drivers/net/can/c_can/c_can_platform.c - pub/scm/linux/kernel/git/monstr/linux - Git at Google

 /*
  * Platform CAN bus driver for Bosch C_CAN controller
  *
  * Copyright (C) 2010 ST Microelectronics
  * Bhupesh Sharma <bhupesh.sharma@st.com>
  *
  * Borrowed heavily from the C_CAN driver originally written by:
  * Copyright (C) 2007
  * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de>
  * - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch>
  *
  * Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B.
  * Bosch C_CAN user manual can be obtained from:
  * http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/
  * users_manual_c_can.pdf
  *
  * This file is licensed under the terms of the GNU General Public
  * License version 2. This program is licensed "as is" without any
  * warranty of any kind, whether express or implied.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
 #include <linux/if_ether.h>
 #include <linux/list.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/of.h>
 #include <linux/of_device.h>

 #include <linux/can/dev.h>

 #include "c_can.h"

 #define CAN_RAMINIT_START_MASK(i)	(0x001 << (i))
 #define CAN_RAMINIT_DONE_MASK(i)	(0x100 << (i))
 #define CAN_RAMINIT_ALL_MASK(i)		(0x101 << (i))
 static DEFINE_SPINLOCK(raminit_lock);
 /*
  * 16-bit c_can registers can be arranged differently in the memory
  * architecture of different implementations. For example: 16-bit
  * registers can be aligned to a 16-bit boundary or 32-bit boundary etc.
  * Handle the same by providing a common read/write interface.
  */
 static u16 c_can_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv,
 						enum reg index)
 {
 	return readw(priv->base + priv->regs[index]);
 }

 static void c_can_plat_write_reg_aligned_to_16bit(struct c_can_priv *priv,
 						enum reg index, u16 val)
 {
 	writew(val, priv->base + priv->regs[index]);
 }

 static u16 c_can_plat_read_reg_aligned_to_32bit(struct c_can_priv *priv,
 						enum reg index)
 {
 	return readw(priv->base + 2 * priv->regs[index]);
 }

 static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
 						enum reg index, u16 val)
 {
 	writew(val, priv->base + 2 * priv->regs[index]);
 }

 static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask,
 				  u32 val)
 {
 	/* We look only at the bits of our instance. */
 	val &= mask;
 	while ((readl(priv->raminit_ctrlreg) & mask) != val)
 		udelay(1);
 }

 static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
 {
 	u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
 	u32 ctrl;

 	spin_lock(&raminit_lock);

 	ctrl = readl(priv->raminit_ctrlreg);
 	/* We clear the done and start bit first. The start bit is
 	 * looking at the 0 -> transition, but is not self clearing;
 	 * And we clear the init done bit as well.
 	 */
 	ctrl &= ~CAN_RAMINIT_START_MASK(priv->instance);
 	ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
 	writel(ctrl, priv->raminit_ctrlreg);
 	ctrl &= ~CAN_RAMINIT_DONE_MASK(priv->instance);
 	c_can_hw_raminit_wait(priv, ctrl, mask);

 	if (enable) {
 		/* Set start bit and wait for the done bit. */
 		ctrl |= CAN_RAMINIT_START_MASK(priv->instance);
 		writel(ctrl, priv->raminit_ctrlreg);
 		ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
 		c_can_hw_raminit_wait(priv, ctrl, mask);
 	}
 	spin_unlock(&raminit_lock);
 }

 static struct platform_device_id c_can_id_table[] = {
 	[BOSCH_C_CAN_PLATFORM] = {
 		.name = KBUILD_MODNAME,
 		.driver_data = BOSCH_C_CAN,
 	},
 	[BOSCH_C_CAN] = {
 		.name = "c_can",
 		.driver_data = BOSCH_C_CAN,
 	},
 	[BOSCH_D_CAN] = {
 		.name = "d_can",
 		.driver_data = BOSCH_D_CAN,
 	}, {
 	}
 };
 MODULE_DEVICE_TABLE(platform, c_can_id_table);

