| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // IOMapped CAN bus driver for Bosch M_CAN controller |
| 3 | // Copyright (C) 2014 Freescale Semiconductor, Inc. |
| 4 | // Dong Aisheng <b29396@freescale.com> |
| 5 | // |
| 6 | // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/ |
| 7 | |
| 8 | #include <linux/hrtimer.h> |
| 9 | #include <linux/phy/phy.h> |
| 10 | #include <linux/platform_device.h> |
| 11 | |
| 12 | #include "m_can.h" |
| 13 | |
| 14 | struct m_can_plat_priv { |
| 15 | struct m_can_classdev cdev; |
| 16 | |
| 17 | void __iomem *base; |
| 18 | void __iomem *mram_base; |
| 19 | }; |
| 20 | |
| 21 | static inline struct m_can_plat_priv *cdev_to_priv(struct m_can_classdev *cdev) |
| 22 | { |
| 23 | return container_of(cdev, struct m_can_plat_priv, cdev); |
| 24 | } |
| 25 | |
| 26 | static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg) |
| 27 | { |
| 28 | struct m_can_plat_priv *priv = cdev_to_priv(cdev); |
| 29 | |
| 30 | return readl(priv->base + reg); |
| 31 | } |
| 32 | |
| 33 | static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count) |
| 34 | { |
| 35 | struct m_can_plat_priv *priv = cdev_to_priv(cdev); |
| 36 | void __iomem *src = priv->mram_base + offset; |
| 37 | |
| 38 | while (val_count--) { |
| 39 | *(unsigned int *)val = ioread32(src); |
| 40 | val += 4; |
| 41 | src += 4; |
| 42 | } |
| 43 | |
| 44 | return 0; |
| 45 | } |
| 46 | |
| 47 | static int iomap_write_reg(struct m_can_classdev *cdev, int reg, int val) |
| 48 | { |
| 49 | struct m_can_plat_priv *priv = cdev_to_priv(cdev); |
| 50 | |
| 51 | writel(val, priv->base + reg); |
| 52 | |
| 53 | return 0; |
| 54 | } |
| 55 | |
| 56 | static int iomap_write_fifo(struct m_can_classdev *cdev, int offset, |
| 57 | const void *val, size_t val_count) |
| 58 | { |
| 59 | struct m_can_plat_priv *priv = cdev_to_priv(cdev); |
| 60 | void __iomem *dst = priv->mram_base + offset; |
| 61 | |
| 62 | while (val_count--) { |
| 63 | iowrite32(*(unsigned int *)val, dst); |
| 64 | val += 4; |
| 65 | dst += 4; |
| 66 | } |
| 67 | |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static const struct m_can_ops m_can_plat_ops = { |
| 72 | .read_reg = iomap_read_reg, |
| 73 | .write_reg = iomap_write_reg, |
| 74 | .write_fifo = iomap_write_fifo, |
| 75 | .read_fifo = iomap_read_fifo, |
| 76 | }; |
| 77 | |
| 78 | static int m_can_plat_probe(struct platform_device *pdev) |
| 79 | { |
| 80 | struct m_can_classdev *mcan_class; |
| 81 | struct m_can_plat_priv *priv; |
| 82 | struct resource *res; |
| 83 | void __iomem *addr; |
| 84 | void __iomem *mram_addr; |
| 85 | struct phy *transceiver; |
| 86 | int irq = 0, ret = 0; |
| 87 | |
| 88 | mcan_class = m_can_class_allocate_dev(&pdev->dev, |
| 89 | sizeof(struct m_can_plat_priv)); |
| 90 | if (!mcan_class) |
| 91 | return -ENOMEM; |
| 92 | |
| 93 | priv = cdev_to_priv(mcan_class); |
| 94 | |
| 95 | ret = m_can_class_get_clocks(mcan_class); |
| 96 | if (ret) |
| 97 | goto probe_fail; |
| 98 | |
| 99 | addr = devm_platform_ioremap_resource_byname(pdev, "m_can"); |
| 100 | if (IS_ERR(addr)) { |
| 101 | ret = PTR_ERR(addr); |
| 102 | goto probe_fail; |
| 103 | } |
| 104 | |
| 105 | if (device_property_present(mcan_class->dev, "interrupts") || |
| 106 | device_property_present(mcan_class->dev, "interrupt-names")) { |
| 107 | irq = platform_get_irq_byname(pdev, "int0"); |
| 108 | if (irq < 0) { |
| 109 | ret = irq; |
| 110 | goto probe_fail; |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | /* message ram could be shared */ |
| 115 | res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram"); |
| 116 | if (!res) { |
| 117 | ret = -ENODEV; |
| 118 | goto probe_fail; |
| 119 | } |
| 120 | |
| 121 | mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res)); |
| 122 | if (!mram_addr) { |
| 123 | ret = -ENOMEM; |
| 124 | goto probe_fail; |
| 125 | } |
| 126 | |
