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Release 4.11 drivers/spi/spi-fsl-espi.c

Directory: drivers/spi
/*
 * Freescale eSPI controller driver.
 *
 * Copyright 2010 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/fsl_devices.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
#include <sysdev/fsl_soc.h>

/* eSPI Controller registers */

#define ESPI_SPMODE	0x00	
/* eSPI mode register */

#define ESPI_SPIE	0x04	
/* eSPI event register */

#define ESPI_SPIM	0x08	
/* eSPI mask register */

#define ESPI_SPCOM	0x0c	
/* eSPI command register */

#define ESPI_SPITF	0x10	
/* eSPI transmit FIFO access register*/

#define ESPI_SPIRF	0x14	
/* eSPI receive FIFO access register*/

#define ESPI_SPMODE0	0x20	
/* eSPI cs0 mode register */


#define ESPI_SPMODEx(x)	(ESPI_SPMODE0 + (x) * 4)

/* eSPI Controller mode register definitions */

#define SPMODE_ENABLE		BIT(31)

#define SPMODE_LOOP		BIT(30)

#define SPMODE_TXTHR(x)		((x) << 8)

#define SPMODE_RXTHR(x)		((x) << 0)

/* eSPI Controller CS mode register definitions */

#define CSMODE_CI_INACTIVEHIGH	BIT(31)

#define CSMODE_CP_BEGIN_EDGECLK	BIT(30)

#define CSMODE_REV		BIT(29)

#define CSMODE_DIV16		BIT(28)

#define CSMODE_PM(x)		((x) << 24)

#define CSMODE_POL_1		BIT(20)

#define CSMODE_LEN(x)		((x) << 16)

#define CSMODE_BEF(x)		((x) << 12)

#define CSMODE_AFT(x)		((x) << 8)

#define CSMODE_CG(x)		((x) << 3)


#define FSL_ESPI_FIFO_SIZE	32

#define FSL_ESPI_RXTHR		15

/* Default mode/csmode for eSPI controller */

#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(FSL_ESPI_RXTHR))

#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
                | CSMODE_AFT(0) | CSMODE_CG(1))

/* SPIE register values */

#define SPIE_RXCNT(reg)     ((reg >> 24) & 0x3F)

#define SPIE_TXCNT(reg)     ((reg >> 16) & 0x3F)

#define	SPIE_TXE		BIT(15)	
/* TX FIFO empty */

#define	SPIE_DON		BIT(14)	
/* TX done */

#define	SPIE_RXT		BIT(13)	
/* RX FIFO threshold */

#define	SPIE_RXF		BIT(12)	
/* RX FIFO full */

#define	SPIE_TXT		BIT(11)	
/* TX FIFO threshold*/

#define	SPIE_RNE		BIT(9)	
/* RX FIFO not empty */

#define	SPIE_TNF		BIT(8)	
/* TX FIFO not full */

/* SPIM register values */

#define	SPIM_TXE		BIT(15)	
/* TX FIFO empty */

#define	SPIM_DON		BIT(14)	
/* TX done */

#define	SPIM_RXT		BIT(13)	
/* RX FIFO threshold */

#define	SPIM_RXF		BIT(12)	
/* RX FIFO full */

#define	SPIM_TXT		BIT(11)	
/* TX FIFO threshold*/

#define	SPIM_RNE		BIT(9)	
/* RX FIFO not empty */

#define	SPIM_TNF		BIT(8)	
/* TX FIFO not full */

/* SPCOM register values */

#define SPCOM_CS(x)		((x) << 30)

#define SPCOM_DO		BIT(28) 
/* Dual output */

#define SPCOM_TO		BIT(27) 
/* TX only */

#define SPCOM_RXSKIP(x)		((x) << 16)

#define SPCOM_TRANLEN(x)	((x) << 0)