 static const struct of_device_id c_can_of_table[] = {
 	{ .compatible = "bosch,c_can", .data = &c_can_id_table[BOSCH_C_CAN] },
 	{ .compatible = "bosch,d_can", .data = &c_can_id_table[BOSCH_D_CAN] },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, c_can_of_table);

 static int c_can_plat_probe(struct platform_device *pdev)
 {
 	int ret;
 	void __iomem *addr;
 	struct net_device *dev;
 	struct c_can_priv *priv;
 	const struct of_device_id *match;
 	const struct platform_device_id *id;
 	struct resource *mem, *res;
 	int irq;
 	struct clk *clk;

 	if (pdev->dev.of_node) {
 		match = of_match_device(c_can_of_table, &pdev->dev);
 		if (!match) {
 			dev_err(&pdev->dev, "Failed to find matching dt id\n");
 			ret = -EINVAL;
 			goto exit;
 		}
 		id = match->data;
 	} else {
 		id = platform_get_device_id(pdev);
 	}

 	/* get the appropriate clk */
 	clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "no clock defined\n");
 		ret = -ENODEV;
 		goto exit;
 	}

 	/* get the platform data */
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_irq(pdev, 0);
 	if (!mem || irq <= 0) {
 		ret = -ENODEV;
 		goto exit_free_clk;
 	}

 	if (!request_mem_region(mem->start, resource_size(mem),
 				KBUILD_MODNAME)) {
 		dev_err(&pdev->dev, "resource unavailable\n");
 		ret = -ENODEV;
 		goto exit_free_clk;
 	}

 	addr = ioremap(mem->start, resource_size(mem));
 	if (!addr) {
 		dev_err(&pdev->dev, "failed to map can port\n");
 		ret = -ENOMEM;
 		goto exit_release_mem;
 	}

 	/* allocate the c_can device */
 	dev = alloc_c_can_dev();
 	if (!dev) {
 		ret = -ENOMEM;
 		goto exit_iounmap;
 	}

 	priv = netdev_priv(dev);
 	switch (id->driver_data) {
 	case BOSCH_C_CAN:
 		priv->regs = reg_map_c_can;
 		switch (mem->flags & IORESOURCE_MEM_TYPE_MASK) {
 		case IORESOURCE_MEM_32BIT:
 			priv->read_reg = c_can_plat_read_reg_aligned_to_32bit;
 			priv->write_reg = c_can_plat_write_reg_aligned_to_32bit;
 			break;
 		case IORESOURCE_MEM_16BIT:
 		default:
 			priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 			priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
 			break;
 		}
 		break;
 	case BOSCH_D_CAN:
 		priv->regs = reg_map_d_can;
 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 		priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 		priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;

 		if (pdev->dev.of_node)
 			priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
 		else
 			priv->instance = pdev->id;

 		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 		priv->raminit_ctrlreg = devm_ioremap_resource(&pdev->dev, res);
 		if (IS_ERR(priv->raminit_ctrlreg) || priv->instance < 0)
 			dev_info(&pdev->dev, "control memory is not used for raminit\n");
 		else
 			priv->raminit = c_can_hw_raminit;
 		break;
 	default:
 		ret = -EINVAL;
 		goto exit_free_device;
 	}

 	dev->irq = irq;
 	priv->base = addr;
 	priv->device = &pdev->dev;
 	priv->can.clock.freq = clk_get_rate(clk);
 	priv->priv = clk;
 	priv->type = id->driver_data;

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

 	ret = register_c_can_dev(dev);
 	if (ret) {
 		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
 			KBUILD_MODNAME, ret);
 		goto exit_free_device;
 	}

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

 exit_free_device:
 	free_c_can_dev(dev);
 exit_iounmap:
 	iounmap(addr);
 exit_release_mem:
 	release_mem_region(mem->start, resource_size(mem));
 exit_free_clk:
 	clk_put(clk);
 exit:
 	dev_err(&pdev->dev, "probe failed\n");

 	return ret;
 }

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

 	unregister_c_can_dev(dev);

 	free_c_can_dev(dev);
 	iounmap(priv->base);

