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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Driver for CC770 and AN82527 CAN controllers on the platform bus
  4 *
  5 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com>
  6 */
  7
  8/*
  9 * If platform data are used you should have similar definitions
 10 * in your board-specific code:
 11 *
 12 *   static struct cc770_platform_data myboard_cc770_pdata = {
 13 *           .osc_freq = 16000000,
 14 *           .cir = 0x41,
 15 *           .cor = 0x20,
 16 *           .bcr = 0x40,
 17 *   };
 18 *
 19 * Please see include/linux/can/platform/cc770.h for description of
 20 * above fields.
 21 *
 22 * If the device tree is used, you need a CAN node definition in your
 23 * DTS file similar to:
 24 *
 25 *   can@3,100 {
 26 *           compatible = "bosch,cc770";
 27 *           reg = <3 0x100 0x80>;
 28 *           interrupts = <2 0>;
 29 *           interrupt-parent = <&mpic>;
 30 *           bosch,external-clock-frequency = <16000000>;
 31 *   };
 32 *
 33 * See "Documentation/devicetree/bindings/net/can/cc770.txt" for further
 34 * information.
 35 */
 36
 37#include <linux/kernel.h>
 38#include <linux/module.h>
 39#include <linux/interrupt.h>
 40#include <linux/netdevice.h>
 41#include <linux/delay.h>
 42#include <linux/platform_device.h>
 43#include <linux/of.h>
 44#include <linux/can.h>
 45#include <linux/can/dev.h>
 46#include <linux/can/platform/cc770.h>
 47
 48#include "cc770.h"
 49
 50#define DRV_NAME "cc770_platform"
 51
 52MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 53MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the platform bus");
 54MODULE_LICENSE("GPL v2");
 55MODULE_ALIAS("platform:" DRV_NAME);
 56
 57#define CC770_PLATFORM_CAN_CLOCK  16000000
 58
 59static u8 cc770_platform_read_reg(const struct cc770_priv *priv, int reg)
 60{
 61	return ioread8(priv->reg_base + reg);
 62}
 63
 64static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg,
 65				     u8 val)
 66{
 67	iowrite8(val, priv->reg_base + reg);
 68}
 69
 70static int cc770_get_of_node_data(struct platform_device *pdev,
 71				  struct cc770_priv *priv)
 72{
 73	struct device_node *np = pdev->dev.of_node;
 74	const u32 *prop;
 75	int prop_size;
 76	u32 clkext;
 77
 78	prop = of_get_property(np, "bosch,external-clock-frequency",
 79			       &prop_size);
 80	if (prop && (prop_size ==  sizeof(u32)))
 81		clkext = *prop;
 82	else
 83		clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
 84	priv->can.clock.freq = clkext;
 85
 86	/* The system clock may not exceed 10 MHz */
 87	if (priv->can.clock.freq > 10000000) {
 88		priv->cpu_interface |= CPUIF_DSC;
 89		priv->can.clock.freq /= 2;
 90	}
 91
 92	/* The memory clock may not exceed 8 MHz */
 93	if (priv->can.clock.freq > 8000000)
 94		priv->cpu_interface |= CPUIF_DMC;
 95
 96	if (of_property_read_bool(np, "bosch,divide-memory-clock"))
 97		priv->cpu_interface |= CPUIF_DMC;
 98	if (of_property_read_bool(np, "bosch,iso-low-speed-mux"))
 99		priv->cpu_interface |= CPUIF_MUX;
100
101	if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
102		priv->bus_config |= BUSCFG_CBY;
103	if (of_property_read_bool(np, "bosch,disconnect-rx0-input"))
104		priv->bus_config |= BUSCFG_DR0;
105	if (of_property_read_bool(np, "bosch,disconnect-rx1-input"))
106		priv->bus_config |= BUSCFG_DR1;
107	if (of_property_read_bool(np, "bosch,disconnect-tx1-output"))
108		priv->bus_config |= BUSCFG_DT1;
109	if (of_property_read_bool(np, "bosch,polarity-dominant"))
110		priv->bus_config |= BUSCFG_POL;
111
112	prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
113	if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
114		u32 cdv = clkext / *prop;
115		int slew;
116
117		if (cdv > 0 && cdv < 16) {
118			priv->cpu_interface |= CPUIF_CEN;
119			priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
120
121			prop = of_get_property(np, "bosch,slew-rate",
122					       &prop_size);
123			if (prop && (prop_size == sizeof(u32))) {
124				slew = *prop;
125			} else {
126				/* Determine default slew rate */
127				slew = (CLKOUT_SL_MASK >>
128					CLKOUT_SL_SHIFT) -
