net/can: add driver for mscan family & mpc52xx_mscan (afa17a50) · Commits · e / devices / android_kernel_fairphone_FP3

Documentation/powerpc/dts-bindings/fsl/mpc5200.txt

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		@@ -178,3 +178,12 @@ External interrupts:
		external irq3: interrupts = <1 3 n>;
		'n' is sense (0: level high, 1: edge rising, 2: edge falling 3: level low)

		fsl,mpc5200-mscan nodes
		-----------------------
		In addition to the required compatible-, reg- and interrupt-properites, you can
		also specify which clock shall be used for the bus:

		- fsl,mscan-clk-src - a string describing the clock source. Valid values
		are "ip" for IP_CLK and "sys" for SYS_XTAL.
		"sys" is the default in case the property is not
		present.

drivers/net/can/Kconfig

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		@@ -108,6 +108,25 @@ config CAN_MCP251X
		---help---
		Driver for the Microchip MCP251x SPI CAN controllers.

		config CAN_MSCAN
		depends on CAN_DEV && (PPC \|\| M68K \|\| M68KNOMMU)
		tristate "Support for Freescale MSCAN based chips"
		---help---
		The Motorola Scalable Controller Area Network (MSCAN) definition
		is based on the MSCAN12 definition which is the specific
		implementation of the Motorola Scalable CAN concept targeted for
		the Motorola MC68HC12 Microcontroller Family.

		config CAN_MPC52XX
		tristate "Freescale MPC5xxx onboard CAN controller"
		depends on CAN_MSCAN && PPC_MPC52xx
		---help---
		If you say yes here you get support for Freescale's MPC52xx
		onboard dualCAN controller.

		This driver can also be built as a module. If so, the module
		will be called mpc5xxx_can.

		config CAN_DEBUG_DEVICES
		bool "CAN devices debugging messages"
		depends on CAN

drivers/net/can/Makefile

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		@@ -10,6 +10,7 @@ can-dev-y := dev.o
		obj-y += usb/

		obj-$(CONFIG_CAN_SJA1000) += sja1000/
		obj-$(CONFIG_CAN_MSCAN) += mscan/
		obj-$(CONFIG_CAN_AT91) += at91_can.o
		obj-$(CONFIG_CAN_TI_HECC) += ti_hecc.o
		obj-$(CONFIG_CAN_MCP251X) += mcp251x.o

drivers/net/can/mscan/Makefile

0 → 100644

+5 −0

Original line number	Diff line number	Diff line

		obj-$(CONFIG_CAN_MPC52XX) += mscan-mpc52xx.o
		mscan-mpc52xx-objs := mscan.o mpc52xx_can.o

		ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG

drivers/net/can/mscan/mpc52xx_can.c

0 → 100644

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Original line number	Diff line number	Diff line
		/*
		* CAN bus driver for the Freescale MPC5xxx embedded CPU.
		*
		* Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>,
		* Varma Electronics Oy
		* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
		* Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
		*
		* 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, write to the Free Software
		* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
		*/

		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/interrupt.h>
		#include <linux/platform_device.h>
		#include <linux/netdevice.h>
		#include <linux/can.h>
		#include <linux/can/dev.h>
		#include <linux/of_platform.h>
		#include <sysdev/fsl_soc.h>
		#include <linux/io.h>
		#include <asm/mpc52xx.h>

		#include "mscan.h"


		#define DRV_NAME "mpc5xxx_can"

		static struct of_device_id mpc52xx_cdm_ids[] __devinitdata = {
		{ .compatible = "fsl,mpc5200-cdm", },
		{ .compatible = "fsl,mpc5200b-cdm", },
		{}
		};

		/*
		* Get the frequency of the external oscillator clock connected
		* to the SYS_XTAL_IN pin, or return 0 if it cannot be determined.
		*/
		static unsigned int __devinit mpc52xx_can_xtal_freq(struct of_device *of)
		{
		struct mpc52xx_cdm __iomem *cdm;
		struct device_node *np_cdm;
		unsigned int freq;
		u32 val;

		freq = mpc5xxx_get_bus_frequency(of->node);
		if (!freq)
		return 0;

		/*
		* Determine SYS_XTAL_IN frequency from the clock domain settings
		*/
		np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids);
		if (!np_cdm) {
		dev_err(&of->dev, "can't get clock node!\n");
		return 0;
		}
		cdm = of_iomap(np_cdm, 0);
		of_node_put(np_cdm);

		if (in_8(&cdm->ipb_clk_sel) & 0x1)
		freq *= 2;
		val = in_be32(&cdm->rstcfg);
		if (val & (1 << 5))
		freq *= 8;
		else
		freq *= 4;
		if (val & (1 << 6))
		freq /= 12;
		else
		freq /= 16;

		iounmap(cdm);

		return freq;
		}

		/*
		* Get frequency of the MSCAN clock source
		*
		* Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock (IP_CLK)
		* can be selected. According to the MPC5200 user's manual, the oscillator
		* clock is the better choice as it has less jitter but due to a hardware
		* bug, it can not be selected for the old MPC5200 Rev. A chips.
		*/

		static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
		int clock_src)
		{
		unsigned int pvr;

		pvr = mfspr(SPRN_PVR);

		if (clock_src == MSCAN_CLKSRC_BUS \|\| pvr == 0x80822011)
		return mpc5xxx_get_bus_frequency(of->node);

		return mpc52xx_can_xtal_freq(of);
		}

		static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
		const struct of_device_id *id)
		{
		struct device_node *np = ofdev->node;
		struct net_device *dev;
		struct mscan_priv *priv;
		void __iomem *base;
		const char *clk_src;
		int err, irq, clock_src;

		base = of_iomap(ofdev->node, 0);
		if (!base) {
		dev_err(&ofdev->dev, "couldn't ioremap\n");
		err = -ENOMEM;
		goto exit_release_mem;
		}

		irq = irq_of_parse_and_map(np, 0);
		if (!irq) {
		dev_err(&ofdev->dev, "no irq found\n");
		err = -ENODEV;
		goto exit_unmap_mem;
		}

		dev = alloc_mscandev();
		if (!dev) {
		err = -ENOMEM;
		goto exit_dispose_irq;
		}

		priv = netdev_priv(dev);
		priv->reg_base = base;
		dev->irq = irq;