#define	SPCOM_TRANLEN_MAX	0x10000	
/* Max transaction length */


#define AUTOSUSPEND_TIMEOUT 2000


struct fsl_espi {
	
struct device *dev;
	
void __iomem *reg_base;

	
struct list_head *m_transfers;
	
struct spi_transfer *tx_t;
	
unsigned int tx_pos;
	
bool tx_done;
	
struct spi_transfer *rx_t;
	
unsigned int rx_pos;
	
bool rx_done;

	
bool swab;
	
unsigned int rxskip;

	
spinlock_t lock;

	
u32 spibrg;             /* SPIBRG input clock */

	
struct completion done;
};


struct fsl_espi_cs {
	
u32 hw_mode;
};


static inline u32 fsl_espi_read_reg(struct fsl_espi *espi, int offset) { return ioread32be(espi->reg_base + offset); }

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static inline u16 fsl_espi_read_reg16(struct fsl_espi *espi, int offset) { return ioread16be(espi->reg_base + offset); }

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static inline u8 fsl_espi_read_reg8(struct fsl_espi *espi, int offset) { return ioread8(espi->reg_base + offset); }

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static inline void fsl_espi_write_reg(struct fsl_espi *espi, int offset, u32 val) { iowrite32be(val, espi->reg_base + offset); }

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static inline void fsl_espi_write_reg16(struct fsl_espi *espi, int offset, u16 val) { iowrite16be(val, espi->reg_base + offset); }

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static inline void fsl_espi_write_reg8(struct fsl_espi *espi, int offset, u8 val) { iowrite8(val, espi->reg_base + offset); }

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static int fsl_espi_check_message(struct spi_message *m) { struct fsl_espi *espi = spi_master_get_devdata(m->spi->master); struct spi_transfer *t, *first; if (m->frame_length > SPCOM_TRANLEN_MAX) { dev_err(espi->dev, "message too long, size is %u bytes\n", m->frame_length); return -EMSGSIZE; } first = list_first_entry(&m->transfers, struct spi_transfer, transfer_list); list_for_each_entry(t, &m->transfers, transfer_list) { if (first->bits_per_word != t->bits_per_word || first->speed_hz != t->speed_hz) { dev_err(espi->dev, "bits_per_word/speed_hz should be the same for all transfers\n"); return -EINVAL; } } /* ESPI supports MSB-first transfers for word size 8 / 16 only */ if (!(m->spi->mode & SPI_LSB_FIRST) && first->bits_per_word != 8 && first->bits_per_word != 16) { dev_err(espi->dev, "MSB-first transfer not supported for wordsize %u\n", first->bits_per_word); return -EINVAL; } return 0; }

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static unsigned int fsl_espi_check_rxskip_mode(struct spi_message *m) { struct spi_transfer *t; unsigned int i = 0, rxskip = 0; /* * prerequisites for ESPI rxskip mode: * - message has two transfers * - first transfer is a write and second is a read * * In addition the current low-level transfer mechanism requires * that the rxskip bytes fit into the TX FIFO. Else the transfer * would hang because after the first FSL_ESPI_FIFO_SIZE bytes * the TX FIFO isn't re-filled. */ list_for_each_entry(t, &m->transfers, transfer_list) { if (i == 0) { if (!t->tx_buf || t->rx_buf || t->len > FSL_ESPI_FIFO_SIZE) return 0; rxskip = t->len; } else if (i == 1) { if (t->tx_buf || !t->rx_buf) return 0; } i++; } return i == 2 ? rxskip : 0; }

