| /* |
| * Driver for CC770 and AN82527 CAN controllers on the platform bus |
| * |
| * Copyright (C) 2009, 2011 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. |
| */ |
| |
| /* |
| * If platform data are used you should have similar definitions |
| * in your board-specific code: |
| * |
| * static struct cc770_platform_data myboard_cc770_pdata = { |
| * .osc_freq = 16000000, |
| * .cir = 0x41, |
| * .cor = 0x20, |
| * .bcr = 0x40, |
| * }; |
| * |
| * Please see include/linux/can/platform/cc770.h for description of |
| * above fields. |
| * |
| * If the device tree is used, you need a CAN node definition in your |
| * DTS file similar to: |
| * |
| * can@3,100 { |
| * compatible = "bosch,cc770"; |
| * reg = <3 0x100 0x80>; |
| * interrupts = <2 0>; |
| * interrupt-parent = <&mpic>; |
| * bosch,external-clock-frequency = <16000000>; |
| * }; |
| * |
| * See "Documentation/devicetree/bindings/net/can/cc770.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/platform_device.h> |
| #include <linux/of.h> |
| #include <linux/can.h> |
| #include <linux/can/dev.h> |
| #include <linux/can/platform/cc770.h> |
| |
| #include "cc770.h" |
| |
| #define DRV_NAME "cc770_platform" |
| |
| MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); |
| MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the platform bus"); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_ALIAS("platform:" DRV_NAME); |
| |
| #define CC770_PLATFORM_CAN_CLOCK 16000000 |
| |
| static u8 cc770_platform_read_reg(const struct cc770_priv *priv, int reg) |
| { |
| return ioread8(priv->reg_base + reg); |
| } |
| |
| static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg, |
| u8 val) |
| { |
| iowrite8(val, priv->reg_base + reg); |
| } |
| |
| static int cc770_get_of_node_data(struct platform_device *pdev, |
| struct cc770_priv *priv) |
| { |
| struct device_node *np = pdev->dev.of_node; |
| const u32 *prop; |
| int prop_size; |
| u32 clkext; |
| |
| prop = of_get_property(np, "bosch,external-clock-frequency", |
| &prop_size); |
| if (prop && (prop_size == sizeof(u32))) |
| clkext = *prop; |
| else |
| clkext = CC770_PLATFORM_CAN_CLOCK; /* default */ |
| priv->can.clock.freq = clkext; |
| |
| /* The system clock may not exceed 10 MHz */ |
| if (priv->can.clock.freq > 10000000) { |
| priv->cpu_interface |= CPUIF_DSC; |
| priv->can.clock.freq /= 2; |
| } |
| |
| /* The memory clock may not exceed 8 MHz */ |
| if (priv->can.clock.freq > 8000000) |
| priv->cpu_interface |= CPUIF_DMC; |
| |
| if (of_get_property(np, "bosch,divide-memory-clock", NULL)) |
| priv->cpu_interface |= CPUIF_DMC; |
| if (of_get_property(np, "bosch,iso-low-speed-mux", NULL)) |
| priv->cpu_interface |= CPUIF_MUX; |
| |
| if (!of_get_property(np, "bosch,no-comperator-bypass", NULL)) |
| priv->bus_config |= BUSCFG_CBY; |
| if (of_get_property(np, "bosch,disconnect-rx0-input", NULL)) |
| priv->bus_config |= BUSCFG_DR0; |
| if (of_get_property(np, "bosch,disconnect-rx1-input", NULL)) |
| priv->bus_config |= BUSCFG_DR1; |
| if (of_get_property(np, "bosch,disconnect-tx1-output", NULL)) |
| priv->bus_config |= BUSCFG_DT1; |
| if (of_get_property(np, "bosch,polarity-dominant", NULL)) |
| priv->bus_config |= BUSCFG_POL; |
| |
| prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size); |
| if (prop && (prop_size == sizeof(u32)) && *prop > 0) { |
| u32 cdv = clkext / *prop; |
| int slew; |
| |
| if (cdv > 0 && cdv < 16) { |
| priv->cpu_interface |= CPUIF_CEN; |
| priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK; |
| |
| prop = of_get_property(np, "bosch,slew-rate", |
| &prop_size); |
| if (prop && (prop_size == sizeof(u32))) { |
