drivers/net/can/sja1000/sja1000_platform.c - linux - Git at Google

 /*
  * Copyright (C) 2005 Sascha Hauer, Pengutronix
  * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the version 2 of the GNU General Public License
  * as published by the Free Software Foundation
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/delay.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/irq.h>
 #include <linux/can/dev.h>
 #include <linux/can/platform/sja1000.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_irq.h>

 #include "sja1000.h"

 #define DRV_NAME "sja1000_platform"
 #define SP_CAN_CLOCK  (16000000 / 2)

 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
 MODULE_ALIAS("platform:" DRV_NAME);
 MODULE_LICENSE("GPL v2");

 struct sja1000_of_data {
 	size_t  priv_sz;
 	int     (*init)(struct sja1000_priv *priv, struct device_node *of);
 };

 struct technologic_priv {
 	spinlock_t      io_lock;
 };

 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
 {
 	return ioread8(priv->reg_base + reg);
 }

 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
 {
 	iowrite8(val, priv->reg_base + reg);
 }

 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
 {
 	return ioread8(priv->reg_base + reg * 2);
 }

 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
 {
 	iowrite8(val, priv->reg_base + reg * 2);
 }

 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
 {
 	return ioread8(priv->reg_base + reg * 4);
 }

 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
 {
 	iowrite8(val, priv->reg_base + reg * 4);
 }

 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg)
 {
 	struct technologic_priv *tp = priv->priv;
 	unsigned long flags;
 	u8 val;

 	spin_lock_irqsave(&tp->io_lock, flags);
 	iowrite16(reg, priv->reg_base + 0);
 	val = ioread16(priv->reg_base + 2);
 	spin_unlock_irqrestore(&tp->io_lock, flags);

 	return val;
 }

 static void sp_technologic_write_reg16(const struct sja1000_priv *priv,
 				       int reg, u8 val)
 {
 	struct technologic_priv *tp = priv->priv;
 	unsigned long flags;

 	spin_lock_irqsave(&tp->io_lock, flags);
 	iowrite16(reg, priv->reg_base + 0);
 	iowrite16(val, priv->reg_base + 2);
 	spin_unlock_irqrestore(&tp->io_lock, flags);
 }

 static int sp_technologic_init(struct sja1000_priv *priv, struct device_node *of)
 {
 	struct technologic_priv *tp = priv->priv;

 	priv->read_reg = sp_technologic_read_reg16;
 	priv->write_reg = sp_technologic_write_reg16;
 	spin_lock_init(&tp->io_lock);

 	return 0;
 }

 static void sp_populate(struct sja1000_priv *priv,
 			struct sja1000_platform_data *pdata,
 			unsigned long resource_mem_flags)
 {
 	/* The CAN clock frequency is half the oscillator clock frequency */
 	priv->can.clock.freq = pdata->osc_freq / 2;
 	priv->ocr = pdata->ocr;
 	priv->cdr = pdata->cdr;

 	switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
 	case IORESOURCE_MEM_32BIT:
 		priv->read_reg = sp_read_reg32;
 		priv->write_reg = sp_write_reg32;
 		break;
 	case IORESOURCE_MEM_16BIT:
 		priv->read_reg = sp_read_reg16;
 		priv->write_reg = sp_write_reg16;
 		break;
 	case IORESOURCE_MEM_8BIT:
 	default:
 		priv->read_reg = sp_read_reg8;
 		priv->write_reg = sp_write_reg8;
 		break;
 	}
 }

 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
 {
 	int err;
 	u32 prop;

 	err = of_property_read_u32(of, "reg-io-width", &prop);
 	if (err)
 		prop = 1; /* 8 bit is default */

 	switch (prop) {
 	case 4:
 		priv->read_reg = sp_read_reg32;
 		priv->write_reg = sp_write_reg32;
 		break;
 	case 2:
 		priv->read_reg = sp_read_reg16;
 		priv->write_reg = sp_write_reg16;
 		break;
 	case 1:	/* fallthrough */
 	default:
 		priv->read_reg = sp_read_reg8;
 		priv->write_reg = sp_write_reg8;
 	}

 	err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
 	if (!err)
 		priv->can.clock.freq = prop / 2;
 	else
 		priv->can.clock.freq = SP_CAN_CLOCK; /* default */

