--- /dev/null
+/*
+ * Copyright (C) 2005 Sascha Hauer, Pengutronix
+ * Copyright (C) 2007 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+#include <linux/can/dev.h>
+#include <linux/can/platform/sja1000.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+
+#include "sja1000.h"
+
+#define DRV_NAME "sja1000_platform"
+#define SP_CAN_CLOCK (16000000 / 2)
+
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
+MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
+MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_LICENSE("GPL v2");
+
+static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
+{
+ return ioread8(priv->reg_base + reg);
+}
+
+static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
+{
+ iowrite8(val, priv->reg_base + reg);
+}
+
+static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
+{
+ return ioread8(priv->reg_base + reg * 2);
+}
+
+static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
+{
+ iowrite8(val, priv->reg_base + reg * 2);
+}
+
+static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
+{
+ return ioread8(priv->reg_base + reg * 4);
+}
+
+static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
+{
+ iowrite8(val, priv->reg_base + reg * 4);
+}
+
+static void sp_populate(struct sja1000_priv *priv,
+ struct sja1000_platform_data *pdata,
+ unsigned long resource_mem_flags)
+{
+ /* The CAN clock frequency is half the oscillator clock frequency */
+ priv->can.clock.freq = pdata->osc_freq / 2;
+ priv->ocr = pdata->ocr;
+ priv->cdr = pdata->cdr;
+
+ switch (resource_mem_flags & IORESOURCE_MEM_TYPE_MASK) {
+ case IORESOURCE_MEM_32BIT:
+ priv->read_reg = sp_read_reg32;
+ priv->write_reg = sp_write_reg32;
+ break;
+ case IORESOURCE_MEM_16BIT:
+ priv->read_reg = sp_read_reg16;
+ priv->write_reg = sp_write_reg16;
+ break;
+ case IORESOURCE_MEM_8BIT:
+ default:
+ priv->read_reg = sp_read_reg8;
+ priv->write_reg = sp_write_reg8;
+ break;
+ }
+}
+
+static void sp_populate_of(struct sja1000_priv *priv, struct device_node *of)
+{
+ int err;
+ u32 prop;
+
+ err = of_property_read_u32(of, "reg-io-width", &prop);
+ if (err)
+ prop = 1; /* 8 bit is default */
+
+ switch (prop) {
+ case 4:
+ priv->read_reg = sp_read_reg32;
+ priv->write_reg = sp_write_reg32;
+ break;
+ case 2:
+ priv->read_reg = sp_read_reg16;
+ priv->write_reg = sp_write_reg16;
+ break;
+ case 1: /* fallthrough */
+ default:
+ priv->read_reg = sp_read_reg8;
+ priv->write_reg = sp_write_reg8;
+ }
+
+ err = of_property_read_u32(of, "nxp,external-clock-frequency", &prop);
+ if (!err)
+ priv->can.clock.freq = prop / 2;
+ else
+ priv->can.clock.freq = SP_CAN_CLOCK; /* default */
+
+ err = of_property_read_u32(of, "nxp,tx-output-mode", &prop);
+ if (!err)
+ priv->ocr |= prop & OCR_MODE_MASK;
+ else
+ priv->ocr |= OCR_MODE_NORMAL; /* default */
+
+ err = of_property_read_u32(of, "nxp,tx-output-config", &prop);
+ if (!err)
+ priv->ocr |= (prop << OCR_TX_SHIFT) & OCR_TX_MASK;
+ else
+ priv->ocr |= OCR_TX0_PULLDOWN; /* default */
+
+ err = of_property_read_u32(of, "nxp,clock-out-frequency", &prop);
+ if (!err && 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 */
+ }
+
+ if (!of_property_read_bool(of, "nxp,no-comparator-bypass"))
+ priv->cdr |= CDR_CBP; /* default */
+}
+
+static int sp_probe(struct platform_device *pdev)
+{
+ int err, irq = 0;
+ void __iomem *addr;
+ struct net_device *dev;
+ struct sja1000_priv *priv;
+ struct resource *res_mem, *res_irq = NULL;
+ struct sja1000_platform_data *pdata;
+ struct device_node *of = pdev->dev.of_node;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata && !of) {
+ dev_err(&pdev->dev, "No platform data provided!\n");
+ return -ENODEV;
+ }
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res_mem)
+ return -ENODEV;
+
+ if (!devm_request_mem_region(&pdev->dev, res_mem->start,
+ resource_size(res_mem), DRV_NAME))
+ return -EBUSY;
+
+ addr = devm_ioremap_nocache(&pdev->dev, res_mem->start,
+ resource_size(res_mem));
+ if (!addr)
+ return -ENOMEM;
+
+ if (of)
+ irq = irq_of_parse_and_map(of, 0);
+ else
+ res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+
+ if (!irq && !res_irq)
+ return -ENODEV;
+
+ dev = alloc_sja1000dev(0);
+ if (!dev)
+ return -ENOMEM;
+ priv = netdev_priv(dev);
+
+ if (res_irq) {
+ irq = res_irq->start;
+ priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
+ if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
+ priv->irq_flags |= IRQF_SHARED;
+ } else {
+ priv->irq_flags = IRQF_SHARED;
+ }
+
+ dev->irq = irq;
+ priv->reg_base = addr;
+
+ if (of)
+ sp_populate_of(priv, of);
+ else
+ sp_populate(priv, pdata, res_mem->flags);
+
+ platform_set_drvdata(pdev, dev);
+ SET_NETDEV_DEV(dev, &pdev->dev);
+
+ err = register_sja1000dev(dev);
+ if (err) {
+ dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
+ DRV_NAME, err);
+ goto exit_free;
+ }
+
+ dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
+ DRV_NAME, priv->reg_base, dev->irq);
+ return 0;
+
+ exit_free:
+ free_sja1000dev(dev);
+ return err;
+}
+
+static int sp_remove(struct platform_device *pdev)
+{
+ struct net_device *dev = platform_get_drvdata(pdev);
+
+ unregister_sja1000dev(dev);
+ free_sja1000dev(dev);
+
+ return 0;
+}
+
+static const struct of_device_id sp_of_table[] = {
+ {.compatible = "nxp,sja1000"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, sp_of_table);
+
+static struct platform_driver sp_driver = {
+ .probe = sp_probe,
+ .remove = sp_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = sp_of_table,
+ },
+};
+
+module_platform_driver(sp_driver);
Code Review / kvmfornfv.git / blobdiff