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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  i2c_pca_platform.c
  4 *
  5 *  Platform driver for the PCA9564 I2C controller.
  6 *
  7 *  Copyright (C) 2008 Pengutronix
  8 *
  9
 10 */
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14#include <linux/delay.h>
 15#include <linux/jiffies.h>
 16#include <linux/errno.h>
 17#include <linux/i2c.h>
 18#include <linux/interrupt.h>
 19#include <linux/platform_device.h>
 20#include <linux/i2c-algo-pca.h>
 21#include <linux/platform_data/i2c-pca-platform.h>
 22#include <linux/gpio/consumer.h>
 23#include <linux/io.h>
 24#include <linux/of.h>
 
 25
 26#include <asm/irq.h>
 27
 28struct i2c_pca_pf_data {
 29	void __iomem			*reg_base;
 30	int				irq;	/* if 0, use polling */
 31	struct gpio_desc		*gpio;
 32	wait_queue_head_t		wait;
 33	struct i2c_adapter		adap;
 34	struct i2c_algo_pca_data	algo_data;
 
 
 35};
 36
 37/* Read/Write functions for different register alignments */
 38
 39static int i2c_pca_pf_readbyte8(void *pd, int reg)
 40{
 41	struct i2c_pca_pf_data *i2c = pd;
 42	return ioread8(i2c->reg_base + reg);
 43}
 44
 45static int i2c_pca_pf_readbyte16(void *pd, int reg)
 46{
 47	struct i2c_pca_pf_data *i2c = pd;
 48	return ioread8(i2c->reg_base + reg * 2);
 49}
 50
 51static int i2c_pca_pf_readbyte32(void *pd, int reg)
 52{
 53	struct i2c_pca_pf_data *i2c = pd;
 54	return ioread8(i2c->reg_base + reg * 4);
 55}
 56
 57static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
 58{
 59	struct i2c_pca_pf_data *i2c = pd;
 60	iowrite8(val, i2c->reg_base + reg);
 61}
 62
 63static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
 64{
 65	struct i2c_pca_pf_data *i2c = pd;
 66	iowrite8(val, i2c->reg_base + reg * 2);
 67}
 68
 69static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
 70{
 71	struct i2c_pca_pf_data *i2c = pd;
 72	iowrite8(val, i2c->reg_base + reg * 4);
 73}
 74
 75
 76static int i2c_pca_pf_waitforcompletion(void *pd)
 77{
 78	struct i2c_pca_pf_data *i2c = pd;
 79	unsigned long timeout;
 80	long ret;
 81
 82	if (i2c->irq) {
 83		ret = wait_event_timeout(i2c->wait,
 84			i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
 85			& I2C_PCA_CON_SI, i2c->adap.timeout);
 86	} else {
 87		/* Do polling */
 88		timeout = jiffies + i2c->adap.timeout;
 89		do {
 90			ret = time_before(jiffies, timeout);
 91			if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
 92					& I2C_PCA_CON_SI)
 93				break;
 94			udelay(100);
 95		} while (ret);
 96	}
 97
 98	return ret > 0;
 99}
100
101static void i2c_pca_pf_dummyreset(void *pd)
102{
103	struct i2c_pca_pf_data *i2c = pd;
104
105	dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
106}
107
108static void i2c_pca_pf_resetchip(void *pd)
109{
110	struct i2c_pca_pf_data *i2c = pd;
111
112	gpiod_set_value(i2c->gpio, 1);
113	ndelay(100);
114	gpiod_set_value(i2c->gpio, 0);
115}
116
117static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
118{
119	struct i2c_pca_pf_data *i2c = dev_id;
120
121	if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
122		return IRQ_NONE;
123
124	wake_up(&i2c->wait);
125
126	return IRQ_HANDLED;
127}
128
129
130static int i2c_pca_pf_probe(struct platform_device *pdev)
131{
132	struct i2c_pca_pf_data *i2c;
133	struct resource *res;
134	struct i2c_pca9564_pf_platform_data *platform_data =
135				dev_get_platdata(&pdev->dev);
136	struct device_node *np = pdev->dev.of_node;
137	int ret = 0;
138	int irq;
139
140	irq = platform_get_irq_optional(pdev, 0);
141	/* If irq is 0, we do polling. */
142	if (irq < 0)
143		irq = 0;
144
145	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
146	if (!i2c)
147		return -ENOMEM;
148
149	i2c->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 
150	if (IS_ERR(i2c->reg_base))
151		return PTR_ERR(i2c->reg_base);
152
153
154	init_waitqueue_head(&i2c->wait);
155
 
 
156	i2c->irq = irq;
157
158	i2c->adap.nr = pdev->id;
159	i2c->adap.owner = THIS_MODULE;
160	snprintf(i2c->adap.name, sizeof(i2c->adap.name),
161		 "PCA9564/PCA9665 at 0x%08lx",
162		 (unsigned long) res->start);
163	i2c->adap.algo_data = &i2c->algo_data;
164	i2c->adap.dev.parent = &pdev->dev;
165	i2c->adap.dev.of_node = np;
166
167	i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
168	if (IS_ERR(i2c->gpio))
169		return PTR_ERR(i2c->gpio);
170
171	i2c->adap.timeout = HZ;
172	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
173				       &i2c->algo_data.i2c_clock);
174	if (ret)
175		i2c->algo_data.i2c_clock = 59000;