 	err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
 	if (!err)
 		priv->ocr |= prop & OCR_MODE_MASK;
 	else
 		priv->ocr |= OCR_MODE_NORMAL; /* default */

 	err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
 	if (!err)
 		priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
 	else
 		priv->ocr |= OCR_TX0_PULLDOWN; /* default */

 	err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
 	if (!err && prop) {
 		u32 divider = priv->can.clock.freq * 2 / prop;

 		if (divider > 1)
 			priv->cdr |= divider / 2 - 1;
 		else
 			priv->cdr |= CDR_CLKOUT_MASK;
 	} else {
 		priv->cdr |= CDR_CLK_OFF; /* default */
 	}

 	if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
 		priv->cdr |= CDR_CBP; /* default */
 }

 static struct sja1000_of_data technologic_data = {
 	.priv_sz = sizeof(struct technologic_priv),
 	.init = sp_technologic_init,
 };

 static const struct of_device_id sp_of_table[] = {
 	{ .compatible = "nxp,sja1000", .data = NULL, },
 	{ .compatible = "technologic,sja1000", .data = &technologic_data, },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, sp_of_table);

 static int sp_probe(struct platform_device *pdev)
 {
 	int err, irq = 0;
 	void __iomem *addr;
 	struct net_device *dev;
 	struct sja1000_priv *priv;
 	struct resource *res_mem, *res_irq = NULL;
 	struct sja1000_platform_data *pdata;
 	struct device_node *of = pdev->dev.of_node;
 	const struct of_device_id *of_id;
 	const struct sja1000_of_data *of_data = NULL;
 	size_t priv_sz = 0;

 	pdata = dev_get_platdata(&pdev->dev);
 	if (!pdata && !of) {
 		dev_err(&pdev->dev, "No platform data provided!\n");
 		return -ENODEV;
 	}

 	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res_mem)
 		return -ENODEV;

 	if (!devm_request_mem_region(&pdev->dev, res_mem->start,
 				     resource_size(res_mem), DRV_NAME))
 		return -EBUSY;

 	addr = devm_ioremap_nocache(&pdev->dev, res_mem->start,
 				    resource_size(res_mem));
 	if (!addr)
 		return -ENOMEM;

 	if (of)
 		irq = irq_of_parse_and_map(of, 0);
 	else
 		res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);

 	if (!irq && !res_irq)
 		return -ENODEV;

 	of_id = of_match_device(sp_of_table, &pdev->dev);
 	if (of_id && of_id->data) {
 		of_data = of_id->data;
 		priv_sz = of_data->priv_sz;
 	}

 	dev = alloc_sja1000dev(priv_sz);
 	if (!dev)
 		return -ENOMEM;
 	priv = netdev_priv(dev);

 	if (res_irq) {
 		irq = res_irq->start;
 		priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
 		if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
 			priv->irq_flags |= IRQF_SHARED;
 	} else {
 		priv->irq_flags = IRQF_SHARED;
 	}

 	dev->irq = irq;
 	priv->reg_base = addr;

 	if (of) {
 		sp_populate_of(priv, of);

 		if (of_data && of_data->init) {
 			err = of_data->init(priv, of);
 			if (err)
 				goto exit_free;
 		}
 	} else {
 		sp_populate(priv, pdata, res_mem->flags);
 	}

 	platform_set_drvdata(pdev, dev);
 	SET_NETDEV_DEV(dev, &pdev->dev);

 	err = register_sja1000dev(dev);
 	if (err) {
 		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
 			DRV_NAME, err);
 		goto exit_free;
 	}

 	dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
 		 DRV_NAME, priv->reg_base, dev->irq);
 	return 0;

  exit_free:
 	free_sja1000dev(dev);
 	return err;
 }

 static int sp_remove(struct platform_device *pdev)
 {
 	struct net_device *dev = platform_get_drvdata(pdev);

 	unregister_sja1000dev(dev);
 	free_sja1000dev(dev);

 	return 0;
 }

 static struct platform_driver sp_driver = {
 	.probe = sp_probe,
 	.remove = sp_remove,
 	.driver = {
 		.name = DRV_NAME,
 		.of_match_table = sp_of_table,
 	},
 };

 module_platform_driver(sp_driver);
	/*
	* Copyright (C) 2005 Sascha Hauer, Pengutronix
	* Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the version 2 of the GNU General Public License
	* as published by the Free Software Foundation
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <linux/netdevice.h>
	#include <linux/delay.h>
	#include <linux/pci.h>
	#include <linux/platform_device.h>
	#include <linux/irq.h>
	#include <linux/can/dev.h>
	#include <linux/can/platform/sja1000.h>
	#include <linux/io.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/of_irq.h>