129					((cdv * clkext - 1) / 8000000);
130				if (slew < 0)
131					slew = 0;
132			}
133			priv->clkout |= (slew << CLKOUT_SL_SHIFT) &
134				CLKOUT_SL_MASK;
135		} else {
136			dev_dbg(&pdev->dev, "invalid clock-out-frequency\n");
137		}
138	}
139
140	return 0;
141}
142
143static int cc770_get_platform_data(struct platform_device *pdev,
144				   struct cc770_priv *priv)
145{
146
147	struct cc770_platform_data *pdata = dev_get_platdata(&pdev->dev);
148
149	priv->can.clock.freq = pdata->osc_freq;
150	if (priv->cpu_interface & CPUIF_DSC)
151		priv->can.clock.freq /= 2;
152	priv->clkout = pdata->cor;
153	priv->bus_config = pdata->bcr;
154	priv->cpu_interface = pdata->cir;
155
156	return 0;
157}
158
159static int cc770_platform_probe(struct platform_device *pdev)
160{
161	struct net_device *dev;
162	struct cc770_priv *priv;
163	struct resource *mem;
164	resource_size_t mem_size;
165	void __iomem *base;
166	int err, irq;
167
168	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
169	irq = platform_get_irq(pdev, 0);
170	if (!mem || irq <= 0)
171		return -ENODEV;
172
173	mem_size = resource_size(mem);
174	if (!request_mem_region(mem->start, mem_size, pdev->name))
175		return -EBUSY;
176
177	base = ioremap(mem->start, mem_size);
178	if (!base) {
179		err = -ENOMEM;
180		goto exit_release_mem;
181	}
182
183	dev = alloc_cc770dev(0);
184	if (!dev) {
185		err = -ENOMEM;
186		goto exit_unmap_mem;
187	}
188
189	dev->irq = irq;
190	priv = netdev_priv(dev);
191	priv->read_reg = cc770_platform_read_reg;
192	priv->write_reg = cc770_platform_write_reg;
193	priv->irq_flags = IRQF_SHARED;
194	priv->reg_base = base;
195
196	if (pdev->dev.of_node)
197		err = cc770_get_of_node_data(pdev, priv);
198	else if (dev_get_platdata(&pdev->dev))
199		err = cc770_get_platform_data(pdev, priv);
200	else
201		err = -ENODEV;
202	if (err)
203		goto exit_free_cc770;
204
205	dev_dbg(&pdev->dev,
206		 "reg_base=0x%p irq=%d clock=%d cpu_interface=0x%02x "
207		 "bus_config=0x%02x clkout=0x%02x\n",
208		 priv->reg_base, dev->irq, priv->can.clock.freq,
209		 priv->cpu_interface, priv->bus_config, priv->clkout);
210
211	platform_set_drvdata(pdev, dev);
212	SET_NETDEV_DEV(dev, &pdev->dev);
213
214	err = register_cc770dev(dev);
215	if (err) {
216		dev_err(&pdev->dev,
217			"couldn't register CC700 device (err=%d)\n", err);
218		goto exit_free_cc770;
219	}
220
221	return 0;
222
223exit_free_cc770:
224	free_cc770dev(dev);
225exit_unmap_mem:
226	iounmap(base);
227exit_release_mem:
228	release_mem_region(mem->start, mem_size);
229
230	return err;
231}
232
233static void cc770_platform_remove(struct platform_device *pdev)
234{
235	struct net_device *dev = platform_get_drvdata(pdev);
236	struct cc770_priv *priv = netdev_priv(dev);
237	struct resource *mem;
238
239	unregister_cc770dev(dev);
240	iounmap(priv->reg_base);
241	free_cc770dev(dev);
242
243	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
244	release_mem_region(mem->start, resource_size(mem));
 
 
245}
246
247static const struct of_device_id cc770_platform_table[] = {
248	{.compatible = "bosch,cc770"}, /* CC770 from Bosch */
249	{.compatible = "intc,82527"},  /* AN82527 from Intel CP */
250	{},
251};
252MODULE_DEVICE_TABLE(of, cc770_platform_table);
253
254static struct platform_driver cc770_platform_driver = {
255	.driver = {
256		.name = DRV_NAME,
257		.of_match_table = cc770_platform_table,
258	},
259	.probe = cc770_platform_probe,
260	.remove_new = cc770_platform_remove,
261};
262
263module_platform_driver(cc770_platform_driver);
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Driver for CC770 and AN82527 CAN controllers on the platform bus
  4 *
  5 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com>
  6 */
  7
  8/*
  9 * If platform data are used you should have similar definitions
 10 * in your board-specific code:
 11 *
 12 *   static struct cc770_platform_data myboard_cc770_pdata = {
 13 *           .osc_freq = 16000000,
 14 *           .cir = 0x41,
 15 *           .cor = 0x20,
 16 *           .bcr = 0x40,
 17 *   };
 18 *
 19 * Please see include/linux/can/platform/cc770.h for description of
 20 * above fields.