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

 	clk_put(priv->priv);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int c_can_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	int ret;
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct c_can_priv *priv = netdev_priv(ndev);

 	if (priv->type != BOSCH_D_CAN) {
 		dev_warn(&pdev->dev, "Not supported\n");
 		return 0;
 	}

 	if (netif_running(ndev)) {
 		netif_stop_queue(ndev);
 		netif_device_detach(ndev);
 	}

 	ret = c_can_power_down(ndev);
 	if (ret) {
 		netdev_err(ndev, "failed to enter power down mode\n");
 		return ret;
 	}

 	priv->can.state = CAN_STATE_SLEEPING;

 	return 0;
 }

 static int c_can_resume(struct platform_device *pdev)
 {
 	int ret;
 	struct net_device *ndev = platform_get_drvdata(pdev);
 	struct c_can_priv *priv = netdev_priv(ndev);

 	if (priv->type != BOSCH_D_CAN) {
 		dev_warn(&pdev->dev, "Not supported\n");
 		return 0;
 	}

 	ret = c_can_power_up(ndev);
 	if (ret) {
 		netdev_err(ndev, "Still in power down mode\n");
 		return ret;
 	}

 	priv->can.state = CAN_STATE_ERROR_ACTIVE;

 	if (netif_running(ndev)) {
 		netif_device_attach(ndev);
 		netif_start_queue(ndev);
 	}

 	return 0;
 }
 #else
 #define c_can_suspend NULL
 #define c_can_resume NULL
 #endif

 static struct platform_driver c_can_plat_driver = {
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.owner = THIS_MODULE,
 		.of_match_table = c_can_of_table,
 	},
 	.probe = c_can_plat_probe,
 	.remove = c_can_plat_remove,
 	.suspend = c_can_suspend,
 	.resume = c_can_resume,
 	.id_table = c_can_id_table,
 };

 module_platform_driver(c_can_plat_driver);

 MODULE_AUTHOR("Bhupesh Sharma <bhupesh.sharma@st.com>");
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Platform CAN bus driver for Bosch C_CAN controller");
	/*
	* Platform CAN bus driver for Bosch C_CAN controller
	*
	* Copyright (C) 2010 ST Microelectronics
	* Bhupesh Sharma <bhupesh.sharma@st.com>
	*
	* Borrowed heavily from the C_CAN driver originally written by:
	* Copyright (C) 2007
	* - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de>
	* - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch>
	*
	* Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B.
	* Bosch C_CAN user manual can be obtained from:
	* http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/
	* users_manual_c_can.pdf
	*
	* This file is licensed under the terms of the GNU General Public
	* License version 2. This program is licensed "as is" without any
	* warranty of any kind, whether express or implied.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <linux/delay.h>
	#include <linux/netdevice.h>
	#include <linux/if_arp.h>
	#include <linux/if_ether.h>
	#include <linux/list.h>
	#include <linux/io.h>
	#include <linux/platform_device.h>
	#include <linux/clk.h>
	#include <linux/of.h>
	#include <linux/of_device.h>

	#include <linux/can/dev.h>

	#include "c_can.h"

	#define CAN_RAMINIT_START_MASK(i) (0x001 << (i))
	#define CAN_RAMINIT_DONE_MASK(i) (0x100 << (i))
	#define CAN_RAMINIT_ALL_MASK(i) (0x101 << (i))
	static DEFINE_SPINLOCK(raminit_lock);
	/*
	* 16-bit c_can registers can be arranged differently in the memory
	* architecture of different implementations. For example: 16-bit
	* registers can be aligned to a 16-bit boundary or 32-bit boundary etc.
	* Handle the same by providing a common read/write interface.
	*/
	static u16 c_can_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv,
	enum reg index)
	{
	return readw(priv->base + priv->regs[index]);
	}

	static void c_can_plat_write_reg_aligned_to_16bit(struct c_can_priv *priv,
	enum reg index, u16 val)
	{
	writew(val, priv->base + priv->regs[index]);
	}

	static u16 c_can_plat_read_reg_aligned_to_32bit(struct c_can_priv *priv,
	enum reg index)
	{
	return readw(priv->base + 2 * priv->regs[index]);
	}

