drivers/net/can/cc770/cc770_platform.c - maze/linux - Git at Google

 /*
  * Driver for CC770 and AN82527 CAN controllers on the platform bus
  *
  * Copyright (C) 2009, 2011 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.
  */

 /*
  * If platform data are used you should have similar definitions
  * in your board-specific code:
  *
  *   static struct cc770_platform_data myboard_cc770_pdata = {
  *           .osc_freq = 16000000,
  *           .cir = 0x41,
  *           .cor = 0x20,
  *           .bcr = 0x40,
  *   };
  *
  * Please see include/linux/can/platform/cc770.h for description of
  * above fields.
  *
  * If the device tree is used, you need a CAN node definition in your
  * DTS file similar to:
  *
  *   can@3,100 {
  *           compatible = "bosch,cc770";
  *           reg = <3 0x100 0x80>;
  *           interrupts = <2 0>;
  *           interrupt-parent = <&mpic>;
  *           bosch,external-clock-frequency = <16000000>;
  *   };
  *
  * See "Documentation/devicetree/bindings/net/can/cc770.txt" for further
  * information.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/netdevice.h>
 #include <linux/delay.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/platform/cc770.h>

 #include "cc770.h"

 #define DRV_NAME "cc770_platform"

 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the platform bus");
 MODULE_LICENSE("GPL v2");
 MODULE_ALIAS("platform:" DRV_NAME);

 #define CC770_PLATFORM_CAN_CLOCK  16000000

 static u8 cc770_platform_read_reg(const struct cc770_priv *priv, int reg)
 {
 	return ioread8(priv->reg_base + reg);
 }

 static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg,
 				     u8 val)
 {
 	iowrite8(val, priv->reg_base + reg);
 }

 static int cc770_get_of_node_data(struct platform_device *pdev,
 				  struct cc770_priv *priv)
 {
 	struct device_node *np = pdev->dev.of_node;
 	const u32 *prop;
 	int prop_size;
 	u32 clkext;

 	prop = of_get_property(np, "bosch,external-clock-frequency",
 			       &prop_size);
 	if (prop && (prop_size ==  sizeof(u32)))
 		clkext = *prop;
 	else
 		clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
 	priv->can.clock.freq = clkext;

 	/* The system clock may not exceed 10 MHz */
 	if (priv->can.clock.freq > 10000000) {
 		priv->cpu_interface |= CPUIF_DSC;
 		priv->can.clock.freq /= 2;
 	}

 	/* The memory clock may not exceed 8 MHz */
 	if (priv->can.clock.freq > 8000000)
 		priv->cpu_interface |= CPUIF_DMC;

 	if (of_get_property(np, "bosch,divide-memory-clock", NULL))
 		priv->cpu_interface |= CPUIF_DMC;
 	if (of_get_property(np, "bosch,iso-low-speed-mux", NULL))
 		priv->cpu_interface |= CPUIF_MUX;

 	if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
 		priv->bus_config |= BUSCFG_CBY;
 	if (of_get_property(np, "bosch,disconnect-rx0-input", NULL))
 		priv->bus_config |= BUSCFG_DR0;
 	if (of_get_property(np, "bosch,disconnect-rx1-input", NULL))
 		priv->bus_config |= BUSCFG_DR1;
 	if (of_get_property(np, "bosch,disconnect-tx1-output", NULL))
 		priv->bus_config |= BUSCFG_DT1;
 	if (of_get_property(np, "bosch,polarity-dominant", NULL))
 		priv->bus_config |= BUSCFG_POL;

 	prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
 	if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
 		u32 cdv = clkext / *prop;
 		int slew;

 		if (cdv > 0 && cdv < 16) {
 			priv->cpu_interface |= CPUIF_CEN;
 			priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;