 21 *
 22 * If the device tree is used, you need a CAN node definition in your
 23 * DTS file similar to:
 24 *
 25 *   can@3,100 {
 26 *           compatible = "bosch,cc770";
 27 *           reg = <3 0x100 0x80>;
 28 *           interrupts = <2 0>;
 29 *           interrupt-parent = <&mpic>;
 30 *           bosch,external-clock-frequency = <16000000>;
 31 *   };
 32 *
 33 * See "Documentation/devicetree/bindings/net/can/cc770.txt" for further
 34 * information.
 35 */
 36
 37#include <linux/kernel.h>
 38#include <linux/module.h>
 39#include <linux/interrupt.h>
 40#include <linux/netdevice.h>
 41#include <linux/delay.h>
 42#include <linux/platform_device.h>
 43#include <linux/of.h>
 44#include <linux/can.h>
 45#include <linux/can/dev.h>
 46#include <linux/can/platform/cc770.h>
 47
 48#include "cc770.h"
 49
 50#define DRV_NAME "cc770_platform"
 51
 52MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 53MODULE_DESCRIPTION("Socket-CAN driver for CC770 on the platform bus");
 54MODULE_LICENSE("GPL v2");
 55MODULE_ALIAS("platform:" DRV_NAME);
 56
 57#define CC770_PLATFORM_CAN_CLOCK  16000000
 58
 59static u8 cc770_platform_read_reg(const struct cc770_priv *priv, int reg)
 60{
 61	return ioread8(priv->reg_base + reg);
 62}
 63
 64static void cc770_platform_write_reg(const struct cc770_priv *priv, int reg,
 65				     u8 val)
 66{
 67	iowrite8(val, priv->reg_base + reg);
 68}
 69
 70static int cc770_get_of_node_data(struct platform_device *pdev,
 71				  struct cc770_priv *priv)
 72{
 73	struct device_node *np = pdev->dev.of_node;
 74	const u32 *prop;
 75	int prop_size;
 76	u32 clkext;
 77
 78	prop = of_get_property(np, "bosch,external-clock-frequency",
 79			       &prop_size);
 80	if (prop && (prop_size ==  sizeof(u32)))
 81		clkext = *prop;
 82	else
 83		clkext = CC770_PLATFORM_CAN_CLOCK; /* default */
 84	priv->can.clock.freq = clkext;
 85
 86	/* The system clock may not exceed 10 MHz */
 87	if (priv->can.clock.freq > 10000000) {
 88		priv->cpu_interface |= CPUIF_DSC;
 89		priv->can.clock.freq /= 2;
 90	}
 91
 92	/* The memory clock may not exceed 8 MHz */
 93	if (priv->can.clock.freq > 8000000)
 94		priv->cpu_interface |= CPUIF_DMC;
 95
 96	if (of_get_property(np, "bosch,divide-memory-clock", NULL))
 97		priv->cpu_interface |= CPUIF_DMC;
 98	if (of_get_property(np, "bosch,iso-low-speed-mux", NULL))
 99		priv->cpu_interface |= CPUIF_MUX;
100
101	if (!of_get_property(np, "bosch,no-comperator-bypass", NULL))
102		priv->bus_config |= BUSCFG_CBY;
103	if (of_get_property(np, "bosch,disconnect-rx0-input", NULL))
104		priv->bus_config |= BUSCFG_DR0;
105	if (of_get_property(np, "bosch,disconnect-rx1-input", NULL))
106		priv->bus_config |= BUSCFG_DR1;
107	if (of_get_property(np, "bosch,disconnect-tx1-output", NULL))
108		priv->bus_config |= BUSCFG_DT1;
109	if (of_get_property(np, "bosch,polarity-dominant", NULL))
110		priv->bus_config |= BUSCFG_POL;
111
112	prop = of_get_property(np, "bosch,clock-out-frequency", &prop_size);
113	if (prop && (prop_size == sizeof(u32)) && *prop > 0) {
114		u32 cdv = clkext / *prop;
115		int slew;
116
117		if (cdv > 0 && cdv < 16) {
118			priv->cpu_interface |= CPUIF_CEN;
119			priv->clkout |= (cdv - 1) & CLKOUT_CD_MASK;
120
121			prop = of_get_property(np, "bosch,slew-rate",
122					       &prop_size);
123			if (prop && (prop_size == sizeof(u32))) {
124				slew = *prop;
125			} else {
126				/* Determine default slew rate */
127				slew = (CLKOUT_SL_MASK >>
128					CLKOUT_SL_SHIFT) -
129					((cdv * clkext - 1) / 8000000);