	static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
	enum reg index, u16 val)
	{
	writew(val, priv->base + 2 * priv->regs[index]);
	}

	static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask,
	u32 val)
	{
	/* We look only at the bits of our instance. */
	val &= mask;
	while ((readl(priv->raminit_ctrlreg) & mask) != val)
	udelay(1);
	}

	static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
	{
	u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
	u32 ctrl;

	spin_lock(&raminit_lock);

	ctrl = readl(priv->raminit_ctrlreg);
	/* We clear the done and start bit first. The start bit is
	* looking at the 0 -> transition, but is not self clearing;
	* And we clear the init done bit as well.
	*/
	ctrl &= ~CAN_RAMINIT_START_MASK(priv->instance);
	ctrl \|= CAN_RAMINIT_DONE_MASK(priv->instance);
	writel(ctrl, priv->raminit_ctrlreg);
	ctrl &= ~CAN_RAMINIT_DONE_MASK(priv->instance);
	c_can_hw_raminit_wait(priv, ctrl, mask);

	if (enable) {
	/* Set start bit and wait for the done bit. */
	ctrl \|= CAN_RAMINIT_START_MASK(priv->instance);
	writel(ctrl, priv->raminit_ctrlreg);
	ctrl \|= CAN_RAMINIT_DONE_MASK(priv->instance);
	c_can_hw_raminit_wait(priv, ctrl, mask);
	}
	spin_unlock(&raminit_lock);
	}

	static struct platform_device_id c_can_id_table[] = {
	[BOSCH_C_CAN_PLATFORM] = {
	.name = KBUILD_MODNAME,
	.driver_data = BOSCH_C_CAN,
	},
	[BOSCH_C_CAN] = {
	.name = "c_can",
	.driver_data = BOSCH_C_CAN,
	},
	[BOSCH_D_CAN] = {
	.name = "d_can",
	.driver_data = BOSCH_D_CAN,
	}, {
	}
	};
	MODULE_DEVICE_TABLE(platform, c_can_id_table);

	static const struct of_device_id c_can_of_table[] = {
	{ .compatible = "bosch,c_can", .data = &c_can_id_table[BOSCH_C_CAN] },
	{ .compatible = "bosch,d_can", .data = &c_can_id_table[BOSCH_D_CAN] },
	{ /* sentinel */ },
	};
	MODULE_DEVICE_TABLE(of, c_can_of_table);

	static int c_can_plat_probe(struct platform_device *pdev)
	{
	int ret;
	void __iomem *addr;
	struct net_device *dev;
	struct c_can_priv *priv;
	const struct of_device_id *match;
	const struct platform_device_id *id;
	struct resource mem, res;
	int irq;
	struct clk *clk;

	if (pdev->dev.of_node) {
	match = of_match_device(c_can_of_table, &pdev->dev);
	if (!match) {
	dev_err(&pdev->dev, "Failed to find matching dt id\n");
	ret = -EINVAL;
	goto exit;
	}
	id = match->data;
	} else {
	id = platform_get_device_id(pdev);
	}

	/* get the appropriate clk */
	clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(clk)) {
	dev_err(&pdev->dev, "no clock defined\n");
	ret = -ENODEV;
	goto exit;
	}

	/* get the platform data */
	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
	if (!mem \|\| irq <= 0) {
	ret = -ENODEV;
	goto exit_free_clk;
	}

	if (!request_mem_region(mem->start, resource_size(mem),
	KBUILD_MODNAME)) {
	dev_err(&pdev->dev, "resource unavailable\n");
	ret = -ENODEV;
	goto exit_free_clk;
	}

	addr = ioremap(mem->start, resource_size(mem));
	if (!addr) {
	dev_err(&pdev->dev, "failed to map can port\n");
	ret = -ENOMEM;
	goto exit_release_mem;
	}

