| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Nicolas Ferre | 1854 | 22.88% | 8 | 9.88% |
| Wenyou Yang | 1712 | 21.13% | 6 | 7.41% |
| Cyrille Pitchen | 1258 | 15.53% | 5 | 6.17% |
| Håvard Skinnemoen | 1159 | 14.30% | 6 | 7.41% |
| Grant C. Likely | 521 | 6.43% | 2 | 2.47% |
| Radu Pirea | 366 | 4.52% | 2 | 2.47% |
| Richard Genoud | 261 | 3.22% | 3 | 3.70% |
| David Brownell | 184 | 2.27% | 4 | 4.94% |
| Quentin Schulz | 163 | 2.01% | 2 | 2.47% |
| Szilveszter Ördög | 99 | 1.22% | 1 | 1.23% |
| Atsushi Nemoto | 83 | 1.02% | 1 | 1.23% |
| Jean-Christophe Plagniol-Villard | 74 | 0.91% | 2 | 2.47% |
| Ludovic Desroches | 50 | 0.62% | 2 | 2.47% |
| Jingoo Han | 43 | 0.53% | 2 | 2.47% |
| Emil Goode | 33 | 0.41% | 1 | 1.23% |
| Jean-Christophe Lallemand | 26 | 0.32% | 1 | 1.23% |
| Ben Dooks | 21 | 0.26% | 1 | 1.23% |
| Eugen Hristev | 19 | 0.23% | 1 | 1.23% |
| Kay Sievers | 17 | 0.21% | 2 | 2.47% |
| Axel Lin | 15 | 0.19% | 1 | 1.23% |
| Ben Whitten | 14 | 0.17% | 1 | 1.23% |
| Wei Yongjun | 14 | 0.17% | 1 | 1.23% |
| Mark Brown | 13 | 0.16% | 3 | 3.70% |
| Boris Brezillon | 13 | 0.16% | 1 | 1.23% |
| Alexander Stein | 11 | 0.14% | 1 | 1.23% |
| Stephen Warren | 11 | 0.14% | 1 | 1.23% |
| Alexandre Belloni | 9 | 0.11% | 2 | 2.47% |
| Gerard Kam | 9 | 0.11% | 1 | 1.23% |
| Matthias Brugger | 7 | 0.09% | 1 | 1.23% |
| Nicholas Mc Guire | 7 | 0.09% | 1 | 1.23% |
| Sachin Kamat | 7 | 0.09% | 2 | 2.47% |
| Baruch Siach | 6 | 0.07% | 1 | 1.23% |
| Stefan Agner | 4 | 0.05% | 1 | 1.23% |
| Geert Uytterhoeven | 3 | 0.04% | 2 | 2.47% |
| David Mosberger-Tang | 3 | 0.04% | 1 | 1.23% |
| Randy Dunlap | 3 | 0.04% | 1 | 1.23% |
| Tejun Heo | 3 | 0.04% | 1 | 1.23% |
| Torsten Fleischer | 2 | 0.02% | 1 | 1.23% |
| Vinod Koul | 2 | 0.02% | 1 | 1.23% |
| H Hartley Sweeten | 1 | 0.01% | 1 | 1.23% |
| Jean Delvare | 1 | 0.01% | 1 | 1.23% |
| FUJITA Tomonori | 1 | 0.01% | 1 | 1.23% |
| Fengguang Wu | 1 | 0.01% | 1 | 1.23% |
| Total | 8103 | 81 |
/* * Driver for Atmel AT32 and AT91 SPI Controllers * * Copyright (C) 2006 Atmel Corporation * * 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/kernel.h> #include <linux/clk.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/dmaengine.h> #include <linux/err.h> #include <linux/interrupt.h> #include <linux/spi/spi.h> #include <linux/slab.h> #include <linux/platform_data/dma-atmel.h> #include <linux/of.h> #include <linux/io.h> #include <linux/gpio.h> #include <linux/of_gpio.h> #include <linux/pinctrl/consumer.h> #include <linux/pm_runtime.h> /* SPI register offsets */ #define SPI_CR 0x0000 #define SPI_MR 0x0004 #define SPI_RDR 0x0008 #define SPI_TDR 0x000c #define SPI_SR 0x0010 #define SPI_IER 0x0014 #define SPI_IDR 0x0018 #define SPI_IMR 0x001c #define SPI_CSR0 0x0030 #define SPI_CSR1 0x0034 #define SPI_CSR2 0x0038 #define SPI_CSR3 0x003c #define SPI_FMR 0x0040 #define SPI_FLR 0x0044 #define SPI_VERSION 0x00fc #define SPI_RPR 0x0100 #define SPI_RCR 0x0104 #define SPI_TPR 0x0108 #define SPI_TCR 0x010c #define SPI_RNPR 0x0110 #define SPI_RNCR 0x0114 #define SPI_TNPR 0x0118 #define SPI_TNCR 0x011c #define SPI_PTCR 0x0120 #define SPI_PTSR 0x0124 /* Bitfields in CR */ #define SPI_SPIEN_OFFSET 0 #define SPI_SPIEN_SIZE 1 #define SPI_SPIDIS_OFFSET 1 #define SPI_SPIDIS_SIZE 1 #define SPI_SWRST_OFFSET 7 #define SPI_SWRST_SIZE 1 #define SPI_LASTXFER_OFFSET 24 #define SPI_LASTXFER_SIZE 1 #define SPI_TXFCLR_OFFSET 16 #define SPI_TXFCLR_SIZE 1 #define SPI_RXFCLR_OFFSET 17 #define SPI_RXFCLR_SIZE 1 #define SPI_FIFOEN_OFFSET 30 #define SPI_FIFOEN_SIZE 1 #define SPI_FIFODIS_OFFSET 31 #define SPI_FIFODIS_SIZE 1 /* Bitfields in MR */ #define SPI_MSTR_OFFSET 0 #define SPI_MSTR_SIZE 1 #define SPI_PS_OFFSET 1 #define SPI_PS_SIZE 1 #define SPI_PCSDEC_OFFSET 2 #define SPI_PCSDEC_SIZE 1 #define SPI_FDIV_OFFSET 3 #define SPI_FDIV_SIZE 1 #define SPI_MODFDIS_OFFSET 4 #define SPI_MODFDIS_SIZE 1 #define SPI_WDRBT_OFFSET 5 #define SPI_WDRBT_SIZE 1 #define SPI_LLB_OFFSET 7 #define SPI_LLB_SIZE 1 #define SPI_PCS_OFFSET 16 #define SPI_PCS_SIZE 4 #define SPI_DLYBCS_OFFSET 24 #define SPI_DLYBCS_SIZE 8 /* Bitfields in RDR */ #define SPI_RD_OFFSET 0 #define SPI_RD_SIZE 16 /* Bitfields in TDR */ #define SPI_TD_OFFSET 0 #define SPI_TD_SIZE 16 /* Bitfields in SR */ #define SPI_RDRF_OFFSET 0 #define SPI_RDRF_SIZE 1 #define SPI_TDRE_OFFSET 1 #define SPI_TDRE_SIZE 1 #define SPI_MODF_OFFSET 2 #define SPI_MODF_SIZE 1 #define SPI_OVRES_OFFSET 3 #define SPI_OVRES_SIZE 1 #define SPI_ENDRX_OFFSET 4 #define SPI_ENDRX_SIZE 1 #define SPI_ENDTX_OFFSET 5 #define SPI_ENDTX_SIZE 1 #define SPI_RXBUFF_OFFSET 6 #define SPI_RXBUFF_SIZE 1 #define SPI_TXBUFE_OFFSET 7 #define SPI_TXBUFE_SIZE 1 #define SPI_NSSR_OFFSET 8 #define SPI_NSSR_SIZE 1 #define SPI_TXEMPTY_OFFSET 9 #define SPI_TXEMPTY_SIZE 1 #define SPI_SPIENS_OFFSET 16 #define SPI_SPIENS_SIZE 1 #define SPI_TXFEF_OFFSET 24 #define SPI_TXFEF_SIZE 1 #define SPI_TXFFF_OFFSET 25 #define SPI_TXFFF_SIZE 1 #define SPI_TXFTHF_OFFSET 26 #define SPI_TXFTHF_SIZE 1 #define SPI_RXFEF_OFFSET 27 #define SPI_RXFEF_SIZE 1 #define SPI_RXFFF_OFFSET 28 #define SPI_RXFFF_SIZE 1 #define SPI_RXFTHF_OFFSET 29 #define SPI_RXFTHF_SIZE 1 #define SPI_TXFPTEF_OFFSET 30 #define SPI_TXFPTEF_SIZE 1 #define SPI_RXFPTEF_OFFSET 31 #define SPI_RXFPTEF_SIZE 1 /* Bitfields in CSR0 */ #define SPI_CPOL_OFFSET 0 #define SPI_CPOL_SIZE 1 #define SPI_NCPHA_OFFSET 1 #define SPI_NCPHA_SIZE 1 #define SPI_CSAAT_OFFSET 3 #define SPI_CSAAT_SIZE 1 #define SPI_BITS_OFFSET 4 #define SPI_BITS_SIZE 4 #define SPI_SCBR_OFFSET 8 #define SPI_SCBR_SIZE 8 #define SPI_DLYBS_OFFSET 16 #define SPI_DLYBS_SIZE 8 #define SPI_DLYBCT_OFFSET 24 #define SPI_DLYBCT_SIZE 8 /* Bitfields in RCR */ #define SPI_RXCTR_OFFSET 0 #define SPI_RXCTR_SIZE 16 /* Bitfields in TCR */ #define SPI_TXCTR_OFFSET 0 #define SPI_TXCTR_SIZE 16 /* Bitfields in RNCR */ #define SPI_RXNCR_OFFSET 0 #define SPI_RXNCR_SIZE 16 /* Bitfields in TNCR */ #define SPI_TXNCR_OFFSET 0 #define SPI_TXNCR_SIZE 16 /* Bitfields in PTCR */ #define SPI_RXTEN_OFFSET 0 #define SPI_RXTEN_SIZE 1 #define SPI_RXTDIS_OFFSET 1 #define SPI_RXTDIS_SIZE 1 #define SPI_TXTEN_OFFSET 8 #define SPI_TXTEN_SIZE 1 #define SPI_TXTDIS_OFFSET 9 #define SPI_TXTDIS_SIZE 1 /* Bitfields in FMR */ #define SPI_TXRDYM_OFFSET 0 #define SPI_TXRDYM_SIZE 2 #define SPI_RXRDYM_OFFSET 4 #define SPI_RXRDYM_SIZE 2 #define SPI_TXFTHRES_OFFSET 16 #define SPI_TXFTHRES_SIZE 6 #define SPI_RXFTHRES_OFFSET 24 #define SPI_RXFTHRES_SIZE 6 /* Bitfields in FLR */ #define SPI_TXFL_OFFSET 0 #define SPI_TXFL_SIZE 6 #define SPI_RXFL_OFFSET 16 #define SPI_RXFL_SIZE 6 /* Constants for BITS */ #define SPI_BITS_8_BPT 0 #define SPI_BITS_9_BPT 1 #define SPI_BITS_10_BPT 2 #define SPI_BITS_11_BPT 3 #define SPI_BITS_12_BPT 4 #define SPI_BITS_13_BPT 5 #define SPI_BITS_14_BPT 6 #define SPI_BITS_15_BPT 7 #define SPI_BITS_16_BPT 8 #define SPI_ONE_DATA 0 #define SPI_TWO_DATA 1 #define SPI_FOUR_DATA 2 /* Bit manipulation macros */ #define SPI_BIT(name) \ (1 << SPI_##name##_OFFSET) #define SPI_BF(name, value) \ (((value) & ((1 << SPI_##name##_SIZE) - 1)) << SPI_##name##_OFFSET) #define SPI_BFEXT(name, value) \ (((value) >> SPI_##name##_OFFSET) & ((1 << SPI_##name##_SIZE) - 1)) #define SPI_BFINS(name, value, old) \ (((old) & ~(((1 << SPI_##name##_SIZE) - 1) << SPI_##name##_OFFSET)) \ | SPI_BF(name, value)) /* Register access macros */ #ifdef CONFIG_AVR32 #define spi_readl(port, reg) \ __raw_readl((port)->regs + SPI_##reg) #define spi_writel(port, reg, value) \ __raw_writel((value), (port)->regs + SPI_##reg) #define spi_readw(port, reg) \ __raw_readw((port)->regs + SPI_##reg) #define spi_writew(port, reg, value) \ __raw_writew((value), (port)->regs + SPI_##reg) #define spi_readb(port, reg) \ __raw_readb((port)->regs + SPI_##reg) #define spi_writeb(port, reg, value) \ __raw_writeb((value), (port)->regs + SPI_##reg) #else #define spi_readl(port, reg) \ readl_relaxed((port)->regs + SPI_##reg) #define spi_writel(port, reg, value) \ writel_relaxed((value), (port)->regs + SPI_##reg) #define spi_readw(port, reg) \ readw_relaxed((port)->regs + SPI_##reg) #define spi_writew(port, reg, value) \ writew_relaxed((value), (port)->regs + SPI_##reg) #define spi_readb(port, reg) \ readb_relaxed((port)->regs + SPI_##reg) #define spi_writeb(port, reg, value) \ writeb_relaxed((value), (port)->regs + SPI_##reg) #endif /* use PIO for small transfers, avoiding DMA setup/teardown overhead and * cache operations; better heuristics consider wordsize and bitrate. */ #define DMA_MIN_BYTES 16 #define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) #define AUTOSUSPEND_TIMEOUT 2000 struct atmel_spi_caps { bool is_spi2; bool has_wdrbt; bool has_dma_support; bool has_pdc_support; }; /* * The core SPI transfer engine just talks to a register bank to set up * DMA transfers; transfer queue progress is driven by IRQs. The clock * framework provides the base clock, subdivided for each spi_device. */ struct atmel_spi { spinlock_t lock; unsigned long flags; phys_addr_t phybase; void __iomem *regs; int irq; struct clk *clk; struct platform_device *pdev; unsigned long spi_clk; struct spi_transfer *current_transfer; int current_remaining_bytes; int done_status; dma_addr_t dma_addr_rx_bbuf; dma_addr_t dma_addr_tx_bbuf; void *addr_rx_bbuf; void *addr_tx_bbuf; struct completion xfer_completion; struct atmel_spi_caps caps; bool use_dma; bool use_pdc; bool use_cs_gpios; bool keep_cs; bool cs_active; u32 fifo_size; }; /* Controller-specific per-slave state */ struct atmel_spi_device { unsigned int npcs_pin; u32 csr; }; #define SPI_MAX_DMA_XFER 65535 /* true for both PDC and DMA */ #define INVALID_DMA_ADDRESS 0xffffffff /* * Version 2 of the SPI controller has * - CR.LASTXFER * - SPI_MR.DIV32 may become FDIV or must-be-zero (here: always zero) * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) * - SPI_CSRx.CSAAT * - SPI_CSRx.SBCR allows faster clocking */ static bool atmel_spi_is_v2(struct atmel_spi *as) { return as->caps.is_spi2; } /* * Earlier SPI controllers (e.g. on at91rm9200) have a design bug whereby * they assume that spi slave device state will not change on deselect, so * that automagic deselection is OK. ("NPCSx rises if no data is to be * transmitted") Not so! Workaround uses nCSx pins as GPIOs; or newer * controllers have CSAAT and friends. * * Since the CSAAT functionality is a bit weird on newer controllers as * well, we use GPIO to control nCSx pins on all controllers, updating * MR.PCS to avoid confusing the controller. Using GPIOs also lets us * support active-high chipselects despite the controller's belief that * only active-low devices/systems exists. * * However, at91rm9200 has a second erratum whereby nCS0 doesn't work * right when driven with GPIO. ("Mode Fault does not allow more than one * Master on Chip Select 0.") No workaround exists for that ... so for * nCS0 on that chip, we (a) don't use the GPIO, (b) can't support CS_HIGH, * and (c) will trigger that first erratum in some cases. */ static void cs_activate(struct atmel_spi *as, struct spi_device *spi) { struct atmel_spi_device *asd = spi->controller_state; unsigned active = spi->mode & SPI_CS_HIGH; u32 mr; if (atmel_spi_is_v2(as)) { spi_writel(as, CSR0 + 4 * spi->chip_select, asd->csr); /* For the low SPI version, there is a issue that PDC transfer * on CS1,2,3 needs SPI_CSR0.BITS config as SPI_CSR1,2,3.BITS */ spi_writel(as, CSR0, asd->csr); if (as->caps.has_wdrbt) { spi_writel(as, MR, SPI_BF(PCS, ~(0x01 << spi->chip_select)) | SPI_BIT(WDRBT) | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); } else { spi_writel(as, MR, SPI_BF(PCS, ~(0x01 << spi->chip_select)) | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); } mr = spi_readl(as, MR); if (as->use_cs_gpios) gpio_set_value(asd->npcs_pin, active); } else { u32 cpol = (spi->mode & SPI_CPOL) ? SPI_BIT(CPOL) : 0; int i; u32 csr; /* Make sure clock polarity is correct */ for (i = 0; i < spi->master->num_chipselect; i++) { csr = spi_readl(as, CSR0 + 4 * i); if ((csr ^ cpol) & SPI_BIT(CPOL)) spi_writel(as, CSR0 + 4 * i, csr ^ SPI_BIT(CPOL)); } mr = spi_readl(as, MR); mr = SPI_BFINS(PCS, ~(1 << spi->chip_select), mr); if (as->use_cs_gpios && spi->chip_select != 0) gpio_set_value(asd->npcs_pin, active); spi_writel(as, MR, mr); } dev_dbg(&spi->dev, "activate %u%s, mr %08x\n", asd->npcs_pin, active ? " (high)" : "", mr); } static void cs_deactivate(struct atmel_spi *as, struct spi_device *spi) { struct atmel_spi_device *asd = spi->controller_state; unsigned active = spi->mode & SPI_CS_HIGH; u32 mr; /* only deactivate *this* device; sometimes transfers to * another device may be active when this routine is called. */ mr = spi_readl(as, MR); if (~SPI_BFEXT(PCS, mr) & (1 << spi->chip_select)) { mr = SPI_BFINS(PCS, 0xf, mr); spi_writel(as, MR, mr); } dev_dbg(&spi->dev, "DEactivate %u%s, mr %08x\n", asd->npcs_pin, active ? " (low)" : "", mr); if (!as->use_cs_gpios) spi_writel(as, CR, SPI_BIT(LASTXFER)); else if (atmel_spi_is_v2(as) || spi->chip_select != 0) gpio_set_value(asd->npcs_pin, !active); } static void atmel_spi_lock(struct atmel_spi *as) __acquires(&as->lock) { spin_lock_irqsave(&as->lock, as->flags); } static void atmel_spi_unlock(struct atmel_spi *as) __releases(&as->lock) { spin_unlock_irqrestore(&as->lock, as->flags); } static inline bool atmel_spi_is_vmalloc_xfer(struct spi_transfer *xfer) { return is_vmalloc_addr(xfer->tx_buf) || is_vmalloc_addr(xfer->rx_buf); } static inline bool atmel_spi_use_dma(struct atmel_spi *as, struct spi_transfer *xfer) { return as->use_dma && xfer->len >= DMA_MIN_BYTES; } static bool atmel_spi_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { struct atmel_spi *as = spi_master_get_devdata(master); if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) return atmel_spi_use_dma(as, xfer) && !atmel_spi_is_vmalloc_xfer(xfer); else return atmel_spi_use_dma(as, xfer); } static int atmel_spi_dma_slave_config(struct atmel_spi *as, struct dma_slave_config *slave_config, u8 bits_per_word) { struct spi_master *master = platform_get_drvdata(as->pdev); int err = 0; if (bits_per_word > 8) { slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; } else { slave_config->dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; slave_config->src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; } slave_config->dst_addr = (dma_addr_t)as->phybase + SPI_TDR; slave_config->src_addr = (dma_addr_t)as->phybase + SPI_RDR; slave_config->src_maxburst = 1; slave_config->dst_maxburst = 1; slave_config->device_fc = false; /* * This driver uses fixed peripheral select mode (PS bit set to '0' in * the Mode Register). * So according to the datasheet, when FIFOs are available (and * enabled), the Transmit FIFO operates in Multiple Data Mode. * In this mode, up to 2 data, not 4, can be written into the Transmit * Data Register in a single access. * However, the first data has to be written into the lowest 16 bits and * the second data into the highest 16 bits of the Transmit * Data Register. For 8bit data (the most frequent case), it would * require to rework tx_buf so each data would actualy fit 16 bits. * So we'd rather write only one data at the time. Hence the transmit * path works the same whether FIFOs are available (and enabled) or not. */ slave_config->direction = DMA_MEM_TO_DEV; if (dmaengine_slave_config(master->dma_tx, slave_config)) { dev_err(&as->pdev->dev, "failed to configure tx dma channel\n"); err = -EINVAL; } /* * This driver configures the spi controller for master mode (MSTR bit * set to '1' in the Mode Register). * So according to the datasheet, when FIFOs are available (and * enabled), the Receive FIFO operates in Single Data Mode. * So the receive path works the same whether FIFOs are available (and * enabled) or not. */ slave_config->direction = DMA_DEV_TO_MEM; if (dmaengine_slave_config(master->dma_rx, slave_config)) { dev_err(&as->pdev->dev, "failed to configure rx dma channel\n"); err = -EINVAL; } return err; } static int atmel_spi_configure_dma(struct spi_master *master, struct atmel_spi *as) { struct dma_slave_config slave_config; struct device *dev = &as->pdev->dev; int err; dma_cap_mask_t mask; dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); master->dma_tx = dma_request_slave_channel_reason(dev, "tx"); if (IS_ERR(master->dma_tx)) { err = PTR_ERR(master->dma_tx); if (err == -EPROBE_DEFER) { dev_warn(dev, "no DMA channel available at the moment\n"); goto error_clear; } dev_err(dev, "DMA TX channel not available, SPI unable to use DMA\n"); err = -EBUSY; goto error_clear; } /* * No reason to check EPROBE_DEFER here since we have already requested * tx channel. If it fails here, it's for another reason. */ master->dma_rx = dma_request_slave_channel(dev, "rx"); if (!master->dma_rx) { dev_err(dev, "DMA RX channel not available, SPI unable to use DMA\n"); err = -EBUSY; goto error; } err = atmel_spi_dma_slave_config(as, &slave_config, 8); if (err) goto error; dev_info(&as->pdev->dev, "Using %s (tx) and %s (rx) for DMA transfers\n", dma_chan_name(master->dma_tx), dma_chan_name(master->dma_rx)); return 0; error: if (master->dma_rx) dma_release_channel(master->dma_rx); if (!IS_ERR(master->dma_tx)) dma_release_channel(master->dma_tx); error_clear: master->dma_tx = master->dma_rx = NULL; return err; } static void