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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_optional(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 i2c->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
153 if (IS_ERR(i2c->reg_base))
154 return PTR_ERR(i2c->reg_base);
155
156
157 init_waitqueue_head(&i2c->wait);
158
159 i2c->io_base = res->start;
160 i2c->io_size = resource_size(res);
161 i2c->irq = irq;
162
163 i2c->adap.nr = pdev->id;
164 i2c->adap.owner = THIS_MODULE;
165 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
166 "PCA9564/PCA9665 at 0x%08lx",
167 (unsigned long) res->start);
168 i2c->adap.algo_data = &i2c->algo_data;
169 i2c->adap.dev.parent = &pdev->dev;
170 i2c->adap.dev.of_node = np;
171
172 i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
173 if (IS_ERR(i2c->gpio))
174 return PTR_ERR(i2c->gpio);
175
176 i2c->adap.timeout = HZ;
177 ret = device_property_read_u32(&pdev->dev, "clock-frequency",
178 &i2c->algo_data.i2c_clock);
179 if (ret)
180 i2c->algo_data.i2c_clock = 59000;
181
182 if (platform_data) {
183 i2c->adap.timeout = platform_data->timeout;
184 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
185 }
186
187 i2c->algo_data.data = i2c;
188 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
189 if (i2c->gpio)
190 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
191 else
192 i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
193
194 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
195 case IORESOURCE_MEM_32BIT:
196 i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
197 i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
198 break;
199 case IORESOURCE_MEM_16BIT:
200 i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
201 i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
202 break;
203 case IORESOURCE_MEM_8BIT:
204 default:
205 i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
206 i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
207 break;
208 }
209
210 if (irq) {
211 ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
212 IRQF_TRIGGER_FALLING, pdev->name, i2c);
213 if (ret)
214 return ret;
215 }
216
217 ret = i2c_pca_add_numbered_bus(&i2c->adap);
218 if (ret)
219 return ret;
220
221 platform_set_drvdata(pdev, i2c);
222
223 dev_info(&pdev->dev, "registered.\n");
224
225 return 0;
226}
227
228static int i2c_pca_pf_remove(struct platform_device *pdev)
229{
230 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
231
232 i2c_del_adapter(&i2c->adap);
233
234 return 0;
235}
236
237#ifdef CONFIG_OF
238static const struct of_device_id i2c_pca_of_match_table[] = {
239 { .compatible = "nxp,pca9564" },
240 { .compatible = "nxp,pca9665" },
241 {},
242};
243MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
244#endif
245
246static struct platform_driver i2c_pca_pf_driver = {
247 .probe = i2c_pca_pf_probe,
248 .remove = i2c_pca_pf_remove,
249 .driver = {
250 .name = "i2c-pca-platform",
251 .of_match_table = of_match_ptr(i2c_pca_of_match_table),
252 },
253};
254
255module_platform_driver(i2c_pca_pf_driver);
256
257MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
258MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
259MODULE_LICENSE("GPL");
1/*
2 * i2c_pca_platform.c
3 *
4 * Platform driver for the PCA9564 I2C controller.
5 *
6 * Copyright (C) 2008 Pengutronix
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11
12 */
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/delay.h>
18#include <linux/jiffies.h>
19#include <linux/errno.h>
20#include <linux/i2c.h>
21#include <linux/interrupt.h>
22#include <linux/platform_device.h>
23#include <linux/i2c-algo-pca.h>
24#include <linux/i2c-pca-platform.h>
25#include <linux/gpio.h>
26#include <linux/io.h>
27
28#include <asm/irq.h>
29
30struct i2c_pca_pf_data {
31 void __iomem *reg_base;
32 int irq; /* if 0, use polling */
33 int gpio;
34 wait_queue_head_t wait;
35 struct i2c_adapter adap;
36 struct i2c_algo_pca_data algo_data;
37 unsigned long io_base;
38 unsigned long io_size;
39};
40
41/* Read/Write functions for different register alignments */
42
43static int i2c_pca_pf_readbyte8(void *pd, int reg)
44{
45 struct i2c_pca_pf_data *i2c = pd;
46 return ioread8(i2c->reg_base + reg);
47}
48
49static int i2c_pca_pf_readbyte16(void *pd, int reg)
50{
51 struct i2c_pca_pf_data *i2c = pd;
52 return ioread8(i2c->reg_base + reg * 2);
53}
54
55static int i2c_pca_pf_readbyte32(void *pd, int reg)
56{
57 struct i2c_pca_pf_data *i2c = pd;
58 return ioread8(i2c->reg_base + reg * 4);
59}
60
61static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
62{
63 struct i2c_pca_pf_data *i2c = pd;
64 iowrite8(val, i2c->reg_base + reg);
65}
66
67static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
68{
69 struct i2c_pca_pf_data *i2c = pd;
70 iowrite8(val, i2c->reg_base + reg * 2);
71}
72
73static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
74{
75 struct i2c_pca_pf_data *i2c = pd;
76 iowrite8(val, i2c->reg_base + reg * 4);
77}
78
79
80static int i2c_pca_pf_waitforcompletion(void *pd)
81{
82 struct i2c_pca_pf_data *i2c = pd;
83 unsigned long timeout;
84 long ret;
85
86 if (i2c->irq) {
87 ret = wait_event_timeout(i2c->wait,
88 i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
89 & I2C_PCA_CON_SI, i2c->adap.timeout);
90 } else {
91 /* Do polling */
92 timeout = jiffies + i2c->adap.timeout;