	/* allocate the c_can device */
	dev = alloc_c_can_dev();
	if (!dev) {
	ret = -ENOMEM;
	goto exit_iounmap;
	}

	priv = netdev_priv(dev);
	switch (id->driver_data) {
	case BOSCH_C_CAN:
	priv->regs = reg_map_c_can;
	switch (mem->flags & IORESOURCE_MEM_TYPE_MASK) {
	case IORESOURCE_MEM_32BIT:
	priv->read_reg = c_can_plat_read_reg_aligned_to_32bit;
	priv->write_reg = c_can_plat_write_reg_aligned_to_32bit;
	break;
	case IORESOURCE_MEM_16BIT:
	default:
	priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
	priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
	break;
	}
	break;
	case BOSCH_D_CAN:
	priv->regs = reg_map_d_can;
	priv->can.ctrlmode_supported \|= CAN_CTRLMODE_3_SAMPLES;
	priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
	priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;

	if (pdev->dev.of_node)
	priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
	else
	priv->instance = pdev->id;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	priv->raminit_ctrlreg = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(priv->raminit_ctrlreg) \|\| priv->instance < 0)
	dev_info(&pdev->dev, "control memory is not used for raminit\n");
	else
	priv->raminit = c_can_hw_raminit;
	break;
	default:
	ret = -EINVAL;
	goto exit_free_device;
	}

	dev->irq = irq;
	priv->base = addr;
	priv->device = &pdev->dev;
	priv->can.clock.freq = clk_get_rate(clk);
	priv->priv = clk;
	priv->type = id->driver_data;

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

	ret = register_c_can_dev(dev);
	if (ret) {
	dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
	KBUILD_MODNAME, ret);
	goto exit_free_device;
	}

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

	exit_free_device:
	free_c_can_dev(dev);
	exit_iounmap:
	iounmap(addr);
	exit_release_mem:
	release_mem_region(mem->start, resource_size(mem));
	exit_free_clk:
	clk_put(clk);
	exit:
	dev_err(&pdev->dev, "probe failed\n");

	return ret;
	}

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

	unregister_c_can_dev(dev);

	free_c_can_dev(dev);
	iounmap(priv->base);

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

	clk_put(priv->priv);

	return 0;
	}

	#ifdef CONFIG_PM
	static int c_can_suspend(struct platform_device *pdev, pm_message_t state)
	{
	int ret;
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct c_can_priv *priv = netdev_priv(ndev);

	if (priv->type != BOSCH_D_CAN) {
	dev_warn(&pdev->dev, "Not supported\n");
	return 0;
	}

	if (netif_running(ndev)) {
	netif_stop_queue(ndev);
	netif_device_detach(ndev);
	}

	ret = c_can_power_down(ndev);
	if (ret) {
	netdev_err(ndev, "failed to enter power down mode\n");
	return ret;
	}

	priv->can.state = CAN_STATE_SLEEPING;

	return 0;
	}

	static int c_can_resume(struct platform_device *pdev)
	{
	int ret;
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct c_can_priv *priv = netdev_priv(ndev);

	if (priv->type != BOSCH_D_CAN) {
	dev_warn(&pdev->dev, "Not supported\n");
	return 0;
	}

	ret = c_can_power_up(ndev);
	if (ret) {
	netdev_err(ndev, "Still in power down mode\n");
	return ret;
	}

	priv->can.state = CAN_STATE_ERROR_ACTIVE;

	if (netif_running(ndev)) {
	netif_device_attach(ndev);
	netif_start_queue(ndev);
	}

	return 0;
	}
	#else
	#define c_can_suspend NULL
	#define c_can_resume NULL
	#endif

	static struct platform_driver c_can_plat_driver = {
	.driver = {
	.name = KBUILD_MODNAME,
	.owner = THIS_MODULE,
	.of_match_table = c_can_of_table,
	},
	.probe = c_can_plat_probe,
	.remove = c_can_plat_remove,
	.suspend = c_can_suspend,
	.resume = c_can_resume,
	.id_table = c_can_id_table,
	};

	module_platform_driver(c_can_plat_driver);

	MODULE_AUTHOR("Bhupesh Sharma <bhupesh.sharma@st.com>");
	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("Platform CAN bus driver for Bosch C_CAN controller");