	#include "sja1000.h"

	#define DRV_NAME "sja1000_platform"
	#define SP_CAN_CLOCK (16000000 / 2)

	MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
	MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
	MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
	MODULE_ALIAS("platform:" DRV_NAME);
	MODULE_LICENSE("GPL v2");

	struct sja1000_of_data {
	size_t priv_sz;
	int (init)(struct sja1000_priv priv, struct device_node *of);
	};

	struct technologic_priv {
	spinlock_t io_lock;
	};

	static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
	{
	return ioread8(priv->reg_base + reg);
	}

	static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
	{
	iowrite8(val, priv->reg_base + reg);
	}

	static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
	{
	return ioread8(priv->reg_base + reg * 2);
	}

	static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
	{
	iowrite8(val, priv->reg_base + reg * 2);
	}

	static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
	{
	return ioread8(priv->reg_base + reg * 4);
	}

	static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
	{
	iowrite8(val, priv->reg_base + reg * 4);
	}

	static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg)
	{
	struct technologic_priv *tp = priv->priv;
	unsigned long flags;
	u8 val;

	spin_lock_irqsave(&tp->io_lock, flags);
	iowrite16(reg, priv->reg_base + 0);
	val = ioread16(priv->reg_base + 2);
	spin_unlock_irqrestore(&tp->io_lock, flags);

	return val;
	}

	static void sp_technologic_write_reg16(const struct sja1000_priv *priv,
	int reg, u8 val)
	{
	struct technologic_priv *tp = priv->priv;
	unsigned long flags;

	spin_lock_irqsave(&tp->io_lock, flags);
	iowrite16(reg, priv->reg_base + 0);
	iowrite16(val, priv->reg_base + 2);
	spin_unlock_irqrestore(&tp->io_lock, flags);
	}

	static int sp_technologic_init(struct sja1000_priv priv, struct device_node of)
	{
	struct technologic_priv *tp = priv->priv;

	priv->read_reg = sp_technologic_read_reg16;
	priv->write_reg = sp_technologic_write_reg16;
	spin_lock_init(&tp->io_lock);

	return 0;
	}

	static void sp_populate(struct sja1000_priv *priv,
	struct sja1000_platform_data *pdata,
	unsigned long resource_mem_flags)
	{
	/* The CAN clock frequency is half the oscillator clock frequency */
	priv->can.clock.freq = pdata->osc_freq / 2;
	priv->ocr = pdata->ocr;
	priv->cdr = pdata->cdr;

	switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
	case IORESOURCE_MEM_32BIT:
	priv->read_reg = sp_read_reg32;
	priv->write_reg = sp_write_reg32;
	break;
	case IORESOURCE_MEM_16BIT:
	priv->read_reg = sp_read_reg16;
	priv->write_reg = sp_write_reg16;
	break;
	case IORESOURCE_MEM_8BIT:
	default:
	priv->read_reg = sp_read_reg8;
	priv->write_reg = sp_write_reg8;
	break;
	}
	}

	static void sp_populate_of(struct sja1000_priv priv, struct device_node of)
	{
	int err;
	u32 prop;

	err = of_property_read_u32(of, "reg-io-width", &prop);
	if (err)
	prop = 1; /* 8 bit is default */

	switch (prop) {
	case 4:
	priv->read_reg = sp_read_reg32;
	priv->write_reg = sp_write_reg32;
	break;
	case 2:
	priv->read_reg = sp_read_reg16;
	priv->write_reg = sp_write_reg16;
	break;
	case 1: /* fallthrough */
	default:
	priv->read_reg = sp_read_reg8;
	priv->write_reg = sp_write_reg8;
	}