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static void fsl_espi_fill_tx_fifo(struct fsl_espi *espi, u32 events) { u32 tx_fifo_avail; unsigned int tx_left; const void *tx_buf; /* if events is zero transfer has not started and tx fifo is empty */ tx_fifo_avail = events ? SPIE_TXCNT(events) : FSL_ESPI_FIFO_SIZE; start: tx_left = espi->tx_t->len - espi->tx_pos; tx_buf = espi->tx_t->tx_buf; while (tx_fifo_avail >= min(4U, tx_left) && tx_left) { if (tx_left >= 4) { if (!tx_buf) fsl_espi_write_reg(espi, ESPI_SPITF, 0); else if (espi->swab) fsl_espi_write_reg(espi, ESPI_SPITF, swahb32p(tx_buf + espi->tx_pos)); else fsl_espi_write_reg(espi, ESPI_SPITF, *(u32 *)(tx_buf + espi->tx_pos)); espi->tx_pos += 4; tx_left -= 4; tx_fifo_avail -= 4; } else if (tx_left >= 2 && tx_buf && espi->swab) { fsl_espi_write_reg16(espi, ESPI_SPITF, swab16p(tx_buf + espi->tx_pos)); espi->tx_pos += 2; tx_left -= 2; tx_fifo_avail -= 2; } else { if (!tx_buf) fsl_espi_write_reg8(espi, ESPI_SPITF, 0); else fsl_espi_write_reg8(espi, ESPI_SPITF, *(u8 *)(tx_buf + espi->tx_pos)); espi->tx_pos += 1; tx_left -= 1; tx_fifo_avail -= 1; } } if (!tx_left) { /* Last transfer finished, in rxskip mode only one is needed */ if (list_is_last(&espi->tx_t->transfer_list, espi->m_transfers) || espi->rxskip) { espi->tx_done = true; return; } espi->tx_t = list_next_entry(espi->tx_t, transfer_list); espi->tx_pos = 0; /* continue with next transfer if tx fifo is not full */ if (tx_fifo_avail) goto start; } }

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static void fsl_espi_read_rx_fifo(struct fsl_espi *espi, u32 events) { u32 rx_fifo_avail = SPIE_RXCNT(events); unsigned int rx_left; void *rx_buf; start: rx_left = espi->rx_t->len - espi->rx_pos; rx_buf = espi->rx_t->rx_buf; while (rx_fifo_avail >= min(4U, rx_left) && rx_left) { if (rx_left >= 4) { u32 val = fsl_espi_read_reg(espi, ESPI_SPIRF); if (rx_buf && espi->swab) *(u32 *)(rx_buf + espi->rx_pos) = swahb32(val); else if (rx_buf) *(u32 *)(rx_buf + espi->rx_pos) = val; espi->rx_pos += 4; rx_left -= 4; rx_fifo_avail -= 4; } else if (rx_left >= 2 && rx_buf && espi->swab) { u16 val = fsl_espi_read_reg16(espi, ESPI_SPIRF); *(u16 *)(rx_buf + espi->rx_pos) = swab16(val); espi->rx_pos += 2; rx_left -= 2; rx_fifo_avail -= 2; } else { u8 val = fsl_espi_read_reg8(espi, ESPI_SPIRF); if (rx_buf) *(u8 *)(rx_buf + espi->rx_pos) = val; espi->rx_pos += 1; rx_left -= 1; rx_fifo_avail -= 1; } } if (!rx_left) { if (list_is_last(&espi->rx_t->transfer_list, espi->m_transfers)) { espi->rx_done = true; return; } espi->rx_t = list_next_entry(espi->rx_t, transfer_list); espi->rx_pos = 0; /* continue with next transfer if rx fifo is not empty */ if (rx_fifo_avail) goto start; } }

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static void fsl_espi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) { struct fsl_espi *espi = spi_master_get_devdata(spi->master); int bits_per_word = t ? t->bits_per_word : spi->bits_per_word; u32 pm, hz = t ? t->speed_hz : spi->max_speed_hz; struct fsl_espi_cs *cs = spi_get_ctldata(spi); u32 hw_mode_old = cs->hw_mode; /* mask out bits we are going to set */ cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF)); cs->hw_mode |= CSMODE_LEN(bits_per_word - 1); pm = DIV_ROUND_UP(espi->spibrg, hz * 4) - 1; if (pm > 15) { cs->hw_mode |= CSMODE_DIV16; pm = DIV_ROUND_UP(espi->spibrg, hz * 16 * 4) - 1; } cs->hw_mode |= CSMODE_PM(pm); /* don't write the mode register if the mode doesn't change */ if (cs->hw_mode != hw_mode_old) fsl_espi_write_reg(espi, ESPI_SPMODEx(spi->chip_select), cs->hw_mode); }

