_driver); MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>"); MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); MODULE_DESCRIPTION("Allwinner A1X/A20 SPI controller driver"); MODULE_LICENSE("GPL");
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