Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760628Ab2FDNbb (ORCPT ); Mon, 4 Jun 2012 09:31:31 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:53020 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753105Ab2FDNb0 (ORCPT ); Mon, 4 Jun 2012 09:31:26 -0400 From: Federico Vaga To: Wolfgang Grandegger , Marc Kleine-Budde Cc: Federico Vaga , Giancarlo Asnaghi , Alan Cox , Alessandro Rubini , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH RFC] c_can_pci: generic module for c_can on PCI Date: Mon, 4 Jun 2012 15:32:46 +0200 Message-Id: <1338816766-7089-2-git-send-email-federico.vaga@gmail.com> X-Mailer: git-send-email 1.7.10.2 In-Reply-To: <1338816766-7089-1-git-send-email-federico.vaga@gmail.com> References: <4FC135C6.5030206@grandegger.com> <1338816766-7089-1-git-send-email-federico.vaga@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7881 Lines: 283 Signed-off-by: Federico Vaga Acked-by: Giancarlo Asnaghi Cc: Alan Cox --- drivers/net/can/c_can/Kconfig | 11 +- drivers/net/can/c_can/Makefile | 1 + drivers/net/can/c_can/c_can_pci.c | 221 +++++++++++++++++++++++++++++++++++++ 3 files changed, 230 insertions(+), 3 deletions(-) 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 ffb9773..74ef97d 100644 --- a/drivers/net/can/c_can/Kconfig +++ b/drivers/net/can/c_can/Kconfig @@ -2,14 +2,19 @@ menuconfig CAN_C_CAN tristate "Bosch C_CAN devices" depends on CAN_DEV && HAS_IOMEM -if CAN_C_CAN - config CAN_C_CAN_PLATFORM tristate "Generic Platform Bus based C_CAN driver" + depends on CAN_C_CAN ---help--- This driver adds support for the C_CAN chips connected to the "platform bus" (Linux abstraction for directly to the processor attached devices) which can be found on various boards from ST Microelectronics (http://www.st.com) like the SPEAr1310 and SPEAr320 evaluation boards. -endif + +config CAN_C_CAN_PCI + tristate "Generic PCI Bus based C_CAN driver" + depends on CAN_C_CAN + ---help--- + This driver adds support for the C_CAN chips connected to + the PCI bus. diff --git a/drivers/net/can/c_can/Makefile b/drivers/net/can/c_can/Makefile index 9273f6d..ad1cc84 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 0000000..b635375 --- /dev/null +++ b/drivers/net/can/c_can/c_can_pci.c @@ -0,0 +1,221 @@ +/* + * Platform CAN bus driver for Bosch C_CAN controller + * + * Copyright (C) 2012 Federico Vaga + * + * 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 { + unsigned int reg_align; /* Set the register alignment in the memory */ + unsigned int freq; /* Set the frequency if clk is not usable */ +}; + +/* + * 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, + void *reg) +{ + return readw(reg); +} + +static void c_can_pci_write_reg_aligned_to_16bit(struct c_can_priv *priv, + void *reg, u16 val) +{ + writew(val, reg); +} + +static u16 c_can_pci_read_reg_aligned_to_32bit(struct c_can_priv *priv, + void *reg) +{ + return readw(reg + (long)reg - (long)priv->regs); +} + +static void c_can_pci_write_reg_aligned_to_32bit(struct c_can_priv *priv, + void *reg, u16 val) +{ + writew(val, reg + (long)reg - (long)priv->regs); +} + +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->regs = 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; + } + + 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: + default: + priv->read_reg = c_can_pci_read_reg_aligned_to_16bit; + priv->write_reg = c_can_pci_write_reg_aligned_to_16bit; + break; + } + + 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_info(&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: + /* + * do not call pci_disable_device on sta2x11 because it + * break all other Bus masters on this EP + */ + if(pdev->vendor == PCI_VENDOR_ID_STMICRO && + pdev->device == PCI_DEVICE_ID_STMICRO_CAN) + goto out; + 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); + + pci_set_drvdata(pdev, NULL); + free_c_can_dev(dev); + if (!priv->priv) + clk_put(priv->priv); + pci_iounmap(pdev, priv->regs); + pci_disable_msi(pdev); + pci_clear_master(pdev); + pci_release_regions(pdev); + /* + * do not call pci_disable_device on sta2x11 because it + * break all other Bus masters on this EP + */ + if(pdev->vendor == PCI_VENDOR_ID_STMICRO && + pdev->device == PCI_DEVICE_ID_STMICRO_CAN) + return; + pci_disable_device(pdev); +} + +static struct c_can_pci_data c_can_sta2x11= { + .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, \ +} +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 sta2x11_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(sta2x11_pci_driver); + +MODULE_AUTHOR("Federico Vaga "); +MODULE_LICENSE("GPL V2"); +MODULE_DESCRIPTION("PCI CAN bus driver for Bosch C_CAN controller"); +MODULE_DEVICE_TABLE(pci, c_can_pci_tbl); -- 1.7.10.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/