can/sja1000/sja1000_platform.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (C) 2005 Sascha Hauer, Pengutronix
0004  * Copyright (C) 2007 Wolfgang Grandegger <wg@grandegger.com>
0005  */
0006
0007 #include <linux/kernel.h>
0008 #include <linux/module.h>
0009 #include <linux/interrupt.h>
0010 #include <linux/netdevice.h>
0011 #include <linux/delay.h>
0012 #include <linux/pci.h>
0013 #include <linux/platform_device.h>
0014 #include <linux/irq.h>
0015 #include <linux/can/dev.h>
0016 #include <linux/can/platform/sja1000.h>
0017 #include <linux/io.h>
0018 #include <linux/of.h>
0019 #include <linux/of_device.h>
0020
0021 #include "sja1000.h"
0022
0023 #define DRV_NAME "sja1000_platform"
0024 #define SP_CAN_CLOCK  (16000000 / 2)
0025
0026 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
0027 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
0028 MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
0029 MODULE_ALIAS("platform:" DRV_NAME);
0030 MODULE_LICENSE("GPL v2");
0031
0032 struct sja1000_of_data {
0033     size_t  priv_sz;
0034     void    (*init)(struct sja1000_priv *priv, struct device_node *of);
0035 };
0036
0037 struct technologic_priv {
0038     spinlock_t      io_lock;
0039 };
0040
0041 static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
0042 {
0043     return ioread8(priv->reg_base + reg);
0044 }
0045
0046 static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
0047 {
0048     iowrite8(val, priv->reg_base + reg);
0049 }
0050
0051 static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
0052 {
0053     return ioread8(priv->reg_base + reg * 2);
0054 }
0055
0056 static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
0057 {
0058     iowrite8(val, priv->reg_base + reg * 2);
0059 }
0060
0061 static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
0062 {
0063     return ioread8(priv->reg_base + reg * 4);
0064 }
0065
0066 static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
0067 {
0068     iowrite8(val, priv->reg_base + reg * 4);
0069 }
0070
0071 static u8 sp_technologic_read_reg16(const struct sja1000_priv *priv, int reg)
0072 {
0073     struct technologic_priv *tp = priv->priv;
0074     unsigned long flags;
0075     u8 val;
0076
0077     spin_lock_irqsave(&tp->io_lock, flags);
0078     iowrite16(reg, priv->reg_base + 0);
0079     val = ioread16(priv->reg_base + 2);
0080     spin_unlock_irqrestore(&tp->io_lock, flags);
0081
0082     return val;
0083 }
0084
0085 static void sp_technologic_write_reg16(const struct sja1000_priv *priv,
0086                        int reg, u8 val)
0087 {
0088     struct technologic_priv *tp = priv->priv;
0089     unsigned long flags;
0090
0091     spin_lock_irqsave(&tp->io_lock, flags);
0092     iowrite16(reg, priv->reg_base + 0);
0093     iowrite16(val, priv->reg_base + 2);
0094     spin_unlock_irqrestore(&tp->io_lock, flags);
0095 }
0096
0097 static void sp_technologic_init(struct sja1000_priv *priv, struct device_node *of)
0098 {
0099     struct technologic_priv *tp = priv->priv;
0100
0101     priv->read_reg = sp_technologic_read_reg16;
0102     priv->write_reg = sp_technologic_write_reg16;
0103     spin_lock_init(&tp->io_lock);
0104 }
0105
0106 static void sp_populate(struct sja1000_priv *priv,
0107             struct sja1000_platform_data *pdata,
0108             unsigned long resource_mem_flags)
0109 {
0110     /* The CAN clock frequency is half the oscillator clock frequency */
0111     priv->can.clock.freq = pdata->osc_freq / 2;
0112     priv->ocr = pdata->ocr;
0113     priv->cdr = pdata->cdr;
0114
0115     switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
0116     case IORESOURCE_MEM_32BIT:
0117         priv->read_reg = sp_read_reg32;
0118         priv->write_reg = sp_write_reg32;
0119         break;
0120     case IORESOURCE_MEM_16BIT:
0121         priv->read_reg = sp_read_reg16;
0122         priv->write_reg = sp_write_reg16;
0123         break;
0124     case IORESOURCE_MEM_8BIT:
0125     default:
0126         priv->read_reg = sp_read_reg8;
0127         priv->write_reg = sp_write_reg8;
0128         break;
0129     }
0130 }
0131
0132 static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
0133 {
0134     int err;
0135     u32 prop;
0136
0137     err = of_property_read_u32(of, "reg-io-width", &prop);
0138     if (err)
0139         prop = 1; /* 8 bit is default */
0140
0141     switch (prop) {
0142     case 4:
0143         priv->read_reg = sp_read_reg32;
0144         priv->write_reg = sp_write_reg32;
0145         break;
0146     case 2:
0147         priv->read_reg = sp_read_reg16;
0148         priv->write_reg = sp_write_reg16;
0149         break;
0150     case 1:
0151     default:
0152         priv->read_reg = sp_read_reg8;
0153         priv->write_reg = sp_write_reg8;
0154     }
0155
0156     err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