 			prop = of_get_property(np, "bosch,slew-rate",
 					       &prop_size);
 			if (prop && (prop_size == sizeof(u32))) {
 				slew = *prop;
 			} else {
 				/* Determine default slew rate */
 				slew = (CLKOUT_SL_MASK >>
 					CLKOUT_SL_SHIFT) -
 					((cdv * clkext - 1) / 8000000);
 				if (slew < 0)
 					slew = 0;
 			}
 			priv->clkout |= (slew << CLKOUT_SL_SHIFT) &
 				CLKOUT_SL_MASK;
 		} else {
 			dev_dbg(&pdev->dev, "invalid clock-out-frequency\n");
 		}
 	}

 	return 0;
 }

 static int cc770_get_platform_data(struct platform_device *pdev,
 				   struct cc770_priv *priv)
 {

 	struct cc770_platform_data *pdata = dev_get_platdata(&pdev->dev);

 	priv->can.clock.freq = pdata->osc_freq;
 	if (priv->cpu_interface & CPUIF_DSC)
 		priv->can.clock.freq /= 2;
 	priv->clkout = pdata->cor;
 	priv->bus_config = pdata->bcr;
 	priv->cpu_interface = pdata->cir;

 	return 0;
 }

 static int cc770_platform_probe(struct platform_device *pdev)
 {
 	struct net_device *dev;
 	struct cc770_priv *priv;
 	struct resource *mem;
 	resource_size_t mem_size;
 	void __iomem *base;
 	int err, irq;

 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_irq(pdev, 0);
 	if (!mem || irq <= 0)
 		return -ENODEV;

 	mem_size = resource_size(mem);
 	if (!request_mem_region(mem->start, mem_size, pdev->name))
 		return -EBUSY;

 	base = ioremap(mem->start, mem_size);
 	if (!base) {
 		err = -ENOMEM;
 		goto exit_release_mem;
 	}

 	dev = alloc_cc770dev(0);
 	if (!dev) {
 		err = -ENOMEM;
 		goto exit_unmap_mem;
 	}

 	dev->irq = irq;
 	priv = netdev_priv(dev);
 	priv->read_reg = cc770_platform_read_reg;
 	priv->write_reg = cc770_platform_write_reg;
 	priv->irq_flags = IRQF_SHARED;
 	priv->reg_base = base;

 	if (pdev->dev.of_node)
 		err = cc770_get_of_node_data(pdev, priv);
 	else if (dev_get_platdata(&pdev->dev))
 		err = cc770_get_platform_data(pdev, priv);
 	else
 		err = -ENODEV;
 	if (err)
 		goto exit_free_cc770;

 	dev_dbg(&pdev->dev,
 		 "reg_base=0x%p irq=%d clock=%d cpu_interface=0x%02x "
 		 "bus_config=0x%02x clkout=0x%02x\n",
 		 priv->reg_base, dev->irq, priv->can.clock.freq,
 		 priv->cpu_interface, priv->bus_config, priv->clkout);

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

 	err = register_cc770dev(dev);
 	if (err) {
 		dev_err(&pdev->dev,
 			"couldn't register CC700 device (err=%d)\n", err);
 		goto exit_free_cc770;
 	}

 	return 0;

 exit_free_cc770:
 	free_cc770dev(dev);
 exit_unmap_mem:
 	iounmap(base);
 exit_release_mem:
 	release_mem_region(mem->start, mem_size);

 	return err;
 }

 static int cc770_platform_remove(struct platform_device *pdev)
 {
 	struct net_device *dev = platform_get_drvdata(pdev);
 	struct cc770_priv *priv = netdev_priv(dev);
 	struct resource *mem;

 	unregister_cc770dev(dev);
 	iounmap(priv->reg_base);
 	free_cc770dev(dev);

 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	release_mem_region(mem->start, resource_size(mem));

 	return 0;
 }

 static struct of_device_id cc770_platform_table[] = {
 	{.compatible = "bosch,cc770"}, /* CC770 from Bosch */
 	{.compatible = "intc,82527"},  /* AN82527 from Intel CP */
 	{},
 };
 MODULE_DEVICE_TABLE(of, cc770_platform_table);

 static struct platform_driver cc770_platform_driver = {
 	.driver = {
 		.name = DRV_NAME,
 		.owner = THIS_MODULE,
 		.of_match_table = cc770_platform_table,
 	},
 	.probe = cc770_platform_probe,
 	.remove = cc770_platform_remove,
 };

 module_platform_driver(cc770_platform_driver);
	/*
	* Driver for CC770 and AN82527 CAN controllers on the platform bus
	*
	* Copyright (C) 2009, 2011 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.
	*/

