diff options
Diffstat (limited to 'drivers/net/can/c_can/c_can_platform.c')
| -rw-r--r-- | drivers/net/can/c_can/c_can_platform.c | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c new file mode 100644 index 00000000..d63b9190 --- /dev/null +++ b/drivers/net/can/c_can/c_can_platform.c @@ -0,0 +1,347 @@ +/* + * Platform CAN bus driver for Bosch C_CAN controller + * + * Copyright (C) 2010 ST Microelectronics + * Bhupesh Sharma <bhupesh.sharma@st.com> + * + * Borrowed heavily from the C_CAN driver originally written by: + * Copyright (C) 2007 + * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de> + * - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch> + * + * Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B. + * Bosch C_CAN user manual can be obtained from: + * http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/ + * users_manual_c_can.pdf + * + * 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/interrupt.h> +#include <linux/delay.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/if_ether.h> +#include <linux/list.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pinctrl/consumer.h> + +#include <linux/can/dev.h> + +#include "c_can.h" + +#define CAN_RAMINIT_START_MASK(i) (1 << (i)) + +/* + * 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_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv, + enum reg index) +{ + return readw(priv->base + priv->regs[index]); +} + +static void c_can_plat_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_plat_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_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv, + enum reg index, u16 val) +{ + writew(val, priv->base + 2 * priv->regs[index]); +} + +static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable) +{ + u32 val; + + val = readl(priv->raminit_ctrlreg); + if (enable) + val |= CAN_RAMINIT_START_MASK(priv->instance); + else + val &= ~CAN_RAMINIT_START_MASK(priv->instance); + writel(val, priv->raminit_ctrlreg); +} + +static struct platform_device_id c_can_id_table[] = { + [BOSCH_C_CAN_PLATFORM] = { + .name = KBUILD_MODNAME, + .driver_data = BOSCH_C_CAN, + }, + [BOSCH_C_CAN] = { + .name = "c_can", + .driver_data = BOSCH_C_CAN, + }, + [BOSCH_D_CAN] = { + .name = "d_can", + .driver_data = BOSCH_D_CAN, + }, { + } +}; +MODULE_DEVICE_TABLE(platform, c_can_id_table); + +static const struct of_device_id c_can_of_table[] = { + { .compatible = "bosch,c_can", .data = &c_can_id_table[BOSCH_C_CAN] }, + { .compatible = "bosch,d_can", .data = &c_can_id_table[BOSCH_D_CAN] }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, c_can_of_table); + +static int c_can_plat_probe(struct platform_device *pdev) +{ + int ret; + void __iomem *addr; + struct net_device *dev; + struct c_can_priv *priv; + const struct of_device_id *match; + const struct platform_device_id *id; + struct pinctrl *pinctrl; + struct resource *mem, *res; + int irq; + struct clk *clk; + + if (pdev->dev.of_node) { + match = of_match_device(c_can_of_table, &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "Failed to find matching dt id\n"); + ret = -EINVAL; + goto exit; + } + id = match->data; + } else { + id = platform_get_device_id(pdev); + } + + pinctrl = devm_pinctrl_get_select_default(&pdev->dev); + if (IS_ERR(pinctrl)) + dev_warn(&pdev->dev, + "failed to configure pins from driver\n"); + + /* 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 exit; + } + + /* get the platform data */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + irq = platform_get_irq(pdev, 0); + if (!mem || irq <= 0) { + ret = -ENODEV; + goto exit_free_clk; + } + + if (!request_mem_region(mem->start, resource_size(mem), + KBUILD_MODNAME)) { + dev_err(&pdev->dev, "resource unavailable\n"); + ret = -ENODEV; + goto exit_free_clk; + } + + addr = ioremap(mem->start, resource_size(mem)); + if (!addr) { + dev_err(&pdev->dev, "failed to map can port\n"); + ret = -ENOMEM; + goto exit_release_mem; + } + + /* allocate the c_can device */ + dev = alloc_c_can_dev(); + if (!dev) { + ret = -ENOMEM; + goto exit_iounmap; + } + + priv = netdev_priv(dev); + switch (id->driver_data) { + case BOSCH_C_CAN: + priv->regs = reg_map_c_can; + switch (mem->flags & IORESOURCE_MEM_TYPE_MASK) { + case IORESOURCE_MEM_32BIT: + priv->read_reg = c_can_plat_read_reg_aligned_to_32bit; + priv->write_reg = c_can_plat_write_reg_aligned_to_32bit; + break; + case IORESOURCE_MEM_16BIT: + default: + priv->read_reg = c_can_plat_read_reg_aligned_to_16bit; + priv->write_reg = c_can_plat_write_reg_aligned_to_16bit; + break; + } + break; + case BOSCH_D_CAN: + priv->regs = reg_map_d_can; + priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; + priv->read_reg = c_can_plat_read_reg_aligned_to_16bit; + priv->write_reg = c_can_plat_write_reg_aligned_to_16bit; + + if (pdev->dev.of_node) + priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can"); + else + priv->instance = pdev->id; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + priv->raminit_ctrlreg = devm_request_and_ioremap(&pdev->dev, res); + if (!priv->raminit_ctrlreg || priv->instance < 0) + dev_info(&pdev->dev, "control memory is not used for raminit\n"); + else + priv->raminit = c_can_hw_raminit; + break; + default: + ret = -EINVAL; + goto exit_free_device; + } + + dev->irq = irq; + priv->base = addr; + priv->device = &pdev->dev; + priv->can.clock.freq = clk_get_rate(clk); + priv->priv = clk; + priv->type = id->driver_data; + + platform_set_drvdata(pdev, dev); + SET_NETDEV_DEV(dev, &pdev->dev); + + ret = register_c_can_dev(dev); + if (ret) { + dev_err(&pdev->dev, "registering %s failed (err=%d)\n", + KBUILD_MODNAME, ret); + goto exit_free_device; + } + + dev_info(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n", + KBUILD_MODNAME, priv->base, dev->irq); + return 0; + +exit_free_device: + platform_set_drvdata(pdev, NULL); + free_c_can_dev(dev); +exit_iounmap: + iounmap(addr); +exit_release_mem: + release_mem_region(mem->start, resource_size(mem)); +exit_free_clk: + clk_put(clk); +exit: + dev_err(&pdev->dev, "probe failed\n"); + + return ret; +} + +static int c_can_plat_remove(struct platform_device *pdev) +{ + struct net_device *dev = platform_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(dev); + struct resource *mem; + + unregister_c_can_dev(dev); + platform_set_drvdata(pdev, NULL); + + free_c_can_dev(dev); + iounmap(priv->base); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mem->start, resource_size(mem)); + + clk_put(priv->priv); + + return 0; +} + +#ifdef CONFIG_PM +static int c_can_suspend(struct platform_device *pdev, pm_message_t state) +{ + int ret; + struct net_device *ndev = platform_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(ndev); + + if (priv->type != BOSCH_D_CAN) { + dev_warn(&pdev->dev, "Not supported\n"); + return 0; + } + + if (netif_running(ndev)) { + netif_stop_queue(ndev); + netif_device_detach(ndev); + } + + ret = c_can_power_down(ndev); + if (ret) { + netdev_err(ndev, "failed to enter power down mode\n"); + return ret; + } + + priv->can.state = CAN_STATE_SLEEPING; + + return 0; +} + +static int c_can_resume(struct platform_device *pdev) +{ + int ret; + struct net_device *ndev = platform_get_drvdata(pdev); + struct c_can_priv *priv = netdev_priv(ndev); + + if (priv->type != BOSCH_D_CAN) { + dev_warn(&pdev->dev, "Not supported\n"); + return 0; + } + + ret = c_can_power_up(ndev); + if (ret) { + netdev_err(ndev, "Still in power down mode\n"); + return ret; + } + + priv->can.state = CAN_STATE_ERROR_ACTIVE; + + if (netif_running(ndev)) { + netif_device_attach(ndev); + netif_start_queue(ndev); + } + + return 0; +} +#else +#define c_can_suspend NULL +#define c_can_resume NULL +#endif + +static struct platform_driver c_can_plat_driver = { + .driver = { + .name = KBUILD_MODNAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(c_can_of_table), + }, + .probe = c_can_plat_probe, + .remove = c_can_plat_remove, + .suspend = c_can_suspend, + .resume = c_can_resume, + .id_table = c_can_id_table, +}; + +module_platform_driver(c_can_plat_driver); + +MODULE_AUTHOR("Bhupesh Sharma <bhupesh.sharma@st.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Platform CAN bus driver for Bosch C_CAN controller"); |