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static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) { struct fsl_espi *espi = spi_master_get_devdata(spi->master); unsigned int rx_len = t->len; u32 mask, spcom; int ret; reinit_completion(&espi->done); /* Set SPCOM[CS] and SPCOM[TRANLEN] field */ spcom = SPCOM_CS(spi->chip_select); spcom |= SPCOM_TRANLEN(t->len - 1); /* configure RXSKIP mode */ if (espi->rxskip) { spcom |= SPCOM_RXSKIP(espi->rxskip); rx_len = t->len - espi->rxskip; if (t->rx_nbits == SPI_NBITS_DUAL) spcom |= SPCOM_DO; } fsl_espi_write_reg(espi, ESPI_SPCOM, spcom); /* enable interrupts */ mask = SPIM_DON; if (rx_len > FSL_ESPI_FIFO_SIZE) mask |= SPIM_RXT; fsl_espi_write_reg(espi, ESPI_SPIM, mask); /* Prevent filling the fifo from getting interrupted */ spin_lock_irq(&espi->lock); fsl_espi_fill_tx_fifo(espi, 0); spin_unlock_irq(&espi->lock); /* Won't hang up forever, SPI bus sometimes got lost interrupts... */ ret = wait_for_completion_timeout(&espi->done, 2 * HZ); if (ret == 0) dev_err(espi->dev, "Transfer timed out!\n"); /* disable rx ints */ fsl_espi_write_reg(espi, ESPI_SPIM, 0); return ret == 0 ? -ETIMEDOUT : 0; }

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static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans) { struct fsl_espi *espi = spi_master_get_devdata(m->spi->master); struct spi_device *spi = m->spi; int ret; /* In case of LSB-first and bits_per_word > 8 byte-swap all words */ espi->swab = spi->mode & SPI_LSB_FIRST && trans->bits_per_word > 8; espi->m_transfers = &m->transfers; espi->tx_t = list_first_entry(&m->transfers, struct spi_transfer, transfer_list); espi->tx_pos = 0; espi->tx_done = false; espi->rx_t = list_first_entry(&m->transfers, struct spi_transfer, transfer_list); espi->rx_pos = 0; espi->rx_done = false; espi->rxskip = fsl_espi_check_rxskip_mode(m); if (trans->rx_nbits == SPI_NBITS_DUAL && !espi->rxskip) { dev_err(espi->dev, "Dual output mode requires RXSKIP mode!\n"); return -EINVAL; } /* In RXSKIP mode skip first transfer for reads */ if (espi->rxskip) espi->rx_t = list_next_entry(espi->rx_t, transfer_list); fsl_espi_setup_transfer(spi, trans); ret = fsl_espi_bufs(spi, trans); if (trans->delay_usecs) udelay(trans->delay_usecs); return ret; }

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static int fsl_espi_do_one_msg(struct spi_master *master, struct spi_message *m) { unsigned int delay_usecs = 0, rx_nbits = 0; struct spi_transfer *t, trans = {}; int ret; ret = fsl_espi_check_message(m); if (ret) goto out; list_for_each_entry(t, &m->transfers, transfer_list) { if (t->delay_usecs > delay_usecs) delay_usecs = t->delay_usecs; if (t->rx_nbits > rx_nbits) rx_nbits = t->rx_nbits; } t = list_first_entry(&m->transfers, struct spi_transfer, transfer_list); trans.len = m->frame_length; trans.speed_hz = t->speed_hz; trans.bits_per_word = t->bits_per_word; trans.delay_usecs = delay_usecs; trans.rx_nbits = rx_nbits; if (trans.len) ret = fsl_espi_trans(m, &trans); m->actual_length = ret ? 0 : trans.len; out: if (m->status == -EINPROGRESS) m->status = ret; spi_finalize_current_message(master); return ret; }