	/*
	* If platform data are used you should have similar definitions
	* in your board-specific code:
	*
	* static struct cc770_platform_data myboard_cc770_pdata = {
	* .osc_freq = 16000000,
	* .cir = 0x41,
	* .cor = 0x20,
	* .bcr = 0x40,
	* };
	*
	* Please see include/linux/can/platform/cc770.h for description of
	* above fields.
	*
	* If the device tree is used, you need a CAN node definition in your
	* DTS file similar to:
	*
	* can@3,100 {
	* compatible = "bosch,cc770";
	* reg = <3 0x100 0x80>;
	* interrupts = <2 0>;
	* interrupt-parent = <&mpic>;
	* bosch,external-clock-frequency = <16000000>;
	* };
	*
	* See "Documentation/devicetree/bindings/net/can/cc770.txt" for further
	* information.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <linux/netdevice.h>
	#include <linux/delay.h>
	#include <linux/platform_device.h>
	#include <linux/of.h>
	#include <linux/can.h>
	#include <linux/can/dev.h>
	#include <linux/can/platform/cc770.h>

	#include "cc770.h"

	#define DRV_NAME "cc770_platform"

	MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
	MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the platform bus");
	MODULE_LICENSE("GPL v2");
	MODULE_ALIAS("platform:" DRV_NAME);

	#define CC770_PLATFORM_CAN_CLOCK 16000000

	static u8 cc770_platform_read_reg(const struct cc770_priv *priv, int reg)
	{
	return ioread8(priv->reg_base + reg);
	}

	static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg,
	u8 val)
	{
	iowrite8(val, priv->reg_base + reg);
	}

	static int cc770_get_of_node_data(struct platform_device *pdev,
	struct cc770_priv *priv)
	{
	struct device_node *np = pdev->dev.of_node;
	const u32 *prop;
	int prop_size;
	u32 clkext;

	prop = of_get_property(np, "bosch,external-clock-frequency",
	&prop_size);
	if (prop && (prop_size == sizeof(u32)))
	clkext = *prop;
	else
	clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
	priv->can.clock.freq = clkext;

	/* The system clock may not exceed 10 MHz */
	if (priv->can.clock.freq > 10000000) {
	priv->cpu_interface \|= CPUIF_DSC;
	priv->can.clock.freq /= 2;
	}

	/* The memory clock may not exceed 8 MHz */
	if (priv->can.clock.freq > 8000000)
	priv->cpu_interface \|= CPUIF_DMC;

	if (of_get_property(np, "bosch,divide-memory-clock", NULL))
	priv->cpu_interface \|= CPUIF_DMC;
	if (of_get_property(np, "bosch,iso-low-speed-mux", NULL))
	priv->cpu_interface \|= CPUIF_MUX;

	if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
	priv->bus_config \|= BUSCFG_CBY;
	if (of_get_property(np, "bosch,disconnect-rx0-input", NULL))
	priv->bus_config \|= BUSCFG_DR0;
	if (of_get_property(np, "bosch,disconnect-rx1-input", NULL))
	priv->bus_config \|= BUSCFG_DR1;
	if (of_get_property(np, "bosch,disconnect-tx1-output", NULL))
	priv->bus_config \|= BUSCFG_DT1;
	if (of_get_property(np, "bosch,polarity-dominant", NULL))
	priv->bus_config \|= BUSCFG_POL;

	prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
	if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
	u32 cdv = clkext / *prop;
	int slew;

	if (cdv > 0 && cdv < 16) {
	priv->cpu_interface \|= CPUIF_CEN;
	priv->clkout \|= (cdv - 1) & CLKOUT_CD_MASK;