atmel_spi_stop_dma(struct spi_master *master) { if (master->dma_rx) dmaengine_terminate_all(master->dma_rx); if (master->dma_tx) dmaengine_terminate_all(master->dma_tx); } static void atmel_spi_release_dma(struct spi_master *master) { if (master->dma_rx) { dma_release_channel(master->dma_rx); master->dma_rx = NULL; } if (master->dma_tx) { dma_release_channel(master->dma_tx); master->dma_tx = NULL; } } /* This function is called by the DMA driver from tasklet context */ static void dma_callback(void *data) { struct spi_master *master = data; struct atmel_spi *as = spi_master_get_devdata(master); if (is_vmalloc_addr(as->current_transfer->rx_buf) && IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) { memcpy(as->current_transfer->rx_buf, as->addr_rx_bbuf, as->current_transfer->len); } complete(&as->xfer_completion); } /* * Next transfer using PIO without FIFO. */ static void atmel_spi_next_xfer_single(struct spi_master *master, struct spi_transfer *xfer) { struct atmel_spi *as = spi_master_get_devdata(master); unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_pio\n"); /* Make sure data is not remaining in RDR */ spi_readl(as, RDR); while (spi_readl(as, SR) & SPI_BIT(RDRF)) { spi_readl(as, RDR); cpu_relax(); } if (xfer->bits_per_word > 8) spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos)); else spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos)); dev_dbg(master->dev.parent, " start pio xfer %p: len %u tx %p rx %p bitpw %d\n", xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, xfer->bits_per_word); /* Enable relevant interrupts */ spi_writel(as, IER, SPI_BIT(RDRF) | SPI_BIT(OVRES)); } /* * Next transfer using PIO with FIFO. */ static void atmel_spi_next_xfer_fifo(struct spi_master *master, struct spi_transfer *xfer) { struct atmel_spi *as = spi_master_get_devdata(master); u32 current_remaining_data, num_data; u32 offset = xfer->len - as->current_remaining_bytes; const u16 *words = (const u16 *)((u8 *)xfer->tx_buf + offset); const u8 *bytes = (const u8 *)((u8 *)xfer->tx_buf + offset); u16 td0, td1; u32 fifomr; dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_fifo\n"); /* Compute the number of data to transfer in the current iteration */ current_remaining_data = ((xfer->bits_per_word > 8) ? ((u32)as->current_remaining_bytes >> 1) : (u32)as->current_remaining_bytes); num_data = min(current_remaining_data, as->fifo_size); /* Flush RX and TX FIFOs */ spi_writel(as, CR, SPI_BIT(RXFCLR) | SPI_BIT(TXFCLR)); while (spi_readl(as, FLR)) cpu_relax(); /* Set RX FIFO Threshold to the number of data to transfer */ fifomr = spi_readl(as, FMR); spi_writel(as, FMR, SPI_BFINS(RXFTHRES, num_data, fifomr)); /* Clear FIFO flags in the Status Register, especially RXFTHF */ (void)spi_readl(as, SR); /* Fill TX FIFO */ while (num_data >= 2) { if (xfer->bits_per_word > 8) { td0 = *words++; td1 = *words++; } else { td0 = *bytes++; td1 = *bytes++; } spi_writel(as, TDR, (td1 << 16) | td0); num_data -= 2; } if (num_data) { if (xfer->bits_per_word > 8) td0 = *words++; else td0 = *bytes++; spi_writew(as, TDR, td0); num_data--; } dev_dbg(master->dev.parent, " start fifo xfer %p: len %u tx %p rx %p bitpw %d\n", xfer, xfer->len, xfer->tx_buf, xfer->rx_buf, xfer->bits_per_word); /* * Enable RX FIFO Threshold Flag interrupt to be notified about * transfer completion. */ spi_writel(as, IER, SPI_BIT(RXFTHF) | SPI_BIT(OVRES)); } /* * Next transfer using PIO. */ static void atmel_spi_next_xfer_pio(struct spi_master *master, struct spi_transfer *xfer) { struct atmel_spi *as = spi_master_get_devdata(master); if (as->fifo_size) atmel_spi_next_xfer_fifo(master, xfer); else atmel_spi_next_xfer_single(master, xfer); } /* * Submit next transfer for DMA. */ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master, struct spi_transfer *xfer, u32 *plen) { struct atmel_spi *as = spi_master_get_devdata(master); struct dma_chan *rxchan = master->dma_rx; struct dma_chan *txchan = master->dma_tx; struct dma_async_tx_descriptor *rxdesc; struct dma_async_tx_descriptor *txdesc; struct dma_slave_config slave_config; dma_cookie_t cookie; dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n"); /* Check that the channels are available */ if (!rxchan || !txchan) return -ENODEV; /* release lock for DMA operations */ atmel_spi_unlock(as); *plen = xfer->len; if (atmel_spi_dma_slave_config(as, &slave_config, xfer->bits_per_word)) goto err_exit; /* Send both scatterlists */ if (atmel_spi_is_vmalloc_xfer(xfer) && IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) { rxdesc = dmaengine_prep_slave_single(rxchan, as->dma_addr_rx_bbuf, xfer->len, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); } else { rxdesc = dmaengine_prep_slave_sg(rxchan, xfer->rx_sg.sgl, xfer->rx_sg.nents, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); } if (!rxdesc) goto err_dma; if (atmel_spi_is_vmalloc_xfer(xfer) && IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) { memcpy(as->addr_tx_bbuf, xfer->tx_buf, xfer->len); txdesc = dmaengine_prep_slave_single(txchan, as->dma_addr_tx_bbuf, xfer->len, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); } else { txdesc = dmaengine_prep_slave_sg(txchan, xfer->tx_sg.sgl, xfer->tx_sg.nents, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); } if (!txdesc) goto err_dma; dev_dbg(master->dev.parent, " start dma xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", xfer, xfer->len, xfer->tx_buf, (unsigned long long)xfer->tx_dma, xfer->rx_buf, (unsigned long long)xfer->rx_dma); /* Enable relevant interrupts */ spi_writel(as, IER, SPI_BIT(OVRES)); /* Put the callback on the RX transfer only, that should finish last */ rxdesc->callback = dma_callback; rxdesc->callback_param = master; /* Submit and fire RX and TX with TX last