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Release 4.7 drivers/spi/spi-atmel.c

Directory: drivers/spi
/*
 * 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/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_dma {
	
struct dma_chan			*chan_rx;
	
struct dma_chan			*chan_tx;
	
struct scatterlist		sgrx;
	
struct scatterlist		sgtx;
	
struct dma_async_tx_descriptor	*data_desc_rx;
	
struct dma_async_tx_descriptor	*data_desc_tx;

	
struct at_dma_slave	dma_slave;
};


struct atmel_spi_caps {
	
bool	is_spi2;
	
bool	has_wdrbt;
	
bool	has_dma_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;

	
struct spi_transfer	*current_transfer;
	
int			current_remaining_bytes;
	
int			done_status;

	
struct completion	xfer_completion;

	/* scratch buffer */
	
void			*buffer;
	
dma_addr_t		buffer_dma;

	
struct atmel_spi_caps	caps;

	
bool			use_dma;
	
bool			use_pdc;
	
bool			use_cs_gpios;
	/* dmaengine data */
	
struct atmel_spi_dma	dma;

	
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 BUFFER_SIZE		PAGE_SIZE

#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; }

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/* * 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); }

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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); }

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static void atmel_spi_lock(struct atmel_spi *as) __acquires(&as->lock

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) { spin_lock_irqsave(&as->lock, as->flags); }
static void atmel_spi_unlock(struct atmel_spi *as) __releases(&as->lock

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) { spin_unlock_irqrestore(&as->lock, as->flags); }
static inline bool atmel_spi_use_dma(struct atmel_spi *as, struct spi_transfer *xfer) { return as->use_dma && xfer->len >= DMA_MIN_BYTES; }

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static int atmel_spi_dma_slave_config(struct atmel_spi *as, struct dma_slave_config *slave_config, u8 bits_per_word) { 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(as->dma.chan_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(as->dma.chan_rx, slave_config)) { dev_err(&as->pdev->dev, "failed to configure rx dma channel\n"); err = -EINVAL; } return err; }

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static int atmel_spi_configure_dma(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); as->dma.chan_tx = dma_request_slave_channel_reason(dev, "tx"); if (IS_ERR(as->dma.chan_tx)) { err = PTR_ERR(as->dma.chan_tx); if (err == -EPROBE_DEFER) { dev_warn(dev, "no DMA channel available at the moment\n"); return err; } dev_err(dev, "DMA TX channel not available, SPI unable to use DMA\n"); err = -EBUSY; goto error; } /* * No reason to check EPROBE_DEFER here since we have already requested * tx channel. If it fails here, it's for another reason. */ as->dma.chan_rx = dma_request_slave_channel(dev, "rx"); if (!as->dma.chan_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(as->dma.chan_tx), dma_chan_name(as->dma.chan_rx)); return 0; error: if (as->dma.chan_rx) dma_release_channel(as->dma.chan_rx); if (!IS_ERR(as->dma.chan_tx)) dma_release_channel(as->dma.chan_tx); return err; }

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static void atmel_spi_stop_dma(struct atmel_spi *as) { if (as->dma.chan_rx) dmaengine_terminate_all(as->dma.chan_rx); if (as->dma.chan_tx) dmaengine_terminate_all(as->dma.chan_tx); }

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static void atmel_spi_release_dma(struct atmel_spi *as) { if (as->dma.chan_rx) dma_release_channel(as->dma.chan_rx); if (as->dma.chan_tx) dma_release_channel(as->dma.chan_tx); }

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/* 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); complete(&as->xfer_completion); }

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/* * 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->tx_buf) { 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)); } else { spi_writel(as, TDR, 0); } 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)); }

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Total199100.00%7100.00%

/* * 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->tx_buf) { if (xfer->bits_per_word > 8) { td0 = *words++; td1 = *words++; } else { td0 = *bytes++; td1 = *bytes++; } } else { td0 = 0; td1 = 0; } spi_writel(as, TDR, (td1 << 16) | td0); num_data -= 2; } if (num_data) { if (xfer->tx_buf) { if (xfer->bits_per_word > 8) td0 = *words++; else td0 = *bytes++; } else { td0 = 0; } 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)); }

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cyrille pitchencyrille pitchen33984.96%112.50%
haavard skinnemoenhaavard skinnemoen276.77%225.00%
nicolas ferrenicolas ferre133.26%112.50%
gerard kamgerard kam92.26%112.50%
richard genoudrichard genoud61.50%112.50%
wenyou yangwenyou yang30.75%112.50%
silvester erdegsilvester erdeg20.50%112.50%
Total399100.00%8100.00%