		/*
		* Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
		* (IP_CLK) can be selected as MSCAN clock source. According to
		* the MPC5200 user's manual, the oscillator clock is the better
		* choice as it has less jitter. For this reason, it is selected
		* by default.
		*/
		clk_src = of_get_property(np, "fsl,mscan-clk-src", NULL);
		if (clk_src && strcmp(clk_src, "ip") == 0)
		clock_src = MSCAN_CLKSRC_BUS;
		else
		clock_src = MSCAN_CLKSRC_XTAL;
		priv->can.clock.freq = mpc52xx_can_clock_freq(ofdev, clock_src);
		if (!priv->can.clock.freq) {
		dev_err(&ofdev->dev, "couldn't get MSCAN clock frequency\n");
		err = -ENODEV;
		goto exit_free_mscan;
		}

		SET_NETDEV_DEV(dev, &ofdev->dev);

		err = register_mscandev(dev, clock_src);
		if (err) {
		dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
		DRV_NAME, err);
		goto exit_free_mscan;
		}

		dev_set_drvdata(&ofdev->dev, dev);

		dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n",
		priv->reg_base, dev->irq, priv->can.clock.freq);

		return 0;

		exit_free_mscan:
		free_candev(dev);
		exit_dispose_irq:
		irq_dispose_mapping(irq);
		exit_unmap_mem:
		iounmap(base);
		exit_release_mem:
		return err;
		}

		static int __devexit mpc5xxx_can_remove(struct of_device *ofdev)
		{
		struct net_device *dev = dev_get_drvdata(&ofdev->dev);
		struct mscan_priv *priv = netdev_priv(dev);

		dev_set_drvdata(&ofdev->dev, NULL);

		unregister_mscandev(dev);
		iounmap(priv->reg_base);
		irq_dispose_mapping(dev->irq);
		free_candev(dev);

		return 0;
		}

		#ifdef CONFIG_PM
		static struct mscan_regs saved_regs;
		static int mpc5xxx_can_suspend(struct of_device *ofdev, pm_message_t state)
		{
		struct net_device *dev = dev_get_drvdata(&ofdev->dev);
		struct mscan_priv *priv = netdev_priv(dev);
		struct mscan_regs regs = (struct mscan_regs )priv->reg_base;

		_memcpy_fromio(&saved_regs, regs, sizeof(*regs));

		return 0;
		}

		static int mpc5xxx_can_resume(struct of_device *ofdev)
		{
		struct net_device *dev = dev_get_drvdata(&ofdev->dev);
		struct mscan_priv *priv = netdev_priv(dev);
		struct mscan_regs regs = (struct mscan_regs )priv->reg_base;

		regs->canctl0 \|= MSCAN_INITRQ;
		while ((regs->canctl1 & MSCAN_INITAK) == 0)
		udelay(10);

		regs->canctl1 = saved_regs.canctl1;
		regs->canbtr0 = saved_regs.canbtr0;
		regs->canbtr1 = saved_regs.canbtr1;
		regs->canidac = saved_regs.canidac;

		/* restore masks, buffers etc. */
		_memcpy_toio(&regs->canidar1_0, (void *)&saved_regs.canidar1_0,
		sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0));

		regs->canctl0 &= ~MSCAN_INITRQ;
		regs->cantbsel = saved_regs.cantbsel;
		regs->canrier = saved_regs.canrier;
		regs->cantier = saved_regs.cantier;
		regs->canctl0 = saved_regs.canctl0;

		return 0;
		}
		#endif

		static struct of_device_id __devinitdata mpc5xxx_can_table[] = {
		{.compatible = "fsl,mpc5200-mscan"},
		{.compatible = "fsl,mpc5200b-mscan"},
		{},
		};

		static struct of_platform_driver mpc5xxx_can_driver = {
		.owner = THIS_MODULE,
		.name = "mpc5xxx_can",
		.probe = mpc5xxx_can_probe,
		.remove = __devexit_p(mpc5xxx_can_remove),
		#ifdef CONFIG_PM
		.suspend = mpc5xxx_can_suspend,
		.resume = mpc5xxx_can_resume,
		#endif
		.match_table = mpc5xxx_can_table,
		};

		static int __init mpc5xxx_can_init(void)
		{
		return of_register_platform_driver(&mpc5xxx_can_driver);
		}
		module_init(mpc5xxx_can_init);

		static void __exit mpc5xxx_can_exit(void)
		{
		return of_unregister_platform_driver(&mpc5xxx_can_driver);
		};
		module_exit(mpc5xxx_can_exit);

		MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
		MODULE_DESCRIPTION("Freescale MPC5200 CAN driver");
		MODULE_LICENSE("GPL v2");