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static int fsl_espi_setup(struct spi_device *spi) { struct fsl_espi *espi; u32 loop_mode; struct fsl_espi_cs *cs = spi_get_ctldata(spi); if (!cs) { cs = kzalloc(sizeof(*cs), GFP_KERNEL); if (!cs) return -ENOMEM; spi_set_ctldata(spi, cs); } espi = spi_master_get_devdata(spi->master); pm_runtime_get_sync(espi->dev); cs->hw_mode = fsl_espi_read_reg(espi, ESPI_SPMODEx(spi->chip_select)); /* mask out bits we are going to set */ cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH | CSMODE_REV); if (spi->mode & SPI_CPHA) cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK; if (spi->mode & SPI_CPOL) cs->hw_mode |= CSMODE_CI_INACTIVEHIGH; if (!(spi->mode & SPI_LSB_FIRST)) cs->hw_mode |= CSMODE_REV; /* Handle the loop mode */ loop_mode = fsl_espi_read_reg(espi, ESPI_SPMODE); loop_mode &= ~SPMODE_LOOP; if (spi->mode & SPI_LOOP) loop_mode |= SPMODE_LOOP; fsl_espi_write_reg(espi, ESPI_SPMODE, loop_mode); fsl_espi_setup_transfer(spi, NULL); pm_runtime_mark_last_busy(espi->dev); pm_runtime_put_autosuspend(espi->dev); return 0; }

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static void fsl_espi_cleanup(struct spi_device *spi) { struct fsl_espi_cs *cs = spi_get_ctldata(spi); kfree(cs); spi_set_ctldata(spi, NULL); }

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static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events) { if (!espi->rx_done) fsl_espi_read_rx_fifo(espi, events); if (!espi->tx_done) fsl_espi_fill_tx_fifo(espi, events); if (!espi->tx_done || !espi->rx_done) return; /* we're done, but check for errors before returning */ events = fsl_espi_read_reg(espi, ESPI_SPIE); if (!(events & SPIE_DON)) dev_err(espi->dev, "Transfer done but SPIE_DON isn't set!\n"); if (SPIE_RXCNT(events) || SPIE_TXCNT(events) != FSL_ESPI_FIFO_SIZE) dev_err(espi->dev, "Transfer done but rx/tx fifo's aren't empty!\n"); complete(&espi->done); }

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static irqreturn_t fsl_espi_irq(s32 irq, void *context_data) { struct fsl_espi *espi = context_data; u32 events; spin_lock(&espi->lock); /* Get interrupt events(tx/rx) */ events = fsl_espi_read_reg(espi, ESPI_SPIE); if (!events) { spin_unlock(&espi->lock); return IRQ_NONE; } dev_vdbg(espi->dev, "%s: events %x\n", __func__, events); fsl_espi_cpu_irq(espi, events); /* Clear the events */ fsl_espi_write_reg(espi, ESPI_SPIE, events); spin_unlock(&espi->lock); return IRQ_HANDLED; }

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#ifdef CONFIG_PM
static int fsl_espi_runtime_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct fsl_espi *espi = spi_master_get_devdata(master); u32 regval; regval = fsl_espi_read_reg(espi, ESPI_SPMODE); regval &= ~SPMODE_ENABLE; fsl_espi_write_reg(espi, ESPI_SPMODE, regval); return 0; }

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static int fsl_espi_runtime_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); struct fsl_espi *espi = spi_master_get_devdata(master); u32 regval; regval = fsl_espi_read_reg(espi, ESPI_SPMODE); regval |= SPMODE_ENABLE; fsl_espi_write_reg(espi, ESPI_SPMODE, regval); return 0; }

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#endif
static size_t fsl_espi_max_message_size(struct spi_device *spi) { return SPCOM_TRANLEN_MAX; }