0157     if (!err)
0158         priv->can.clock.freq = prop / 2;
0159     else
0160         priv->can.clock.freq = SP_CAN_CLOCK; /* default */
0161
0162     err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
0163     if (!err)
0164         priv->ocr |= prop & OCR_MODE_MASK;
0165     else
0166         priv->ocr |= OCR_MODE_NORMAL; /* default */
0167
0168     err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
0169     if (!err)
0170         priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
0171     else
0172         priv->ocr |= OCR_TX0_PULLDOWN; /* default */
0173
0174     err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
0175     if (!err && prop) {
0176         u32 divider = priv->can.clock.freq * 2 / prop;
0177
0178         if (divider > 1)
0179             priv->cdr |= divider / 2 - 1;
0180         else
0181             priv->cdr |= CDR_CLKOUT_MASK;
0182     } else {
0183         priv->cdr |= CDR_CLK_OFF; /* default */
0184     }
0185
0186     if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
0187         priv->cdr |= CDR_CBP; /* default */
0188 }
0189
0190 static struct sja1000_of_data technologic_data = {
0191     .priv_sz = sizeof(struct technologic_priv),
0192     .init = sp_technologic_init,
0193 };
0194
0195 static const struct of_device_id sp_of_table[] = {
0196     { .compatible = "nxp,sja1000", .data = NULL, },
0197     { .compatible = "technologic,sja1000", .data = &technologic_data, },
0198     { /* sentinel */ },
0199 };
0200 MODULE_DEVICE_TABLE(of, sp_of_table);
0201
0202 static int sp_probe(struct platform_device *pdev)
0203 {
0204     int err, irq = 0;
0205     void __iomem *addr;
0206     struct net_device *dev;
0207     struct sja1000_priv *priv;
0208     struct resource *res_mem, *res_irq = NULL;
0209     struct sja1000_platform_data *pdata;
0210     struct device_node *of = pdev->dev.of_node;
0211     const struct sja1000_of_data *of_data = NULL;
0212     size_t priv_sz = 0;
0213
0214     pdata = dev_get_platdata(&pdev->dev);
0215     if (!pdata && !of) {
0216         dev_err(&pdev->dev, "No platform data provided!\n");
0217         return -ENODEV;
0218     }
0219
0220     res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
0221     if (!res_mem)
0222         return -ENODEV;
0223
0224     if (!devm_request_mem_region(&pdev->dev, res_mem->start,
0225                      resource_size(res_mem), DRV_NAME))
0226         return -EBUSY;
0227
0228     addr = devm_ioremap(&pdev->dev, res_mem->start,
0229                     resource_size(res_mem));
0230     if (!addr)
0231         return -ENOMEM;
0232
0233     if (of) {
0234         irq = platform_get_irq(pdev, 0);
0235         if (irq < 0)
0236             return irq;
0237     } else {
0238         res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
0239         if (!res_irq)
0240             return -ENODEV;
0241     }
0242
0243     of_data = device_get_match_data(&pdev->dev);
0244     if (of_data)
0245         priv_sz = of_data->priv_sz;
0246
0247     dev = alloc_sja1000dev(priv_sz);
0248     if (!dev)
0249         return -ENOMEM;
0250     priv = netdev_priv(dev);
0251
0252     if (res_irq) {
0253         irq = res_irq->start;
0254         priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
0255         if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
0256             priv->irq_flags |= IRQF_SHARED;
0257     } else {
0258         priv->irq_flags = IRQF_SHARED;
0259     }
0260
0261     dev->irq = irq;
0262     priv->reg_base = addr;
0263
0264     if (of) {
0265         sp_populate_of(priv, of);
0266
0267         if (of_data && of_data->init)
0268             of_data->init(priv, of);
0269     } else {
0270         sp_populate(priv, pdata, res_mem->flags);
0271     }
0272
0273     platform_set_drvdata(pdev, dev);
0274     SET_NETDEV_DEV(dev, &pdev->dev);
0275
0276     err = register_sja1000dev(dev);
0277     if (err) {
0278         dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
0279             DRV_NAME, err);
0280         goto exit_free;
0281     }
0282
0283     dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
0284          DRV_NAME, priv->reg_base, dev->irq);
0285     return 0;
0286
0287  exit_free:
0288     free_sja1000dev(dev);
0289     return err;
0290 }
0291
0292 static int sp_remove(struct platform_device *pdev)
0293 {
0294     struct net_device *dev = platform_get_drvdata(pdev);
0295
0296     unregister_sja1000dev(dev);
0297     free_sja1000dev(dev);
0298
0299     return 0;
0300 }
0301
0302 static struct platform_driver sp_driver = {
0303     .probe = sp_probe,
0304     .remove = sp_remove,
0305     .driver = {
0306         .name = DRV_NAME,
0307         .of_match_table = sp_of_table,
0308     },
0309 };
0310
0311 module_platform_driver(sp_driver);