| slew = *prop; |
| } else { |
| /* Determine default slew rate */ |
| slew = (CLKOUT_SL_MASK >> |
| CLKOUT_SL_SHIFT) - |
| ((cdv * clkext - 1) / 8000000); |
| if (slew < 0) |
| slew = 0; |
| } |
| priv->clkout |= (slew << CLKOUT_SL_SHIFT) & |
| CLKOUT_SL_MASK; |
| } else { |
| dev_dbg(&pdev->dev, "invalid clock-out-frequency\n"); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int cc770_get_platform_data(struct platform_device *pdev, |
| struct cc770_priv *priv) |
| { |
| |
| struct cc770_platform_data *pdata = dev_get_platdata(&pdev->dev); |
| |
| priv->can.clock.freq = pdata->osc_freq; |
| if (priv->cpu_interface & CPUIF_DSC) |
| priv->can.clock.freq /= 2; |
| priv->clkout = pdata->cor; |
| priv->bus_config = pdata->bcr; |
| priv->cpu_interface = pdata->cir; |
| |
| return 0; |
| } |
| |
| static int cc770_platform_probe(struct platform_device *pdev) |
| { |
| struct net_device *dev; |
| struct cc770_priv *priv; |
| struct resource *mem; |
| resource_size_t mem_size; |
| void __iomem *base; |
| int err, irq; |
| |
| mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| irq = platform_get_irq(pdev, 0); |
| if (!mem || irq <= 0) |
| return -ENODEV; |
| |
| mem_size = resource_size(mem); |
| if (!request_mem_region(mem->start, mem_size, pdev->name)) |
| return -EBUSY; |
| |
| base = ioremap(mem->start, mem_size); |
| if (!base) { |
| err = -ENOMEM; |
| goto exit_release_mem; |
| } |
| |
| dev = alloc_cc770dev(0); |
| if (!dev) { |
| err = -ENOMEM; |
| goto exit_unmap_mem; |
| } |
| |
| dev->irq = irq; |
| priv = netdev_priv(dev); |
| priv->read_reg = cc770_platform_read_reg; |
| priv->write_reg = cc770_platform_write_reg; |
| priv->irq_flags = IRQF_SHARED; |
| priv->reg_base = base; |
| |
| if (pdev->dev.of_node) |
| err = cc770_get_of_node_data(pdev, priv); |
| else if (dev_get_platdata(&pdev->dev)) |
| err = cc770_get_platform_data(pdev, priv); |
| else |
| err = -ENODEV; |
| if (err) |
| goto exit_free_cc770; |
| |
| dev_dbg(&pdev->dev, |
| "reg_base=0x%p irq=%d clock=%d cpu_interface=0x%02x " |
| "bus_config=0x%02x clkout=0x%02x\n", |
| priv->reg_base, dev->irq, priv->can.clock.freq, |
| priv->cpu_interface, priv->bus_config, priv->clkout); |
| |
| platform_set_drvdata(pdev, dev); |
| SET_NETDEV_DEV(dev, &pdev->dev); |
| |
| err = register_cc770dev(dev); |
| if (err) { |
| dev_err(&pdev->dev, |
| "couldn't register CC700 device (err=%d)\n", err); |
| goto exit_free_cc770; |
| } |
| |
| return 0; |
| |
| exit_free_cc770: |
| free_cc770dev(dev); |
| exit_unmap_mem: |
| iounmap(base); |
| exit_release_mem: |
| release_mem_region(mem->start, mem_size); |
| |
| return err; |
| } |
| |
| static int cc770_platform_remove(struct platform_device *pdev) |
| { |
| struct net_device *dev = platform_get_drvdata(pdev); |
| struct cc770_priv *priv = netdev_priv(dev); |
| struct resource *mem; |
| |
| unregister_cc770dev(dev); |
| iounmap(priv->reg_base); |
| free_cc770dev(dev); |
| |
| mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| release_mem_region(mem->start, resource_size(mem)); |
| |
| return 0; |
| } |
| |
| static struct of_device_id cc770_platform_table[] = { |
| {.compatible = "bosch,cc770"}, /* CC770 from Bosch */ |
| {.compatible = "intc,82527"}, /* AN82527 from Intel CP */ |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, cc770_platform_table); |
| |
| static struct platform_driver cc770_platform_driver = { |
| .driver = { |
| .name = DRV_NAME, |
| .of_match_table = cc770_platform_table, |
| }, |
| .probe = cc770_platform_probe, |
| .remove = cc770_platform_remove, |
| }; |
| |
| module_platform_driver(cc770_platform_driver); |