	err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
	if (!err)
	priv->can.clock.freq = prop / 2;
	else
	priv->can.clock.freq = SP_CAN_CLOCK; /* default */

	err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
	if (!err)
	priv->ocr \|= prop & OCR_MODE_MASK;
	else
	priv->ocr \|= OCR_MODE_NORMAL; /* default */

	err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
	if (!err)
	priv->ocr \|= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
	else
	priv->ocr \|= OCR_TX0_PULLDOWN; /* default */

	err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
	if (!err && prop) {
	u32 divider = priv->can.clock.freq * 2 / prop;

	if (divider > 1)
	priv->cdr \|= divider / 2 - 1;
	else
	priv->cdr \|= CDR_CLKOUT_MASK;
	} else {
	priv->cdr \|= CDR_CLK_OFF; /* default */
	}

	if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
	priv->cdr \|= CDR_CBP; /* default */
	}

	static struct sja1000_of_data technologic_data = {
	.priv_sz = sizeof(struct technologic_priv),
	.init = sp_technologic_init,
	};

	static const struct of_device_id sp_of_table[] = {
	{ .compatible = "nxp,sja1000", .data = NULL, },
	{ .compatible = "technologic,sja1000", .data = &technologic_data, },
	{ /* sentinel */ },
	};
	MODULE_DEVICE_TABLE(of, sp_of_table);

	static int sp_probe(struct platform_device *pdev)
	{
	int err, irq = 0;
	void __iomem *addr;
	struct net_device *dev;
	struct sja1000_priv *priv;
	struct resource res_mem, res_irq = NULL;
	struct sja1000_platform_data *pdata;
	struct device_node *of = pdev->dev.of_node;
	const struct of_device_id *of_id;
	const struct sja1000_of_data *of_data = NULL;
	size_t priv_sz = 0;

	pdata = dev_get_platdata(&pdev->dev);
	if (!pdata && !of) {
	dev_err(&pdev->dev, "No platform data provided!\n");
	return -ENODEV;
	}

	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res_mem)
	return -ENODEV;

	if (!devm_request_mem_region(&pdev->dev, res_mem->start,
	resource_size(res_mem), DRV_NAME))
	return -EBUSY;

	addr = devm_ioremap_nocache(&pdev->dev, res_mem->start,
	resource_size(res_mem));
	if (!addr)
	return -ENOMEM;

	if (of)
	irq = irq_of_parse_and_map(of, 0);
	else
	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);

	if (!irq && !res_irq)
	return -ENODEV;

	of_id = of_match_device(sp_of_table, &pdev->dev);
	if (of_id && of_id->data) {
	of_data = of_id->data;
	priv_sz = of_data->priv_sz;
	}

	dev = alloc_sja1000dev(priv_sz);
	if (!dev)
	return -ENOMEM;
	priv = netdev_priv(dev);

	if (res_irq) {
	irq = res_irq->start;
	priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
	if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
	priv->irq_flags \|= IRQF_SHARED;
	} else {
	priv->irq_flags = IRQF_SHARED;
	}

	dev->irq = irq;
	priv->reg_base = addr;

	if (of) {
	sp_populate_of(priv, of);

	if (of_data && of_data->init) {
	err = of_data->init(priv, of);
	if (err)
	goto exit_free;
	}
	} else {
	sp_populate(priv, pdata, res_mem->flags);
	}

	platform_set_drvdata(pdev, dev);
	SET_NETDEV_DEV(dev, &pdev->dev);

	err = register_sja1000dev(dev);
	if (err) {
	dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
	DRV_NAME, err);
	goto exit_free;
	}

	dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
	DRV_NAME, priv->reg_base, dev->irq);
	return 0;

	exit_free:
	free_sja1000dev(dev);
	return err;
	}

	static int sp_remove(struct platform_device *pdev)
	{
	struct net_device *dev = platform_get_drvdata(pdev);

	unregister_sja1000dev(dev);
	free_sja1000dev(dev);

	return 0;
	}

	static struct platform_driver sp_driver = {
	.probe = sp_probe,
	.remove = sp_remove,
	.driver = {
	.name = DRV_NAME,
	.of_match_table = sp_of_table,
	},
	};

	module_platform_driver(sp_driver);