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static void fsl_espi_init_regs(struct device *dev, bool initial) { struct spi_master *master = dev_get_drvdata(dev); struct fsl_espi *espi = spi_master_get_devdata(master); struct device_node *nc; u32 csmode, cs, prop; int ret; /* SPI controller initializations */ fsl_espi_write_reg(espi, ESPI_SPMODE, 0); fsl_espi_write_reg(espi, ESPI_SPIM, 0); fsl_espi_write_reg(espi, ESPI_SPCOM, 0); fsl_espi_write_reg(espi, ESPI_SPIE, 0xffffffff); /* Init eSPI CS mode register */ for_each_available_child_of_node(master->dev.of_node, nc) { /* get chip select */ ret = of_property_read_u32(nc, "reg", &cs); if (ret || cs >= master->num_chipselect) continue; csmode = CSMODE_INIT_VAL; /* check if CSBEF is set in device tree */ ret = of_property_read_u32(nc, "fsl,csbef", &prop); if (!ret) { csmode &= ~(CSMODE_BEF(0xf)); csmode |= CSMODE_BEF(prop); } /* check if CSAFT is set in device tree */ ret = of_property_read_u32(nc, "fsl,csaft", &prop); if (!ret) { csmode &= ~(CSMODE_AFT(0xf)); csmode |= CSMODE_AFT(prop); } fsl_espi_write_reg(espi, ESPI_SPMODEx(cs), csmode); if (initial) dev_info(dev, "cs=%u, init_csmode=0x%x\n", cs, csmode); } /* Enable SPI interface */ fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE); }

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Heiner Kallweit236100.00%2100.00%
Total236100.00%2100.00%


static int fsl_espi_probe(struct device *dev, struct resource *mem, unsigned int irq, unsigned int num_cs) { struct spi_master *master; struct fsl_espi *espi; int ret; master = spi_alloc_master(dev, sizeof(struct fsl_espi)); if (!master) return -ENOMEM; dev_set_drvdata(dev, master); master->mode_bits = SPI_RX_DUAL | SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST | SPI_LOOP; master->dev.of_node = dev->of_node; master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16); master->setup = fsl_espi_setup; master->cleanup = fsl_espi_cleanup; master->transfer_one_message = fsl_espi_do_one_msg; master->auto_runtime_pm = true; master->max_message_size = fsl_espi_max_message_size; master->num_chipselect = num_cs; espi = spi_master_get_devdata(master); spin_lock_init(&espi->lock); espi->dev = dev; espi->spibrg = fsl_get_sys_freq(); if (espi->spibrg == -1) { dev_err(dev, "Can't get sys frequency!\n"); ret = -EINVAL; goto err_probe; } /* determined by clock divider fields DIV16/PM in register SPMODEx */ master->min_speed_hz = DIV_ROUND_UP(espi->spibrg, 4 * 16 * 16); master->max_speed_hz = DIV_ROUND_UP(espi->spibrg, 4); init_completion(&espi->done); espi->reg_base = devm_ioremap_resource(dev, mem); if (IS_ERR(espi->reg_base)) { ret = PTR_ERR(espi->reg_base); goto err_probe; } /* Register for SPI Interrupt */ ret = devm_request_irq(dev, irq, fsl_espi_irq, 0, "fsl_espi", espi); if (ret) goto err_probe; fsl_espi_init_regs(dev, true); pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT); pm_runtime_use_autosuspend(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); pm_runtime_get_sync(dev); ret = devm_spi_register_master(dev, master); if (ret < 0) goto err_pm; dev_info(dev, "at 0x%p (irq = %u)\n", espi->reg_base, irq); pm_runtime_mark_last_busy(dev); pm_runtime_put_autosuspend(dev); return 0; err_pm: pm_runtime_put_noidle(dev); pm_runtime_disable(dev); pm_runtime_set_suspended(dev); err_probe: spi_master_put(master); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Heiner Kallweit24261.11%1676.19%
Mingkai Hu11228.28%14.76%
Jane Wan215.30%14.76%
Stephen Warren112.78%14.76%
Axel Lin61.52%14.76%
Michal Suchanek41.01%14.76%
Total396100.00%21100.00%


static int of_fsl_espi_get_chipselects(struct device *dev) { struct device_node *np = dev->of_node; u32 num_cs; int ret; ret = of_property_read_u32(np, "fsl,espi-num-chipselects", &num_cs); if (ret) { dev_err(dev, "No 'fsl,espi-num-chipselects' property\n"); return 0; } return num_cs; }

