+/*
+ * Driver for SJA1000 CAN controllers on the OpenFirmware platform bus
+ *
+ * Copyright (C) 2008-2009 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.
+ */
+
+/* This is a generic driver for SJA1000 chips on the OpenFirmware platform
+ * bus found on embedded PowerPC systems. You need a SJA1000 CAN node
+ * definition in your flattened device tree source (DTS) file similar to:
+ *
+ * can@3,100 {
+ * compatible = "nxp,sja1000";
+ * reg = <3 0x100 0x80>;
+ * interrupts = <2 0>;
+ * interrupt-parent = <&mpic>;
+ * nxp,external-clock-frequency = <16000000>;
+ * };
+ *
+ * See "Documentation/powerpc/dts-bindings/can/sja1000.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/can.h>
+#include <linux/can/dev.h>
+
+#include <linux/of_platform.h>
+#include <asm/prom.h>
+
+#include "sja1000.h"
+
+#define DRV_NAME "sja1000_of_platform"
+
+MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
+MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the OF platform bus");
+MODULE_LICENSE("GPL v2");
+
+#define SJA1000_OFP_CAN_CLOCK (16000000 / 2)
+
+#define SJA1000_OFP_OCR OCR_TX0_PULLDOWN
+#define SJA1000_OFP_CDR (CDR_CBP | CDR_CLK_OFF)
+
+static u8 sja1000_ofp_read_reg(const struct sja1000_priv *priv, int reg)
+{
+ return in_8(priv->reg_base + reg);
+}
+
+static void sja1000_ofp_write_reg(const struct sja1000_priv *priv,
+ int reg, u8 val)
+{
+ out_8(priv->reg_base + reg, val);
+}
+
+static int __devexit sja1000_ofp_remove(struct of_device *ofdev)
+{
+ struct net_device *dev = dev_get_drvdata(&ofdev->dev);
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct device_node *np = ofdev->node;
+ struct resource res;
+
+ dev_set_drvdata(&ofdev->dev, NULL);
+
+ unregister_sja1000dev(dev);
+ free_sja1000dev(dev);
+ iounmap(priv->reg_base);
+ irq_dispose_mapping(dev->irq);
+
+ of_address_to_resource(np, 0, &res);
+ release_mem_region(res.start, resource_size(&res));
+
+ return 0;
+}
+
+static int __devinit sja1000_ofp_probe(struct of_device *ofdev,
+ const struct of_device_id *id)
+{
+ struct device_node *np = ofdev->node;
+ struct net_device *dev;
+ struct sja1000_priv *priv;
+ struct resource res;
+ const u32 *prop;
+ int err, irq, res_size, prop_size;
+ void __iomem *base;
+
+ err = of_address_to_resource(np, 0, &res);
+ if (err) {
+ dev_err(&ofdev->dev, "invalid address\n");
+ return err;
+ }
+
+ res_size = resource_size(&res);
+
+ if (!request_mem_region(res.start, res_size, DRV_NAME)) {
+ dev_err(&ofdev->dev, "couldn't request %#x..%#x\n",
+ res.start, res.end);
+ return -EBUSY;
+ }
+
+ base = ioremap_nocache(res.start, res_size);
+ if (!base) {
+ dev_err(&ofdev->dev, "couldn't ioremap %#x..%#x\n",
+ res.start, res.end);
+ err = -ENOMEM;
+ goto exit_release_mem;
+ }
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq == NO_IRQ) {
+ dev_err(&ofdev->dev, "no irq found\n");
+ err = -ENODEV;
+ goto exit_unmap_mem;
+ }
+
+ dev = alloc_sja1000dev(0);
+ if (!dev) {
+ err = -ENOMEM;
+ goto exit_dispose_irq;
+ }
+
+ priv = netdev_priv(dev);
+
+ priv->read_reg = sja1000_ofp_read_reg;
+ priv->write_reg = sja1000_ofp_write_reg;
+
+ prop = of_get_property(np, "nxp,external-clock-frequency", &prop_size);
+ if (prop && (prop_size == sizeof(u32)))
+ priv->can.clock.freq = *prop / 2;
+ else
+ priv->can.clock.freq = SJA1000_OFP_CAN_CLOCK; /* default */
+
+ prop = of_get_property(np, "nxp,tx-output-mode", &prop_size);
+ if (prop && (prop_size == sizeof(u32)))
+ priv->ocr |= *prop & OCR_MODE_MASK;
+ else
+ priv->ocr |= OCR_MODE_NORMAL; /* default */
+
+ prop = of_get_property(np, "nxp,tx-output-config", &prop_size);
+ if (prop && (prop_size == sizeof(u32)))
+ priv->ocr |= (*prop << OCR_TX_SHIFT) & OCR_TX_MASK;
+ else
+ priv->ocr |= OCR_TX0_PULLDOWN; /* default */
+
+ prop = of_get_property(np, "nxp,clock-out-frequency", &prop_size);
+ if (prop && (prop_size == sizeof(u32)) && *prop) {
+ u32 divider = priv->can.clock.freq * 2 / *prop;
+
+ if (divider > 1)
+ priv->cdr |= divider / 2 - 1;
+ else
+ priv->cdr |= CDR_CLKOUT_MASK;
+ } else {
+ priv->cdr |= CDR_CLK_OFF; /* default */
+ }
+
+ prop = of_get_property(np, "nxp,no-comparator-bypass", NULL);
+ if (!prop)
+ priv->cdr |= CDR_CBP; /* default */
+
+ priv->irq_flags = IRQF_SHARED;
+ priv->reg_base = base;
+
+ dev->irq = irq;
+
+ dev_info(&ofdev->dev,
+ "reg_base=0x%p irq=%d clock=%d ocr=0x%02x cdr=0x%02x\n",
+ priv->reg_base, dev->irq, priv->can.clock.freq,
+ priv->ocr, priv->cdr);
+
+ dev_set_drvdata(&ofdev->dev, dev);
+ SET_NETDEV_DEV(dev, &ofdev->dev);
+
+ err = register_sja1000dev(dev);
+ if (err) {
+ dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
+ DRV_NAME, err);
+ goto exit_free_sja1000;
+ }
+
+ return 0;
+
+exit_free_sja1000:
+ free_sja1000dev(dev);
+exit_dispose_irq:
+ irq_dispose_mapping(irq);
+exit_unmap_mem:
+ iounmap(base);
+exit_release_mem:
+ release_mem_region(res.start, res_size);
+
+ return err;
+}
+
+static struct of_device_id __devinitdata sja1000_ofp_table[] = {
+ {.compatible = "nxp,sja1000"},
+ {},
+};
+
+static struct of_platform_driver sja1000_ofp_driver = {
+ .owner = THIS_MODULE,
+ .name = DRV_NAME,
+ .probe = sja1000_ofp_probe,
+ .remove = __devexit_p(sja1000_ofp_remove),
+ .match_table = sja1000_ofp_table,
+};
+
+static int __init sja1000_ofp_init(void)
+{
+ return of_register_platform_driver(&sja1000_ofp_driver);
+}
+module_init(sja1000_ofp_init);
+
+static void __exit sja1000_ofp_exit(void)
+{
+ return of_unregister_platform_driver(&sja1000_ofp_driver);
+};
+module_exit(sja1000_ofp_exit);
git.openpandora.org / pandora-kernel.git / commitdiff