From 5b92da0443c2585e31b64e86c2e1b8e22845d4bb Mon Sep 17 00:00:00 2001 From: Federico Vaga Date: Thu, 14 Jun 2012 13:43:42 +0200 Subject: [PATCH] c_can_pci: generic module for C_CAN/D_CAN on PCI Signed-off-by: Federico Vaga Acked-by: Giancarlo Asnaghi Cc: Alan Cox Acked-by: Wolfgang Grandegger Acked-by: Bhupesh Sharma [mkl: fix call to pci_iounmap] Signed-off-by: Marc Kleine-Budde --- drivers/net/can/c_can/Kconfig | 7 + drivers/net/can/c_can/Makefile | 1 + drivers/net/can/c_can/c_can_pci.c | 236 ++++++++++++++++++++++++++++++ 3 files changed, 244 insertions(+) create mode 100644 drivers/net/can/c_can/c_can_pci.c diff --git a/drivers/net/can/c_can/Kconfig b/drivers/net/can/c_can/Kconfig index 25d371cf98dd..3b83bafcd947 100644 --- a/drivers/net/can/c_can/Kconfig +++ b/drivers/net/can/c_can/Kconfig @@ -13,4 +13,11 @@ config CAN_C_CAN_PLATFORM boards from ST Microelectronics (http://www.st.com) like the SPEAr1310 and SPEAr320 evaluation boards & TI (www.ti.com) boards like am335x, dm814x, dm813x and dm811x. + +config CAN_C_CAN_PCI + tristate "Generic PCI Bus based C_CAN/D_CAN driver" + depends on PCI + ---help--- + This driver adds support for the C_CAN/D_CAN chips connected + to the PCI bus. endif diff --git a/drivers/net/can/c_can/Makefile b/drivers/net/can/c_can/Makefile index 9273f6d5c4b7..ad1cc842170a 100644 --- a/drivers/net/can/c_can/Makefile +++ b/drivers/net/can/c_can/Makefile @@ -4,5 +4,6 @@ obj-$(CONFIG_CAN_C_CAN) += c_can.o obj-$(CONFIG_CAN_C_CAN_PLATFORM) += c_can_platform.o +obj-$(CONFIG_CAN_C_CAN_PCI) += c_can_pci.o ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG 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 000000000000..914aecfa09a9 --- /dev/null +++ b/drivers/net/can/c_can/c_can_pci.c @@ -0,0 +1,236 @@ +/* + * PCI bus driver for Bosch C_CAN/D_CAN controller + * + * Copyright (C) 2012 Federico Vaga + * + * 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 +#include +#include +#include +#include + +#include + +#include "c_can.h" + +enum c_can_pci_reg_align { + C_CAN_REG_ALIGN_16, + C_CAN_REG_ALIGN_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 if clk is not usable */ + unsigned int freq; +}; + +/* + * 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(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(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(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(struct c_can_priv *priv, + enum reg index, u16 val) +{ + writew(val, priv->base + 2 * priv->regs[index]); +} + +static int __devinit 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; + struct clk *clk; + 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; + } + + pci_set_master(pdev); + pci_enable_msi(pdev); + + addr = pci_iomap(pdev, 0, pci_resource_len(pdev, 0)); + 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; + + if (!c_can_pci_data->freq) { + /* get the appropriate clk */ + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "no clock defined\n"); + ret = -ENODEV; + goto out_free_c_can; + } + priv->can.clock.freq = clk_get_rate(clk); + priv->priv = clk; + } else { + priv->can.clock.freq = c_can_pci_data->freq; + priv->priv = NULL; + } + + /* Configure CAN type */ + switch (c_can_pci_data->type) { + case C_CAN_DEVTYPE: + priv->regs = reg_map_c_can; + break; + case D_CAN_DEVTYPE: + priv->regs = reg_map_d_can; + priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; + break; + default: + ret = -EINVAL; + goto out_free_clock; + } + + /* 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; + default: + ret = -EINVAL; + goto out_free_clock; + } + + ret = register_c_can_dev(dev); + if (ret) { + dev_err(&pdev->dev, "registering %s failed (err=%d)\n", + KBUILD_MODNAME, ret); + goto out_free_clock; + } + + dev_dbg(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n", + KBUILD_MODNAME, priv->regs, dev->irq); + + return 0; + +out_free_clock: + if (priv->priv) + clk_put(priv->priv); +out_free_c_can: + pci_set_drvdata(pdev, NULL); + 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 __devexit c_can_pci_remove(struct pci_dev *pdev) +{ + struct net_device *dev = pci_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(dev); + + unregister_c_can_dev(dev); + + if (priv->priv) + clk_put(priv->priv); + + pci_set_drvdata(pdev, NULL); + free_c_can_dev(dev); + + pci_iounmap(pdev, priv->base); + pci_disable_msi(pdev); + pci_clear_master(pdev); + pci_release_regions(pdev); + pci_disable_device(pdev); +} + +static struct c_can_pci_data c_can_sta2x11= { + .type = C_CAN_DEVTYPE, + .reg_align = C_CAN_REG_ALIGN_32, + .freq = 52000000, /* 52 Mhz */ +}; + +#define C_CAN_ID(_vend, _dev, _driverdata) { \ + PCI_DEVICE(_vend, _dev), \ + .driver_data = (unsigned long)&_driverdata, \ +} +static DEFINE_PCI_DEVICE_TABLE(c_can_pci_tbl) = { + C_CAN_ID(PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_CAN, + c_can_sta2x11), + {}, +}; +static struct pci_driver c_can_pci_driver = { + .name = KBUILD_MODNAME, + .id_table = c_can_pci_tbl, + .probe = c_can_pci_probe, + .remove = __devexit_p(c_can_pci_remove), +}; + +module_pci_driver(c_can_pci_driver); + +MODULE_AUTHOR("Federico Vaga "); +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); -- 2.39.5