net/can: add driver for mscan family & mpc52xx_mscan
Taken from socketcan-svn, fixed remaining todos, cleaned up, tested with a
phyCORE-MPC5200B-IO and a custom board.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/mscan/mpc52xx_can.c b/drivers/net/can/mscan/mpc52xx_can.c
new file mode 100644
index 0000000..4707a82
--- /dev/null
+++ b/drivers/net/can/mscan/mpc52xx_can.c
@@ -0,0 +1,279 @@
+/*
+ * CAN bus driver for the Freescale MPC5xxx embedded CPU.
+ *
+ * Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>,
+ * Varma Electronics Oy
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ * Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
+ *
+ * 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
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/netdevice.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/of_platform.h>
+#include <sysdev/fsl_soc.h>
+#include <linux/io.h>
+#include <asm/mpc52xx.h>
+
+#include "mscan.h"
+
+
+#define DRV_NAME "mpc5xxx_can"
+
+static struct of_device_id mpc52xx_cdm_ids[] __devinitdata = {
+ { .compatible = "fsl,mpc5200-cdm", },
+ { .compatible = "fsl,mpc5200b-cdm", },
+ {}
+};
+
+/*
+ * Get the frequency of the external oscillator clock connected
+ * to the SYS_XTAL_IN pin, or return 0 if it cannot be determined.
+ */
+static unsigned int __devinit mpc52xx_can_xtal_freq(struct of_device *of)
+{
+ struct mpc52xx_cdm __iomem *cdm;
+ struct device_node *np_cdm;
+ unsigned int freq;
+ u32 val;
+
+ freq = mpc5xxx_get_bus_frequency(of->node);
+ if (!freq)
+ return 0;
+
+ /*
+ * Determine SYS_XTAL_IN frequency from the clock domain settings
+ */
+ np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids);
+ if (!np_cdm) {
+ dev_err(&of->dev, "can't get clock node!\n");
+ return 0;
+ }
+ cdm = of_iomap(np_cdm, 0);
+ of_node_put(np_cdm);
+
+ if (in_8(&cdm->ipb_clk_sel) & 0x1)
+ freq *= 2;
+ val = in_be32(&cdm->rstcfg);
+ if (val & (1 << 5))
+ freq *= 8;
+ else
+ freq *= 4;
+ if (val & (1 << 6))
+ freq /= 12;
+ else
+ freq /= 16;
+
+ iounmap(cdm);
+
+ return freq;
+}
+
+/*
+ * Get frequency of the MSCAN clock source
+ *
+ * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock (IP_CLK)
+ * can be selected. According to the MPC5200 user's manual, the oscillator
+ * clock is the better choice as it has less jitter but due to a hardware
+ * bug, it can not be selected for the old MPC5200 Rev. A chips.
+ */
+
+static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of,
+ int clock_src)
+{
+ unsigned int pvr;
+
+ pvr = mfspr(SPRN_PVR);
+
+ if (clock_src == MSCAN_CLKSRC_BUS || pvr == 0x80822011)
+ return mpc5xxx_get_bus_frequency(of->node);
+
+ return mpc52xx_can_xtal_freq(of);
+}
+
+static int __devinit mpc5xxx_can_probe(struct of_device *ofdev,
+ const struct of_device_id *id)
+{
+ struct device_node *np = ofdev->node;
+ struct net_device *dev;
+ struct mscan_priv *priv;
+ void __iomem *base;
+ const char *clk_src;
+ int err, irq, clock_src;
+
+ base = of_iomap(ofdev->node, 0);
+ if (!base) {
+ dev_err(&ofdev->dev, "couldn't ioremap\n");
+ err = -ENOMEM;
+ goto exit_release_mem;
+ }
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq) {
+ dev_err(&ofdev->dev, "no irq found\n");
+ err = -ENODEV;
+ goto exit_unmap_mem;
+ }
+
+ dev = alloc_mscandev();
+ if (!dev) {
+ err = -ENOMEM;
+ goto exit_dispose_irq;
+ }
+
+ priv = netdev_priv(dev);
+ priv->reg_base = base;
+ dev->irq = irq;
+
+ /*
+ * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock
+ * (IP_CLK) can be selected as MSCAN clock source. According to
+ * the MPC5200 user's manual, the oscillator clock is the better
+ * choice as it has less jitter. For this reason, it is selected
+ * by default.
