/* * Driver for SJA1000 CAN controllers on the OpenFirmware platform bus * * Copyright (C) 2008-2009 Wolfgang Grandegger * * 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/devicetree/bindings/net/can/sja1000.txt" for further * information. */ #include #include #include #include #include #include #include #include #include #include #include #include "sja1000.h" #define DRV_NAME "sja1000_of_platform" MODULE_AUTHOR("Wolfgang Grandegger "); 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 ioread8(priv->reg_base + reg); } static void sja1000_ofp_write_reg(const struct sja1000_priv *priv, int reg, u8 val) { iowrite8(val, priv->reg_base + reg); } static int sja1000_ofp_remove(struct platform_device *ofdev) { struct net_device *dev = dev_get_drvdata(&ofdev->dev); struct sja1000_priv *priv = netdev_priv(dev); struct device_node *np = ofdev->dev.of_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 sja1000_ofp_probe(struct platform_device *ofdev) { struct device_node *np = ofdev->dev.of_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 %pR\n", &res); return -EBUSY; } base = ioremap_nocache(res.start, res_size); if (!base) { dev_err(&ofdev->dev, "couldn't ioremap %pR\n", &res); 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 sja1000_ofp_table[] = { {.compatible = "nxp,sja1000"}, {}, }; MODULE_DEVICE_TABLE(of, sja1000_ofp_table); static struct platform_driver sja1000_ofp_driver = { .driver = { .owner = THIS_MODULE, .name = DRV_NAME, .of_match_table = sja1000_ofp_table, }, .probe = sja1000_ofp_probe, .remove = sja1000_ofp_remove, }; module_platform_driver(sja1000_ofp_driver);