can: SJA1000 generic platform bus driver

This driver adds support for the SJA1000 chips connected to the
"platform bus", which can be found on various embedded systems.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/can/Kconfig

@@ -41,6 +41,16 @@ config CAN_SJA1000
 	---help---
 	  Driver for the SJA1000 CAN controllers from Philips or NXP
 
+config CAN_SJA1000_PLATFORM
+	depends on CAN_SJA1000
+	tristate "Generic Platform Bus based SJA1000 driver"
+	---help---
+	  This driver adds support for the SJA1000 chips connected to
+	  the "platform bus" (Linux abstraction for directly to the
+	  processor attached devices).  Which can be found on various
+	  boards from Phytec (http://www.phytec.de) like the PCM027,
+	  PCM038.
+
 config CAN_DEBUG_DEVICES
 	bool "CAN devices debugging messages"
 	depends on CAN

drivers/net/can/sja1000/Makefile

@@ -3,5 +3,6 @@
 #
 
 obj-$(CONFIG_CAN_SJA1000) += sja1000.o
+obj-$(CONFIG_CAN_SJA1000_PLATFORM) += sja1000_platform.o
 
 ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG

drivers/net/can/sja1000/sja1000_platform.c

+/*
+ * 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, 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/netdevice.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/platform/sja1000.h>
+#include <linux/io.h>
+
+#include "sja1000.h"
+
+#define DRV_NAME "sja1000_platform"
+
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
+MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
+MODULE_LICENSE("GPL v2");
+
+static u8 sp_read_reg(const struct net_device *dev, int reg)
+{
+	return ioread8((void __iomem *)(dev->base_addr + reg));
+}
+
+static void sp_write_reg(const struct net_device *dev, int reg, u8 val)
+{
+	iowrite8(val, (void __iomem *)(dev->base_addr + reg));
+}
+
+static int sp_probe(struct platform_device *pdev)
+{
+	int err;
+	void __iomem *addr;
+	struct net_device *dev;
+	struct sja1000_priv *priv;
+	struct resource *res_mem, *res_irq;
+	struct sja1000_platform_data *pdata;
+
+	pdata = pdev->dev.platform_data;
+	if (!pdata) {
+		dev_err(&pdev->dev, "No platform data provided!\n");
+		err = -ENODEV;
+		goto exit;
+	}
+
+	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res_mem || !res_irq) {
+		err = -ENODEV;
+		goto exit;
+	}
+
+	if (!request_mem_region(res_mem->start, resource_size(res_mem),
+				DRV_NAME)) {
+		err = -EBUSY;
+		goto exit;
+	}
+
+	addr = ioremap_nocache(res_mem->start, resource_size(res_mem));
+	if (!addr) {
+		err = -ENOMEM;
+		goto exit_release;
+	}
+
+	dev = alloc_sja1000dev(0);
+	if (!dev) {
+		err = -ENOMEM;
+		goto exit_iounmap;
+	}
+	priv = netdev_priv(dev);
+
+	dev->base_addr = (unsigned long)addr;
+	dev->irq = res_irq->start;
+	priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
+	priv->read_reg = sp_read_reg;
+	priv->write_reg = sp_write_reg;
+	priv->can.clock.freq = pdata->clock;
+	priv->ocr = pdata->ocr;
+	priv->cdr = pdata->cdr;
+
+	dev_set_drvdata(&pdev->dev, 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 (base_addr=%#lx, irq=%d)\n",
+		 DRV_NAME, dev->base_addr, dev->irq);
+	return 0;
+
+ exit_free:
+	free_sja1000dev(dev);
+ exit_iounmap:
+	iounmap(addr);
+ exit_release:
+	release_mem_region(res_mem->start, resource_size(res_mem));
+ exit:
+	return err;
+}
+
+static int sp_remove(struct platform_device *pdev)
+{
+	struct net_device *dev = dev_get_drvdata(&pdev->dev);
+	struct resource *res;
+
+	unregister_sja1000dev(dev);
+	dev_set_drvdata(&pdev->dev, NULL);
+
+	if (dev->base_addr)
+		iounmap((void __iomem *)dev->base_addr);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+
+	free_sja1000dev(dev);
+
+	return 0;
+}
+
+static struct platform_driver sp_driver = {
+	.probe = sp_probe,
+	.remove = sp_remove,
+	.driver = {
+		.name = DRV_NAME,
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init sp_init(void)
+{
+	return platform_driver_register(&sp_driver);
+}
+
+static void __exit sp_exit(void)
+{
+	platform_driver_unregister(&sp_driver);
+}
+
+module_init(sp_init);
+module_exit(sp_exit);

include/linux/can/platform/sja1000.h

+#ifndef _CAN_PLATFORM_SJA1000_H_
+#define _CAN_PLATFORM_SJA1000_H_
+
+/* clock divider register */
+#define CDR_CLKOUT_MASK 0x07
+#define CDR_CLK_OFF	0x08 /* Clock off (CLKOUT pin) */
+#define CDR_RXINPEN	0x20 /* TX1 output is RX irq output */
+#define CDR_CBP		0x40 /* CAN input comparator bypass */
+#define CDR_PELICAN	0x80 /* PeliCAN mode */
+
+/* output control register */
+#define OCR_MODE_BIPHASE  0x00
+#define OCR_MODE_TEST     0x01
+#define OCR_MODE_NORMAL   0x02
+#define OCR_MODE_CLOCK    0x03
+#define OCR_TX0_INVERT    0x04
+#define OCR_TX0_PULLDOWN  0x08
+#define OCR_TX0_PULLUP    0x10
+#define OCR_TX0_PUSHPULL  0x18
+#define OCR_TX1_INVERT    0x20
+#define OCR_TX1_PULLDOWN  0x40
+#define OCR_TX1_PULLUP    0x80
+#define OCR_TX1_PUSHPULL  0xc0
+
+struct sja1000_platform_data {
+	u32 clock;	/* CAN bus oscillator frequency in Hz */
+
+	u8 ocr;		/* output control register */
+	u8 cdr;		/* clock divider register */
+};
+
+#endif	/* !_CAN_PLATFORM_SJA1000_H_ */