	prop = of_get_property(np, "bosch,slew-rate",
	&prop_size);
	if (prop && (prop_size == sizeof(u32))) {
	slew = *prop;
	} else {
	/* Determine default slew rate */
	slew = (CLKOUT_SL_MASK >>
	CLKOUT_SL_SHIFT) -
	((cdv * clkext - 1) / 8000000);
	if (slew < 0)
	slew = 0;
	}
	priv->clkout \|= (slew << CLKOUT_SL_SHIFT) &
	CLKOUT_SL_MASK;
	} else {
	dev_dbg(&pdev->dev, "invalid clock-out-frequency\n");
	}
	}

	return 0;
	}

	static int cc770_get_platform_data(struct platform_device *pdev,
	struct cc770_priv *priv)
	{

	struct cc770_platform_data *pdata = dev_get_platdata(&pdev->dev);

	priv->can.clock.freq = pdata->osc_freq;
	if (priv->cpu_interface & CPUIF_DSC)
	priv->can.clock.freq /= 2;
	priv->clkout = pdata->cor;
	priv->bus_config = pdata->bcr;
	priv->cpu_interface = pdata->cir;

	return 0;
	}

	static int cc770_platform_probe(struct platform_device *pdev)
	{
	struct net_device *dev;
	struct cc770_priv *priv;
	struct resource *mem;
	resource_size_t mem_size;
	void __iomem *base;
	int err, irq;

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
	if (!mem \|\| irq <= 0)
	return -ENODEV;

	mem_size = resource_size(mem);
	if (!request_mem_region(mem->start, mem_size, pdev->name))
	return -EBUSY;

	base = ioremap(mem->start, mem_size);
	if (!base) {
	err = -ENOMEM;
	goto exit_release_mem;
	}

	dev = alloc_cc770dev(0);
	if (!dev) {
	err = -ENOMEM;
	goto exit_unmap_mem;
	}

	dev->irq = irq;
	priv = netdev_priv(dev);
	priv->read_reg = cc770_platform_read_reg;
	priv->write_reg = cc770_platform_write_reg;
	priv->irq_flags = IRQF_SHARED;
	priv->reg_base = base;

	if (pdev->dev.of_node)
	err = cc770_get_of_node_data(pdev, priv);
	else if (dev_get_platdata(&pdev->dev))
	err = cc770_get_platform_data(pdev, priv);
	else
	err = -ENODEV;
	if (err)
	goto exit_free_cc770;

	dev_dbg(&pdev->dev,
	"reg_base=0x%p irq=%d clock=%d cpu_interface=0x%02x "
	"bus_config=0x%02x clkout=0x%02x\n",
	priv->reg_base, dev->irq, priv->can.clock.freq,
	priv->cpu_interface, priv->bus_config, priv->clkout);

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

	err = register_cc770dev(dev);
	if (err) {
	dev_err(&pdev->dev,
	"couldn't register CC700 device (err=%d)\n", err);
	goto exit_free_cc770;
	}

	return 0;

	exit_free_cc770:
	free_cc770dev(dev);
	exit_unmap_mem:
	iounmap(base);
	exit_release_mem:
	release_mem_region(mem->start, mem_size);

	return err;
	}

	static int cc770_platform_remove(struct platform_device *pdev)
	{
	struct net_device *dev = platform_get_drvdata(pdev);
	struct cc770_priv *priv = netdev_priv(dev);
	struct resource *mem;

	unregister_cc770dev(dev);
	iounmap(priv->reg_base);
	free_cc770dev(dev);

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(mem->start, resource_size(mem));

	return 0;
	}

	static struct of_device_id cc770_platform_table[] = {
	{.compatible = "bosch,cc770"}, /* CC770 from Bosch */
	{.compatible = "intc,82527"}, /* AN82527 from Intel CP */
	{},
	};
	MODULE_DEVICE_TABLE(of, cc770_platform_table);

	static struct platform_driver cc770_platform_driver = {
	.driver = {
	.name = DRV_NAME,
	.owner = THIS_MODULE,
	.of_match_table = cc770_platform_table,
	},
	.probe = cc770_platform_probe,
	.remove = cc770_platform_remove,
	};

	module_platform_driver(cc770_platform_driver);