so we're ready to read! */ cookie = rxdesc->tx_submit(rxdesc); if (dma_submit_error(cookie)) goto err_dma; cookie = txdesc->tx_submit(txdesc); if (dma_submit_error(cookie)) goto err_dma; rxchan->device->device_issue_pending(rxchan); txchan->device->device_issue_pending(txchan); /* take back lock */ atmel_spi_lock(as); return 0; err_dma: spi_writel(as, IDR, SPI_BIT(OVRES)); atmel_spi_stop_dma(master); err_exit: atmel_spi_lock(as); return -ENOMEM; } static void atmel_spi_next_xfer_data(struct spi_master *master, struct spi_transfer *xfer, dma_addr_t *tx_dma, dma_addr_t *rx_dma, u32 *plen) { *rx_dma = xfer->rx_dma + xfer->len - *plen; *tx_dma = xfer->tx_dma + xfer->len - *plen; if (*plen > master->max_dma_len) *plen = master->max_dma_len; } static int atmel_spi_set_xfer_speed(struct atmel_spi *as, struct spi_device *spi, struct spi_transfer *xfer) { u32 scbr, csr; unsigned long bus_hz; /* v1 chips start out at half the peripheral bus speed. */ bus_hz = as->spi_clk; if (!atmel_spi_is_v2(as)) bus_hz /= 2; /* * Calculate the lowest divider that satisfies the * constraint, assuming div32/fdiv/mbz == 0. */ scbr = DIV_ROUND_UP(bus_hz, xfer->speed_hz); /* * If the resulting divider doesn't fit into the * register bitfield, we can't satisfy the constraint. */ if (scbr >= (1 << SPI_SCBR_SIZE)) { dev_err(&spi->dev, "setup: %d Hz too slow, scbr %u; min %ld Hz\n", xfer->speed_hz, scbr, bus_hz/255); return -EINVAL; } if (scbr == 0) { dev_err(&spi->dev, "setup: %d Hz too high, scbr %u; max %ld Hz\n", xfer->speed_hz, scbr, bus_hz); return -EINVAL; } csr = spi_readl(as, CSR0 + 4 * spi->chip_select); csr = SPI_BFINS(SCBR, scbr, csr); spi_writel(as, CSR0 + 4 * spi->chip_select, csr); return 0; } /* * Submit next transfer for PDC. * lock is held, spi irq is blocked */ static void atmel_spi_pdc_next_xfer(struct spi_master *master, struct spi_message *msg, struct spi_transfer *xfer) { struct atmel_spi *as = spi_master_get_devdata(master); u32 len; dma_addr_t tx_dma, rx_dma; spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); len = as->current_remaining_bytes; atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); as->current_remaining_bytes -= len; spi_writel(as, RPR, rx_dma); spi_writel(as, TPR, tx_dma); if (msg->spi->bits_per_word > 8) len >>= 1; spi_writel(as, RCR, len); spi_writel(as, TCR, len); dev_dbg(&msg->spi->dev, " start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", xfer, xfer->len, xfer->tx_buf, (unsigned long long)xfer->tx_dma, xfer->rx_buf, (unsigned long long)xfer->rx_dma); if (as->current_remaining_bytes) { len = as->current_remaining_bytes; atmel_spi_next_xfer_data(master, xfer, &tx_dma, &rx_dma, &len); as->current_remaining_bytes -= len; spi_writel(as, RNPR, rx_dma); spi_writel(as, TNPR, tx_dma); if (msg->spi->bits_per_word > 8) len >>= 1; spi_writel(as, RNCR, len); spi_writel(as, TNCR, len); dev_dbg(&msg->spi->dev, " next xfer %p: len %u tx %p/%08llx rx %p/%08llx\n", xfer, xfer->len, xfer->tx_buf, (unsigned long long)xfer->tx_dma, xfer->rx_buf, (unsigned long long)xfer->rx_dma); } /* REVISIT: We're waiting for RXBUFF before we start the next * transfer because we need to handle some difficult timing * issues otherwise. If we wait for TXBUFE in one transfer and * then starts waiting for RXBUFF in the next, it's difficult * to tell the difference between the RXBUFF interrupt we're * actually waiting for and the RXBUFF interrupt of the * previous transfer. * * It should be doable, though. Just not now... */ spi_writel(as, IER, SPI_BIT(RXBUFF) | SPI_BIT(OVRES)); spi_writel(as, PTCR, SPI_BIT(TXTEN) | SPI_BIT(RXTEN)); } /* * For DMA, tx_buf/tx_dma have the same relationship as rx_buf/rx_dma: * - The buffer is either valid for CPU access, else NULL * - If the buffer is valid, so is its DMA address * * This driver manages the dma address unless message->is_dma_mapped. */ static int atmel_spi_dma_map_xfer(struct atmel_spi *as, struct spi_transfer *xfer) { struct device *dev = &as->pdev->dev; xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS; if (xfer->tx_buf) { /* tx_buf is a const void* where we need a void * for the dma * mapping */ void *nonconst_tx = (void *)xfer->tx_buf; xfer->tx_dma = dma_map_single(dev, nonconst_tx, xfer->len, DMA_TO_DEVICE); if (dma_mapping_error(dev, xfer->tx_dma)) return -ENOMEM; } if (xfer->rx_buf) { xfer->rx_dma = dma_map_single(dev, xfer->rx_buf, xfer->len, DMA_FROM_DEVICE); if (dma_mapping_error(dev, xfer->rx_dma)) { if (xfer->tx_buf) dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE); return -ENOMEM; } } return 0; } static void atmel_spi_dma_unmap_xfer(struct spi_master *master, struct spi_transfer *xfer) { if (xfer->tx_dma != INVALID_DMA_ADDRESS) dma_unmap_single(master->dev.parent, xfer->tx_dma, xfer->len, DMA_TO_DEVICE); if (xfer->rx_dma != INVALID_DMA_ADDRESS) dma_unmap_single(master->dev.parent, xfer->rx_dma, xfer->len, DMA_FROM_DEVICE); } static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as) { spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); } static void atmel_spi_pump_single_data(struct atmel_spi *as, struct spi_transfer *xfer) { u8 *rxp; u16 *rxp16; unsigned long xfer_pos = xfer->len - as->current_remaining_bytes; if (xfer->bits_per_word > 8) { rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos); *rxp16 = spi_readl(as, RDR); } else { rxp = ((u8 *)xfer->rx_buf) + xfer_pos; *rxp = spi_readl(as, RDR); } if (xfer->bits_per_word > 8) { if (as->current_remaining_bytes > 2) as->current_remaining_bytes -= 2; else as->current_remaining_bytes = 0; } else { as->current_remaining_bytes--; } } static void atmel_spi_pump_fifo_data(struct atmel_spi *as, struct spi_transfer *xfer) { u32 fifolr = spi_readl(as, FLR); u32 num_bytes, num_data = SPI_BFEXT(RXFL, fifolr); u32 