+ */
+ clk_src = of_get_property(np, "fsl,mscan-clk-src", NULL);
+ if (clk_src && strcmp(clk_src, "ip") == 0)
+ clock_src = MSCAN_CLKSRC_BUS;
+ else
+ clock_src = MSCAN_CLKSRC_XTAL;
+ priv->can.clock.freq = mpc52xx_can_clock_freq(ofdev, clock_src);
+ if (!priv->can.clock.freq) {
+ dev_err(&ofdev->dev, "couldn't get MSCAN clock frequency\n");
+ err = -ENODEV;
+ goto exit_free_mscan;
+ }
+
+ SET_NETDEV_DEV(dev, &ofdev->dev);
+
+ err = register_mscandev(dev, clock_src);
+ if (err) {
+ dev_err(&ofdev->dev, "registering %s failed (err=%d)\n",
+ DRV_NAME, err);
+ goto exit_free_mscan;
+ }
+
+ dev_set_drvdata(&ofdev->dev, dev);
+
+ dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n",
+ priv->reg_base, dev->irq, priv->can.clock.freq);
+
+ return 0;
+
+exit_free_mscan:
+ free_candev(dev);
+exit_dispose_irq:
+ irq_dispose_mapping(irq);
+exit_unmap_mem:
+ iounmap(base);
+exit_release_mem:
+ return err;
+}
+
+static int __devexit mpc5xxx_can_remove(struct of_device *ofdev)
+{
+ struct net_device *dev = dev_get_drvdata(&ofdev->dev);
+ struct mscan_priv *priv = netdev_priv(dev);
+
+ dev_set_drvdata(&ofdev->dev, NULL);
+
+ unregister_mscandev(dev);
+ iounmap(priv->reg_base);
+ irq_dispose_mapping(dev->irq);
+ free_candev(dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static struct mscan_regs saved_regs;
+static int mpc5xxx_can_suspend(struct of_device *ofdev, pm_message_t state)
+{
+ struct net_device *dev = dev_get_drvdata(&ofdev->dev);
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+
+ _memcpy_fromio(&saved_regs, regs, sizeof(*regs));
+
+ return 0;
+}
+
+static int mpc5xxx_can_resume(struct of_device *ofdev)
+{
+ struct net_device *dev = dev_get_drvdata(&ofdev->dev);
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+
+ regs->canctl0 |= MSCAN_INITRQ;
+ while ((regs->canctl1 & MSCAN_INITAK) == 0)
+ udelay(10);
+
+ regs->canctl1 = saved_regs.canctl1;
+ regs->canbtr0 = saved_regs.canbtr0;
+ regs->canbtr1 = saved_regs.canbtr1;
+ regs->canidac = saved_regs.canidac;
+
+ /* restore masks, buffers etc. */
+ _memcpy_toio(®s->canidar1_0, (void *)&saved_regs.canidar1_0,
+ sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0));
+
+ regs->canctl0 &= ~MSCAN_INITRQ;
+ regs->cantbsel = saved_regs.cantbsel;
+ regs->canrier = saved_regs.canrier;
+ regs->cantier = saved_regs.cantier;
+ regs->canctl0 = saved_regs.canctl0;
+
+ return 0;
+}
+#endif
+
+static struct of_device_id __devinitdata mpc5xxx_can_table[] = {
+ {.compatible = "fsl,mpc5200-mscan"},
+ {.compatible = "fsl,mpc5200b-mscan"},
+ {},
+};
+
+static struct of_platform_driver mpc5xxx_can_driver = {
+ .owner = THIS_MODULE,
+ .name = "mpc5xxx_can",
+ .probe = mpc5xxx_can_probe,
+ .remove = __devexit_p(mpc5xxx_can_remove),
+#ifdef CONFIG_PM
+ .suspend = mpc5xxx_can_suspend,
+ .resume = mpc5xxx_can_resume,
+#endif
+ .match_table = mpc5xxx_can_table,
+};
+
+static int __init mpc5xxx_can_init(void)
+{
+ return of_register_platform_driver(&mpc5xxx_can_driver);
+}
+module_init(mpc5xxx_can_init);
+
+static void __exit mpc5xxx_can_exit(void)
+{
+ return of_unregister_platform_driver(&mpc5xxx_can_driver);
+};
+module_exit(mpc5xxx_can_exit);
+
+MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
+MODULE_DESCRIPTION("Freescale MPC5200 CAN driver");
+MODULE_LICENSE("GPL v2");