/* * 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); }

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cyrille pitchencyrille pitchen47100.00%1100.00%
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/* * 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 = as->dma.chan_rx; struct dma_chan *txchan = as->dma.chan_tx; struct dma_async_tx_descriptor *rxdesc; struct dma_async_tx_descriptor *txdesc; struct dma_slave_config slave_config; dma_cookie_t cookie; u32 len = *plen; 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); /* prepare the RX dma transfer */ sg_init_table(&as->dma.sgrx, 1); if (xfer->rx_buf) { as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen; } else { as->dma.sgrx.dma_address = as->buffer_dma; if (len > BUFFER_SIZE) len = BUFFER_SIZE; } /* prepare the TX dma transfer */ sg_init_table(&as->dma.sgtx, 1); if (xfer->tx_buf) { as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen; } else { as->dma.sgtx.dma_address = as->buffer_dma; if (len > BUFFER_SIZE) len = BUFFER_SIZE; memset(as->buffer, 0, len); } sg_dma_len(&as->dma.sgtx) = len; sg_dma_len(&as->dma.sgrx) = len; *plen = len; if (atmel_spi_dma_slave_config(as, &slave_config, xfer->bits_per_word)) goto err_exit; /* Send both scatterlists */ rxdesc = dmaengine_prep_slave_sg(rxchan, &as->dma.sgrx, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!rxdesc) goto err_dma; txdesc = dmaengine_prep_slave_sg(txchan, &as->dma.sgtx, 1, DMA_TO_DEVICE, 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(as); err_exit: atmel_spi_lock(as); return -ENOMEM; }

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nicolas ferrenicolas ferre48293.05%114.29%
emil goodeemil goode112.12%114.29%
haavard skinnemoenhaavard skinnemoen112.12%114.29%
gerard kamgerard kam50.97%114.29%
silvester erdegsilvester erdeg40.77%114.29%
david mosbergerdavid mosberger30.58%114.29%
geert uytterhoevengeert uytterhoeven20.39%114.29%
Total518100.00%7100.00%


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) { struct atmel_spi *as = spi_master_get_devdata(master); u32 len = *plen; /* use scratch buffer only when rx or tx data is unspecified */ if (xfer->rx_buf) *rx_dma = xfer->rx_dma + xfer->len - *plen; else { *rx_dma = as->buffer_dma; if (len > BUFFER_SIZE) len = BUFFER_SIZE; } if (xfer->tx_buf) *tx_dma = xfer->tx_dma + xfer->len - *plen; else { *tx_dma = as->buffer_dma; if (len > BUFFER_SIZE) len = BUFFER_SIZE; memset(as->buffer, 0, len); dma_sync_single_for_device(&as->pdev->dev, as->buffer_dma, len, DMA_TO_DEVICE); } *plen = len; }

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nicolas ferrenicolas ferre159100.00%1100.00%
Total159100.00%1100.00%


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 = clk_get_rate(as->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; }

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richard genoudrichard genoud175100.00%1100.00%
Total175100.00%1100.00%

/* * 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)); }

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nicolas ferrenicolas ferre27981.34%125.00%
wenyou yangwenyou yang4011.66%125.00%
emil goodeemil goode226.41%125.00%
torsten fleischertorsten fleischer20.58%125.00%
Total343100.00%4100.00%

/* * 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; }

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wenyou yangwenyou yang9660.38%133.33%
nicolas ferrenicolas ferre6037.74%133.33%
richard genoudrichard genoud31.89%133.33%
Total159100.00%3100.00%


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); }

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nicolas ferrenicolas ferre3347.14%150.00%
Total70100.00%2100.00%


static void atmel_spi_disable_pdc_transfer(struct atmel_spi *as) { spi_writel(as, PTCR, SPI_BIT(RXTDIS) | SPI_BIT(TXTDIS)); }

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nicolas ferrenicolas ferre1035.71%150.00%
Total28100.00%2100.00%


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->rx_buf) { 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); } } else { 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--; } }

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cyrille pitchencyrille pitchen15898.75%133.33%
nicolas ferrenicolas ferre10.62%133.33%
wenyou yangwenyou yang10.62%133.33%
Total160100.00%3100.00%


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->rx_buf) { if (xfer->bits_per_word > 8) *words++ = rd; else *bytes++ = rd; } num_data--; } }

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cyrille pitchencyrille pitchen12462.31%125.00%
wenyou yangwenyou yang3517.59%125.00%
nicolas ferrenicolas ferre3417.09%125.00%
alexandre bellonialexandre belloni63.02%125.00%
Total199100.00%4100.00%

/* 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); }

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cyrille pitchencyrille pitchen3286.49%133.33%
wenyou yangwenyou yang410.81%133.33%
nicolas ferrenicolas ferre12.70%133.33%
Total37100.00%3100.00%