Contributors

PersonTokensPropCommitsCommitProp
Mingkai Hu4985.96%133.33%
Heiner Kallweit814.04%266.67%
Total57100.00%3100.00%


static int of_fsl_espi_probe(struct platform_device *ofdev) { struct device *dev = &ofdev->dev; struct device_node *np = ofdev->dev.of_node; struct resource mem; unsigned int irq, num_cs; int ret; if (of_property_read_bool(np, "mode")) { dev_err(dev, "mode property is not supported on ESPI!\n"); return -EINVAL; } num_cs = of_fsl_espi_get_chipselects(dev); if (!num_cs) return -EINVAL; ret = of_address_to_resource(np, 0, &mem); if (ret) return ret; irq = irq_of_parse_and_map(np, 0); if (!irq) return -EINVAL; return fsl_espi_probe(dev, &mem, irq, num_cs); }

Contributors

PersonTokensPropCommitsCommitProp
Mingkai Hu8966.92%114.29%
Heiner Kallweit3929.32%457.14%
Thierry Reding43.01%114.29%
Hou Zhiqiang10.75%114.29%
Total133100.00%7100.00%


static int of_fsl_espi_remove(struct platform_device *dev) { pm_runtime_disable(&dev->dev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Heiner Kallweit22100.00%1100.00%
Total22100.00%1100.00%

#ifdef CONFIG_PM_SLEEP
static int of_fsl_espi_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); int ret; ret = spi_master_suspend(master); if (ret) { dev_warn(dev, "cannot suspend master\n"); return ret; } return pm_runtime_force_suspend(dev); }

Contributors

PersonTokensPropCommitsCommitProp
Hou Zhiqiang5094.34%133.33%
Heiner Kallweit35.66%266.67%
Total53100.00%3100.00%


static int of_fsl_espi_resume(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); int ret; fsl_espi_init_regs(dev, false); ret = pm_runtime_force_resume(dev); if (ret < 0) return ret; return spi_master_resume(master); }

Contributors

PersonTokensPropCommitsCommitProp
Hou Zhiqiang3362.26%133.33%
Heiner Kallweit2037.74%266.67%
Total53100.00%3100.00%

#endif /* CONFIG_PM_SLEEP */ static const struct dev_pm_ops espi_pm = { SET_RUNTIME_PM_OPS(fsl_espi_runtime_suspend, fsl_espi_runtime_resume, NULL) SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume) }; static const struct of_device_id of_fsl_espi_match[] = { { .compatible = "fsl,mpc8536-espi" }, {} }; MODULE_DEVICE_TABLE(of, of_fsl_espi_match); static struct platform_driver fsl_espi_driver = { .driver = { .name = "fsl_espi", .of_match_table = of_fsl_espi_match, .pm = &espi_pm, }, .probe = of_fsl_espi_probe, .remove = of_fsl_espi_remove, }; module_platform_driver(fsl_espi_driver); MODULE_AUTHOR("Mingkai Hu"); MODULE_DESCRIPTION("Enhanced Freescale SPI Driver"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Heiner Kallweit265567.85%5168.00%
Mingkai Hu97424.89%22.67%
Hou Zhiqiang1122.86%34.00%
Axel Lin491.25%22.67%
Nobuteru Hayashi240.61%34.00%
Jane Wan220.56%22.67%
Paulo Zaneti190.49%11.33%
Michal Suchanek170.43%11.33%
Stephen Warren120.31%22.67%
Sebastian Andrzej Siewior70.18%11.33%
Xiubo Li70.18%11.33%
Rob Herring60.15%11.33%
Thierry Reding40.10%11.33%
Grant C. Likely20.05%22.67%
Wolfram Sang20.05%11.33%
Jonatas Rech10.03%11.33%
Total3913100.00%75100.00%
Directory: drivers/spi
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