can: tscan1: add driver for TS-CAN1 boards

Add driver for Technologic Systems TS-CAN1 PC104 peripheral boards.
Signed-off-by: Andre B. Oliveira <anbadeol@gmail.com>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/can/sja1000/Kconfig

@@ -58,4 +58,16 @@ config CAN_PLX_PCI
 	   - esd CAN-PCIe/2000
 	   - Marathon CAN-bus-PCI card (http://www.marathon.ru/)
 	   - TEWS TECHNOLOGIES TPMC810 card (http://www.tews.com/)
+
+config CAN_TSCAN1
+	tristate "TS-CAN1 PC104 boards"
+	depends on ISA
+	help
+	This driver is for Technologic Systems' TSCAN-1 PC104 boards.
+	http://www.embeddedarm.com/products/board-detail.php?product=TS-CAN1
+	The driver supports multiple boards and automatically configures them:
+	PLD IO base addresses are read from jumpers JP1 and JP2,
+	IRQ numbers are read from jumpers JP4 and JP5,
+	SJA1000 IO base addresses are chosen heuristically (first that works).
+
 endif

drivers/net/can/sja1000/Makefile

@@ -9,5 +9,6 @@ obj-$(CONFIG_CAN_SJA1000_OF_PLATFORM) += sja1000_of_platform.o
 obj-$(CONFIG_CAN_EMS_PCI) += ems_pci.o
 obj-$(CONFIG_CAN_KVASER_PCI) += kvaser_pci.o
 obj-$(CONFIG_CAN_PLX_PCI) += plx_pci.o
+obj-$(CONFIG_CAN_TSCAN1) += tscan1.o
 
 ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG

drivers/net/can/sja1000/tscan1.c

+/*
+ * tscan1.c: driver for Technologic Systems TS-CAN1 PC104 boards
+ *
+ * Copyright 2010 Andre B. Oliveira
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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/>.
+ */
+
+/*
+ * References:
+ * - Getting started with TS-CAN1, Technologic Systems, Jun 2009
+ *	http://www.embeddedarm.com/documentation/ts-can1-manual.pdf
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/isa.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include "sja1000.h"
+
+MODULE_DESCRIPTION("Driver for Technologic Systems TS-CAN1 PC104 boards");
+MODULE_AUTHOR("Andre B. Oliveira <anbadeol@gmail.com>");
+MODULE_LICENSE("GPL");
+
+/* Maximum number of boards (one in each JP1:JP2 setting of IO address) */
+#define TSCAN1_MAXDEV 4
+
+/* PLD registers address offsets */
+#define TSCAN1_ID1	0
+#define TSCAN1_ID2	1
+#define TSCAN1_VERSION	2
+#define TSCAN1_LED	3
+#define TSCAN1_PAGE	4
+#define TSCAN1_MODE	5
+#define TSCAN1_JUMPERS	6
+
+/* PLD board identifier registers magic values */
+#define TSCAN1_ID1_VALUE 0xf6
+#define TSCAN1_ID2_VALUE 0xb9
+
+/* PLD mode register SJA1000 IO enable bit */
+#define TSCAN1_MODE_ENABLE 0x40
+
+/* PLD jumpers register bits */
+#define TSCAN1_JP4 0x10
+#define TSCAN1_JP5 0x20
+
+/* PLD IO base addresses start */
+#define TSCAN1_PLD_ADDRESS 0x150
+
+/* PLD register space size */
+#define TSCAN1_PLD_SIZE 8
+
+/* SJA1000 register space size */
+#define TSCAN1_SJA1000_SIZE 32
+
+/* SJA1000 crystal frequency (16MHz) */
+#define TSCAN1_SJA1000_XTAL 16000000
+
+/* SJA1000 IO base addresses */
+static const unsigned short tscan1_sja1000_addresses[] __devinitconst = {
+	0x100, 0x120, 0x180, 0x1a0, 0x200, 0x240, 0x280, 0x320
+};
+
+/* Read SJA1000 register */
+static u8 tscan1_read(const struct sja1000_priv *priv, int reg)
+{
+	return inb((unsigned long)priv->reg_base + reg);
+}
+
+/* Write SJA1000 register */
+static void tscan1_write(const struct sja1000_priv *priv, int reg, u8 val)
+{
+	outb(val, (unsigned long)priv->reg_base + reg);
+}
+
+/* Probe for a TS-CAN1 board with JP2:JP1 jumper setting ID */
+static int __devinit tscan1_probe(struct device *dev, unsigned id)
+{
+	struct net_device *netdev;
+	struct sja1000_priv *priv;
+	unsigned long pld_base, sja1000_base;
+	int irq, i;
+
+	pld_base = TSCAN1_PLD_ADDRESS + id * TSCAN1_PLD_SIZE;
+	if (!request_region(pld_base, TSCAN1_PLD_SIZE, dev_name(dev)))
+		return -EBUSY;
+
+	if (inb(pld_base + TSCAN1_ID1) != TSCAN1_ID1_VALUE ||
+	    inb(pld_base + TSCAN1_ID2) != TSCAN1_ID2_VALUE) {
+		release_region(pld_base, TSCAN1_PLD_SIZE);
+		return -ENODEV;
+	}
+
+	switch (inb(pld_base + TSCAN1_JUMPERS) & (TSCAN1_JP4 | TSCAN1_JP5)) {
+	case TSCAN1_JP4:
+		irq = 6;
+		break;
+	case TSCAN1_JP5:
+		irq = 7;
+		break;
+	case TSCAN1_JP4 | TSCAN1_JP5:
+		irq = 5;
+		break;
+	default:
+		dev_err(dev, "invalid JP4:JP5 setting (no IRQ)\n");
+		release_region(pld_base, TSCAN1_PLD_SIZE);
+		return -EINVAL;
+	}
+
+	netdev = alloc_sja1000dev(0);
+	if (!netdev) {
+		release_region(pld_base, TSCAN1_PLD_SIZE);
+		return -ENOMEM;
+	}
+
+	dev_set_drvdata(dev, netdev);
+	SET_NETDEV_DEV(netdev, dev);
+
+	netdev->base_addr = pld_base;
+	netdev->irq = irq;
+
+	priv = netdev_priv(netdev);
+	priv->read_reg = tscan1_read;
+	priv->write_reg = tscan1_write;
+	priv->can.clock.freq = TSCAN1_SJA1000_XTAL / 2;
+	priv->cdr = CDR_CBP | CDR_CLK_OFF;
+	priv->ocr = OCR_TX0_PUSHPULL;
+
+	/* Select the first SJA1000 IO address that is free and that works */
+	for (i = 0; i < ARRAY_SIZE(tscan1_sja1000_addresses); i++) {
+		sja1000_base = tscan1_sja1000_addresses[i];
+		if (!request_region(sja1000_base, TSCAN1_SJA1000_SIZE,
+								dev_name(dev)))
+			continue;
+
+		/* Set SJA1000 IO base address and enable it */
+		outb(TSCAN1_MODE_ENABLE | i, pld_base + TSCAN1_MODE);
+
+		priv->reg_base = (void __iomem *)sja1000_base;
+		if (!register_sja1000dev(netdev)) {
+			/* SJA1000 probe succeeded; turn LED off and return */
+			outb(0, pld_base + TSCAN1_LED);
+			netdev_info(netdev, "TS-CAN1 at 0x%lx 0x%lx irq %d\n",
+						pld_base, sja1000_base, irq);
+			return 0;
+		}
+
+		/* SJA1000 probe failed; release and try next address */
+		outb(0, pld_base + TSCAN1_MODE);
+		release_region(sja1000_base, TSCAN1_SJA1000_SIZE);
+	}
+
+	dev_err(dev, "failed to assign SJA1000 IO address\n");
+	dev_set_drvdata(dev, NULL);
+	free_sja1000dev(netdev);
+	release_region(pld_base, TSCAN1_PLD_SIZE);
+	return -ENXIO;
+}
+
+static int __devexit tscan1_remove(struct device *dev, unsigned id /*unused*/)
+{
+	struct net_device *netdev;
+	struct sja1000_priv *priv;
+	unsigned long pld_base, sja1000_base;
+
+	netdev = dev_get_drvdata(dev);
+	unregister_sja1000dev(netdev);
+	dev_set_drvdata(dev, NULL);
+
+	priv = netdev_priv(netdev);
+	pld_base = netdev->base_addr;
+	sja1000_base = (unsigned long)priv->reg_base;
+
+	outb(0, pld_base + TSCAN1_MODE);	/* disable SJA1000 IO space */
+
+	release_region(sja1000_base, TSCAN1_SJA1000_SIZE);
+	release_region(pld_base, TSCAN1_PLD_SIZE);
+
+	free_sja1000dev(netdev);
+
+	return 0;
+}
+
+static struct isa_driver tscan1_isa_driver = {
+	.probe = tscan1_probe,
+	.remove = __devexit_p(tscan1_remove),
+	.driver = {
+		.name = "tscan1",
+	},
+};
+
+static int __init tscan1_init(void)
+{
+	return isa_register_driver(&tscan1_isa_driver, TSCAN1_MAXDEV);
+}
+module_init(tscan1_init);
+
+static void __exit tscan1_exit(void)
+{
+	isa_unregister_driver(&tscan1_isa_driver);
+}
+module_exit(tscan1_exit);