offset = xfer->len - as->current_remaining_bytes; u16 *words = (u16 *)((u8 *)xfer->rx_buf + offset); u8 *bytes = (u8 *)((u8 *)xfer->rx_buf + offset); u16 rd; /* RD field is the lowest 16 bits of RDR */ /* Update the number of remaining bytes to transfer */ num_bytes = ((xfer->bits_per_word > 8) ? (num_data << 1) : num_data); if (as->current_remaining_bytes > num_bytes) as->current_remaining_bytes -= num_bytes; else as->current_remaining_bytes = 0; /* Handle odd number of bytes when data are more than 8bit width */ if (xfer->bits_per_word > 8) as->current_remaining_bytes &= ~0x1; /* Read data */ while (num_data) { rd = spi_readl(as, RDR); if (xfer->bits_per_word > 8) *words++ = rd; else *bytes++ = rd; num_data--; } } /* Called from IRQ * * Must update "current_remaining_bytes" to keep track of data * to transfer. */ static void atmel_spi_pump_pio_data(struct atmel_spi *as, struct spi_transfer *xfer) { if (as->fifo_size) atmel_spi_pump_fifo_data(as, xfer); else atmel_spi_pump_single_data(as, xfer); } /* Interrupt * * No need for locking in this Interrupt handler: done_status is the * only information modified. */ static irqreturn_t atmel_spi_pio_interrupt(int irq, void *dev_id) { struct spi_master *master = dev_id; struct atmel_spi *as = spi_master_get_devdata(master); u32 status, pending, imr; struct spi_transfer *xfer; int ret = IRQ_NONE; imr = spi_readl(as, IMR); status = spi_readl(as, SR); pending = status & imr; if (pending & SPI_BIT(OVRES)) { ret = IRQ_HANDLED; spi_writel(as, IDR, SPI_BIT(OVRES)); dev_warn(master->dev.parent, "overrun\n"); /* * When we get an overrun, we disregard the current * transfer. Data will not be copied back from any * bounce buffer and msg->actual_len will not be * updated with the last xfer. * * We will also not process any remaning transfers in * the message. */ as->done_status = -EIO; smp_wmb(); /* Clear any overrun happening while cleaning up */ spi_readl(as, SR); complete(&as->xfer_completion); } else if (pending & (SPI_BIT(RDRF) | SPI_BIT(RXFTHF))) { atmel_spi_lock(as); if (as->current_remaining_bytes) { ret = IRQ_HANDLED; xfer = as->current_transfer; atmel_spi_pump_pio_data(as, xfer); if (!as->current_remaining_bytes) spi_writel(as, IDR, pending); complete(&as->xfer_completion); } atmel_spi_unlock(as); } else { WARN_ONCE(pending, "IRQ not handled, pending = %x\n", pending); ret = IRQ_HANDLED; spi_writel(as, IDR, pending); } return ret; } static irqreturn_t atmel_spi_pdc_interrupt(int irq, void *dev_id) { struct spi_master *master = dev_id; struct atmel_spi *as = spi_master_get_devdata(master); u32 status, pending, imr; int ret = IRQ_NONE; imr = spi_readl(as, IMR); status = spi_readl(as, SR); pending = status & imr; if (pending & SPI_BIT(OVRES)) { ret = IRQ_HANDLED; spi_writel(as, IDR, (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX) | SPI_BIT(OVRES))); /* Clear any overrun happening while cleaning up */ spi_readl(as, SR); as->done_status = -EIO; complete(&as->xfer_completion); } else if (pending & (SPI_BIT(RXBUFF) | SPI_BIT(ENDRX))) { ret = IRQ_HANDLED; spi_writel(as, IDR, pending); complete(&as->xfer_completion); } return ret; } static int atmel_spi_setup(struct spi_device *spi) { struct atmel_spi *as; struct atmel_spi_device *asd; u32 csr; unsigned int bits = spi->bits_per_word; unsigned int npcs_pin; as = spi_master_get_devdata(spi->master); /* see notes above re chipselect */ if (!atmel_spi_is_v2(as) && spi->chip_select == 0 && (spi->mode & SPI_CS_HIGH)) { dev_dbg(&spi->dev, "setup: can't be active-high\n"); return -EINVAL; } csr = SPI_BF(BITS, bits - 8); if (spi->mode & SPI_CPOL) csr |= SPI_BIT(CPOL); if (!(spi->mode & SPI_CPHA)) csr |= SPI_BIT(NCPHA); if (!as->use_cs_gpios) csr |= SPI_BIT(CSAAT); /* DLYBS is mostly irrelevant since we manage chipselect using GPIOs. * * DLYBCT would add delays between words, slowing down transfers. * It could potentially be useful to cope with DMA bottlenecks, but * in those cases it's probably best to just use a lower bitrate. */ csr |= SPI_BF(DLYBS, 0); csr |= SPI_BF(DLYBCT, 0); /* chipselect must have been muxed as GPIO (e.g. in board setup) */ npcs_pin = (unsigned long)spi->controller_data; if (!as->use_cs_gpios) npcs_pin = spi->chip_select; else if (gpio_is_valid(spi->cs_gpio)) npcs_pin = spi->cs_gpio; asd = spi->controller_state; if (!asd) { asd = kzalloc(sizeof(struct atmel_spi_device), GFP_KERNEL); if (!asd) return -ENOMEM; if (as->use_cs_gpios) gpio_direction_output(npcs_pin, !(spi->mode & SPI_CS_HIGH)); asd->npcs_pin = npcs_pin; spi->controller_state = asd; } asd->csr = csr; dev_dbg(&spi->dev, "setup: bpw %u mode 0x%x -> csr%d %08x\n", bits, spi->mode, spi->chip_select, csr); if (!atmel_spi_is_v2(as)) spi_writel(as, CSR0 + 4 * spi->chip_select, csr); return 0; } static int atmel_spi_one_transfer(struct spi_master *master, struct spi_message *msg, struct spi_transfer *xfer) { struct atmel_spi *as; struct spi_device *spi = msg->spi; u8 bits; u32 len; struct atmel_spi_device *asd; int timeout; int ret; unsigned long dma_timeout; as = spi_master_get_devdata(master); if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) { dev_dbg(&spi->dev, "missing rx or tx buf\n"); return -EINVAL; } asd = spi->controller_state; bits = (asd->csr >> 4) & 0xf; if (bits != xfer->bits_per_word - 8) { dev_dbg(&spi->dev, "you can't yet change bits_per_word in transfers\n"); return -ENOPROTOOPT; } /* * DMA map early, for performance (empties dcache ASAP) and * better fault reporting. */ if ((!msg->is_dma_mapped) && as->use_pdc) { if (atmel_spi_dma_map_xfer(as, xfer) < 0) return -ENOMEM; } atmel_spi_set_xfer_speed(as, msg->spi, xfer); as->done_status = 0; as->current_transfer = xfer; as->current_remaining_bytes = xfer->len; while (as->current_remaining_bytes) { reinit_completion(&as->xfer_completion); if (as->use_pdc) { atmel_spi_pdc_next_xfer(master, msg, xfer); } else if (atmel_spi_use_dma(as, xfer)) { len = as->current_remaining_bytes; ret = atmel_spi_next_xfer_dma_submit(master, xfer, &len); if (ret) { dev_err(&spi->dev, "unable to use DMA, fallback to PIO\n"); atmel_spi_next_xfer_pio(master, xfer); } else { as->current_remaining_bytes -= len; if (as->current_remaining_bytes < 0) as->current_remaining_bytes = 0; } } else { atmel_spi_next_xfer_pio(master, xfer); } /* interrupts are disabled, so free the lock for schedule */ atmel_spi_unlock(as); dma_timeout = wait_for_completion_timeout(&as->xfer_completion, SPI_DMA_TIMEOUT); atmel_spi_lock(as); if (WARN_ON(dma_timeout == 0)) { dev_err(&spi->dev, "spi transfer timeout\n"); as->done_status = -EIO; } if (as->done_status) break; } if (as->done_status) { if (as->use_pdc) { dev_warn(master->dev.parent, "overrun (%u/%u remaining)\n", spi_readl(as, TCR), spi_readl(as, RCR)); /* * Clean up DMA registers and make sure the data * registers are empty. */ spi_writel(as, RNCR, 0); spi_writel(as, TNCR, 0); spi_writel(as, RCR, 0); spi_writel(as, TCR, 0); for (timeout = 1000; timeout; timeout--) if (spi_readl(as, SR) & SPI_BIT(TXEMPTY)) break; if (!timeout) dev_warn(master->dev.parent, "timeout waiting for TXEMPTY"); while (spi_readl(as, SR) & SPI_BIT(RDRF)) spi_readl(as, RDR); /* Clear any overrun happening while cleaning up */ spi_readl(as, SR); } else if (atmel_spi_use_dma(as, xfer)) { atmel_spi_stop_dma(master); } if (!msg->is_dma_mapped && as->use_pdc) atmel_spi_dma_unmap_xfer(master, xfer); return 0; } else { /* only update length if no error */ msg->actual_length += xfer->len; } if (!msg->is_dma_mapped && as->use_pdc) atmel_spi_dma_unmap_xfer(master, xfer); if (xfer->delay_usecs) udelay(xfer->delay_usecs); if (xfer->cs_change) { if (list_is_last(&xfer->transfer_list, &msg->transfers)) { as->keep_cs = true; } else { as->cs_active = !as->cs_active; if (as->cs_active) cs_activate(as, msg->spi); else cs_deactivate(as, msg->spi); } } return 0; } static int atmel_spi_transfer_one_message(struct spi_master *master, struct spi_message *msg) { struct atmel_spi *as; struct spi_transfer *xfer; struct spi_device *spi = msg->spi; int ret = 0; as = spi_master_get_devdata(master); dev_dbg(&spi->dev, "new message %p submitted for %s\n", msg, dev_name(&spi->dev)); atmel_spi_lock(as); cs_activate(as, spi); as->cs_active = true; as->keep_cs = false; msg->status = 0; msg->actual_length = 0; list_for_each_entry(xfer, &msg->transfers, transfer_list) { ret = atmel_spi_one_transfer(master, msg, xfer); if (ret) goto msg_done; } if (as->use_pdc) atmel_spi_disable_pdc_transfer(as); list_for_each_entry(xfer, &msg->transfers, transfer_list) { dev_dbg(&spi->dev, " xfer %p: len %u tx %p/%pad rx %p/%pad\n", xfer, xfer->len, xfer->tx_buf, &xfer->tx_dma, xfer->rx_buf, &xfer->rx_dma); } msg_done: if (!as->keep_cs) cs_deactivate(as, msg->spi); atmel_spi_unlock(as); msg->status = as->done_status; spi_finalize_current_message(spi->master); return ret; } static void atmel_spi_cleanup(struct spi_device *spi) { struct atmel_spi_device *asd = spi->controller_state; if (!asd) return; spi->controller_state = NULL; kfree(asd); } static inline unsigned int atmel_get_version(struct atmel_spi *as) { return spi_readl(as, VERSION) & 0x00000fff; } static void atmel_get_caps(struct atmel_spi *as) { unsigned int version; version = atmel_get_version(as); as->caps.is_spi2 = version > 0x121; as->caps.has_wdrbt = version >= 0x210; as->caps.has_dma_support = version >= 0x212; as->caps.has_pdc_support = version < 0x212; } /*-------------------------------------------------------------------------*/ static int atmel_spi_gpio_cs(struct platform_device *pdev) { struct spi_master *master = platform_get_drvdata(pdev); struct atmel_spi *as = spi_master_get_devdata(master); struct device_node *np = master->dev.of_node; int i; int ret = 0; int nb = 0; if (!as->use_cs_gpios) return 0; if (!np) return 0; nb = of_gpio_named_count(np, "cs-gpios"); for (i = 0; i < nb; i++) { int cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i); if (cs_gpio == -EPROBE_DEFER) return cs_gpio; if (gpio_is_valid(cs_gpio)) { ret = devm_gpio_request(&pdev->dev, cs_gpio, dev_name(&pdev->dev)); if (ret) return ret; } } return 0; } static void atmel_spi_init(struct atmel_spi *as) { spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ /* It is recommended to enable FIFOs first thing after reset */ if (as->fifo_size) spi_writel(as, CR, SPI_BIT(FIFOEN)); if (as->caps.has_wdrbt) { spi_writel(as, MR, SPI_BIT(WDRBT) | SPI_BIT(MODFDIS) | SPI_BIT(MSTR)); } else { spi_writel(as, MR, SPI_BIT(MSTR) | SPI_BIT(MODFDIS)); } if (as->use_pdc) spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); spi_writel(as, CR, SPI_BIT(SPIEN)); } static int atmel_spi_probe(struct platform_device *pdev) { struct resource *regs; int irq; struct clk *clk; int ret; struct spi_master *master; struct atmel_spi *as; /* Select default pin state */ pinctrl_pm_select_default_state(&pdev->dev); regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!regs) return -ENXIO; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; clk = devm_clk_get(&pdev->dev, "spi_clk"); if (IS_ERR(clk)) return PTR_ERR(clk); /* setup spi core then atmel-specific driver state */ ret = -ENOMEM; master = spi_alloc_master(&pdev->dev, sizeof(*as)); if (!master) goto out_free; /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16); master->dev.of_node = pdev->dev.of_node; master->bus_num = pdev->id; master->num_chipselect = master->dev.of_node ? 