130				if (slew < 0)
131					slew = 0;
132			}
133			priv->clkout |= (slew << CLKOUT_SL_SHIFT) &
134				CLKOUT_SL_MASK;
135		} else {
136			dev_dbg(&pdev->dev, "invalid clock-out-frequency\n");
137		}
138	}
139
140	return 0;
141}
142
143static int cc770_get_platform_data(struct platform_device *pdev,
144				   struct cc770_priv *priv)
145{
146
147	struct cc770_platform_data *pdata = dev_get_platdata(&pdev->dev);
148
149	priv->can.clock.freq = pdata->osc_freq;
150	if (priv->cpu_interface & CPUIF_DSC)
151		priv->can.clock.freq /= 2;
152	priv->clkout = pdata->cor;
153	priv->bus_config = pdata->bcr;
154	priv->cpu_interface = pdata->cir;
155
156	return 0;
157}
158
159static int cc770_platform_probe(struct platform_device *pdev)
160{
161	struct net_device *dev;
162	struct cc770_priv *priv;
163	struct resource *mem;
164	resource_size_t mem_size;
165	void __iomem *base;
166	int err, irq;
167
168	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
169	irq = platform_get_irq(pdev, 0);
170	if (!mem || irq <= 0)
171		return -ENODEV;
172
173	mem_size = resource_size(mem);
174	if (!request_mem_region(mem->start, mem_size, pdev->name))
175		return -EBUSY;
176
177	base = ioremap(mem->start, mem_size);
178	if (!base) {
179		err = -ENOMEM;
180		goto exit_release_mem;
181	}
182
183	dev = alloc_cc770dev(0);
184	if (!dev) {
185		err = -ENOMEM;
186		goto exit_unmap_mem;
187	}
188
189	dev->irq = irq;
190	priv = netdev_priv(dev);
191	priv->read_reg = cc770_platform_read_reg;
192	priv->write_reg = cc770_platform_write_reg;
193	priv->irq_flags = IRQF_SHARED;
194	priv->reg_base = base;
195
196	if (pdev->dev.of_node)
197		err = cc770_get_of_node_data(pdev, priv);
198	else if (dev_get_platdata(&pdev->dev))
199		err = cc770_get_platform_data(pdev, priv);
200	else
201		err = -ENODEV;
202	if (err)
203		goto exit_free_cc770;
204
205	dev_dbg(&pdev->dev,
206		 "reg_base=0x%p irq=%d clock=%d cpu_interface=0x%02x "
207		 "bus_config=0x%02x clkout=0x%02x\n",
208		 priv->reg_base, dev->irq, priv->can.clock.freq,
209		 priv->cpu_interface, priv->bus_config, priv->clkout);
210
211	platform_set_drvdata(pdev, dev);
212	SET_NETDEV_DEV(dev, &pdev->dev);
213
214	err = register_cc770dev(dev);
215	if (err) {
216		dev_err(&pdev->dev,
217			"couldn't register CC700 device (err=%d)\n", err);
218		goto exit_free_cc770;
219	}
220
221	return 0;
222
223exit_free_cc770:
224	free_cc770dev(dev);
225exit_unmap_mem:
226	iounmap(base);
227exit_release_mem:
228	release_mem_region(mem->start, mem_size);
229
230	return err;
231}
232
233static int cc770_platform_remove(struct platform_device *pdev)
234{
235	struct net_device *dev = platform_get_drvdata(pdev);
236	struct cc770_priv *priv = netdev_priv(dev);
237	struct resource *mem;
238
239	unregister_cc770dev(dev);
240	iounmap(priv->reg_base);
241	free_cc770dev(dev);
242
243	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
244	release_mem_region(mem->start, resource_size(mem));
245
246	return 0;
247}
248
249static const struct of_device_id cc770_platform_table[] = {
250	{.compatible = "bosch,cc770"}, /* CC770 from Bosch */
251	{.compatible = "intc,82527"},  /* AN82527 from Intel CP */
252	{},
253};
254MODULE_DEVICE_TABLE(of, cc770_platform_table);
255
256static struct platform_driver cc770_platform_driver = {
257	.driver = {
258		.name = DRV_NAME,
259		.of_match_table = cc770_platform_table,
260	},
261	.probe = cc770_platform_probe,
262	.remove = cc770_platform_remove,
263};
264
265module_platform_driver(cc770_platform_driver);