/* 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; }

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nicolas ferrenicolas ferre5321.90%116.67%
haavard skinnemoenhaavard skinnemoen218.68%116.67%
cyrille pitchencyrille pitchen72.89%116.67%
david brownelldavid brownell52.07%116.67%
kay sieverskay sievers20.83%116.67%
Total242100.00%6100.00%


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; }

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nicolas ferrenicolas ferre3017.54%133.33%
richard genoudrichard genoud2916.96%133.33%
Total171100.00%3100.00%


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; int ret; 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) { ret = gpio_request(npcs_pin, dev_name(&spi->dev)); if (ret) { kfree(asd); return ret; } 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; }

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wenyou yangwenyou yang20457.30%114.29%
haavard skinnemoenhaavard skinnemoen6618.54%114.29%
cyrille pitchencyrille pitchen4813.48%114.29%
nicolas ferrenicolas ferre246.74%114.29%
david brownelldavid brownell123.37%114.29%
mark brownmark brown10.28%114.29%
fujita tomonorifujita tomonori10.28%114.29%
Total356100.00%7100.00%


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) && (atmel_spi_use_dma(as, xfer) || 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(as); } if (!msg->is_dma_mapped && (atmel_spi_use_dma(as, xfer) || 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 && (atmel_spi_use_dma(as, xfer) || 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; }

Contributors

PersonTokensPropCommitsCommitProp
wenyou yangwenyou yang47266.76%212.50%
haavard skinnemoenhaavard skinnemoen15021.22%318.75%
david brownelldavid brownell385.37%212.50%
axel linaxel lin141.98%16.25%
alexander steinalexander stein111.56%16.25%
nicholas mc guirenicholas mc guire70.99%16.25%
jean-christophe plagniol-villardjean-christophe plagniol-villard50.71%16.25%
nicolas ferrenicolas ferre40.57%212.50%
silvester erdegsilvester erdeg20.28%16.25%
gerard kamgerard kam20.28%16.25%
kay sieverskay sievers20.28%16.25%
Total707100.00%16100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen11651.10%114.29%
wenyou yangwenyou yang8838.77%114.29%
matthias bruggermatthias brugger73.08%114.29%
nicolas ferrenicolas ferre73.08%114.29%
kay sieverskay sievers41.76%114.29%
randy dunlaprandy dunlap31.32%114.29%
richard genoudrichard genoud20.88%114.29%
Total227100.00%7100.00%


static void atmel_spi_cleanup(struct spi_device *spi) { struct atmel_spi_device *asd = spi->controller_state; unsigned gpio = (unsigned long) spi->controller_data; if (!asd) return; spi->controller_state = NULL; gpio_free(gpio); kfree(asd); }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen3667.92%250.00%
david brownelldavid brownell1630.19%125.00%
mark brownmark brown11.89%125.00%
Total53100.00%4100.00%


static inline unsigned int atmel_get_version(struct atmel_spi *as) { return spi_readl(as, VERSION) & 0x00000fff; }

Contributors

PersonTokensPropCommitsCommitProp
wenyou yangwenyou yang23100.00%1100.00%
Total23100.00%1100.00%


static void atmel_get_caps(struct atmel_spi *as) { unsigned int version; version = atmel_get_version(as); dev_info(&as->pdev->dev, "version: 0x%x\n", version); as->caps.is_spi2 = version > 0x121; as->caps.has_wdrbt = version >= 0x210; as->caps.has_dma_support = version >= 0x212; }

Contributors

PersonTokensPropCommitsCommitProp
wenyou yangwenyou yang66100.00%1100.00%
Total66100.00%1100.00%

/*-------------------------------------------------------------------------*/
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->transfer_one_message = atmel_spi_transfer_one_message; master->cleanup = atmel_spi_cleanup; master->auto_runtime_pm = true; platform_set_drvdata(pdev, master); as = spi_master_get_devdata(master); /* * Scratch buffer is used for throwaway rx and tx data. * It's coherent to minimize dcache pollution. */ as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE, &as->buffer_dma, GFP_KERNEL); if (!as->buffer) goto out_free; 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_free_buffer; } 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; } as->use_dma = false; as->use_pdc = false; if (as->caps.has_dma_support) { ret = atmel_spi_configure_dma(as); if (ret == 0) as->use_dma = true; else if (ret == -EPROBE_DEFER) return ret; } else { as->use_pdc = true; } 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; spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ 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)); 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); spi_writel(as, CR, SPI_BIT(FIFOEN)); } /* go! */ dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n", (unsigned long)regs->start, irq); 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; return 0; out_free_dma: pm_runtime_disable(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); if (as->use_dma) atmel_spi_release_dma(as); 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_buffer: dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, as->buffer_dma); out_free: spi_master_put(master); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen41546.11%14.17%
nicolas ferrenicolas ferre12614.00%28.33%
wenyou yangwenyou yang11512.78%416.67%
cyrille pitchencyrille pitchen10011.11%312.50%
jean-christophe lallemandjean-christophe lallemand262.89%14.17%
jean-christophe plagniol-villardjean-christophe plagniol-villard202.22%14.17%
jingoo hanjingoo han192.11%14.17%
ludovic desrochesludovic desroches171.89%14.17%
wei yongjunwei yongjun141.56%14.17%
david brownelldavid brownell121.33%28.33%
stephen warrenstephen warren111.22%14.17%
boris brezillonboris brezillon101.11%14.17%
sachin kamatsachin kamat60.67%28.33%
kay sieverskay sievers40.44%14.17%
mark brownmark brown40.44%14.17%
h hartley sweetenh hartley sweeten10.11%14.17%
Total900100.00%24100.00%