| 127 | transceiver = devm_phy_optional_get(&pdev->dev, NULL); |
| 128 | if (IS_ERR(transceiver)) { |
| 129 | ret = PTR_ERR(transceiver); |
| 130 | dev_err_probe(&pdev->dev, ret, "failed to get phy\n"); |
| 131 | goto probe_fail; |
| 132 | } |
| 133 | |
| 134 | if (transceiver) |
| 135 | mcan_class->can.bitrate_max = transceiver->attrs.max_link_rate; |
| 136 | |
| 137 | priv->base = addr; |
| 138 | priv->mram_base = mram_addr; |
| 139 | |
| 140 | mcan_class->net->irq = irq; |
| 141 | mcan_class->pm_clock_support = 1; |
| 142 | mcan_class->pm_wake_source = 0; |
| 143 | mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk); |
| 144 | mcan_class->dev = &pdev->dev; |
| 145 | mcan_class->transceiver = transceiver; |
| 146 | |
| 147 | mcan_class->ops = &m_can_plat_ops; |
| 148 | |
| 149 | mcan_class->is_peripheral = false; |
| 150 | |
| 151 | platform_set_drvdata(pdev, mcan_class); |
| 152 | |
| 153 | pm_runtime_enable(mcan_class->dev); |
| 154 | ret = m_can_class_register(mcan_class); |
| 155 | if (ret) |
| 156 | goto out_runtime_disable; |
| 157 | |
| 158 | return ret; |
| 159 | |
| 160 | out_runtime_disable: |
| 161 | pm_runtime_disable(mcan_class->dev); |
| 162 | probe_fail: |
| 163 | m_can_class_free_dev(mcan_class->net); |
| 164 | return ret; |
| 165 | } |
| 166 | |
| 167 | static __maybe_unused int m_can_suspend(struct device *dev) |
| 168 | { |
| 169 | return m_can_class_suspend(dev); |
| 170 | } |
| 171 | |
| 172 | static __maybe_unused int m_can_resume(struct device *dev) |
| 173 | { |
| 174 | return m_can_class_resume(dev); |
| 175 | } |
| 176 | |
| 177 | static void m_can_plat_remove(struct platform_device *pdev) |
| 178 | { |
| 179 | struct m_can_plat_priv *priv = platform_get_drvdata(pdev); |
| 180 | struct m_can_classdev *mcan_class = &priv->cdev; |
| 181 | |
| 182 | m_can_class_unregister(mcan_class); |
| 183 | |
| 184 | m_can_class_free_dev(mcan_class->net); |
| 185 | } |
| 186 | |
| 187 | static int __maybe_unused m_can_runtime_suspend(struct device *dev) |
| 188 | { |
| 189 | struct m_can_plat_priv *priv = dev_get_drvdata(dev); |
| 190 | struct m_can_classdev *mcan_class = &priv->cdev; |
| 191 | |
| 192 | clk_disable_unprepare(mcan_class->cclk); |
| 193 | clk_disable_unprepare(mcan_class->hclk); |
| 194 | |
| 195 | return 0; |
| 196 | } |
| 197 | |
| 198 | static int __maybe_unused m_can_runtime_resume(struct device *dev) |
| 199 | { |
| 200 | struct m_can_plat_priv *priv = dev_get_drvdata(dev); |
| 201 | struct m_can_classdev *mcan_class = &priv->cdev; |
| 202 | int err; |
| 203 | |
| 204 | err = clk_prepare_enable(mcan_class->hclk); |
| 205 | if (err) |
| 206 | return err; |
| 207 | |
| 208 | err = clk_prepare_enable(mcan_class->cclk); |
| 209 | if (err) |
| 210 | clk_disable_unprepare(mcan_class->hclk); |
| 211 | |
| 212 | return err; |
| 213 | } |
| 214 | |
| 215 | static const struct dev_pm_ops m_can_pmops = { |
| 216 | SET_RUNTIME_PM_OPS(m_can_runtime_suspend, |
| 217 | m_can_runtime_resume, NULL) |
| 218 | SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume) |
| 219 | }; |
| 220 | |
| 221 | static const struct of_device_id m_can_of_table[] = { |
| 222 | { .compatible = "bosch,m_can", .data = NULL }, |
| 223 | { /* sentinel */ }, |
| 224 | }; |
| 225 | MODULE_DEVICE_TABLE(of, m_can_of_table); |
| 226 | |
| 227 | static struct platform_driver m_can_plat_driver = { |
| 228 | .driver = { |
| 229 | .name = KBUILD_MODNAME, |
| 230 | .of_match_table = m_can_of_table, |
| 231 | .pm = &m_can_pmops, |
| 232 | }, |
| 233 | .probe = m_can_plat_probe, |
| 234 | .remove = m_can_plat_remove, |
| 235 | }; |
| 236 | |
| 237 | module_platform_driver(m_can_plat_driver); |
| 238 | |
| 239 | MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>"); |
| 240 | MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); |
| 241 | MODULE_LICENSE("GPL v2"); |
| 242 | MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers"); |