diff options
| -rw-r--r-- | Documentation/devicetree/bindings/spi/spi-octeon.txt | 33 | ||||
| -rw-r--r-- | drivers/spi/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/spi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/spi/spi-octeon.c | 362 | 
4 files changed, 403 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-octeon.txt b/Documentation/devicetree/bindings/spi/spi-octeon.txt new file mode 100644 index 00000000000..431add19234 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-octeon.txt @@ -0,0 +1,33 @@ +Cavium, Inc. OCTEON SOC SPI master controller. + +Required properties: +- compatible : "cavium,octeon-3010-spi" +- reg : The register base for the controller. +- interrupts : One interrupt, used by the controller. +- #address-cells : <1>, as required by generic SPI binding. +- #size-cells : <0>, also as required by generic SPI binding. + +Child nodes as per the generic SPI binding. + +Example: + +	spi@1070000001000 { +		compatible = "cavium,octeon-3010-spi"; +		reg = <0x10700 0x00001000 0x0 0x100>; +		interrupts = <0 58>; +		#address-cells = <1>; +		#size-cells = <0>; + +		eeprom@0 { +			compatible = "st,m95256", "atmel,at25"; +			reg = <0>; +			spi-max-frequency = <5000000>; +			spi-cpha; +			spi-cpol; + +			pagesize = <64>; +			size = <32768>; +			address-width = <16>; +		}; +	}; + diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 5f84b5563c2..d654f88f4cf 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -237,6 +237,13 @@ config SPI_OC_TINY  	help  	  This is the driver for OpenCores tiny SPI master controller. +config SPI_OCTEON +	tristate "Cavium OCTEON SPI controller" +	depends on CPU_CAVIUM_OCTEON +	help +	  SPI host driver for the hardware found on some Cavium OCTEON +	  SOCs. +  config SPI_OMAP_UWIRE  	tristate "OMAP1 MicroWire"  	depends on ARCH_OMAP1 diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 3920dcf4c74..93d87bcdf3f 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_SPI_MPC52xx_PSC)		+= spi-mpc52xx-psc.o  obj-$(CONFIG_SPI_MPC52xx)		+= spi-mpc52xx.o  obj-$(CONFIG_SPI_NUC900)		+= spi-nuc900.o  obj-$(CONFIG_SPI_OC_TINY)		+= spi-oc-tiny.o +obj-$(CONFIG_SPI_OCTEON)		+= spi-octeon.o  obj-$(CONFIG_SPI_OMAP_UWIRE)		+= spi-omap-uwire.o  obj-$(CONFIG_SPI_OMAP_100K)		+= spi-omap-100k.o  obj-$(CONFIG_SPI_OMAP24XX)		+= spi-omap2-mcspi.o diff --git a/drivers/spi/spi-octeon.c b/drivers/spi/spi-octeon.c new file mode 100644 index 00000000000..ea8fb2efb0f --- /dev/null +++ b/drivers/spi/spi-octeon.c @@ -0,0 +1,362 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License.  See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2011, 2012 Cavium, Inc. + */ + +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/spi/spi.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/of.h> + +#include <asm/octeon/octeon.h> +#include <asm/octeon/cvmx-mpi-defs.h> + +#define OCTEON_SPI_CFG 0 +#define OCTEON_SPI_STS 0x08 +#define OCTEON_SPI_TX 0x10 +#define OCTEON_SPI_DAT0 0x80 + +#define OCTEON_SPI_MAX_BYTES 9 + +#define OCTEON_SPI_MAX_CLOCK_HZ 16000000 + +struct octeon_spi { +	struct spi_master *my_master; +	u64 register_base; +	u64 last_cfg; +	u64 cs_enax; +}; + +struct octeon_spi_setup { +	u32 max_speed_hz; +	u8 chip_select; +	u8 mode; +	u8 bits_per_word; +}; + +static void octeon_spi_wait_ready(struct octeon_spi *p) +{ +	union cvmx_mpi_sts mpi_sts; +	unsigned int loops = 0; + +	do { +		if (loops++) +			__delay(500); +		mpi_sts.u64 = cvmx_read_csr(p->register_base + OCTEON_SPI_STS); +	} while (mpi_sts.s.busy); +} + +static int octeon_spi_do_transfer(struct octeon_spi *p, +				  struct spi_message *msg, +				  struct spi_transfer *xfer, +				  bool last_xfer) +{ +	union cvmx_mpi_cfg mpi_cfg; +	union cvmx_mpi_tx mpi_tx; +	unsigned int clkdiv; +	