0 : 4; master->setup = atmel_spi_setup; master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX); master->transfer_one_message = atmel_spi_transfer_one_message; master->cleanup = atmel_spi_cleanup; master->auto_runtime_pm = true; master->max_dma_len = SPI_MAX_DMA_XFER; master->can_dma = atmel_spi_can_dma; platform_set_drvdata(pdev, master); as = spi_master_get_devdata(master); spin_lock_init(&as->lock); as->pdev = pdev; as->regs = devm_ioremap_resource(&pdev->dev, regs); if (IS_ERR(as->regs)) { ret = PTR_ERR(as->regs); goto out_unmap_regs; } as->phybase = regs->start; as->irq = irq; as->clk = clk; init_completion(&as->xfer_completion); atmel_get_caps(as); as->use_cs_gpios = true; if (atmel_spi_is_v2(as) && pdev->dev.of_node && !of_get_property(pdev->dev.of_node, "cs-gpios", NULL)) { as->use_cs_gpios = false; master->num_chipselect = 4; } ret = atmel_spi_gpio_cs(pdev); if (ret) goto out_unmap_regs; as->use_dma = false; as->use_pdc = false; if (as->caps.has_dma_support) { ret = atmel_spi_configure_dma(master, as); if (ret == 0) { as->use_dma = true; } else if (ret == -EPROBE_DEFER) { return ret; } } else if (as->caps.has_pdc_support) { as->use_pdc = true; } if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) { as->addr_rx_bbuf = dma_alloc_coherent(&pdev->dev, SPI_MAX_DMA_XFER, &as->dma_addr_rx_bbuf, GFP_KERNEL | GFP_DMA); if (!as->addr_rx_bbuf) { as->use_dma = false; } else { as->addr_tx_bbuf = dma_alloc_coherent(&pdev->dev, SPI_MAX_DMA_XFER, &as->dma_addr_tx_bbuf, GFP_KERNEL | GFP_DMA); if (!as->addr_tx_bbuf) { as->use_dma = false; dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER, as->addr_rx_bbuf, as->dma_addr_rx_bbuf); } } if (!as->use_dma) dev_info(master->dev.parent, " can not allocate dma coherent memory\n"); } if (as->caps.has_dma_support && !as->use_dma) dev_info(&pdev->dev, "Atmel SPI Controller using PIO only\n"); if (as->use_pdc) { ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pdc_interrupt, 0, dev_name(&pdev->dev), master); } else { ret = devm_request_irq(&pdev->dev, irq, atmel_spi_pio_interrupt, 0, dev_name(&pdev->dev), master); } if (ret) goto out_unmap_regs; /* Initialize the hardware */ ret = clk_prepare_enable(clk); if (ret) goto out_free_irq; as->spi_clk = clk_get_rate(clk); as->fifo_size = 0; if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size", &as->fifo_size)) { dev_info(&pdev->dev, "Using FIFO (%u data)\n", as->fifo_size); } atmel_spi_init(as); pm_runtime_set_autosuspend_delay(&pdev->dev, 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) goto out_free_dma; /* go! */ dev_info(&pdev->dev, "Atmel SPI Controller version 0x%x at 0x%08lx (irq %d)\n", atmel_get_version(as), (unsigned long)regs->start, irq); return 0; out_free_dma: pm_runtime_disable(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); if (as->use_dma) atmel_spi_release_dma(master); spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ clk_disable_unprepare(clk); out_free_irq: out_unmap_regs: out_free: spi_master_put(master); return ret; } static int atmel_spi_remove(struct platform_device *pdev) { struct spi_master *master = platform_get_drvdata(pdev); struct atmel_spi *as = spi_master_get_devdata(master); pm_runtime_get_sync(&pdev->dev); /* reset the hardware and block queue progress */ if (as->use_dma) { atmel_spi_stop_dma(master); atmel_spi_release_dma(master); if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) { dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER, as->addr_tx_bbuf, as->dma_addr_tx_bbuf); dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER, as->addr_rx_bbuf, as->dma_addr_rx_bbuf); } } spin_lock_irq(&as->lock); spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ spi_readl(as, SR); spin_unlock_irq(&as->lock); clk_disable_unprepare(as->clk); pm_runtime_put_noidle(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; } #ifdef CONFIG_PM static int atmel_spi_runtime_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct atmel_spi *as = spi_master_get_devdata(master); clk_disable_unprepare(as->clk); pinctrl_pm_select_sleep_state(dev); return 0; } static int atmel_spi_runtime_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct atmel_spi *as = spi_master_get_devdata(master); pinctrl_pm_select_default_state(dev); return clk_prepare_enable(as->clk); } #ifdef CONFIG_PM_SLEEP static int atmel_spi_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); int ret; /* Stop the queue running */ ret = spi_master_suspend(master); if (ret) return ret; if (!pm_runtime_suspended(dev)) atmel_spi_runtime_suspend(dev); return 0; } static int atmel_spi_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct atmel_spi *as = spi_master_get_devdata(master); int ret; ret = clk_prepare_enable(as->clk); if (ret) return ret; atmel_spi_init(as); clk_disable_unprepare(as->clk); if (!pm_runtime_suspended(dev)) { ret = atmel_spi_runtime_resume(dev); if (ret) return ret; } /* Start the queue running */ return spi_master_resume(master); } #endif static const struct dev_pm_ops atmel_spi_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(atmel_spi_suspend, atmel_spi_resume) SET_RUNTIME_PM_OPS(atmel_spi_runtime_suspend, atmel_spi_runtime_resume, NULL) }; #define ATMEL_SPI_PM_OPS (&atmel_spi_pm_ops) #else #define ATMEL_SPI_PM_OPS NULL #endif #if defined(CONFIG_OF) static const struct of_device_id atmel_spi_dt_ids[] = { { .compatible = "atmel,at91rm9200-spi" }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids); #endif static struct platform_driver atmel_spi_driver = { .driver = { .name = "atmel_spi", .pm = ATMEL_SPI_PM_OPS, .of_match_table = of_match_ptr(atmel_spi_dt_ids), }, .probe = atmel_spi_probe, .remove = atmel_spi_remove, }; module_platform_driver(atmel_spi_driver); MODULE_DESCRIPTION("Atmel AT32/AT91 SPI Controller driver"); MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:atmel_spi");
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