176
177	if (platform_data) {
178		i2c->adap.timeout = platform_data->timeout;
179		i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
180	}
181
182	i2c->algo_data.data = i2c;
183	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
184	if (i2c->gpio)
185		i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
186	else
187		i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
188
189	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
190	case IORESOURCE_MEM_32BIT:
191		i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
192		i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
193		break;
194	case IORESOURCE_MEM_16BIT:
195		i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
196		i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
197		break;
198	case IORESOURCE_MEM_8BIT:
199	default:
200		i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
201		i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
202		break;
203	}
204
205	if (irq) {
206		ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
207			IRQF_TRIGGER_FALLING, pdev->name, i2c);
208		if (ret)
209			return ret;
210	}
211
212	ret = i2c_pca_add_numbered_bus(&i2c->adap);
213	if (ret)
214		return ret;
215
216	platform_set_drvdata(pdev, i2c);
217
218	dev_info(&pdev->dev, "registered.\n");
219
220	return 0;
221}
222
223static void i2c_pca_pf_remove(struct platform_device *pdev)
224{
225	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
226
227	i2c_del_adapter(&i2c->adap);
 
 
228}
229
230#ifdef CONFIG_OF
231static const struct of_device_id i2c_pca_of_match_table[] = {
232	{ .compatible = "nxp,pca9564" },
233	{ .compatible = "nxp,pca9665" },
234	{},
235};
236MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
237#endif
238
239static struct platform_driver i2c_pca_pf_driver = {
240	.probe = i2c_pca_pf_probe,
241	.remove_new = i2c_pca_pf_remove,
242	.driver = {
243		.name = "i2c-pca-platform",
244		.of_match_table = of_match_ptr(i2c_pca_of_match_table),
245	},
246};
247
248module_platform_driver(i2c_pca_pf_driver);
249
250MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
251MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
252MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  i2c_pca_platform.c
  4 *
  5 *  Platform driver for the PCA9564 I2C controller.
  6 *
  7 *  Copyright (C) 2008 Pengutronix
  8 *
  9
 10 */
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14#include <linux/delay.h>
 15#include <linux/jiffies.h>
 16#include <linux/errno.h>
 17#include <linux/i2c.h>
 18#include <linux/interrupt.h>
 19#include <linux/platform_device.h>
 20#include <linux/i2c-algo-pca.h>
 21#include <linux/platform_data/i2c-pca-platform.h>
 22#include <linux/gpio/consumer.h>
 23#include <linux/io.h>
 24#include <linux/of.h>
 25#include <linux/of_device.h>
 26
 27#include <asm/irq.h>
 28
 29struct i2c_pca_pf_data {
 30	void __iomem			*reg_base;
 31	int				irq;	/* if 0, use polling */
 32	struct gpio_desc		*gpio;
 33	wait_queue_head_t		wait;
 34	struct i2c_adapter		adap;
 35	struct i2c_algo_pca_data	algo_data;
 36	unsigned long			io_base;
 37	unsigned long			io_size;
 38};
 39
 40/* Read/Write functions for different register alignments */
 41
 42static int i2c_pca_pf_readbyte8(void *pd, int reg)
 43{
 44	struct i2c_pca_pf_data *i2c = pd;
 45	return ioread8(i2c->reg_base + reg);
 46}
 47
 48static int i2c_pca_pf_readbyte16(void *pd, int reg)
 49{
 50	struct i2c_pca_pf_data *i2c = pd;
 51	return ioread8(i2c->reg_base + reg * 2);
 52}
 53
 54static int i2c_pca_pf_readbyte32(void *pd, int reg)
 55{
 56	struct i2c_pca_pf_data *i2c = pd;
 57	return ioread8(i2c->reg_base + reg * 4);
 58}
 59
 60static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
 61{
 62	struct i2c_pca_pf_data *i2c = pd;
 63	iowrite8(val, i2c->reg_base + reg);
 64}
 65
 66static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
 67{
 68	struct i2c_pca_pf_data *i2c = pd;
 69	iowrite8(val, i2c->reg_base + reg * 2);
 70}
 71
 72static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
 73{
 74	struct i2c_pca_pf_data *i2c = pd;
 75	iowrite8(val, i2c->reg_base + reg * 4);
 76}
 77
 78
 79static int i2c_pca_pf_waitforcompletion(void *pd)
 80{
 81	struct i2c_pca_pf_data *i2c = pd;
 82	unsigned long timeout;
 83	long ret;
 84
 85	if (i2c->irq) {
 86		ret = wait_event_timeout(i2c->wait,
 87			i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
 88			& I2C_PCA_CON_SI, i2c->adap.timeout);
 89	} else {
 90		/* Do polling */
 91		timeout = jiffies + i2c->adap.timeout;