unsigned int speed_hz; +	int mode; +	bool cpha, cpol; +	int bits_per_word; +	const u8 *tx_buf; +	u8 *rx_buf; +	int len; +	int i; + +	struct octeon_spi_setup *msg_setup = spi_get_ctldata(msg->spi); + +	speed_hz = msg_setup->max_speed_hz; +	mode = msg_setup->mode; +	cpha = mode & SPI_CPHA; +	cpol = mode & SPI_CPOL; +	bits_per_word = msg_setup->bits_per_word; + +	if (xfer->speed_hz) +		speed_hz = xfer->speed_hz; +	if (xfer->bits_per_word) +		bits_per_word = xfer->bits_per_word; + +	if (speed_hz > OCTEON_SPI_MAX_CLOCK_HZ) +		speed_hz = OCTEON_SPI_MAX_CLOCK_HZ; + +	clkdiv = octeon_get_io_clock_rate() / (2 * speed_hz); + +	mpi_cfg.u64 = 0; + +	mpi_cfg.s.clkdiv = clkdiv; +	mpi_cfg.s.cshi = (mode & SPI_CS_HIGH) ? 1 : 0; +	mpi_cfg.s.lsbfirst = (mode & SPI_LSB_FIRST) ? 1 : 0; +	mpi_cfg.s.wireor = (mode & SPI_3WIRE) ? 1 : 0; +	mpi_cfg.s.idlelo = cpha != cpol; +	mpi_cfg.s.cslate = cpha ? 1 : 0; +	mpi_cfg.s.enable = 1; + +	if (msg_setup->chip_select < 4) +		p->cs_enax |= 1ull << (12 + msg_setup->chip_select); +	mpi_cfg.u64 |= p->cs_enax; + +	if (mpi_cfg.u64 != p->last_cfg) { +		p->last_cfg = mpi_cfg.u64; +		cvmx_write_csr(p->register_base + OCTEON_SPI_CFG, mpi_cfg.u64); +	} +	tx_buf = xfer->tx_buf; +	rx_buf = xfer->rx_buf; +	len = xfer->len; +	while (len > OCTEON_SPI_MAX_BYTES) { +		for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) { +			u8 d; +			if (tx_buf) +				d = *tx_buf++; +			else +				d = 0; +			cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d); +		} +		mpi_tx.u64 = 0; +		mpi_tx.s.csid = msg_setup->chip_select; +		mpi_tx.s.leavecs = 1; +		mpi_tx.s.txnum = tx_buf ? OCTEON_SPI_MAX_BYTES : 0; +		mpi_tx.s.totnum = OCTEON_SPI_MAX_BYTES; +		cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64); + +		octeon_spi_wait_ready(p); +		if (rx_buf) +			for (i = 0; i < OCTEON_SPI_MAX_BYTES; i++) { +				u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i)); +				*rx_buf++ = (u8)v; +			} +		len -= OCTEON_SPI_MAX_BYTES; +	} + +	for (i = 0; i < len; i++) { +		u8 d; +		if (tx_buf) +			d = *tx_buf++; +		else +			d = 0; +		cvmx_write_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i), d); +	} + +	mpi_tx.u64 = 0; +	mpi_tx.s.csid = msg_setup->chip_select; +	if (last_xfer) +		mpi_tx.s.leavecs = xfer->cs_change; +	else +		mpi_tx.s.leavecs = !xfer->cs_change; +	mpi_tx.s.txnum = tx_buf ? len : 0; +	mpi_tx.s.totnum = len; +	cvmx_write_csr(p->register_base + OCTEON_SPI_TX, mpi_tx.u64); + +	octeon_spi_wait_ready(p); +	if (rx_buf) +		for (i = 0; i < len; i++) { +			u64 v = cvmx_read_csr(p->register_base + OCTEON_SPI_DAT0 + (8 * i)); +			*rx_buf++ = (u8)v; +		} + +	if (xfer->delay_usecs) +		udelay(xfer->delay_usecs); + +	return xfer->len; +} + +static int octeon_spi_validate_bpw(struct spi_device *spi, u32 speed) +{ +	switch (speed) { +	case 8: +		break; +	default: +		dev_err(&spi->dev, "Error: %d bits per word not supported\n", +			speed); +		return -EINVAL; +	} +	return 0; +} + +static int octeon_spi_transfer_one_message(struct spi_master *master, +					   struct spi_message *msg) +{ +	struct octeon_spi *p = spi_master_get_devdata(master); +	unsigned int total_len = 0; +	int status = 0; +	struct spi_transfer *xfer; + +	/* +	 * We better have set the configuration via a call to .setup +	 * before we get here. +	 */ +	if (spi_get_ctldata(msg->spi) == NULL) { +		status = -EINVAL; +		goto err; +	} + +	list_for_each_entry(xfer, &msg->transfers, transfer_list) { +		if (xfer->bits_per_word) { +			status = octeon_spi_validate_bpw(msg->spi, +							 xfer->bits_per_word); +			if (status) +				goto err; +		} +	} + +	list_for_each_entry(xfer, &msg->transfers, transfer_list) { +		bool last_xfer = &xfer->transfer_list == msg->transfers.prev; +		int r = octeon_spi_do_transfer(p, msg, xfer, last_xfer); +		if (r < 0) { +			status = r; +			goto err; +		} +		total_len += r; +	} +err: +	msg->status = status; +	msg->actual_length = total_len; +	spi_finalize_current_message(master); +	return status; +} + +static struct octeon_spi_setup *octeon_spi_new_setup(struct spi_device *spi) +{ +	struct octeon_spi_setup *setup = kzalloc(sizeof(*setup), GFP_KERNEL); +	if (!setup) +		return NULL; + +	setup->max_speed_hz = spi->max_speed_hz; +	setup->chip_select = spi->chip_select; +	setup->mode = spi->mode; +	setup->bits_per_word = spi->bits_per_word; +	return setup; +} + +static int octeon_spi_setup(struct spi_device *spi) +{ +	int r; +	struct octeon_spi_setup *new_setup; +	struct octeon_spi_setup *old_setup = spi_get_ctldata(spi); + +	r = octeon_spi_validate_bpw(spi, spi->bits_per_word); +	if (r) +		return r; + +	new_setup = octeon_spi_new_setup(spi); +	if (!new_setup) +		return -ENOMEM; + +	spi_set_ctldata(spi, new_setup); +	kfree(old_setup); + +	return 0; +} + +static void octeon_spi_cleanup(struct spi_device *spi) +{ +	struct octeon_spi_setup *old_setup = spi_get_ctldata(spi); +	spi_set_ctldata(spi, NULL); +	kfree(old_setup); +} + +static int octeon_spi_nop_transfer_hardware(struct spi_master *master) +{ +	return 0; +} + +static int __devinit octeon_spi_probe(struct platform_device *pdev) +{ + +	struct resource *res_mem; +	struct spi_master *master; +	struct octeon_spi *p; +	int err = -ENOENT; + +	master = spi_alloc_master(&pdev->dev, sizeof(struct octeon_spi)); +	if (!master) +		return -ENOMEM; +	p = spi_master_get_devdata(master); +	platform_set_drvdata(pdev, p); +	p->my_master = master; + +	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + +	if (res_mem == NULL) { +		dev_err(&pdev->dev, "found no memory resource\n"); +		err = -ENXIO; +		goto fail; +	} +	if (!devm_request_mem_region(&pdev->dev, res_mem->start, +				     resource_size(res_mem), res_mem->name)) { +		dev_err(&pdev->dev, "request_mem_region failed\n"); +		goto fail; +	} +	p->register_base = (u64)devm_ioremap(&pdev->dev, res_mem->start, +					     resource_size(res_mem)); + +	/* Dynamic bus numbering */ +	master->bus_num = -1; +	master->num_chipselect = 4; +	master->mode_bits = SPI_CPHA | +			    SPI_CPOL | +			    SPI_CS_HIGH | +			    SPI_LSB_FIRST | +			    SPI_3WIRE; + +	master->setup = octeon_spi_setup; +	master->cleanup = octeon_spi_cleanup; +	master->prepare_transfer_hardware = octeon_spi_nop_transfer_hardware; +	master->transfer_one_message = octeon_spi_transfer_one_message; +	master->unprepare_transfer_hardware = octeon_spi_nop_transfer_hardware; + +	master->dev.of_node = pdev->dev.of_node; +	err = spi_register_master(master); +	if (err) { +		dev_err(&pdev->dev, "register master failed: %d\n", err); +		goto fail; +	} + +	dev_info(&pdev->dev, "OCTEON SPI bus driver\n"); + +	return 0; +fail: +	spi_master_put(master); +	return err; +} + +static int __devexit octeon_spi_remove(struct platform_device *pdev) +{ +	struct octeon_spi *p = platform_get_drvdata(pdev); +	u64 register_base = p->register_base; + +	spi_unregister_master(p->my_master); + +	/* Clear the CSENA* and put everything in a known state. */ +	cvmx_write_csr(register_base + OCTEON_SPI_CFG, 0); + +	return 0; +} + +static struct of_device_id octeon_spi_match[] = { +	{ .compatible = "cavium,octeon-3010-spi", }, +	{}, +}; +MODULE_DEVICE_TABLE(of, octeon_spi_match); + +static struct platform_driver octeon_spi_driver = { +	.driver = { +		.name		= "spi-octeon", +		.owner		= THIS_MODULE, +		.of_match_table = octeon_spi_match, +	}, +	.probe		= octeon_spi_probe, +	.remove		= __devexit_p(octeon_spi_remove), +}; + +module_platform_driver(octeon_spi_driver); + +MODULE_DESCRIPTION("Cavium, Inc. OCTEON SPI bus driver"); +MODULE_AUTHOR("David Daney"); +MODULE_LICENSE("GPL");  |