diff options
Diffstat (limited to 'drivers/net/can/c_can/c_can_pci.c')
-rw-r--r-- | drivers/net/can/c_can/c_can_pci.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/drivers/net/can/c_can/c_can_pci.c b/drivers/net/can/c_can/c_can_pci.c new file mode 100644 index 000000000..7efb60b50 --- /dev/null +++ b/drivers/net/can/c_can/c_can_pci.c @@ -0,0 +1,294 @@ +/* + * PCI bus driver for Bosch C_CAN/D_CAN controller + * + * Copyright (C) 2012 Federico Vaga <federico.vaga@gmail.com> + * + * Borrowed from c_can_platform.c + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/pci.h> + +#include <linux/can/dev.h> + +#include "c_can.h" + +#define PCI_DEVICE_ID_PCH_CAN 0x8818 +#define PCH_PCI_SOFT_RESET 0x01fc + +enum c_can_pci_reg_align { + C_CAN_REG_ALIGN_16, + C_CAN_REG_ALIGN_32, + C_CAN_REG_32, +}; + +struct c_can_pci_data { + /* Specify if is C_CAN or D_CAN */ + enum c_can_dev_id type; + /* Set the register alignment in the memory */ + enum c_can_pci_reg_align reg_align; + /* Set the frequency */ + unsigned int freq; + /* PCI bar number */ + int bar; + /* Callback for reset */ + void (*init)(const struct c_can_priv *priv, bool enable); +}; + +/* + * 16-bit c_can registers can be arranged differently in the memory + * architecture of different implementations. For example: 16-bit + * registers can be aligned to a 16-bit boundary or 32-bit boundary etc. + * Handle the same by providing a common read/write interface. + */ +static u16 c_can_pci_read_reg_aligned_to_16bit(const struct c_can_priv *priv, + enum reg index) +{ + return readw(priv->base + priv->regs[index]); +} + +static void c_can_pci_write_reg_aligned_to_16bit(const struct c_can_priv *priv, + enum reg index, u16 val) +{ + writew(val, priv->base + priv->regs[index]); +} + +static u16 c_can_pci_read_reg_aligned_to_32bit(const struct c_can_priv *priv, + enum reg index) +{ + return readw(priv->base + 2 * priv->regs[index]); +} + +static void c_can_pci_write_reg_aligned_to_32bit(const struct c_can_priv *priv, + enum reg index, u16 val) +{ + writew(val, priv->base + 2 * priv->regs[index]); +} + +static u16 c_can_pci_read_reg_32bit(const struct c_can_priv *priv, + enum reg index) +{ + return (u16)ioread32(priv->base + 2 * priv->regs[index]); +} + +static void c_can_pci_write_reg_32bit(const struct c_can_priv *priv, + enum reg index, u16 val) +{ + iowrite32((u32)val, priv->base + 2 * priv->regs[index]); +} + +static u32 c_can_pci_read_reg32(const struct c_can_priv *priv, enum reg index) +{ + u32 val; + + val = priv->read_reg(priv, index); + val |= ((u32) priv->read_reg(priv, index + 1)) << 16; + + return val; +} + +static void c_can_pci_write_reg32(const struct c_can_priv *priv, enum reg index, + u32 val) +{ + priv->write_reg(priv, index + 1, val >> 16); + priv->write_reg(priv, index, val); +} + +static void c_can_pci_reset_pch(const struct c_can_priv *priv, bool enable) +{ + if (enable) { + u32 __iomem *addr = priv->base + PCH_PCI_SOFT_RESET; + + /* write to sw reset register */ + iowrite32(1, addr); + iowrite32(0, addr); + } +} + +static int c_can_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct c_can_pci_data *c_can_pci_data = (void *)ent->driver_data; + struct c_can_priv *priv; + struct net_device *dev; + void __iomem *addr; + int ret; + + ret = pci_enable_device(pdev); + if (ret) { + dev_err(&pdev->dev, "pci_enable_device FAILED\n"); + goto out; + } + + ret = pci_request_regions(pdev, KBUILD_MODNAME); + if (ret) { + dev_err(&pdev->dev, "pci_request_regions FAILED\n"); + goto out_disable_device; + } + + ret = pci_enable_msi(pdev); + if (!ret) { + dev_info(&pdev->dev, "MSI enabled\n"); + pci_set_master(pdev); + } + + addr = pci_iomap(pdev, c_can_pci_data->bar, + pci_resource_len(pdev, c_can_pci_data->bar)); + if (!addr) { + dev_err(&pdev->dev, + "device has no PCI memory resources, " + "failing adapter\n"); + ret = -ENOMEM; + goto out_release_regions; + } + + /* allocate the c_can device */ + dev = alloc_c_can_dev(); + if (!dev) { + ret = -ENOMEM; + goto out_iounmap; + } + + priv = netdev_priv(dev); + pci_set_drvdata(pdev, dev); + SET_NETDEV_DEV(dev, &pdev->dev); + + dev->irq = pdev->irq; + priv->base = addr; + priv->device = &pdev->dev; + + if (!c_can_pci_data->freq) { + dev_err(&pdev->dev, "no clock frequency defined\n"); + ret = -ENODEV; + goto out_free_c_can; + } else { + priv->can.clock.freq = c_can_pci_data->freq; + } + + /* Configure CAN type */ + switch (c_can_pci_data->type) { + case BOSCH_C_CAN: + priv->regs = reg_map_c_can; + break; + case BOSCH_D_CAN: + priv->regs = reg_map_d_can; + break; + default: + ret = -EINVAL; + goto out_free_c_can; + } + + priv->type = c_can_pci_data->type; + + /* Configure access to registers */ + switch (c_can_pci_data->reg_align) { + case C_CAN_REG_ALIGN_32: + priv->read_reg = c_can_pci_read_reg_aligned_to_32bit; + priv->write_reg = c_can_pci_write_reg_aligned_to_32bit; + break; + case C_CAN_REG_ALIGN_16: + priv->read_reg = c_can_pci_read_reg_aligned_to_16bit; + priv->write_reg = c_can_pci_write_reg_aligned_to_16bit; + break; + case C_CAN_REG_32: + priv->read_reg = c_can_pci_read_reg_32bit; + priv->write_reg = c_can_pci_write_reg_32bit; + break; + default: + ret = -EINVAL; + goto out_free_c_can; + } + priv->read_reg32 = c_can_pci_read_reg32; + priv->write_reg32 = c_can_pci_write_reg32; + + priv->raminit = c_can_pci_data->init; + + ret = register_c_can_dev(dev); + if (ret) { + dev_err(&pdev->dev, "registering %s failed (err=%d)\n", + KBUILD_MODNAME, ret); + goto out_free_c_can; + } + + dev_dbg(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n", + KBUILD_MODNAME, priv->regs, dev->irq); + + return 0; + +out_free_c_can: + free_c_can_dev(dev); +out_iounmap: + pci_iounmap(pdev, addr); +out_release_regions: + pci_disable_msi(pdev); + pci_clear_master(pdev); + pci_release_regions(pdev); +out_disable_device: + pci_disable_device(pdev); +out: + return ret; +} + +static void c_can_pci_remove(struct pci_dev *pdev) +{ + struct net_device *dev = pci_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(dev); + void __iomem *addr = priv->base; + + unregister_c_can_dev(dev); + + free_c_can_dev(dev); + + pci_iounmap(pdev, addr); + pci_disable_msi(pdev); + pci_clear_master(pdev); + pci_release_regions(pdev); + pci_disable_device(pdev); +} + +static const struct c_can_pci_data c_can_sta2x11= { + .type = BOSCH_C_CAN, + .reg_align = C_CAN_REG_ALIGN_32, + .freq = 52000000, /* 52 Mhz */ + .bar = 0, +}; + +static const struct c_can_pci_data c_can_pch = { + .type = BOSCH_C_CAN, + .reg_align = C_CAN_REG_32, + .freq = 50000000, /* 50 MHz */ + .init = c_can_pci_reset_pch, + .bar = 1, +}; + +#define C_CAN_ID(_vend, _dev, _driverdata) { \ + PCI_DEVICE(_vend, _dev), \ + .driver_data = (unsigned long)&_driverdata, \ +} + +static const struct pci_device_id c_can_pci_tbl[] = { + C_CAN_ID(PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_CAN, + c_can_sta2x11), + C_CAN_ID(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_PCH_CAN, + c_can_pch), + {}, +}; +static struct pci_driver c_can_pci_driver = { + .name = KBUILD_MODNAME, + .id_table = c_can_pci_tbl, + .probe = c_can_pci_probe, + .remove = c_can_pci_remove, +}; + +module_pci_driver(c_can_pci_driver); + +MODULE_AUTHOR("Federico Vaga <federico.vaga@gmail.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("PCI CAN bus driver for Bosch C_CAN/D_CAN controller"); +MODULE_DEVICE_TABLE(pci, c_can_pci_tbl); |