 92		do {
 93			ret = time_before(jiffies, timeout);
 94			if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
 95					& I2C_PCA_CON_SI)
 96				break;
 97			udelay(100);
 98		} while (ret);
 99	}
100
101	return ret > 0;
102}
103
104static void i2c_pca_pf_dummyreset(void *pd)
105{
106	struct i2c_pca_pf_data *i2c = pd;
107
108	dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
109}
110
111static void i2c_pca_pf_resetchip(void *pd)
112{
113	struct i2c_pca_pf_data *i2c = pd;
114
115	gpiod_set_value(i2c->gpio, 1);
116	ndelay(100);
117	gpiod_set_value(i2c->gpio, 0);
118}
119
120static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
121{
122	struct i2c_pca_pf_data *i2c = dev_id;
123
124	if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
125		return IRQ_NONE;
126
127	wake_up(&i2c->wait);
128
129	return IRQ_HANDLED;
130}
131
132
133static int i2c_pca_pf_probe(struct platform_device *pdev)
134{
135	struct i2c_pca_pf_data *i2c;
136	struct resource *res;
137	struct i2c_pca9564_pf_platform_data *platform_data =
138				dev_get_platdata(&pdev->dev);
139	struct device_node *np = pdev->dev.of_node;
140	int ret = 0;
141	int irq;
142
143	irq = platform_get_irq(pdev, 0);
144	/* If irq is 0, we do polling. */
145	if (irq < 0)
146		irq = 0;
147
148	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
149	if (!i2c)
150		return -ENOMEM;
151
152	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
153	i2c->reg_base = devm_ioremap_resource(&pdev->dev, res);
154	if (IS_ERR(i2c->reg_base))
155		return PTR_ERR(i2c->reg_base);
156
157
158	init_waitqueue_head(&i2c->wait);
159
160	i2c->io_base = res->start;
161	i2c->io_size = resource_size(res);
162	i2c->irq = irq;
163
164	i2c->adap.nr = pdev->id;
165	i2c->adap.owner = THIS_MODULE;
166	snprintf(i2c->adap.name, sizeof(i2c->adap.name),
167		 "PCA9564/PCA9665 at 0x%08lx",
168		 (unsigned long) res->start);
169	i2c->adap.algo_data = &i2c->algo_data;
170	i2c->adap.dev.parent = &pdev->dev;
171	i2c->adap.dev.of_node = np;
172
173	i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
174	if (IS_ERR(i2c->gpio))
175		return PTR_ERR(i2c->gpio);
176
177	i2c->adap.timeout = HZ;
178	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
179				       &i2c->algo_data.i2c_clock);
180	if (ret)
181		i2c->algo_data.i2c_clock = 59000;
182
183	if (platform_data) {
184		i2c->adap.timeout = platform_data->timeout;
185		i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
186	}
187
188	i2c->algo_data.data = i2c;
189	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
190	if (i2c->gpio)
191		i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
192	else
193		i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
194
195	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
196	case IORESOURCE_MEM_32BIT:
197		i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
198		i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
199		break;
200	case IORESOURCE_MEM_16BIT:
201		i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
202		i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
203		break;
204	case IORESOURCE_MEM_8BIT:
205	default:
206		i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
207		i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
208		break;
209	}
210
211	if (irq) {
212		ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
213			IRQF_TRIGGER_FALLING, pdev->name, i2c);
214		if (ret)
215			return ret;
216	}
217
218	ret = i2c_pca_add_numbered_bus(&i2c->adap);
219	if (ret)
220		return ret;
221
222	platform_set_drvdata(pdev, i2c);
223
224	dev_info(&pdev->dev, "registered.\n");
225
226	return 0;
227}
228
229static int i2c_pca_pf_remove(struct platform_device *pdev)
230{
231	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
232
233	i2c_del_adapter(&i2c->adap);
234
235	return 0;
236}
237
238#ifdef CONFIG_OF
239static const struct of_device_id i2c_pca_of_match_table[] = {
240	{ .compatible = "nxp,pca9564" },
241	{ .compatible = "nxp,pca9665" },
242	{},
243};
244MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
245#endif
246
247static struct platform_driver i2c_pca_pf_driver = {
248	.probe = i2c_pca_pf_probe,
249	.remove = i2c_pca_pf_remove,
250	.driver = {
251		.name = "i2c-pca-platform",
252		.of_match_table = of_match_ptr(i2c_pca_of_match_table),
253	},
254};
255
256module_platform_driver(i2c_pca_pf_driver);
257
258MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
259MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
260MODULE_LICENSE("GPL");