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
 14struct m_can_plat_priv {
 15	struct m_can_classdev cdev;
 16
 17	void __iomem *base;
 18	void __iomem *mram_base;
 19};
 20
 21static 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
 26static 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
 33static 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
 47static 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
 56static 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
 71static 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
 78static 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
163out_runtime_disable:
164	pm_runtime_disable(mcan_class->dev);
165probe_fail:
166	m_can_class_free_dev(mcan_class->net);
167	return ret;
168}
169
170static __maybe_unused int m_can_suspend(struct device *dev)
171{
172	return m_can_class_suspend(dev);
173}
174
175static __maybe_unused int m_can_resume(struct device *dev)
176{
177	return m_can_class_resume(dev);
178}
179
180static 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
190static 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
201static 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
218static 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
224static const struct of_device_id m_can_of_table[] = {
225	{ .compatible = "bosch,m_can", .data = NULL },
226	{ /* sentinel */ },
227};
228MODULE_DEVICE_TABLE(of, m_can_of_table);
229
230static 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
240module_platform_driver(m_can_plat_driver);
241
242MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
243MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
244MODULE_LICENSE("GPL v2");
245MODULE_DESCRIPTION("M_CAN driver for IO Mapped Bosch controllers");