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 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 } else { 113 dev_dbg(mcan_class->dev, "Polling enabled, initialize hrtimer"); 114 hrtimer_init(&mcan_class->hrtimer, CLOCK_MONOTONIC, 115 HRTIMER_MODE_REL_PINNED); 116 } 117 118 /* message ram could be shared */ 119 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram"); 120 if (!res) { 121 ret = -ENODEV; 122 goto probe_fail; 123 } 124 125 mram_addr = devm_ioremap(&pdev->dev, res->start, resource_size(res)); 126 if (!mram_addr) { 127 ret = -ENOMEM; 128 goto probe_fail; 129 } 130 131 transceiver = devm_phy_optional_get(&pdev->dev, NULL); 132 if (IS_ERR(transceiver)) { 133 ret = PTR_ERR(transceiver); 134 dev_err_probe(&pdev->dev, ret, "failed to get phy\n"); 135 goto probe_fail; 136 } 137 138 if (transceiver) 139 mcan_class->can.bitrate_max = transceiver->attrs.max_link_rate; 140 141 priv->base = addr; 142 priv->mram_base = mram_addr; 143 144 mcan_class->net->irq = irq; 145 mcan_class->pm_clock_support = 1; 146 mcan_class->can.clock.freq = clk_get_rate(mcan_class->cclk); 147 mcan_class->dev = &pdev->dev; 148 mcan_class->transceiver = transceiver; 149 150 mcan_class->ops = &m_can_plat_ops; 151 152 mcan_class->is_peripheral = false; 153 154 platform_set_drvdata(pdev, mcan_class); 155 156 pm_runtime_enable(mcan_class->dev); 157 ret = m_can_class_register(mcan_class); 158 if (ret) 159 goto out_runtime_disable; 160 161 return ret; 162 163 out_runtime_disable: 164 pm_runtime_disable(mcan_class->dev); 165 probe_fail: 166 m_can_class_free_dev(mcan_class->net); 167 return ret; 168 } 169 170 static __maybe_unused int m_can_suspend(struct device *dev) 171 { 172 return m_can_class_suspend(dev); 173 } 174 175 static __maybe_unused int m_can_resume(struct device *dev) 176 { 177 return m_can_class_resume(dev); 178 } 179 180 static void m_can_plat_remove(struct platform_device *pdev) 181 { 182 struct m_can_plat_priv *priv = platform_get_drvdata(pdev); 183 struct m_can_classdev *mcan_class = &priv->cdev; 184 185 m_can_class_unregister(mcan_class); 186 187 m_can_class_free_dev(mcan_class->net); 188 } 189 190 static int __maybe_unused m_can_runtime_suspend(struct device *dev) 191 { 192 struct m_can_plat_priv *priv = dev_get_drvdata(dev); 193 struct m_can_classdev *mcan_class = &priv->cdev; 194 195 clk_disable_unprepare(mcan_class->cclk); 196 clk_disable_unprepare(mcan_class->hclk); 197 198 return 0; 199 } 200 201 static int __maybe_unused m_can_runtime_resume(struct device *dev) 202 { 203 struct m_can_plat_priv *priv = dev_get_drvdata(dev); 204 struct m_can_classdev *mcan_class = &priv->cdev; 205 int err; 206 207 err = clk_prepare_enable(mcan_class->hclk); 208 if (err) 209 return err; 210 211 err = clk_prepare_enable(mcan_class->cclk); 212 if (err) 213 clk_disable_unprepare(mcan_class->hclk); 214 215 return err; 216 } 217 218 static const struct dev_pm_ops m_can_pmops = { 219 SET_RUNTIME_PM_OPS(m_can_runtime_suspend, 220 m_can_runtime_resume, NULL) 221 SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume) 222 }; 223 224 static const struct of_device_id m_can_of_table[] = { 225 { .compatible = "bosch,m_can", .data = NULL }, 226 { /* sentinel */ }, 227 }; 228 MODULE_DEVICE_TABLE(of, m_can_of_table); 229 230 static struct platform_driver m_can_plat_driver = { 231 .driver = { 232 .name = KBUILD_MODNAME, 233 .of_match_table = m_can_of_table, 234 .pm = &m_can_pmops, 235 }, 236 .probe = m_can_plat_probe, 237 .remove_new = m_can_plat_remove, 238 }; 239 240 module_platform_driver(m_can_plat_driver); 241 242 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>"); 243 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); 244 MODULE_LICENSE("GPL v2"); 245 MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers"); 246