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 */ spin_lock_irq(&as->lock); if (as->use_dma) { atmel_spi_stop_dma(as); atmel_spi_release_dma(as); } 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); dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer, as->buffer_dma); clk_disable_unprepare(as->clk); pm_runtime_put_noidle(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen9462.67%120.00%
wenyou yangwenyou yang2416.00%120.00%
nicolas ferrenicolas ferre1812.00%120.00%
jean-christophe lallemandjean-christophe lallemand138.67%120.00%
boris brezillonboris brezillon10.67%120.00%
Total150100.00%5100.00%

#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; }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen3576.09%120.00%
wenyou yangwenyou yang613.04%240.00%
jingoo hanjingoo han48.70%120.00%
boris brezillonboris brezillon12.17%120.00%
Total46100.00%5100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
haavard skinnemoenhaavard skinnemoen3272.73%120.00%
wenyou yangwenyou yang715.91%240.00%
jingoo hanjingoo han49.09%120.00%
boris brezillonboris brezillon12.27%120.00%
Total44100.00%5100.00%

#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) { dev_warn(dev, "cannot suspend master\n"); return ret; } if (!pm_runtime_suspended(dev)) atmel_spi_runtime_suspend(dev); return 0; }

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PersonTokensPropCommitsCommitProp
wenyou yangwenyou yang6398.44%266.67%
jingoo hanjingoo han11.56%133.33%
Total64100.00%3100.00%


static int atmel_spi_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); int ret; if (!pm_runtime_suspended(dev)) { ret = atmel_spi_runtime_resume(dev); if (ret) return ret; } /* Start the queue running */ ret = spi_master_resume(master); if (ret) dev_err(dev, "problem starting queue (%d)\n", ret); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
wenyou yangwenyou yang7097.22%250.00%
fengguang wufengguang wu11.39%125.00%
jingoo hanjingoo han11.39%125.00%
Total72100.00%4100.00%

#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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nicolas ferrenicolas ferre186923.46%46.15%
wenyou yangwenyou yang182422.89%69.23%
haavard skinnemoenhaavard skinnemoen139617.52%57.69%
cyrille pitchencyrille pitchen125115.70%34.62%
grant likelygrant likely5216.54%23.08%
richard genoudrichard genoud2663.34%34.62%
david brownelldavid brownell2022.54%46.15%
silvester erdegsilvester erdeg1141.43%11.54%
atsushi nemotoatsushi nemoto831.04%11.54%
jean-christophe plagniol-villardjean-christophe plagniol-villard750.94%23.08%
ludovic desrochesludovic desroches570.72%23.08%
jingoo hanjingoo han430.54%23.08%
jean-christophe lallemandjean-christophe lallemand390.49%11.54%
emil goodeemil goode330.41%11.54%
ben dooksben dooks270.34%11.54%
gerard kamgerard kam210.26%11.54%
kay sieverskay sievers170.21%23.08%
axel linaxel lin150.19%11.54%
wei yongjunwei yongjun140.18%11.54%
mark brownmark brown140.18%34.62%
boris brezillonboris brezillon130.16%11.54%
alexander steinalexander stein110.14%11.54%
alexandre bellonialexandre belloni110.14%23.08%
stephen warrenstephen warren110.14%11.54%
nicholas mc guirenicholas mc guire70.09%11.54%
sachin kamatsachin kamat70.09%23.08%
matthias bruggermatthias brugger70.09%11.54%
david mosbergerdavid mosberger30.04%11.54%
tejun heotejun heo30.04%11.54%
randy dunlaprandy dunlap30.04%11.54%
geert uytterhoevengeert uytterhoeven20.03%11.54%
vinod koulvinod koul20.03%11.54%
torsten fleischertorsten fleischer20.03%11.54%
fengguang wufengguang wu10.01%11.54%
fujita tomonorifujita tomonori10.01%11.54%
jean delvarejean delvare10.01%11.54%
h hartley sweetenh hartley sweeten10.01%11.54%
Total7967100.00%65100.00%
Directory: drivers/spi
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