93 do {
94 ret = time_before(jiffies, timeout);
95 if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
96 & I2C_PCA_CON_SI)
97 break;
98 udelay(100);
99 } while (ret);
100 }
101
102 return ret > 0;
103}
104
105static void i2c_pca_pf_dummyreset(void *pd)
106{
107 struct i2c_pca_pf_data *i2c = pd;
108 printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n",
109 i2c->adap.name);
110}
111
112static void i2c_pca_pf_resetchip(void *pd)
113{
114 struct i2c_pca_pf_data *i2c = pd;
115
116 gpio_set_value(i2c->gpio, 0);
117 ndelay(100);
118 gpio_set_value(i2c->gpio, 1);
119}
120
121static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
122{
123 struct i2c_pca_pf_data *i2c = dev_id;
124
125 if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
126 return IRQ_NONE;
127
128 wake_up(&i2c->wait);
129
130 return IRQ_HANDLED;
131}
132
133
134static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
135{
136 struct i2c_pca_pf_data *i2c;
137 struct resource *res;
138 struct i2c_pca9564_pf_platform_data *platform_data =
139 pdev->dev.platform_data;
140 int ret = 0;
141 int irq;
142
143 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
144 irq = platform_get_irq(pdev, 0);
145 /* If irq is 0, we do polling. */
146
147 if (res == NULL) {
148 ret = -ENODEV;
149 goto e_print;
150 }
151
152 if (!request_mem_region(res->start, resource_size(res), res->name)) {
153 ret = -ENOMEM;
154 goto e_print;
155 }
156
157 i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
158 if (!i2c) {
159 ret = -ENOMEM;
160 goto e_alloc;
161 }
162
163 init_waitqueue_head(&i2c->wait);
164
165 i2c->reg_base = ioremap(res->start, resource_size(res));
166 if (!i2c->reg_base) {
167 ret = -ENOMEM;
168 goto e_remap;
169 }
170 i2c->io_base = res->start;
171 i2c->io_size = resource_size(res);
172 i2c->irq = irq;
173
174 i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
175 i2c->adap.owner = THIS_MODULE;
176 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
177 "PCA9564/PCA9665 at 0x%08lx",
178 (unsigned long) res->start);
179 i2c->adap.algo_data = &i2c->algo_data;
180 i2c->adap.dev.parent = &pdev->dev;
181
182 if (platform_data) {
183 i2c->adap.timeout = platform_data->timeout;
184 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
185 i2c->gpio = platform_data->gpio;
186 } else {
187 i2c->adap.timeout = HZ;
188 i2c->algo_data.i2c_clock = 59000;
189 i2c->gpio = -1;
190 }
191
192 i2c->algo_data.data = i2c;
193 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
194 i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
195
196 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
197 case IORESOURCE_MEM_32BIT:
198 i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
199 i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
200 break;
201 case IORESOURCE_MEM_16BIT:
202 i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
203 i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
204 break;
205 case IORESOURCE_MEM_8BIT:
206 default:
207 i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
208 i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
209 break;
210 }
211
212 /* Use gpio_is_valid() when in mainline */
213 if (i2c->gpio > -1) {
214 ret = gpio_request(i2c->gpio, i2c->adap.name);
215 if (ret == 0) {
216 gpio_direction_output(i2c->gpio, 1);
217 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
218 } else {
219 printk(KERN_WARNING "%s: Registering gpio failed!\n",
220 i2c->adap.name);
221 i2c->gpio = ret;
222 }
223 }
224
225 if (irq) {
226 ret = request_irq(irq, i2c_pca_pf_handler,
227 IRQF_TRIGGER_FALLING, pdev->name, i2c);
228 if (ret)
229 goto e_reqirq;
230 }
231
232 if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
233 ret = -ENODEV;
234 goto e_adapt;
235 }
236
237 platform_set_drvdata(pdev, i2c);
238
239 printk(KERN_INFO "%s registered.\n", i2c->adap.name);
240
241 return 0;
242
243e_adapt:
244 if (irq)
245 free_irq(irq, i2c);
246e_reqirq:
247 if (i2c->gpio > -1)
248 gpio_free(i2c->gpio);
249
250 iounmap(i2c->reg_base);
251e_remap:
252 kfree(i2c);
253e_alloc:
254 release_mem_region(res->start, resource_size(res));
255e_print:
256 printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
257 return ret;
258}
259
260static int __devexit i2c_pca_pf_remove(struct platform_device *pdev)
261{
262 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
263 platform_set_drvdata(pdev, NULL);
264
265 i2c_del_adapter(&i2c->adap);
266
267 if (i2c->irq)
268 free_irq(i2c->irq, i2c);
269
270 if (i2c->gpio > -1)
271 gpio_free(i2c->gpio);
272
273 iounmap(i2c->reg_base);
274 release_mem_region(i2c->io_base, i2c->io_size);
275 kfree(i2c);
276
277 return 0;
278}
279
280static struct platform_driver i2c_pca_pf_driver = {
281 .probe = i2c_pca_pf_probe,
282 .remove = __devexit_p(i2c_pca_pf_remove),
283 .driver = {
284 .name = "i2c-pca-platform",
285 .owner = THIS_MODULE,
286 },
287};
288
289static int __init i2c_pca_pf_init(void)
290{
291 return platform_driver_register(&i2c_pca_pf_driver);
292}
293
294static void __exit i2c_pca_pf_exit(void)
295{
296 platform_driver_unregister(&i2c_pca_pf_driver);
297}
298
299MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
300MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
301MODULE_LICENSE("GPL");
302
303module_init(i2c_pca_pf_init);
304module_exit(i2c_pca_pf_exit);
305